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-rw-r--r--Documentation/arm64/acpi_object_usage.txt593
-rw-r--r--Documentation/arm64/arm-acpi.txt505
-rw-r--r--Documentation/kernel-parameters.txt3
-rw-r--r--arch/arm64/Kconfig4
-rw-r--r--arch/arm64/include/asm/acenv.h18
-rw-r--r--arch/arm64/include/asm/acpi.h96
-rw-r--r--arch/arm64/include/asm/cpu_ops.h1
-rw-r--r--arch/arm64/include/asm/fixmap.h3
-rw-r--r--arch/arm64/include/asm/irq.h13
-rw-r--r--arch/arm64/include/asm/pci.h6
-rw-r--r--arch/arm64/include/asm/psci.h3
-rw-r--r--arch/arm64/include/asm/smp.h5
-rw-r--r--arch/arm64/kernel/Makefile1
-rw-r--r--arch/arm64/kernel/acpi.c345
-rw-r--r--arch/arm64/kernel/cpu_ops.c2
-rw-r--r--arch/arm64/kernel/pci.c25
-rw-r--r--arch/arm64/kernel/psci.c112
-rw-r--r--arch/arm64/kernel/setup.c21
-rw-r--r--arch/arm64/kernel/smp.c2
-rw-r--r--arch/arm64/kernel/time.c7
-rw-r--r--arch/ia64/Kconfig1
-rw-r--r--arch/ia64/kernel/acpi.c2
-rw-r--r--arch/x86/Kconfig1
-rw-r--r--arch/x86/kernel/acpi/boot.c2
-rw-r--r--drivers/acpi/Kconfig10
-rw-r--r--drivers/acpi/Makefile3
-rw-r--r--drivers/acpi/acpi_processor.c7
-rw-r--r--drivers/acpi/bus.c3
-rw-r--r--drivers/acpi/gsi.c105
-rw-r--r--drivers/acpi/internal.h4
-rw-r--r--drivers/acpi/osl.c6
-rw-r--r--drivers/acpi/processor_core.c60
-rw-r--r--drivers/acpi/tables.c52
-rw-r--r--drivers/clocksource/arm_arch_timer.c132
-rw-r--r--drivers/irqchip/irq-gic.c104
-rw-r--r--drivers/irqchip/irqchip.c3
-rw-r--r--drivers/xen/Kconfig4
-rw-r--r--drivers/xen/Makefile2
-rw-r--r--include/acpi/acpi_io.h4
-rw-r--r--include/acpi/processor.h6
-rw-r--r--include/linux/acpi.h8
-rw-r--r--include/linux/acpi_irq.h10
-rw-r--r--include/linux/clocksource.h6
-rw-r--r--include/linux/irqchip/arm-gic-acpi.h31
44 files changed, 2216 insertions, 115 deletions
diff --git a/Documentation/arm64/acpi_object_usage.txt b/Documentation/arm64/acpi_object_usage.txt
new file mode 100644
index 000000000000..a6e1a1805e51
--- /dev/null
+++ b/Documentation/arm64/acpi_object_usage.txt
@@ -0,0 +1,593 @@
+ACPI Tables
+-----------
+The expectations of individual ACPI tables are discussed in the list that
+follows.
+
+If a section number is used, it refers to a section number in the ACPI
+specification where the object is defined.  If "Signature Reserved" is used,
+the table signature (the first four bytes of the table) is the only portion
+of the table recognized by the specification, and the actual table is defined
+outside of the UEFI Forum (see Section 5.2.6 of the specification).
+
+For ACPI on arm64, tables also fall into the following categories:
+
+       -- Required: DSDT, FADT, GTDT, MADT, MCFG, RSDP, SPCR, XSDT
+
+       -- Recommended: BERT, EINJ, ERST, HEST, SSDT
+
+       -- Optional: BGRT, CPEP, CSRT, DRTM, ECDT, FACS, FPDT, MCHI, MPST,
+          MSCT, RASF, SBST, SLIT, SPMI, SRAT, TCPA, TPM2, UEFI
+
+       -- Not supported: BOOT, DBG2, DBGP, DMAR, ETDT, HPET, IBFT, IVRS,
+          LPIT, MSDM, RSDT, SLIC, WAET, WDAT, WDRT, WPBT
+
+
+Table  Usage for ARMv8 Linux
+-----  ----------------------------------------------------------------
+BERT   Section 18.3 (signature == "BERT")
+       == Boot Error Record Table ==
+       Must be supplied if RAS support is provided by the platform.  It
+       is recommended this table be supplied.
+
+BOOT   Signature Reserved (signature == "BOOT")
+       == simple BOOT flag table ==
+       Microsoft only table, will not be supported.
+
+BGRT   Section 5.2.22 (signature == "BGRT")
+       == Boot Graphics Resource Table ==
+       Optional, not currently supported, with no real use-case for an
+       ARM server.
+
+CPEP   Section 5.2.18 (signature == "CPEP")
+       == Corrected Platform Error Polling table ==
+       Optional, not currently supported, and not recommended until such
+       time as ARM-compatible hardware is available, and the specification
+       suitably modified.
+
+CSRT   Signature Reserved (signature == "CSRT")
+       == Core System Resources Table ==
+       Optional, not currently supported.
+
+DBG2   Signature Reserved (signature == "DBG2")
+       == DeBuG port table 2 ==
+       Microsoft only table, will not be supported.
+
+DBGP   Signature Reserved (signature == "DBGP")
+       == DeBuG Port table ==
+       Microsoft only table, will not be supported.
+
+DSDT   Section 5.2.11.1 (signature == "DSDT")
+       == Differentiated System Description Table ==
+       A DSDT is required; see also SSDT.
+
+       ACPI tables contain only one DSDT but can contain one or more SSDTs,
+       which are optional.  Each SSDT can only add to the ACPI namespace,
+       but cannot modify or replace anything in the DSDT.
+
+DMAR   Signature Reserved (signature == "DMAR")
+       == DMA Remapping table ==
+       x86 only table, will not be supported.
+
+DRTM   Signature Reserved (signature == "DRTM")
+       == Dynamic Root of Trust for Measurement table ==
+       Optional, not currently supported.
+
+ECDT   Section 5.2.16 (signature == "ECDT")
+       == Embedded Controller Description Table ==
+       Optional, not currently supported, but could be used on ARM if and
+       only if one uses the GPE_BIT field to represent an IRQ number, since
+       there are no GPE blocks defined in hardware reduced mode.  This would
+       need to be modified in the ACPI specification.
+
+EINJ   Section 18.6 (signature == "EINJ")
+       == Error Injection table ==
+       This table is very useful for testing platform response to error
+       conditions; it allows one to inject an error into the system as
+       if it had actually occurred.  However, this table should not be
+       shipped with a production system; it should be dynamically loaded
+       and executed with the ACPICA tools only during testing.
+
+ERST   Section 18.5 (signature == "ERST")
+       == Error Record Serialization Table ==
+       On a platform supports RAS, this table must be supplied if it is not
+       UEFI-based; if it is UEFI-based, this table may be supplied. When this
+       table is not present, UEFI run time service will be utilized to save
+       and retrieve hardware error information to and from a persistent store.
+
+ETDT   Signature Reserved (signature == "ETDT")
+       == Event Timer Description Table ==
+       Obsolete table, will not be supported.
+
+FACS   Section 5.2.10 (signature == "FACS")
+       == Firmware ACPI Control Structure ==
+       It is unlikely that this table will be terribly useful.  If it is
+       provided, the Global Lock will NOT be used since it is not part of
+       the hardware reduced profile, and only 64-bit address fields will
+       be considered valid.
+
+FADT   Section 5.2.9 (signature == "FACP")
+       == Fixed ACPI Description Table ==
+       Required for arm64.
+
+       The HW_REDUCED_ACPI flag must be set.  All of the fields that are
+       to be ignored when HW_REDUCED_ACPI is set are expected to be set to
+       zero.
+
+       If an FACS table is provided, the X_FIRMWARE_CTRL field is to be
+       used, not FIRMWARE_CTRL.
+
+       If PSCI is used (as is recommended), make sure that ARM_BOOT_ARCH is
+       filled in properly -- that the PSCI_COMPLIANT flag is set and that
+       PSCI_USE_HVC is set or unset as needed (see table 5-37).
+
+       For the DSDT that is also required, the X_DSDT field is to be used,
+       not the DSDT field.
+
+FPDT   Section 5.2.23 (signature == "FPDT")
+       == Firmware Performance Data Table ==
+       Optional, not currently supported.
+
+GTDT   Section 5.2.24 (signature == "GTDT")
+       == Generic Timer Description Table ==
+       Required for arm64.
+
+HEST   Section 18.3.2 (signature == "HEST")
+       == Hardware Error Source Table ==
+       Until further error source types are defined, use only types 6 (AER
+       Root Port), 7 (AER Endpoint), 8 (AER Bridge), or 9 (Generic Hardware
+       Error Source).  Firmware first error handling is possible if and only
+       if Trusted Firmware is being used on arm64.
+
+       Must be supplied if RAS support is provided by the platform.  It
+       is recommended this table be supplied.
+
+HPET   Signature Reserved (signature == "HPET")
+       == High Precision Event timer Table ==
+       x86 only table, will not be supported.
+
+IBFT   Signature Reserved (signature == "IBFT")
+       == iSCSI Boot Firmware Table ==
+       Microsoft defined table, support TBD.
+
+IVRS   Signature Reserved (signature == "IVRS")
+       == I/O Virtualization Reporting Structure ==
+       x86_64 (AMD) only table, will not be supported.
+
+LPIT   Signature Reserved (signature == "LPIT")
+       == Low Power Idle Table ==
+       x86 only table as of ACPI 5.1; future versions have been adapted for
+       use with ARM and will be recommended in order to support ACPI power
+       management.
+
+MADT   Section 5.2.12 (signature == "APIC")
+       == Multiple APIC Description Table ==
+       Required for arm64.  Only the GIC interrupt controller structures
+       should be used (types 0xA - 0xE).
+
+MCFG   Signature Reserved (signature == "MCFG")
+       == Memory-mapped ConFiGuration space ==
+       If the platform supports PCI/PCIe, an MCFG table is required.
+
+MCHI   Signature Reserved (signature == "MCHI")
+       == Management Controller Host Interface table ==
+       Optional, not currently supported.
+
+MPST   Section 5.2.21 (signature == "MPST")
+       == Memory Power State Table ==
+       Optional, not currently supported.
+
+MSDM   Signature Reserved (signature == "MSDM")
+       == Microsoft Data Management table ==
+       Microsoft only table, will not be supported.
+
+MSCT   Section 5.2.19 (signature == "MSCT")
+       == Maximum System Characteristic Table ==
+       Optional, not currently supported.
+
+RASF   Section 5.2.20 (signature == "RASF")
+       == RAS Feature table ==
+       Optional, not currently supported.
+
+RSDP   Section 5.2.5 (signature == "RSD PTR")
+       == Root System Description PoinTeR ==
+       Required for arm64.
+
+RSDT   Section 5.2.7 (signature == "RSDT")
+       == Root System Description Table ==
+       Since this table can only provide 32-bit addresses, it is deprecated
+       on arm64, and will not be used.
+
+SBST   Section 5.2.14 (signature == "SBST")
+       == Smart Battery Subsystem Table ==
+       Optional, not currently supported.
+
+SLIC   Signature Reserved (signature == "SLIC")
+       == Software LIcensing table ==
+       Microsoft only table, will not be supported.
+
+SLIT   Section 5.2.17 (signature == "SLIT")
+       == System Locality distance Information Table ==
+       Optional in general, but required for NUMA systems.
+
+SPCR   Signature Reserved (signature == "SPCR")
+       == Serial Port Console Redirection table ==
+       Required for arm64.
+
+SPMI   Signature Reserved (signature == "SPMI")
+       == Server Platform Management Interface table ==
+       Optional, not currently supported.
+
+SRAT   Section 5.2.16 (signature == "SRAT")
+       == System Resource Affinity Table ==
+       Optional, but if used, only the GICC Affinity structures are read.
+       To support NUMA, this table is required.
+
+SSDT   Section 5.2.11.2 (signature == "SSDT")
+       == Secondary System Description Table ==
+       These tables are a continuation of the DSDT; these are recommended
+       for use with devices that can be added to a running system, but can
+       also serve the purpose of dividing up device descriptions into more
+       manageable pieces.
+
+       An SSDT can only ADD to the ACPI namespace.  It cannot modify or
+       replace existing device descriptions already in the namespace.
+
+       These tables are optional, however.  ACPI tables should contain only
+       one DSDT but can contain many SSDTs.
+
+TCPA   Signature Reserved (signature == "TCPA")
+       == Trusted Computing Platform Alliance table ==
+       Optional, not currently supported, and may need changes to fully
+       interoperate with arm64.
+
+TPM2   Signature Reserved (signature == "TPM2")
+       == Trusted Platform Module 2 table ==
+       Optional, not currently supported, and may need changes to fully
+       interoperate with arm64.
+
+UEFI   Signature Reserved (signature == "UEFI")
+       == UEFI ACPI data table ==
+       Optional, not currently supported.  No known use case for arm64,
+       at present.
+
+WAET   Signature Reserved (signature == "WAET")
+       == Windows ACPI Emulated devices Table ==
+       Microsoft only table, will not be supported.
+
+WDAT   Signature Reserved (signature == "WDAT")
+       == Watch Dog Action Table ==
+       Microsoft only table, will not be supported.
+
+WDRT   Signature Reserved (signature == "WDRT")
+       == Watch Dog Resource Table ==
+       Microsoft only table, will not be supported.
+
+WPBT   Signature Reserved (signature == "WPBT")
+       == Windows Platform Binary Table ==
+       Microsoft only table, will not be supported.
+
+XSDT   Section 5.2.8 (signature == "XSDT")
+       == eXtended System Description Table ==
+       Required for arm64.
+
+
+ACPI Objects
+------------
+The expectations on individual ACPI objects are discussed in the list that
+follows:
+
+Name   Section         Usage for ARMv8 Linux
+----   ------------    -------------------------------------------------
+_ADR   6.1.1           Use as needed.
+
+_BBN   6.5.5           Use as needed; PCI-specific.
+
+_BDN   6.5.3           Optional; not likely to be used on arm64.
+
+_CCA   6.2.17          This method should be defined for all bus masters
+                       on arm64.  While cache coherency is assumed, making
+                       it explicit ensures the kernel will set up DMA as
+                       it should.
+
+_CDM   6.2.1           Optional, to be used only for processor devices.
+
+_CID   6.1.2           Use as needed.
+
+_CLS   6.1.3           Use as needed.
+
+_CRS   6.2.2           Required on arm64.
+
+_DCK   6.5.2           Optional; not likely to be used on arm64.
+
+_DDN   6.1.4           This field can be used for a device name.  However,
+                       it is meant for DOS device names (e.g., COM1), so be
+                       careful of its use across OSes.
+
+_DEP   6.5.8           Use as needed.
+
+_DIS   6.2.3           Optional, for power management use.
+
+_DLM   5.7.5           Optional.
+
+_DMA   6.2.4           Optional.
+
+_DSD   6.2.5           To be used with caution.  If this object is used, try
+                       to use it within the constraints already defined by the
+                       Device Properties UUID.  Only in rare circumstances
+                       should it be necessary to create a new _DSD UUID.
+
+                       In either case, submit the _DSD definition along with
+                       any driver patches for discussion, especially when
+                       device properties are used.  A driver will not be
+                       considered complete without a corresponding _DSD
+                       description.  Once approved by kernel maintainers,
+                       the UUID or device properties must then be registered
+                       with the UEFI Forum; this may cause some iteration as
+                       more than one OS will be registering entries.
+
+_DSM                   Do not use this method.  It is not standardized, the
+                       return values are not well documented, and it is
+                       currently a frequent source of error.
+
+_DSW   7.2.1           Use as needed; power management specific.
+
+_EDL   6.3.1           Optional.
+
+_EJD   6.3.2           Optional.
+
+_EJx   6.3.3           Optional.
+
+_FIX   6.2.7           x86 specific, not used on arm64.
+
+\_GL   5.7.1           This object is not to be used in hardware reduced
+                       mode, and therefore should not be used on arm64.
+
+_GLK   6.5.7           This object requires a global lock be defined; there
+                       is no global lock on arm64 since it runs in hardware
+                       reduced mode.  Hence, do not use this object on arm64.
+
+\_GPE  5.3.1           This namespace is for x86 use only.  Do not use it
+                       on arm64.
+
+_GSB   6.2.7           Optional.
+
+_HID   6.1.5           Use as needed.  This is the primary object to use in
+                       device probing, though _CID and _CLS may also be used.
+
+_HPP   6.2.8           Optional, PCI specific.
+
+_HPX   6.2.9           Optional, PCI specific.
+
+_HRV   6.1.6           Optional, use as needed to clarify device behavior; in
+                       some cases, this may be easier to use than _DSD.
+
+_INI   6.5.1           Not required, but can be useful in setting up devices
+                       when UEFI leaves them in a state that may not be what
+                       the driver expects before it starts probing.
+
+_IRC   7.2.15          Use as needed; power management specific.
+
+_LCK   6.3.4           Optional.
+
+_MAT   6.2.10          Optional; see also the MADT.
+
+_MLS   6.1.7           Optional, but highly recommended for use in
+                       internationalization.
+
+_OFF   7.1.2           It is recommended to define this method for any device
+                       that can be turned on or off.
+
+_ON    7.1.3           It is recommended to define this method for any device
+                       that can be turned on or off.
+
+\_OS   5.7.3           This method will return "Linux" by default (this is
+                       the value of the macro ACPI_OS_NAME on Linux).  The
+                       command line parameter acpi_os=<string> can be used
+                       to set it to some other value.
+
+_OSC   6.2.11          This method can be a global method in ACPI (i.e.,
+                       \_SB._OSC), or it may be associated with a specific
+                       device (e.g., \_SB.DEV0._OSC), or both.  When used
+                       as a global method, only capabilities published in
+                       the ACPI specification are allowed.  When used as
+                       a device-specific method, the process described for
+                       using _DSD MUST be used to create an _OSC definition;
+                       out-of-process use of _OSC is not allowed.  That is,
+                       submit the device-specific _OSC usage description as
+                       part of the kernel driver submission, get it approved
+                       by the kernel community, then register it with the
+                       UEFI Forum.
+
+\_OSI  5.7.2           Deprecated on ARM64.  Any invocation of this method
+                       will print a warning on the console and return false.
+                       That is, as far as ACPI firmware is concerned, _OSI
+                       cannot be used to determine what sort of system is
+                       being used or what functionality is provided.  The
+                       _OSC method is to be used instead.
+
+_OST   6.3.5           Optional.
+
+_PDC   8.4.1           Deprecated, do not use on arm64.
+
+\_PIC  5.8.1           The method should not be used.  On arm64, the only
+                       interrupt model available is GIC.
+
+_PLD   6.1.8           Optional.
+
+\_PR   5.3.1           This namespace is for x86 use only on legacy systems.
+                       Do not use it on arm64.
+
+_PRS   6.2.12          Optional.
+
+_PRT   6.2.13          Required as part of the definition of all PCI root
+                       devices.
+
+_PRW   7.2.13          Use as needed; power management specific.
+
+_PRx   7.2.8-11        Use as needed; power management specific.  If _PR0 is
+                       defined, _PR3 must also be defined.
+
+_PSC   7.2.6           Use as needed; power management specific.
+
+_PSE   7.2.7           Use as needed; power management specific.
+
+_PSW   7.2.14          Use as needed; power management specific.
+
+_PSx   7.2.2-5         Use as needed; power management specific.  If _PS0 is
+                       defined, _PS3 must also be defined.  If clocks or
+                       regulators need adjusting to be consistent with power
+                       usage, change them in these methods.
+
+\_PTS  7.3.1           Use as needed; power management specific.
+
+_PXM   6.2.14          Optional.
+
+_REG   6.5.4           Use as needed.
+
+\_REV  5.7.4           Always returns the latest version of ACPI supported.
+
+_RMV   6.3.6           Optional.
+
+\_SB   5.3.1           Required on arm64; all devices must be defined in this
+                       namespace.
+
+_SEG   6.5.6           Use as needed; PCI-specific.
+
+\_SI   5.3.1,          Optional.
+       9.1
+
+_SLI   6.2.15          Optional; recommended when SLIT table is in use.
+
+_STA   6.3.7,          It is recommended to define this method for any device
+       7.1.4           that can be turned on or off.
+
+_SRS   6.2.16          Optional; see also _PRS.
+
+_STR   6.1.10          Recommended for conveying device names to end users;
+                       this is preferred over using _DDN.
+
+_SUB   6.1.9           Use as needed; _HID or _CID are preferred.
+
+_SUN   6.1.11          Optional.
+
+\_Sx   7.3.2           Use as needed; power management specific.
+
+_SxD   7.2.16-19       Use as needed; power management specific.
+
+_SxW   7.2.20-24       Use as needed; power management specific.
+
+_SWS   7.3.3           Use as needed; power management specific; this may
+                       require specification changes for use on arm64.
+
+\_TTS  7.3.4           Use as needed; power management specific.
+
+\_TZ   5.3.1           Optional.
+
+_UID   6.1.12          Recommended for distinguishing devices of the same
+                       class; define it if at all possible.
+
+\_WAK  7.3.5           Use as needed; power management specific.
+
+
+ACPI Event Model
+----------------
+Do not use GPE block devices; these are not supported in the hardware reduced
+profile used by arm64.  Since there are no GPE blocks defined for use on ARM
+platforms, GPIO-signaled interrupts should be used for creating system events.
+
+
+ACPI Processor Control
+----------------------
+Section 8 of the ACPI specification is currently undergoing change that
+should be completed in the 6.0 version of the specification.  Processor
+performance control will be handled differently for arm64 at that point
+in time.  Processor aggregator devices (section 8.5) will not be used,
+for example, but another similar mechanism instead.
+
+While UEFI constrains what we can say until the release of 6.0, it is
+recommended that CPPC (8.4.5) be used as the primary model.  This will
+still be useful into the future.  C-states and P-states will still be
+provided, but most of the current design work appears to favor CPPC.
+
+Further, it is essential that the ARMv8 SoC provide a fully functional
+implementation of PSCI; this will be the only mechanism supported by ACPI
+to control CPU power state (including secondary CPU booting).
+
+More details will be provided on the release of the ACPI 6.0 specification.
+
+
+ACPI System Address Map Interfaces
+----------------------------------
+In Section 15 of the ACPI specification, several methods are mentioned as
+possible mechanisms for conveying memory resource information to the kernel.
+For arm64, we will only support UEFI for booting with ACPI, hence the UEFI
+GetMemoryMap() boot service is the only mechanism that will be used.
+
+
+ACPI Platform Error Interfaces (APEI)
+-------------------------------------
+The APEI tables supported are described above.
+
+APEI requires the equivalent of an SCI and an NMI on ARMv8.  The SCI is used
+to notify the OSPM of errors that have occurred but can be corrected and the
+system can continue correct operation, even if possibly degraded.  The NMI is
+used to indicate fatal errors that cannot be corrected, and require immediate
+attention.
+
+Since there is no direct equivalent of the x86 SCI or NMI, arm64 handles
+these slightly differently.  The SCI is handled as a normal GPIO-signaled
+interrupt; given that these are corrected (or correctable) errors being
+reported, this is sufficient.  The NMI is emulated as the highest priority
+GPIO-signaled interrupt possible.  This implies some caution must be used
+since there could be interrupts at higher privilege levels or even interrupts
+at the same priority as the emulated NMI.  In Linux, this should not be the
+case but one should be aware it could happen.
+
+
+ACPI Objects Not Supported on ARM64
+-----------------------------------
+While this may change in the future, there are several classes of objects
+that can be defined, but are not currently of general interest to ARM servers.
+
+These are not supported:
+
+       -- Section 9.2: ambient light sensor devices
+
+       -- Section 9.3: battery devices
+
+       -- Section 9.4: lids (e.g., laptop lids)
+
+       -- Section 9.8.2: IDE controllers
+
+       -- Section 9.9: floppy controllers
+
+       -- Section 9.10: GPE block devices
+
+       -- Section 9.15: PC/AT RTC/CMOS devices
+
+       -- Section 9.16: user presence detection devices
+
+       -- Section 9.17: I/O APIC devices; all GICs must be enumerable via MADT
+
+       -- Section 9.18: time and alarm devices (see 9.15)
+
+
+ACPI Objects Not Yet Implemented
+--------------------------------
+While these objects have x86 equivalents, and they do make some sense in ARM
+servers, there is either no hardware available at present, or in some cases
+there may not yet be a non-ARM implementation.  Hence, they are currently not
+implemented though that may change in the future.
+
+Not yet implemented are:
+
+       -- Section 10: power source and power meter devices
+
+       -- Section 11: thermal management
+
+       -- Section 12: embedded controllers interface
+
+       -- Section 13: SMBus interfaces
+
+       -- Section 17: NUMA support (prototypes have been submitted for
+          review)
diff --git a/Documentation/arm64/arm-acpi.txt b/Documentation/arm64/arm-acpi.txt
new file mode 100644
index 000000000000..570a4f8e1a01
--- /dev/null
+++ b/Documentation/arm64/arm-acpi.txt
@@ -0,0 +1,505 @@
+ACPI on ARMv8 Servers
+---------------------
+ACPI can be used for ARMv8 general purpose servers designed to follow
+the ARM SBSA (Server Base System Architecture) [0] and SBBR (Server
+Base Boot Requirements) [1] specifications.  Please note that the SBBR
+can be retrieved simply by visiting [1], but the SBSA is currently only
+available to those with an ARM login due to ARM IP licensing concerns.
+
+The ARMv8 kernel implements the reduced hardware model of ACPI version
+5.1 or later.  Links to the specification and all external documents
+it refers to are managed by the UEFI Forum.  The specification is
+available at http://www.uefi.org/specifications and documents referenced
+by the specification can be found via http://www.uefi.org/acpi.
+
+If an ARMv8 system does not meet the requirements of the SBSA and SBBR,
+or cannot be described using the mechanisms defined in the required ACPI
+specifications, then ACPI may not be a good fit for the hardware.
+
+While the documents mentioned above set out the requirements for building
+industry-standard ARMv8 servers, they also apply to more than one operating
+system.  The purpose of this document is to describe the interaction between
+ACPI and Linux only, on an ARMv8 system -- that is, what Linux expects of
+ACPI and what ACPI can expect of Linux.
+
+
+Why ACPI on ARM?
+----------------
+Before examining the details of the interface between ACPI and Linux, it is
+useful to understand why ACPI is being used.  Several technologies already
+exist in Linux for describing non-enumerable hardware, after all.  In this
+section we summarize a blog post [2] from Grant Likely that outlines the
+reasoning behind ACPI on ARMv8 servers.  Actually, we snitch a good portion
+of the summary text almost directly, to be honest.
+
+The short form of the rationale for ACPI on ARM is:
+
+-- ACPI’s bytecode (AML) allows the platform to encode hardware behavior,
+   while DT explicitly does not support this.  For hardware vendors, being
+   able to encode behavior is a key tool used in supporting operating
+   system releases on new hardware.
+
+-- ACPI’s OSPM defines a power management model that constrains what the
+   platform is allowed to do into a specific model, while still providing
+   flexibility in hardware design.
+
+-- In the enterprise server environment, ACPI has established bindings (such
+   as for RAS) which are currently used in production systems.  DT does not.
+   Such bindings could be defined in DT at some point, but doing so means ARM
+   and x86 would end up using completely different code paths in both firmware
+   and the kernel.
+
+-- Choosing a single interface to describe the abstraction between a platform
+   and an OS is important.  Hardware vendors would not be required to implement
+   both DT and ACPI if they want to support multiple operating systems.  And,
+   agreeing on a single interface instead of being fragmented into per OS
+   interfaces makes for better interoperability overall.
+
+-- The new ACPI governance process works well and Linux is now at the same
+   table as hardware vendors and other OS vendors.  In fact, there is no
+   longer any reason to feel that ACPI is only belongs to Windows or that
+   Linux is in any way secondary to Microsoft in this arena.  The move of
+   ACPI governance into the UEFI forum has significantly opened up the
+   specification development process, and currently, a large portion of the
+   changes being made to ACPI is being driven by Linux.
+
+Key to the use of ACPI is the support model.  For servers in general, the
+responsibility for hardware behaviour cannot solely be the domain of the
+kernel, but rather must be split between the platform and the kernel, in
+order to allow for orderly change over time.  ACPI frees the OS from needing
+to understand all the minute details of the hardware so that the OS doesn’t
+need to be ported to each and every device individually.  It allows the
+hardware vendors to take responsibility for power management behaviour without
+depending on an OS release cycle which is not under their control.
+
+ACPI is also important because hardware and OS vendors have already worked
+out the mechanisms for supporting a general purpose computing ecosystem.  The
+infrastructure is in place, the bindings are in place, and the processes are
+in place.  DT does exactly what Linux needs it to when working with vertically
+integrated devices, but there are no good processes for supporting what the
+server vendors need.  Linux could potentially get there with DT, but doing so
+really just duplicates something that already works.  ACPI already does what
+the hardware vendors need, Microsoft won’t collaborate on DT, and hardware
+vendors would still end up providing two completely separate firmware
+interfaces -- one for Linux and one for Windows.
+
+
+Kernel Compatibility
+--------------------
+One of the primary motivations for ACPI is standardization, and using that
+to provide backward compatibility for Linux kernels.  In the server market,
+software and hardware are often used for long periods.  ACPI allows the
+kernel and firmware to agree on a consistent abstraction that can be
+maintained over time, even as hardware or software change.  As long as the
+abstraction is supported, systems can be updated without necessarily having
+to replace the kernel.
+
+When a Linux driver or subsystem is first implemented using ACPI, it by
+definition ends up requiring a specific version of the ACPI specification
+-- it's baseline.  ACPI firmware must continue to work, even though it may
+not be optimal, with the earliest kernel version that first provides support
+for that baseline version of ACPI.  There may be a need for additional drivers,
+but adding new functionality (e.g., CPU power management) should not break
+older kernel versions.  Further, ACPI firmware must also work with the most
+recent version of the kernel.
+
+
+Relationship with Device Tree
+-----------------------------
+ACPI support in drivers and subsystems for ARMv8 should never be mutually
+exclusive with DT support at compile time.
+
+At boot time the kernel will only use one description method depending on
+parameters passed from the bootloader (including kernel bootargs).
+
+Regardless of whether DT or ACPI is used, the kernel must always be capable
+of booting with either scheme (in kernels with both schemes enabled at compile
+time).
+
+
+Booting using ACPI tables
+-------------------------
+The only defined method for passing ACPI tables to the kernel on ARMv8
+is via the UEFI system configuration table.  Just so it is explicit, this
+means that ACPI is only supported on platforms that boot via UEFI.
+
+When an ARMv8 system boots, it can either have DT information, ACPI tables,
+or in some very unusual cases, both.  If no command line parameters are used,
+the kernel will try to use DT for device enumeration; if there is no DT
+present, the kernel will try to use ACPI tables, but only if they are present.
+In neither is available, the kernel will not boot.  If acpi=force is used
+on the command line, the kernel will attempt to use ACPI tables first, but
+fall back to DT if there are no ACPI tables present.  The basic idea is that
+the kernel will not fail to boot unless it absolutely has no other choice.
+
+Processing of ACPI tables may be disabled by passing acpi=off on the kernel
+command line; this is the default behavior.
+
+In order for the kernel to load and use ACPI tables, the UEFI implementation
+MUST set the ACPI_20_TABLE_GUID to point to the RSDP table (the table with
+the ACPI signature "RSD PTR ").  If this pointer is incorrect and acpi=force
+is used, the kernel will disable ACPI and try to use DT to boot instead; the
+kernel has, in effect, determined that ACPI tables are not present at that
+point.
+
+If the pointer to the RSDP table is correct, the table will be mapped into
+the kernel by the ACPI core, using the address provided by UEFI.
+
+The ACPI core will then locate and map in all other ACPI tables provided by
+using the addresses in the RSDP table to find the XSDT (eXtended System
+Description Table).  The XSDT in turn provides the addresses to all other
+ACPI tables provided by the system firmware; the ACPI core will then traverse
+this table and map in the tables listed.
+
+The ACPI core will ignore any provided RSDT (Root System Description Table).
+RSDTs have been deprecated and are ignored on arm64 since they only allow
+for 32-bit addresses.
+
+Further, the ACPI core will only use the 64-bit address fields in the FADT
+(Fixed ACPI Description Table).  Any 32-bit address fields in the FADT will
+be ignored on arm64.
+
+Hardware reduced mode (see Section 4.1 of the ACPI 5.1 specification) will
+be enforced by the ACPI core on arm64.  Doing so allows the ACPI core to
+run less complex code since it no longer has to provide support for legacy
+hardware from other architectures.  Any fields that are not to be used for
+hardware reduced mode must be set to zero.
+
+For the ACPI core to operate properly, and in turn provide the information
+the kernel needs to configure devices, it expects to find the following
+tables (all section numbers refer to the ACPI 5.1 specfication):
+
+    -- RSDP (Root System Description Pointer), section 5.2.5
+
+    -- XSDT (eXtended System Description Table), section 5.2.8
+
+    -- FADT (Fixed ACPI Description Table), section 5.2.9
+
+    -- DSDT (Differentiated System Description Table), section
+       5.2.11.1
+
+    -- MADT (Multiple APIC Description Table), section 5.2.12
+
+    -- GTDT (Generic Timer Description Table), section 5.2.24
+
+    -- If PCI is supported, the MCFG (Memory mapped ConFiGuration
+       Table), section 5.2.6, specifically Table 5-31.
+
+If the above tables are not all present, the kernel may or may not be
+able to boot properly since it may not be able to configure all of the
+devices available.
+
+
+ACPI Detection
+--------------
+Drivers should determine their probe() type by checking for a null
+value for ACPI_HANDLE, or checking .of_node, or other information in
+the device structure.  This is detailed further in the "Driver
+Recommendations" section.
+
+In non-driver code, if the presence of ACPI needs to be detected at
+runtime, then check the value of acpi_disabled. If CONFIG_ACPI is not
+set, acpi_disabled will always be 1.
+
+
+Device Enumeration
+------------------
+Device descriptions in ACPI should use standard recognized ACPI interfaces.
+These may contain less information than is typically provided via a Device
+Tree description for the same device.  This is also one of the reasons that
+ACPI can be useful -- the driver takes into account that it may have less
+detailed information about the device and uses sensible defaults instead.
+If done properly in the driver, the hardware can change and improve over
+time without the driver having to change at all.
+
+Clocks provide an excellent example.  In DT, clocks need to be specified
+and the drivers need to take them into account.  In ACPI, the assumption
+is that UEFI will leave the device in a reasonable default state, including
+any clock settings.  If for some reason the driver needs to change a clock
+value, this can be done in an ACPI method; all the driver needs to do is
+invoke the method and not concern itself with what the method needs to do
+to change the clock.  Changing the hardware can then take place over time
+by changing what the ACPI method does, and not the driver.
+
+In DT, the parameters needed by the driver to set up clocks as in the example
+above are known as "bindings"; in ACPI, these are known as "Device Properties"
+and provided to a driver via the _DSD object.
+
+ACPI tables are described with a formal language called ASL, the ACPI
+Source Language (section 19 of the specification).  This means that there
+are always multiple ways to describe the same thing -- including device
+properties.  For example, device properties could use an ASL construct
+that looks like this: Name(KEY0, "value0").  An ACPI device driver would
+then retrieve the value of the property by evaluating the KEY0 object.
+However, using Name() this way has multiple problems: (1) ACPI limits
+names ("KEY0") to four characters unlike DT; (2) there is no industry
+wide registry that maintains a list of names, minimzing re-use; (3)
+there is also no registry for the definition of property values ("value0"),
+again making re-use difficult; and (4) how does one maintain backward
+compatibility as new hardware comes out?  The _DSD method was created
+to solve precisely these sorts of problems; Linux drivers should ALWAYS
+use the _DSD method for device properties and nothing else.
+
+The _DSM object (ACPI Section 9.14.1) could also be used for conveying
+device properties to a driver.  Linux drivers should only expect it to
+be used if _DSD cannot represent the data required, and there is no way
+to create a new UUID for the _DSD object.  Note that there is even less
+regulation of the use of _DSM than there is of _DSD.  Drivers that depend
+on the contents of _DSM objects will be more difficult to maintain over
+time because of this; as of this writing, the use of _DSM is the cause
+of quite a few firmware problems and is not recommended.
+
+Drivers should look for device properties in the _DSD object ONLY; the _DSD
+object is described in the ACPI specification section 6.2.5, but this only
+describes how to define the structure of an object returned via _DSD, and
+how specific data structures are defined by specific UUIDs.  Linux should
+only use the _DSD Device Properties UUID [5]:
+
+   -- UUID: daffd814-6eba-4d8c-8a91-bc9bbf4aa301
+
+   -- http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf
+
+The UEFI Forum provides a mechanism for registering device properties [4]
+so that they may be used across all operating systems supporting ACPI.
+Device properties that have not been registered with the UEFI Forum should
+not be used.
+
+Before creating new device properties, check to be sure that they have not
+been defined before and either registered in the Linux kernel documentation
+as DT bindings, or the UEFI Forum as device properties.  While we do not want
+to simply move all DT bindings into ACPI device properties, we can learn from
+what has been previously defined.
+
+If it is necessary to define a new device property, or if it makes sense to
+synthesize the definition of a binding so it can be used in any firmware,
+both DT bindings and ACPI device properties for device drivers have review
+processes.  Use them both.  When the driver itself is submitted for review
+to the Linux mailing lists, the device property definitions needed must be
+submitted at the same time.  A driver that supports ACPI and uses device
+properties will not be considered complete without their definitions.  Once
+the device property has been accepted by the Linux community, it must be
+registered with the UEFI Forum [4], which will review it again for consistency
+within the registry.  This may require iteration.  The UEFI Forum, though,
+will always be the canonical site for device property definitions.
+
+It may make sense to provide notice to the UEFI Forum that there is the
+intent to register a previously unused device property name as a means of
+reserving the name for later use.  Other operating system vendors will
+also be submitting registration requests and this may help smooth the
+process.
+
+Once registration and review have been completed, the kernel provides an
+interface for looking up device properties in a manner independent of
+whether DT or ACPI is being used.  This API should be used [6]; it can
+eliminate some duplication of code paths in driver probing functions and
+discourage divergence between DT bindings and ACPI device properties.
+
+
+Programmable Power Control Resources
+------------------------------------
+Programmable power control resources include such resources as voltage/current
+providers (regulators) and clock sources.
+
+With ACPI, the kernel clock and regulator framework is not expected to be used
+at all.
+
+The kernel assumes that power control of these resources is represented with
+Power Resource Objects (ACPI section 7.1).  The ACPI core will then handle
+correctly enabling and disabling resources as they are needed.  In order to
+get that to work, ACPI assumes each device has defined D-states and that these
+can be controlled through the optional ACPI methods _PS0, _PS1, _PS2, and _PS3;
+in ACPI, _PS0 is the method to invoke to turn a device full on, and _PS3 is for
+turning a device full off.
+
+There are two options for using those Power Resources.  They can:
+
+   -- be managed in a _PSx method which gets called on entry to power
+      state Dx.
+
+   -- be declared separately as power resources with their own _ON and _OFF
+      methods.  They are then tied back to D-states for a particular device
+      via _PRx which specifies which power resources a device needs to be on
+      while in Dx.  Kernel then tracks number of devices using a power resource
+      and calls _ON/_OFF as needed.
+
+The kernel ACPI code will also assume that the _PSx methods follow the normal
+ACPI rules for such methods:
+
+   -- If either _PS0 or _PS3 is implemented, then the other method must also
+      be implemented.
+
+   -- If a device requires usage or setup of a power resource when on, the ASL
+      should organize that it is allocated/enabled using the _PS0 method.
+
+   -- Resources allocated or enabled in the _PS0 method should be disabled
+      or de-allocated in the _PS3 method.
+
+   -- Firmware will leave the resources in a reasonable state before handing
+      over control to the kernel.
+
+Such code in _PSx methods will of course be very platform specific.  But,
+this allows the driver to abstract out the interface for operating the device
+and avoid having to read special non-standard values from ACPI tables. Further,
+abstracting the use of these resources allows the hardware to change over time
+without requiring updates to the driver.
+
+
+Clocks
+------
+ACPI makes the assumption that clocks are initialized by the firmware --
+UEFI, in this case -- to some working value before control is handed over
+to the kernel.  This has implications for devices such as UARTs, or SoC-driven
+LCD displays, for example.
+
+When the kernel boots, the clocks are assumed to be set to reasonable
+working values.  If for some reason the frequency needs to change -- e.g.,
+throttling for power management -- the device driver should expect that
+process to be abstracted out into some ACPI method that can be invoked
+(please see the ACPI specification for further recommendations on standard
+methods to be expected).  The only exceptions to this are CPU clocks where
+CPPC provides a much richer interface than ACPI methods.  If the clocks
+are not set, there is no direct way for Linux to control them.
+
+If an SoC vendor wants to provide fine-grained control of the system clocks,
+they could do so by providing ACPI methods that could be invoked by Linux
+drivers.  However, this is NOT recommended and Linux drivers should NOT use
+such methods, even if they are provided.  Such methods are not currently
+standardized in the ACPI specification, and using them could tie a kernel
+to a very specific SoC, or tie an SoC to a very specific version of the
+kernel, both of which we are trying to avoid.
+
+
+Driver Recommendations
+----------------------
+DO NOT remove any DT handling when adding ACPI support for a driver.  The
+same device may be used on many different systems.
+
+DO try to structure the driver so that it is data-driven.  That is, set up
+a struct containing internal per-device state based on defaults and whatever
+else must be discovered by the driver probe function.  Then, have the rest
+of the driver operate off of the contents of that struct.  Doing so should
+allow most divergence between ACPI and DT functionality to be kept local to
+the probe function instead of being scattered throughout the driver.  For
+example:
+
+static int device_probe_dt(struct platform_device *pdev)
+{
+       /* DT specific functionality */
+       ...
+}
+
+static int device_probe_acpi(struct platform_device *pdev)
+{
+       /* ACPI specific functionality */
+       ...
+}
+
+static int device_probe(struct platform_device *pdev)
+{
+       ...
+       struct device_node node = pdev->dev.of_node;
+       ...
+
+       if (node)
+               ret = device_probe_dt(pdev);
+       else if (ACPI_HANDLE(&pdev->dev))
+               ret = device_probe_acpi(pdev);
+       else
+               /* other initialization */
+               ...
+       /* Continue with any generic probe operations */
+       ...
+}
+
+DO keep the MODULE_DEVICE_TABLE entries together in the driver to make it
+clear the different names the driver is probed for, both from DT and from
+ACPI:
+
+static struct of_device_id virtio_mmio_match[] = {
+        { .compatible = "virtio,mmio", },
+        { }
+};
+MODULE_DEVICE_TABLE(of, virtio_mmio_match);
+
+static const struct acpi_device_id virtio_mmio_acpi_match[] = {
+        { "LNRO0005", },
+        { }
+};
+MODULE_DEVICE_TABLE(acpi, virtio_mmio_acpi_match);
+
+
+ASWG
+----
+The ACPI specification changes regularly.  During the year 2014, for instance,
+version 5.1 was released and version 6.0 substantially completed, with most of
+the changes being driven by ARM-specific requirements.  Proposed changes are
+presented and discussed in the ASWG (ACPI Specification Working Group) which
+is a part of the UEFI Forum.
+
+Participation in this group is open to all UEFI members.  Please see
+http://www.uefi.org/workinggroup for details on group membership.
+
+It is the intent of the ARMv8 ACPI kernel code to follow the ACPI specification
+as closely as possible, and to only implement functionality that complies with
+the released standards from UEFI ASWG.  As a practical matter, there will be
+vendors that provide bad ACPI tables or violate the standards in some way.
+If this is because of errors, quirks and fixups may be necessary, but will
+be avoided if possible.  If there are features missing from ACPI that preclude
+it from being used on a platform, ECRs (Engineering Change Requests) should be
+submitted to ASWG and go through the normal approval process; for those that
+are not UEFI members, many other members of the Linux community are and would
+likely be willing to assist in submitting ECRs.
+
+
+Linux Code
+----------
+Individual items specific to Linux on ARM, contained in the the Linux
+source code, are in the list that follows:
+
+ACPI_OS_NAME           This macro defines the string to be returned when
+                       an ACPI method invokes the _OS method.  On ARM64
+                       systems, this macro will be "Linux" by default.
+                       The command line parameter acpi_os=<string>
+                       can be used to set it to some other value.  The
+                       default value for other architectures is "Microsoft
+                       Windows NT", for example.
+
+ACPI Objects
+------------
+Detailed expectations for ACPI tables and object are listed in the file
+Documentation/arm64/acpi_object_usage.txt.
+
+
+References
+----------
+[0] http://silver.arm.com -- document ARM-DEN-0029, or newer
+    "Server Base System Architecture", version 2.3, dated 27 Mar 2014
+
+[1] http://infocenter.arm.com/help/topic/com.arm.doc.den0044a/Server_Base_Boot_Requirements.pdf
+    Document ARM-DEN-0044A, or newer: "Server Base Boot Requirements, System
+    Software on ARM Platforms", dated 16 Aug 2014
+
+[2] http://www.secretlab.ca/archives/151, 10 Jan 2015, Copyright (c) 2015,
+    Linaro Ltd., written by Grant Likely.  A copy of the verbatim text (apart
+    from formatting) is also in Documentation/arm64/why_use_acpi.txt.
+
+[3] AMD ACPI for Seattle platform documentation:
+    http://amd-dev.wpengine.netdna-cdn.com/wordpress/media/2012/10/Seattle_ACPI_Guide.pdf
+
+[4] http://www.uefi.org/acpi -- please see the link for the "ACPI _DSD Device
+    Property Registry Instructions"
+
+[5] http://www.uefi.org/acpi -- please see the link for the "_DSD (Device
+    Specific Data) Implementation Guide"
+
+[6] Kernel code for the unified device property interface can be found in
+    include/linux/property.h and drivers/base/property.c.
+
+
+Authors
+-------
+Al Stone <al.stone@linaro.org>
+Graeme Gregory <graeme.gregory@linaro.org>
+Hanjun Guo <hanjun.guo@linaro.org>
+
+Grant Likely <grant.likely@linaro.org>, for the "Why ACPI on ARM?" section
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 84960c66c77b..f6befa9855c1 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -165,7 +165,7 @@ multipliers 'Kilo', 'Mega', and 'Giga', equalling 2^10, 2^20, and 2^30
 bytes respectively. Such letter suffixes can also be entirely omitted.
 
 
-	acpi=		[HW,ACPI,X86]
+	acpi=		[HW,ACPI,X86,ARM64]
 			Advanced Configuration and Power Interface
 			Format: { force | off | strict | noirq | rsdt }
 			force -- enable ACPI if default was off
@@ -175,6 +175,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 				strictly ACPI specification compliant.
 			rsdt -- prefer RSDT over (default) XSDT
 			copy_dsdt -- copy DSDT to memory
+			For ARM64, ONLY "acpi=off" or "acpi=force" are available
 
 			See also Documentation/power/runtime_pm.txt, pci=noacpi
 
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index da5f20e8cc50..4269dba63cf1 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1,5 +1,7 @@
 config ARM64
 	def_bool y
+	select ACPI_GENERIC_GSI if ACPI
+	select ACPI_REDUCED_HARDWARE_ONLY if ACPI
 	select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
 	select ARCH_HAS_ELF_RANDOMIZE
 	select ARCH_HAS_GCOV_PROFILE_ALL
@@ -758,6 +760,8 @@ source "drivers/Kconfig"
 
 source "drivers/firmware/Kconfig"
 
+source "drivers/acpi/Kconfig"
+
 source "fs/Kconfig"
 
 source "arch/arm64/kvm/Kconfig"
diff --git a/arch/arm64/include/asm/acenv.h b/arch/arm64/include/asm/acenv.h
new file mode 100644
index 000000000000..b49166fde7ea
--- /dev/null
+++ b/arch/arm64/include/asm/acenv.h
@@ -0,0 +1,18 @@
+/*
+ * ARM64 specific ACPICA environments and implementation
+ *
+ * Copyright (C) 2014, Linaro Ltd.
+ *   Author: Hanjun Guo <hanjun.guo@linaro.org>
+ *   Author: Graeme Gregory <graeme.gregory@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_ACENV_H
+#define _ASM_ACENV_H
+
+/* It is required unconditionally by ACPI core, update it when needed. */
+
+#endif /* _ASM_ACENV_H */
diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h
new file mode 100644
index 000000000000..59c05d8ea4a0
--- /dev/null
+++ b/arch/arm64/include/asm/acpi.h
@@ -0,0 +1,96 @@
+/*
+ *  Copyright (C) 2013-2014, Linaro Ltd.
+ *	Author: Al Stone <al.stone@linaro.org>
+ *	Author: Graeme Gregory <graeme.gregory@linaro.org>
+ *	Author: Hanjun Guo <hanjun.guo@linaro.org>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation;
+ */
+
+#ifndef _ASM_ACPI_H
+#define _ASM_ACPI_H
+
+#include <linux/mm.h>
+#include <linux/irqchip/arm-gic-acpi.h>
+
+#include <asm/cputype.h>
+#include <asm/smp_plat.h>
+
+/* Basic configuration for ACPI */
+#ifdef	CONFIG_ACPI
+/* ACPI table mapping after acpi_gbl_permanent_mmap is set */
+static inline void __iomem *acpi_os_ioremap(acpi_physical_address phys,
+					    acpi_size size)
+{
+	if (!page_is_ram(phys >> PAGE_SHIFT))
+		return ioremap(phys, size);
+
+	return ioremap_cache(phys, size);
+}
+#define acpi_os_ioremap acpi_os_ioremap
+
+typedef u64 phys_cpuid_t;
+#define PHYS_CPUID_INVALID INVALID_HWID
+
+#define acpi_strict 1	/* No out-of-spec workarounds on ARM64 */
+extern int acpi_disabled;
+extern int acpi_noirq;
+extern int acpi_pci_disabled;
+
+/* 1 to indicate PSCI 0.2+ is implemented */
+static inline bool acpi_psci_present(void)
+{
+	return acpi_gbl_FADT.arm_boot_flags & ACPI_FADT_PSCI_COMPLIANT;
+}
+
+/* 1 to indicate HVC must be used instead of SMC as the PSCI conduit */
+static inline bool acpi_psci_use_hvc(void)
+{
+	return acpi_gbl_FADT.arm_boot_flags & ACPI_FADT_PSCI_USE_HVC;
+}
+
+static inline void disable_acpi(void)
+{
+	acpi_disabled = 1;
+	acpi_pci_disabled = 1;
+	acpi_noirq = 1;
+}
+
+static inline void enable_acpi(void)
+{
+	acpi_disabled = 0;
+	acpi_pci_disabled = 0;
+	acpi_noirq = 0;
+}
+
+/*
+ * The ACPI processor driver for ACPI core code needs this macro
+ * to find out this cpu was already mapped (mapping from CPU hardware
+ * ID to CPU logical ID) or not.
+ */
+#define cpu_physical_id(cpu) cpu_logical_map(cpu)
+
+/*
+ * It's used from ACPI core in kdump to boot UP system with SMP kernel,
+ * with this check the ACPI core will not override the CPU index
+ * obtained from GICC with 0 and not print some error message as well.
+ * Since MADT must provide at least one GICC structure for GIC
+ * initialization, CPU will be always available in MADT on ARM64.
+ */
+static inline bool acpi_has_cpu_in_madt(void)
+{
+	return true;
+}
+
+static inline void arch_fix_phys_package_id(int num, u32 slot) { }
+void __init acpi_init_cpus(void);
+
+#else
+static inline bool acpi_psci_present(void) { return false; }
+static inline bool acpi_psci_use_hvc(void) { return false; }
+static inline void acpi_init_cpus(void) { }
+#endif /* CONFIG_ACPI */
+
+#endif /*_ASM_ACPI_H*/
diff --git a/arch/arm64/include/asm/cpu_ops.h b/arch/arm64/include/asm/cpu_ops.h
index da301ee7395c..5a31d6716914 100644
--- a/arch/arm64/include/asm/cpu_ops.h
+++ b/arch/arm64/include/asm/cpu_ops.h
@@ -66,5 +66,6 @@ struct cpu_operations {
 extern const struct cpu_operations *cpu_ops[NR_CPUS];
 int __init cpu_read_ops(struct device_node *dn, int cpu);
 void __init cpu_read_bootcpu_ops(void);
+const struct cpu_operations *cpu_get_ops(const char *name);
 
 #endif /* ifndef __ASM_CPU_OPS_H */
diff --git a/arch/arm64/include/asm/fixmap.h b/arch/arm64/include/asm/fixmap.h
index 926495686554..95e6b6dcbe37 100644
--- a/arch/arm64/include/asm/fixmap.h
+++ b/arch/arm64/include/asm/fixmap.h
@@ -62,6 +62,9 @@ void __init early_fixmap_init(void);
 
 #define __early_set_fixmap __set_fixmap
 
+#define __late_set_fixmap __set_fixmap
+#define __late_clear_fixmap(idx) __set_fixmap((idx), 0, FIXMAP_PAGE_CLEAR)
+
 extern void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot);
 
 #include <asm-generic/fixmap.h>
diff --git a/arch/arm64/include/asm/irq.h b/arch/arm64/include/asm/irq.h
index 94c53674a31d..bbb251b14746 100644
--- a/arch/arm64/include/asm/irq.h
+++ b/arch/arm64/include/asm/irq.h
@@ -1,6 +1,8 @@
 #ifndef __ASM_IRQ_H
 #define __ASM_IRQ_H
 
+#include <linux/irqchip/arm-gic-acpi.h>
+
 #include <asm-generic/irq.h>
 
 struct pt_regs;
@@ -8,4 +10,15 @@ struct pt_regs;
 extern void migrate_irqs(void);
 extern void set_handle_irq(void (*handle_irq)(struct pt_regs *));
 
+static inline void acpi_irq_init(void)
+{
+	/*
+	 * Hardcode ACPI IRQ chip initialization to GICv2 for now.
+	 * Proper irqchip infrastructure will be implemented along with
+	 * incoming  GICv2m|GICv3|ITS bits.
+	 */
+	acpi_gic_init();
+}
+#define acpi_irq_init acpi_irq_init
+
 #endif
diff --git a/arch/arm64/include/asm/pci.h b/arch/arm64/include/asm/pci.h
index 872ba939fcb2..b008a72f8bc0 100644
--- a/arch/arm64/include/asm/pci.h
+++ b/arch/arm64/include/asm/pci.h
@@ -27,6 +27,12 @@
 extern int isa_dma_bridge_buggy;
 
 #ifdef CONFIG_PCI
+static inline int pci_get_legacy_ide_irq(struct pci_dev *dev, int channel)
+{
+	/* no legacy IRQ on arm64 */
+	return -ENODEV;
+}
+
 static inline int pci_proc_domain(struct pci_bus *bus)
 {
 	return 1;
diff --git a/arch/arm64/include/asm/psci.h b/arch/arm64/include/asm/psci.h
index e5312ea0ec1a..2454bc59c916 100644
--- a/arch/arm64/include/asm/psci.h
+++ b/arch/arm64/include/asm/psci.h
@@ -14,6 +14,7 @@
 #ifndef __ASM_PSCI_H
 #define __ASM_PSCI_H
 
-int psci_init(void);
+int psci_dt_init(void);
+int psci_acpi_init(void);
 
 #endif /* __ASM_PSCI_H */
diff --git a/arch/arm64/include/asm/smp.h b/arch/arm64/include/asm/smp.h
index 780f82c827b6..bf22650b1a78 100644
--- a/arch/arm64/include/asm/smp.h
+++ b/arch/arm64/include/asm/smp.h
@@ -39,9 +39,10 @@ extern void show_ipi_list(struct seq_file *p, int prec);
 extern void handle_IPI(int ipinr, struct pt_regs *regs);
 
 /*
- * Setup the set of possible CPUs (via set_cpu_possible)
+ * Discover the set of possible CPUs and determine their
+ * SMP operations.
  */
-extern void smp_init_cpus(void);
+extern void of_smp_init_cpus(void);
 
 /*
  * Provide a function to raise an IPI cross call on CPUs in callmap.
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index b12e15b80516..426d0763c81b 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -35,6 +35,7 @@ arm64-obj-$(CONFIG_KGDB)		+= kgdb.o
 arm64-obj-$(CONFIG_EFI)			+= efi.o efi-stub.o efi-entry.o
 arm64-obj-$(CONFIG_PCI)			+= pci.o
 arm64-obj-$(CONFIG_ARMV8_DEPRECATED)	+= armv8_deprecated.o
+arm64-obj-$(CONFIG_ACPI)		+= acpi.o
 
 obj-y					+= $(arm64-obj-y) vdso/
 obj-m					+= $(arm64-obj-m)
diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
new file mode 100644
index 000000000000..8b839558838e
--- /dev/null
+++ b/arch/arm64/kernel/acpi.c
@@ -0,0 +1,345 @@
+/*
+ *  ARM64 Specific Low-Level ACPI Boot Support
+ *
+ *  Copyright (C) 2013-2014, Linaro Ltd.
+ *	Author: Al Stone <al.stone@linaro.org>
+ *	Author: Graeme Gregory <graeme.gregory@linaro.org>
+ *	Author: Hanjun Guo <hanjun.guo@linaro.org>
+ *	Author: Tomasz Nowicki <tomasz.nowicki@linaro.org>
+ *	Author: Naresh Bhat <naresh.bhat@linaro.org>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation.
+ */
+
+#define pr_fmt(fmt) "ACPI: " fmt
+
+#include <linux/acpi.h>
+#include <linux/bootmem.h>
+#include <linux/cpumask.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/memblock.h>
+#include <linux/of_fdt.h>
+#include <linux/smp.h>
+
+#include <asm/cputype.h>
+#include <asm/cpu_ops.h>
+#include <asm/smp_plat.h>
+
+int acpi_noirq = 1;		/* skip ACPI IRQ initialization */
+int acpi_disabled = 1;
+EXPORT_SYMBOL(acpi_disabled);
+
+int acpi_pci_disabled = 1;	/* skip ACPI PCI scan and IRQ initialization */
+EXPORT_SYMBOL(acpi_pci_disabled);
+
+/* Processors with enabled flag and sane MPIDR */
+static int enabled_cpus;
+
+/* Boot CPU is valid or not in MADT */
+static bool bootcpu_valid  __initdata;
+
+static bool param_acpi_off __initdata;
+static bool param_acpi_force __initdata;
+
+static int __init parse_acpi(char *arg)
+{
+	if (!arg)
+		return -EINVAL;
+
+	/* "acpi=off" disables both ACPI table parsing and interpreter */
+	if (strcmp(arg, "off") == 0)
+		param_acpi_off = true;
+	else if (strcmp(arg, "force") == 0) /* force ACPI to be enabled */
+		param_acpi_force = true;
+	else
+		return -EINVAL;	/* Core will print when we return error */
+
+	return 0;
+}
+early_param("acpi", parse_acpi);
+
+static int __init dt_scan_depth1_nodes(unsigned long node,
+				       const char *uname, int depth,
+				       void *data)
+{
+	/*
+	 * Return 1 as soon as we encounter a node at depth 1 that is
+	 * not the /chosen node.
+	 */
+	if (depth == 1 && (strcmp(uname, "chosen") != 0))
+		return 1;
+	return 0;
+}
+
+/*
+ * __acpi_map_table() will be called before page_init(), so early_ioremap()
+ * or early_memremap() should be called here to for ACPI table mapping.
+ */
+char *__init __acpi_map_table(unsigned long phys, unsigned long size)
+{
+	if (!size)
+		return NULL;
+
+	return early_memremap(phys, size);
+}
+
+void __init __acpi_unmap_table(char *map, unsigned long size)
+{
+	if (!map || !size)
+		return;
+
+	early_memunmap(map, size);
+}
+
+/**
+ * acpi_map_gic_cpu_interface - generates a logical cpu number
+ * and map to MPIDR represented by GICC structure
+ */
+static void __init
+acpi_map_gic_cpu_interface(struct acpi_madt_generic_interrupt *processor)
+{
+	int i;
+	u64 mpidr = processor->arm_mpidr & MPIDR_HWID_BITMASK;
+	bool enabled = !!(processor->flags & ACPI_MADT_ENABLED);
+
+	if (mpidr == INVALID_HWID) {
+		pr_info("Skip MADT cpu entry with invalid MPIDR\n");
+		return;
+	}
+
+	total_cpus++;
+	if (!enabled)
+		return;
+
+	if (enabled_cpus >=  NR_CPUS) {
+		pr_warn("NR_CPUS limit of %d reached, Processor %d/0x%llx ignored.\n",
+			NR_CPUS, total_cpus, mpidr);
+		return;
+	}
+
+	/* Check if GICC structure of boot CPU is available in the MADT */
+	if (cpu_logical_map(0) == mpidr) {
+		if (bootcpu_valid) {
+			pr_err("Firmware bug, duplicate CPU MPIDR: 0x%llx in MADT\n",
+			       mpidr);
+			return;
+		}
+
+		bootcpu_valid = true;
+	}
+
+	/*
+	 * Duplicate MPIDRs are a recipe for disaster. Scan
+	 * all initialized entries and check for
+	 * duplicates. If any is found just ignore the CPU.
+	 */
+	for (i = 1; i < enabled_cpus; i++) {
+		if (cpu_logical_map(i) == mpidr) {
+			pr_err("Firmware bug, duplicate CPU MPIDR: 0x%llx in MADT\n",
+			       mpidr);
+			return;
+		}
+	}
+
+	if (!acpi_psci_present())
+		return;
+
+	cpu_ops[enabled_cpus] = cpu_get_ops("psci");
+	/* CPU 0 was already initialized */
+	if (enabled_cpus) {
+		if (!cpu_ops[enabled_cpus])
+			return;
+
+		if (cpu_ops[enabled_cpus]->cpu_init(NULL, enabled_cpus))
+			return;
+
+		/* map the logical cpu id to cpu MPIDR */
+		cpu_logical_map(enabled_cpus) = mpidr;
+	}
+
+	enabled_cpus++;
+}
+
+static int __init
+acpi_parse_gic_cpu_interface(struct acpi_subtable_header *header,
+				const unsigned long end)
+{
+	struct acpi_madt_generic_interrupt *processor;
+
+	processor = (struct acpi_madt_generic_interrupt *)header;
+
+	if (BAD_MADT_ENTRY(processor, end))
+		return -EINVAL;
+
+	acpi_table_print_madt_entry(header);
+	acpi_map_gic_cpu_interface(processor);
+	return 0;
+}
+
+/* Parse GIC cpu interface entries in MADT for SMP init */
+void __init acpi_init_cpus(void)
+{
+	int count, i;
+
+	/*
+	 * do a partial walk of MADT to determine how many CPUs
+	 * we have including disabled CPUs, and get information
+	 * we need for SMP init
+	 */
+	count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT,
+			acpi_parse_gic_cpu_interface, 0);
+
+	if (!count) {
+		pr_err("No GIC CPU interface entries present\n");
+		return;
+	} else if (count < 0) {
+		pr_err("Error parsing GIC CPU interface entry\n");
+		return;
+	}
+
+	if (!bootcpu_valid) {
+		pr_err("MADT missing boot CPU MPIDR, not enabling secondaries\n");
+		return;
+	}
+
+	for (i = 0; i < enabled_cpus; i++)
+		set_cpu_possible(i, true);
+
+	/* Make boot-up look pretty */
+	pr_info("%d CPUs enabled, %d CPUs total\n", enabled_cpus, total_cpus);
+}
+
+/*
+ * acpi_fadt_sanity_check() - Check FADT presence and carry out sanity
+ *			      checks on it
+ *
+ * Return 0 on success,  <0 on failure
+ */
+static int __init acpi_fadt_sanity_check(void)
+{
+	struct acpi_table_header *table;
+	struct acpi_table_fadt *fadt;
+	acpi_status status;
+	acpi_size tbl_size;
+	int ret = 0;
+
+	/*
+	 * FADT is required on arm64; retrieve it to check its presence
+	 * and carry out revision and ACPI HW reduced compliancy tests
+	 */
+	status = acpi_get_table_with_size(ACPI_SIG_FADT, 0, &table, &tbl_size);
+	if (ACPI_FAILURE(status)) {
+		const char *msg = acpi_format_exception(status);
+
+		pr_err("Failed to get FADT table, %s\n", msg);
+		return -ENODEV;
+	}
+
+	fadt = (struct acpi_table_fadt *)table;
+
+	/*
+	 * Revision in table header is the FADT Major revision, and there
+	 * is a minor revision of FADT which was introduced by ACPI 5.1,
+	 * we only deal with ACPI 5.1 or newer revision to get GIC and SMP
+	 * boot protocol configuration data.
+	 */
+	if (table->revision < 5 ||
+	   (table->revision == 5 && fadt->minor_revision < 1)) {
+		pr_err("Unsupported FADT revision %d.%d, should be 5.1+\n",
+		       table->revision, fadt->minor_revision);
+		ret = -EINVAL;
+		goto out;
+	}
+
+	if (!(fadt->flags & ACPI_FADT_HW_REDUCED)) {
+		pr_err("FADT not ACPI hardware reduced compliant\n");
+		ret = -EINVAL;
+	}
+
+out:
+	/*
+	 * acpi_get_table_with_size() creates FADT table mapping that
+	 * should be released after parsing and before resuming boot
+	 */
+	early_acpi_os_unmap_memory(table, tbl_size);
+	return ret;
+}
+
+/*
+ * acpi_boot_table_init() called from setup_arch(), always.
+ *	1. find RSDP and get its address, and then find XSDT
+ *	2. extract all tables and checksums them all
+ *	3. check ACPI FADT revision
+ *	4. check ACPI FADT HW reduced flag
+ *
+ * We can parse ACPI boot-time tables such as MADT after
+ * this function is called.
+ *
+ * On return ACPI is enabled if either:
+ *
+ * - ACPI tables are initialized and sanity checks passed
+ * - acpi=force was passed in the command line and ACPI was not disabled
+ *   explicitly through acpi=off command line parameter
+ *
+ * ACPI is disabled on function return otherwise
+ */
+void __init acpi_boot_table_init(void)
+{
+	/*
+	 * Enable ACPI instead of device tree unless
+	 * - ACPI has been disabled explicitly (acpi=off), or
+	 * - the device tree is not empty (it has more than just a /chosen node)
+	 *   and ACPI has not been force enabled (acpi=force)
+	 */
+	if (param_acpi_off ||
+	    (!param_acpi_force && of_scan_flat_dt(dt_scan_depth1_nodes, NULL)))
+		return;
+
+	/*
+	 * ACPI is disabled at this point. Enable it in order to parse
+	 * the ACPI tables and carry out sanity checks
+	 */
+	enable_acpi();
+
+	/*
+	 * If ACPI tables are initialized and FADT sanity checks passed,
+	 * leave ACPI enabled and carry on booting; otherwise disable ACPI
+	 * on initialization error.
+	 * If acpi=force was passed on the command line it forces ACPI
+	 * to be enabled even if its initialization failed.
+	 */
+	if (acpi_table_init() || acpi_fadt_sanity_check()) {
+		pr_err("Failed to init ACPI tables\n");
+		if (!param_acpi_force)
+			disable_acpi();
+	}
+}
+
+void __init acpi_gic_init(void)
+{
+	struct acpi_table_header *table;
+	acpi_status status;
+	acpi_size tbl_size;
+	int err;
+
+	if (acpi_disabled)
+		return;
+
+	status = acpi_get_table_with_size(ACPI_SIG_MADT, 0, &table, &tbl_size);
+	if (ACPI_FAILURE(status)) {
+		const char *msg = acpi_format_exception(status);
+
+		pr_err("Failed to get MADT table, %s\n", msg);
+		return;
+	}
+
+	err = gic_v2_acpi_init(table);
+	if (err)
+		pr_err("Failed to initialize GIC IRQ controller");
+
+	early_acpi_os_unmap_memory((char *)table, tbl_size);
+}
diff --git a/arch/arm64/kernel/cpu_ops.c b/arch/arm64/kernel/cpu_ops.c
index cce952440c64..fb8ff9ba467a 100644
--- a/arch/arm64/kernel/cpu_ops.c
+++ b/arch/arm64/kernel/cpu_ops.c
@@ -35,7 +35,7 @@ static const struct cpu_operations *supported_cpu_ops[] __initconst = {
 	NULL,
 };
 
-static const struct cpu_operations * __init cpu_get_ops(const char *name)
+const struct cpu_operations * __init cpu_get_ops(const char *name)
 {
 	const struct cpu_operations **ops = supported_cpu_ops;
 
diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c
index 6f93c24ca801..4095379dc069 100644
--- a/arch/arm64/kernel/pci.c
+++ b/arch/arm64/kernel/pci.c
@@ -10,6 +10,7 @@
  *
  */
 
+#include <linux/acpi.h>
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
@@ -46,3 +47,27 @@ int pcibios_add_device(struct pci_dev *dev)
 
 	return 0;
 }
+
+/*
+ * raw_pci_read/write - Platform-specific PCI config space access.
+ */
+int raw_pci_read(unsigned int domain, unsigned int bus,
+		  unsigned int devfn, int reg, int len, u32 *val)
+{
+	return -ENXIO;
+}
+
+int raw_pci_write(unsigned int domain, unsigned int bus,
+		unsigned int devfn, int reg, int len, u32 val)
+{
+	return -ENXIO;
+}
+
+#ifdef CONFIG_ACPI
+/* Root bridge scanning */
+struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
+{
+	/* TODO: Should be revisited when implementing PCI on ACPI */
+	return NULL;
+}
+#endif
diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c
index 9b8a70ae64a1..ea18cb53921e 100644
--- a/arch/arm64/kernel/psci.c
+++ b/arch/arm64/kernel/psci.c
@@ -15,6 +15,7 @@
 
 #define pr_fmt(fmt) "psci: " fmt
 
+#include <linux/acpi.h>
 #include <linux/init.h>
 #include <linux/of.h>
 #include <linux/smp.h>
@@ -24,6 +25,7 @@
 #include <linux/slab.h>
 #include <uapi/linux/psci.h>
 
+#include <asm/acpi.h>
 #include <asm/compiler.h>
 #include <asm/cpu_ops.h>
 #include <asm/errno.h>
@@ -273,39 +275,8 @@ static void psci_sys_poweroff(void)
 	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
 }
 
-/*
- * PSCI Function IDs for v0.2+ are well defined so use
- * standard values.
- */
-static int __init psci_0_2_init(struct device_node *np)
+static void __init psci_0_2_set_functions(void)
 {
-	int err, ver;
-
-	err = get_set_conduit_method(np);
-
-	if (err)
-		goto out_put_node;
-
-	ver = psci_get_version();
-
-	if (ver == PSCI_RET_NOT_SUPPORTED) {
-		/* PSCI v0.2 mandates implementation of PSCI_ID_VERSION. */
-		pr_err("PSCI firmware does not comply with the v0.2 spec.\n");
-		err = -EOPNOTSUPP;
-		goto out_put_node;
-	} else {
-		pr_info("PSCIv%d.%d detected in firmware.\n",
-				PSCI_VERSION_MAJOR(ver),
-				PSCI_VERSION_MINOR(ver));
-
-		if (PSCI_VERSION_MAJOR(ver) == 0 &&
-				PSCI_VERSION_MINOR(ver) < 2) {
-			err = -EINVAL;
-			pr_err("Conflicting PSCI version detected.\n");
-			goto out_put_node;
-		}
-	}
-
 	pr_info("Using standard PSCI v0.2 function IDs\n");
 	psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_0_2_FN64_CPU_SUSPEND;
 	psci_ops.cpu_suspend = psci_cpu_suspend;
@@ -329,6 +300,60 @@ static int __init psci_0_2_init(struct device_node *np)
 	arm_pm_restart = psci_sys_reset;
 
 	pm_power_off = psci_sys_poweroff;
+}
+
+/*
+ * Probe function for PSCI firmware versions >= 0.2
+ */
+static int __init psci_probe(void)
+{
+	int ver = psci_get_version();
+
+	if (ver == PSCI_RET_NOT_SUPPORTED) {
+		/*
+		 * PSCI versions >=0.2 mandates implementation of
+		 * PSCI_VERSION.
+		 */
+		pr_err("PSCI firmware does not comply with the v0.2 spec.\n");
+		return -EOPNOTSUPP;
+	} else {
+		pr_info("PSCIv%d.%d detected in firmware.\n",
+				PSCI_VERSION_MAJOR(ver),
+				PSCI_VERSION_MINOR(ver));
+
+		if (PSCI_VERSION_MAJOR(ver) == 0 &&
+				PSCI_VERSION_MINOR(ver) < 2) {
+			pr_err("Conflicting PSCI version detected.\n");
+			return -EINVAL;
+		}
+	}
+
+	psci_0_2_set_functions();
+
+	return 0;
+}
+
+/*
+ * PSCI init function for PSCI versions >=0.2
+ *
+ * Probe based on PSCI PSCI_VERSION function
+ */
+static int __init psci_0_2_init(struct device_node *np)
+{
+	int err;
+
+	err = get_set_conduit_method(np);
+
+	if (err)
+		goto out_put_node;
+	/*
+	 * Starting with v0.2, the PSCI specification introduced a call
+	 * (PSCI_VERSION) that allows probing the firmware version, so
+	 * that PSCI function IDs and version specific initialization
+	 * can be carried out according to the specific version reported
+	 * by firmware
+	 */
+	err = psci_probe();
 
 out_put_node:
 	of_node_put(np);
@@ -381,7 +406,7 @@ static const struct of_device_id psci_of_match[] __initconst = {
 	{},
 };
 
-int __init psci_init(void)
+int __init psci_dt_init(void)
 {
 	struct device_node *np;
 	const struct of_device_id *matched_np;
@@ -396,6 +421,27 @@ int __init psci_init(void)
 	return init_fn(np);
 }
 
+/*
+ * We use PSCI 0.2+ when ACPI is deployed on ARM64 and it's
+ * explicitly clarified in SBBR
+ */
+int __init psci_acpi_init(void)
+{
+	if (!acpi_psci_present()) {
+		pr_info("is not implemented in ACPI.\n");
+		return -EOPNOTSUPP;
+	}
+
+	pr_info("probing for conduit method from ACPI.\n");
+
+	if (acpi_psci_use_hvc())
+		invoke_psci_fn = __invoke_psci_fn_hvc;
+	else
+		invoke_psci_fn = __invoke_psci_fn_smc;
+
+	return psci_probe();
+}
+
 #ifdef CONFIG_SMP
 
 static int __init cpu_psci_cpu_init(struct device_node *dn, unsigned int cpu)
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index 51ef97274b52..74753132c3ac 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -17,6 +17,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <linux/acpi.h>
 #include <linux/export.h>
 #include <linux/kernel.h>
 #include <linux/stddef.h>
@@ -46,6 +47,7 @@
 #include <linux/efi.h>
 #include <linux/personality.h>
 
+#include <asm/acpi.h>
 #include <asm/fixmap.h>
 #include <asm/cpu.h>
 #include <asm/cputype.h>
@@ -395,18 +397,27 @@ void __init setup_arch(char **cmdline_p)
 	efi_init();
 	arm64_memblock_init();
 
+	/* Parse the ACPI tables for possible boot-time configuration */
+	acpi_boot_table_init();
+
 	paging_init();
 	request_standard_resources();
 
 	early_ioremap_reset();
 
-	unflatten_device_tree();
-
-	psci_init();
+	if (acpi_disabled) {
+		unflatten_device_tree();
+		psci_dt_init();
+		cpu_read_bootcpu_ops();
+#ifdef CONFIG_SMP
+		of_smp_init_cpus();
+#endif
+	} else {
+		psci_acpi_init();
+		acpi_init_cpus();
+	}
 
-	cpu_read_bootcpu_ops();
 #ifdef CONFIG_SMP
-	smp_init_cpus();
 	smp_build_mpidr_hash();
 #endif
 
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index 714411f62391..2cb008177252 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -323,7 +323,7 @@ void __init smp_prepare_boot_cpu(void)
  * cpu logical map array containing MPIDR values related to logical
  * cpus. Assumes that cpu_logical_map(0) has already been initialized.
  */
-void __init smp_init_cpus(void)
+void __init of_smp_init_cpus(void)
 {
 	struct device_node *dn = NULL;
 	unsigned int i, cpu = 1;
diff --git a/arch/arm64/kernel/time.c b/arch/arm64/kernel/time.c
index 1a7125c3099b..42f9195cf2f8 100644
--- a/arch/arm64/kernel/time.c
+++ b/arch/arm64/kernel/time.c
@@ -35,6 +35,7 @@
 #include <linux/delay.h>
 #include <linux/clocksource.h>
 #include <linux/clk-provider.h>
+#include <linux/acpi.h>
 
 #include <clocksource/arm_arch_timer.h>
 
@@ -72,6 +73,12 @@ void __init time_init(void)
 
 	tick_setup_hrtimer_broadcast();
 
+	/*
+	 * Since ACPI or FDT will only one be available in the system,
+	 * we can use acpi_generic_timer_init() here safely
+	 */
+	acpi_generic_timer_init();
+
 	arch_timer_rate = arch_timer_get_rate();
 	if (!arch_timer_rate)
 		panic("Unable to initialise architected timer.\n");
diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index 4f9a6661491b..76d25b2cfbbe 100644
--- a/arch/ia64/Kconfig
+++ b/arch/ia64/Kconfig
@@ -15,6 +15,7 @@ config IA64
 	select ARCH_MIGHT_HAVE_PC_SERIO
 	select PCI if (!IA64_HP_SIM)
 	select ACPI if (!IA64_HP_SIM)
+	select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
 	select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
 	select HAVE_UNSTABLE_SCHED_CLOCK
 	select HAVE_IDE
diff --git a/arch/ia64/kernel/acpi.c b/arch/ia64/kernel/acpi.c
index 35bf22cc71b7..b1698bc042c8 100644
--- a/arch/ia64/kernel/acpi.c
+++ b/arch/ia64/kernel/acpi.c
@@ -887,7 +887,7 @@ static int _acpi_map_lsapic(acpi_handle handle, int physid, int *pcpu)
 }
 
 /* wrapper to silence section mismatch warning */
-int __ref acpi_map_cpu(acpi_handle handle, int physid, int *pcpu)
+int __ref acpi_map_cpu(acpi_handle handle, phys_cpuid_t physid, int *pcpu)
 {
 	return _acpi_map_lsapic(handle, physid, pcpu);
 }
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 6049d587599e..226d5696e1d1 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -22,6 +22,7 @@ config X86_64
 ### Arch settings
 config X86
 	def_bool y
+	select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
 	select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
 	select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
 	select ARCH_HAS_FAST_MULTIPLIER
diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 803b684676ff..dbe76a14c3c9 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -757,7 +757,7 @@ static int _acpi_map_lsapic(acpi_handle handle, int physid, int *pcpu)
 }
 
 /* wrapper to silence section mismatch warning */
-int __ref acpi_map_cpu(acpi_handle handle, int physid, int *pcpu)
+int __ref acpi_map_cpu(acpi_handle handle, phys_cpuid_t physid, int *pcpu)
 {
 	return _acpi_map_lsapic(handle, physid, pcpu);
 }
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index e6c3ddd92665..ab2cbb51c6aa 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -5,7 +5,7 @@
 menuconfig ACPI
 	bool "ACPI (Advanced Configuration and Power Interface) Support"
 	depends on !IA64_HP_SIM
-	depends on IA64 || X86
+	depends on IA64 || X86 || (ARM64 && EXPERT)
 	depends on PCI
 	select PNP
 	default y
@@ -48,9 +48,16 @@ config ACPI_LEGACY_TABLES_LOOKUP
 config ARCH_MIGHT_HAVE_ACPI_PDC
 	bool
 
+config ACPI_GENERIC_GSI
+	bool
+
+config ACPI_SYSTEM_POWER_STATES_SUPPORT
+	bool
+
 config ACPI_SLEEP
 	bool
 	depends on SUSPEND || HIBERNATION
+	depends on ACPI_SYSTEM_POWER_STATES_SUPPORT
 	default y
 
 config ACPI_PROCFS_POWER
@@ -163,6 +170,7 @@ config ACPI_PROCESSOR
 	tristate "Processor"
 	select THERMAL
 	select CPU_IDLE
+	depends on X86 || IA64
 	default y
 	help
 	  This driver installs ACPI as the idle handler for Linux and uses
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 623b117ad1a2..8a063e276530 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -23,7 +23,7 @@ acpi-y				+= nvs.o
 
 # Power management related files
 acpi-y				+= wakeup.o
-acpi-y				+= sleep.o
+acpi-$(CONFIG_ACPI_SYSTEM_POWER_STATES_SUPPORT) += sleep.o
 acpi-y				+= device_pm.o
 acpi-$(CONFIG_ACPI_SLEEP)	+= proc.o
 
@@ -56,6 +56,7 @@ ifdef CONFIG_ACPI_VIDEO
 acpi-y				+= video_detect.o
 endif
 acpi-y				+= acpi_lpat.o
+acpi-$(CONFIG_ACPI_GENERIC_GSI) += gsi.o
 
 # These are (potentially) separate modules
 
diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index 1020b1b53a17..58f335ca2e75 100644
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -170,7 +170,7 @@ static int acpi_processor_hotadd_init(struct acpi_processor *pr)
 	acpi_status status;
 	int ret;
 
-	if (pr->phys_id == -1)
+	if (pr->phys_id == PHYS_CPUID_INVALID)
 		return -ENODEV;
 
 	status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta);
@@ -215,7 +215,8 @@ static int acpi_processor_get_info(struct acpi_device *device)
 	union acpi_object object = { 0 };
 	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
 	struct acpi_processor *pr = acpi_driver_data(device);
-	int phys_id, cpu_index, device_declaration = 0;
+	phys_cpuid_t phys_id;
+	int cpu_index, device_declaration = 0;
 	acpi_status status = AE_OK;
 	static int cpu0_initialized;
 	unsigned long long value;
@@ -263,7 +264,7 @@ static int acpi_processor_get_info(struct acpi_device *device)
 	}
 
 	phys_id = acpi_get_phys_id(pr->handle, device_declaration, pr->acpi_id);
-	if (phys_id < 0)
+	if (phys_id == PHYS_CPUID_INVALID)
 		acpi_handle_debug(pr->handle, "failed to get CPU physical ID.\n");
 	pr->phys_id = phys_id;
 
diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index 8b67bd0f6bb5..c412fdb28d34 100644
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -448,6 +448,9 @@ static int __init acpi_bus_init_irq(void)
 	case ACPI_IRQ_MODEL_IOSAPIC:
 		message = "IOSAPIC";
 		break;
+	case ACPI_IRQ_MODEL_GIC:
+		message = "GIC";
+		break;
 	case ACPI_IRQ_MODEL_PLATFORM:
 		message = "platform specific model";
 		break;
diff --git a/drivers/acpi/gsi.c b/drivers/acpi/gsi.c
new file mode 100644
index 000000000000..38208f2d0e69
--- /dev/null
+++ b/drivers/acpi/gsi.c
@@ -0,0 +1,105 @@
+/*
+ * ACPI GSI IRQ layer
+ *
+ * Copyright (C) 2015 ARM Ltd.
+ * Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/acpi.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+
+enum acpi_irq_model_id acpi_irq_model;
+
+static unsigned int acpi_gsi_get_irq_type(int trigger, int polarity)
+{
+	switch (polarity) {
+	case ACPI_ACTIVE_LOW:
+		return trigger == ACPI_EDGE_SENSITIVE ?
+		       IRQ_TYPE_EDGE_FALLING :
+		       IRQ_TYPE_LEVEL_LOW;
+	case ACPI_ACTIVE_HIGH:
+		return trigger == ACPI_EDGE_SENSITIVE ?
+		       IRQ_TYPE_EDGE_RISING :
+		       IRQ_TYPE_LEVEL_HIGH;
+	case ACPI_ACTIVE_BOTH:
+		if (trigger == ACPI_EDGE_SENSITIVE)
+			return IRQ_TYPE_EDGE_BOTH;
+	default:
+		return IRQ_TYPE_NONE;
+	}
+}
+
+/**
+ * acpi_gsi_to_irq() - Retrieve the linux irq number for a given GSI
+ * @gsi: GSI IRQ number to map
+ * @irq: pointer where linux IRQ number is stored
+ *
+ * irq location updated with irq value [>0 on success, 0 on failure]
+ *
+ * Returns: linux IRQ number on success (>0)
+ *          -EINVAL on failure
+ */
+int acpi_gsi_to_irq(u32 gsi, unsigned int *irq)
+{
+	/*
+	 * Only default domain is supported at present, always find
+	 * the mapping corresponding to default domain by passing NULL
+	 * as irq_domain parameter
+	 */
+	*irq = irq_find_mapping(NULL, gsi);
+	/*
+	 * *irq == 0 means no mapping, that should
+	 * be reported as a failure
+	 */
+	return (*irq > 0) ? *irq : -EINVAL;
+}
+EXPORT_SYMBOL_GPL(acpi_gsi_to_irq);
+
+/**
+ * acpi_register_gsi() - Map a GSI to a linux IRQ number
+ * @dev: device for which IRQ has to be mapped
+ * @gsi: GSI IRQ number
+ * @trigger: trigger type of the GSI number to be mapped
+ * @polarity: polarity of the GSI to be mapped
+ *
+ * Returns: a valid linux IRQ number on success
+ *          -EINVAL on failure
+ */
+int acpi_register_gsi(struct device *dev, u32 gsi, int trigger,
+		      int polarity)
+{
+	unsigned int irq;
+	unsigned int irq_type = acpi_gsi_get_irq_type(trigger, polarity);
+
+	/*
+	 * There is no way at present to look-up the IRQ domain on ACPI,
+	 * hence always create mapping referring to the default domain
+	 * by passing NULL as irq_domain parameter
+	 */
+	irq = irq_create_mapping(NULL, gsi);
+	if (!irq)
+		return -EINVAL;
+
+	/* Set irq type if specified and different than the current one */
+	if (irq_type != IRQ_TYPE_NONE &&
+		irq_type != irq_get_trigger_type(irq))
+		irq_set_irq_type(irq, irq_type);
+	return irq;
+}
+EXPORT_SYMBOL_GPL(acpi_register_gsi);
+
+/**
+ * acpi_unregister_gsi() - Free a GSI<->linux IRQ number mapping
+ * @gsi: GSI IRQ number
+ */
+void acpi_unregister_gsi(u32 gsi)
+{
+	int irq = irq_find_mapping(NULL, gsi);
+
+	irq_dispose_mapping(irq);
+}
+EXPORT_SYMBOL_GPL(acpi_unregister_gsi);
diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
index 56b321aa2b1c..ba4a61e964be 100644
--- a/drivers/acpi/internal.h
+++ b/drivers/acpi/internal.h
@@ -161,7 +161,11 @@ void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit);
 /*--------------------------------------------------------------------------
                                   Suspend/Resume
   -------------------------------------------------------------------------- */
+#ifdef CONFIG_ACPI_SYSTEM_POWER_STATES_SUPPORT
 extern int acpi_sleep_init(void);
+#else
+static inline int acpi_sleep_init(void) { return -ENXIO; }
+#endif
 
 #ifdef CONFIG_ACPI_SLEEP
 int acpi_sleep_proc_init(void);
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index f9eeae871593..39748bb3a543 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -336,11 +336,11 @@ acpi_map_lookup_virt(void __iomem *virt, acpi_size size)
 	return NULL;
 }
 
-#ifndef CONFIG_IA64
-#define should_use_kmap(pfn)   page_is_ram(pfn)
-#else
+#if defined(CONFIG_IA64) || defined(CONFIG_ARM64)
 /* ioremap will take care of cache attributes */
 #define should_use_kmap(pfn)   0
+#else
+#define should_use_kmap(pfn)   page_is_ram(pfn)
 #endif
 
 static void __iomem *acpi_map(acpi_physical_address pg_off, unsigned long pg_sz)
diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c
index 7962651cdbd4..b1ec78b8a645 100644
--- a/drivers/acpi/processor_core.c
+++ b/drivers/acpi/processor_core.c
@@ -32,7 +32,7 @@ static struct acpi_table_madt *get_madt_table(void)
 }
 
 static int map_lapic_id(struct acpi_subtable_header *entry,
-		 u32 acpi_id, int *apic_id)
+		 u32 acpi_id, phys_cpuid_t *apic_id)
 {
 	struct acpi_madt_local_apic *lapic =
 		container_of(entry, struct acpi_madt_local_apic, header);
@@ -48,7 +48,7 @@ static int map_lapic_id(struct acpi_subtable_header *entry,
 }
 
 static int map_x2apic_id(struct acpi_subtable_header *entry,
-			 int device_declaration, u32 acpi_id, int *apic_id)
+		int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id)
 {
 	struct acpi_madt_local_x2apic *apic =
 		container_of(entry, struct acpi_madt_local_x2apic, header);
@@ -65,7 +65,7 @@ static int map_x2apic_id(struct acpi_subtable_header *entry,
 }
 
 static int map_lsapic_id(struct acpi_subtable_header *entry,
-		int device_declaration, u32 acpi_id, int *apic_id)
+		int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id)
 {
 	struct acpi_madt_local_sapic *lsapic =
 		container_of(entry, struct acpi_madt_local_sapic, header);
@@ -83,10 +83,35 @@ static int map_lsapic_id(struct acpi_subtable_header *entry,
 	return 0;
 }
 
-static int map_madt_entry(int type, u32 acpi_id)
+/*
+ * Retrieve the ARM CPU physical identifier (MPIDR)
+ */
+static int map_gicc_mpidr(struct acpi_subtable_header *entry,
+		int device_declaration, u32 acpi_id, phys_cpuid_t *mpidr)
+{
+	struct acpi_madt_generic_interrupt *gicc =
+	    container_of(entry, struct acpi_madt_generic_interrupt, header);
+
+	if (!(gicc->flags & ACPI_MADT_ENABLED))
+		return -ENODEV;
+
+	/* device_declaration means Device object in DSDT, in the
+	 * GIC interrupt model, logical processors are required to
+	 * have a Processor Device object in the DSDT, so we should
+	 * check device_declaration here
+	 */
+	if (device_declaration && (gicc->uid == acpi_id)) {
+		*mpidr = gicc->arm_mpidr;
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static phys_cpuid_t map_madt_entry(int type, u32 acpi_id)
 {
 	unsigned long madt_end, entry;
-	int phys_id = -1;	/* CPU hardware ID */
+	phys_cpuid_t phys_id = PHYS_CPUID_INVALID;	/* CPU hardware ID */
 	struct acpi_table_madt *madt;
 
 	madt = get_madt_table();
@@ -111,18 +136,21 @@ static int map_madt_entry(int type, u32 acpi_id)
 		} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
 			if (!map_lsapic_id(header, type, acpi_id, &phys_id))
 				break;
+		} else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) {
+			if (!map_gicc_mpidr(header, type, acpi_id, &phys_id))
+				break;
 		}
 		entry += header->length;
 	}
 	return phys_id;
 }
 
-static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
+static phys_cpuid_t map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
 {
 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 	union acpi_object *obj;
 	struct acpi_subtable_header *header;
-	int phys_id = -1;
+	phys_cpuid_t phys_id = PHYS_CPUID_INVALID;
 
 	if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
 		goto exit;
@@ -143,33 +171,35 @@ static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
 		map_lsapic_id(header, type, acpi_id, &phys_id);
 	else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC)
 		map_x2apic_id(header, type, acpi_id, &phys_id);
+	else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT)
+		map_gicc_mpidr(header, type, acpi_id, &phys_id);
 
 exit:
 	kfree(buffer.pointer);
 	return phys_id;
 }
 
-int acpi_get_phys_id(acpi_handle handle, int type, u32 acpi_id)
+phys_cpuid_t acpi_get_phys_id(acpi_handle handle, int type, u32 acpi_id)
 {
-	int phys_id;
+	phys_cpuid_t phys_id;
 
 	phys_id = map_mat_entry(handle, type, acpi_id);
-	if (phys_id == -1)
+	if (phys_id == PHYS_CPUID_INVALID)
 		phys_id = map_madt_entry(type, acpi_id);
 
 	return phys_id;
 }
 
-int acpi_map_cpuid(int phys_id, u32 acpi_id)
+int acpi_map_cpuid(phys_cpuid_t phys_id, u32 acpi_id)
 {
 #ifdef CONFIG_SMP
 	int i;
 #endif
 
-	if (phys_id == -1) {
+	if (phys_id == PHYS_CPUID_INVALID) {
 		/*
 		 * On UP processor, there is no _MAT or MADT table.
-		 * So above phys_id is always set to -1.
+		 * So above phys_id is always set to PHYS_CPUID_INVALID.
 		 *
 		 * BIOS may define multiple CPU handles even for UP processor.
 		 * For example,
@@ -190,7 +220,7 @@ int acpi_map_cpuid(int phys_id, u32 acpi_id)
 		if (nr_cpu_ids <= 1 && acpi_id == 0)
 			return acpi_id;
 		else
-			return phys_id;
+			return -1;
 	}
 
 #ifdef CONFIG_SMP
@@ -208,7 +238,7 @@ int acpi_map_cpuid(int phys_id, u32 acpi_id)
 
 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
 {
-	int phys_id;
+	phys_cpuid_t phys_id;
 
 	phys_id = acpi_get_phys_id(handle, type, acpi_id);
 
diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c
index 93b81523a2fe..2e19189da0ee 100644
--- a/drivers/acpi/tables.c
+++ b/drivers/acpi/tables.c
@@ -23,6 +23,8 @@
  *
  */
 
+/* Uncomment next line to get verbose printout */
+/* #define DEBUG */
 #define pr_fmt(fmt) "ACPI: " fmt
 
 #include <linux/init.h>
@@ -61,9 +63,9 @@ void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
 		{
 			struct acpi_madt_local_apic *p =
 			    (struct acpi_madt_local_apic *)header;
-			pr_info("LAPIC (acpi_id[0x%02x] lapic_id[0x%02x] %s)\n",
-				p->processor_id, p->id,
-				(p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
+			pr_debug("LAPIC (acpi_id[0x%02x] lapic_id[0x%02x] %s)\n",
+				 p->processor_id, p->id,
+				 (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
 		}
 		break;
 
@@ -71,9 +73,9 @@ void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
 		{
 			struct acpi_madt_local_x2apic *p =
 			    (struct acpi_madt_local_x2apic *)header;
-			pr_info("X2APIC (apic_id[0x%02x] uid[0x%02x] %s)\n",
-				p->local_apic_id, p->uid,
-				(p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
+			pr_debug("X2APIC (apic_id[0x%02x] uid[0x%02x] %s)\n",
+				 p->local_apic_id, p->uid,
+				 (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
 		}
 		break;
 
@@ -81,8 +83,8 @@ void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
 		{
 			struct acpi_madt_io_apic *p =
 			    (struct acpi_madt_io_apic *)header;
-			pr_info("IOAPIC (id[0x%02x] address[0x%08x] gsi_base[%d])\n",
-				p->id, p->address, p->global_irq_base);
+			pr_debug("IOAPIC (id[0x%02x] address[0x%08x] gsi_base[%d])\n",
+				 p->id, p->address, p->global_irq_base);
 		}
 		break;
 
@@ -155,9 +157,9 @@ void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
 		{
 			struct acpi_madt_io_sapic *p =
 			    (struct acpi_madt_io_sapic *)header;
-			pr_info("IOSAPIC (id[0x%x] address[%p] gsi_base[%d])\n",
-				p->id, (void *)(unsigned long)p->address,
-				p->global_irq_base);
+			pr_debug("IOSAPIC (id[0x%x] address[%p] gsi_base[%d])\n",
+				 p->id, (void *)(unsigned long)p->address,
+				 p->global_irq_base);
 		}
 		break;
 
@@ -165,9 +167,9 @@ void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
 		{
 			struct acpi_madt_local_sapic *p =
 			    (struct acpi_madt_local_sapic *)header;
-			pr_info("LSAPIC (acpi_id[0x%02x] lsapic_id[0x%02x] lsapic_eid[0x%02x] %s)\n",
-				p->processor_id, p->id, p->eid,
-				(p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
+			pr_debug("LSAPIC (acpi_id[0x%02x] lsapic_id[0x%02x] lsapic_eid[0x%02x] %s)\n",
+				 p->processor_id, p->id, p->eid,
+				 (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
 		}
 		break;
 
@@ -183,6 +185,28 @@ void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
 		}
 		break;
 
+	case ACPI_MADT_TYPE_GENERIC_INTERRUPT:
+		{
+			struct acpi_madt_generic_interrupt *p =
+				(struct acpi_madt_generic_interrupt *)header;
+			pr_debug("GICC (acpi_id[0x%04x] address[%llx] MPIDR[0x%llx] %s)\n",
+				 p->uid, p->base_address,
+				 p->arm_mpidr,
+				 (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
+
+		}
+		break;
+
+	case ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR:
+		{
+			struct acpi_madt_generic_distributor *p =
+				(struct acpi_madt_generic_distributor *)header;
+			pr_debug("GIC Distributor (gic_id[0x%04x] address[%llx] gsi_base[%d])\n",
+				 p->gic_id, p->base_address,
+				 p->global_irq_base);
+		}
+		break;
+
 	default:
 		pr_warn("Found unsupported MADT entry (type = 0x%x)\n",
 			header->type);
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 266469691e58..0aa135ddbf80 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -22,6 +22,7 @@
 #include <linux/io.h>
 #include <linux/slab.h>
 #include <linux/sched_clock.h>
+#include <linux/acpi.h>
 
 #include <asm/arch_timer.h>
 #include <asm/virt.h>
@@ -371,8 +372,12 @@ arch_timer_detect_rate(void __iomem *cntbase, struct device_node *np)
 	if (arch_timer_rate)
 		return;
 
-	/* Try to determine the frequency from the device tree or CNTFRQ */
-	if (of_property_read_u32(np, "clock-frequency", &arch_timer_rate)) {
+	/*
+	 * Try to determine the frequency from the device tree or CNTFRQ,
+	 * if ACPI is enabled, get the frequency from CNTFRQ ONLY.
+	 */
+	if (!acpi_disabled ||
+	    of_property_read_u32(np, "clock-frequency", &arch_timer_rate)) {
 		if (cntbase)
 			arch_timer_rate = readl_relaxed(cntbase + CNTFRQ);
 		else
@@ -691,28 +696,8 @@ static void __init arch_timer_common_init(void)
 	arch_timer_arch_init();
 }
 
-static void __init arch_timer_init(struct device_node *np)
+static void __init arch_timer_init(void)
 {
-	int i;
-
-	if (arch_timers_present & ARCH_CP15_TIMER) {
-		pr_warn("arch_timer: multiple nodes in dt, skipping\n");
-		return;
-	}
-
-	arch_timers_present |= ARCH_CP15_TIMER;
-	for (i = PHYS_SECURE_PPI; i < MAX_TIMER_PPI; i++)
-		arch_timer_ppi[i] = irq_of_parse_and_map(np, i);
-	arch_timer_detect_rate(NULL, np);
-
-	/*
-	 * If we cannot rely on firmware initializing the timer registers then
-	 * we should use the physical timers instead.
-	 */
-	if (IS_ENABLED(CONFIG_ARM) &&
-	    of_property_read_bool(np, "arm,cpu-registers-not-fw-configured"))
-			arch_timer_use_virtual = false;
-
 	/*
 	 * If HYP mode is available, we know that the physical timer
 	 * has been configured to be accessible from PL1. Use it, so
@@ -731,13 +716,39 @@ static void __init arch_timer_init(struct device_node *np)
 		}
 	}
 
-	arch_timer_c3stop = !of_property_read_bool(np, "always-on");
-
 	arch_timer_register();
 	arch_timer_common_init();
 }
-CLOCKSOURCE_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_init);
-CLOCKSOURCE_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_init);
+
+static void __init arch_timer_of_init(struct device_node *np)
+{
+	int i;
+
+	if (arch_timers_present & ARCH_CP15_TIMER) {
+		pr_warn("arch_timer: multiple nodes in dt, skipping\n");
+		return;
+	}
+
+	arch_timers_present |= ARCH_CP15_TIMER;
+	for (i = PHYS_SECURE_PPI; i < MAX_TIMER_PPI; i++)
+		arch_timer_ppi[i] = irq_of_parse_and_map(np, i);
+
+	arch_timer_detect_rate(NULL, np);
+
+	arch_timer_c3stop = !of_property_read_bool(np, "always-on");
+
+	/*
+	 * If we cannot rely on firmware initializing the timer registers then
+	 * we should use the physical timers instead.
+	 */
+	if (IS_ENABLED(CONFIG_ARM) &&
+	    of_property_read_bool(np, "arm,cpu-registers-not-fw-configured"))
+			arch_timer_use_virtual = false;
+
+	arch_timer_init();
+}
+CLOCKSOURCE_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_of_init);
+CLOCKSOURCE_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_of_init);
 
 static void __init arch_timer_mem_init(struct device_node *np)
 {
@@ -804,3 +815,70 @@ static void __init arch_timer_mem_init(struct device_node *np)
 }
 CLOCKSOURCE_OF_DECLARE(armv7_arch_timer_mem, "arm,armv7-timer-mem",
 		       arch_timer_mem_init);
+
+#ifdef CONFIG_ACPI
+static int __init map_generic_timer_interrupt(u32 interrupt, u32 flags)
+{
+	int trigger, polarity;
+
+	if (!interrupt)
+		return 0;
+
+	trigger = (flags & ACPI_GTDT_INTERRUPT_MODE) ? ACPI_EDGE_SENSITIVE
+			: ACPI_LEVEL_SENSITIVE;
+
+	polarity = (flags & ACPI_GTDT_INTERRUPT_POLARITY) ? ACPI_ACTIVE_LOW
+			: ACPI_ACTIVE_HIGH;
+
+	return acpi_register_gsi(NULL, interrupt, trigger, polarity);
+}
+
+/* Initialize per-processor generic timer */
+static int __init arch_timer_acpi_init(struct acpi_table_header *table)
+{
+	struct acpi_table_gtdt *gtdt;
+
+	if (arch_timers_present & ARCH_CP15_TIMER) {
+		pr_warn("arch_timer: already initialized, skipping\n");
+		return -EINVAL;
+	}
+
+	gtdt = container_of(table, struct acpi_table_gtdt, header);
+
+	arch_timers_present |= ARCH_CP15_TIMER;
+
+	arch_timer_ppi[PHYS_SECURE_PPI] =
+		map_generic_timer_interrupt(gtdt->secure_el1_interrupt,
+		gtdt->secure_el1_flags);
+
+	arch_timer_ppi[PHYS_NONSECURE_PPI] =
+		map_generic_timer_interrupt(gtdt->non_secure_el1_interrupt,
+		gtdt->non_secure_el1_flags);
+
+	arch_timer_ppi[VIRT_PPI] =
+		map_generic_timer_interrupt(gtdt->virtual_timer_interrupt,
+		gtdt->virtual_timer_flags);
+
+	arch_timer_ppi[HYP_PPI] =
+		map_generic_timer_interrupt(gtdt->non_secure_el2_interrupt,
+		gtdt->non_secure_el2_flags);
+
+	/* Get the frequency from CNTFRQ */
+	arch_timer_detect_rate(NULL, NULL);
+
+	/* Always-on capability */
+	arch_timer_c3stop = !(gtdt->non_secure_el1_flags & ACPI_GTDT_ALWAYS_ON);
+
+	arch_timer_init();
+	return 0;
+}
+
+/* Initialize all the generic timers presented in GTDT */
+void __init acpi_generic_timer_init(void)
+{
+	if (acpi_disabled)
+		return;
+
+	acpi_table_parse(ACPI_SIG_GTDT, arch_timer_acpi_init);
+}
+#endif
diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c
index a6ce3476834e..7b315e385ba3 100644
--- a/drivers/irqchip/irq-gic.c
+++ b/drivers/irqchip/irq-gic.c
@@ -33,12 +33,14 @@
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
+#include <linux/acpi.h>
 #include <linux/irqdomain.h>
 #include <linux/interrupt.h>
 #include <linux/percpu.h>
 #include <linux/slab.h>
 #include <linux/irqchip/chained_irq.h>
 #include <linux/irqchip/arm-gic.h>
+#include <linux/irqchip/arm-gic-acpi.h>
 
 #include <asm/cputype.h>
 #include <asm/irq.h>
@@ -1107,3 +1109,105 @@ IRQCHIP_DECLARE(msm_8660_qgic, "qcom,msm-8660-qgic", gic_of_init);
 IRQCHIP_DECLARE(msm_qgic2, "qcom,msm-qgic2", gic_of_init);
 
 #endif
+
+#ifdef CONFIG_ACPI
+static phys_addr_t dist_phy_base, cpu_phy_base __initdata;
+
+static int __init
+gic_acpi_parse_madt_cpu(struct acpi_subtable_header *header,
+			const unsigned long end)
+{
+	struct acpi_madt_generic_interrupt *processor;
+	phys_addr_t gic_cpu_base;
+	static int cpu_base_assigned;
+
+	processor = (struct acpi_madt_generic_interrupt *)header;
+
+	if (BAD_MADT_ENTRY(processor, end))
+		return -EINVAL;
+
+	/*
+	 * There is no support for non-banked GICv1/2 register in ACPI spec.
+	 * All CPU interface addresses have to be the same.
+	 */
+	gic_cpu_base = processor->base_address;
+	if (cpu_base_assigned && gic_cpu_base != cpu_phy_base)
+		return -EINVAL;
+
+	cpu_phy_base = gic_cpu_base;
+	cpu_base_assigned = 1;
+	return 0;
+}
+
+static int __init
+gic_acpi_parse_madt_distributor(struct acpi_subtable_header *header,
+				const unsigned long end)
+{
+	struct acpi_madt_generic_distributor *dist;
+
+	dist = (struct acpi_madt_generic_distributor *)header;
+
+	if (BAD_MADT_ENTRY(dist, end))
+		return -EINVAL;
+
+	dist_phy_base = dist->base_address;
+	return 0;
+}
+
+int __init
+gic_v2_acpi_init(struct acpi_table_header *table)
+{
+	void __iomem *cpu_base, *dist_base;
+	int count;
+
+	/* Collect CPU base addresses */
+	count = acpi_parse_entries(ACPI_SIG_MADT,
+				   sizeof(struct acpi_table_madt),
+				   gic_acpi_parse_madt_cpu, table,
+				   ACPI_MADT_TYPE_GENERIC_INTERRUPT, 0);
+	if (count <= 0) {
+		pr_err("No valid GICC entries exist\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * Find distributor base address. We expect one distributor entry since
+	 * ACPI 5.1 spec neither support multi-GIC instances nor GIC cascade.
+	 */
+	count = acpi_parse_entries(ACPI_SIG_MADT,
+				   sizeof(struct acpi_table_madt),
+				   gic_acpi_parse_madt_distributor, table,
+				   ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR, 0);
+	if (count <= 0) {
+		pr_err("No valid GICD entries exist\n");
+		return -EINVAL;
+	} else if (count > 1) {
+		pr_err("More than one GICD entry detected\n");
+		return -EINVAL;
+	}
+
+	cpu_base = ioremap(cpu_phy_base, ACPI_GIC_CPU_IF_MEM_SIZE);
+	if (!cpu_base) {
+		pr_err("Unable to map GICC registers\n");
+		return -ENOMEM;
+	}
+
+	dist_base = ioremap(dist_phy_base, ACPI_GICV2_DIST_MEM_SIZE);
+	if (!dist_base) {
+		pr_err("Unable to map GICD registers\n");
+		iounmap(cpu_base);
+		return -ENOMEM;
+	}
+
+	/*
+	 * Initialize zero GIC instance (no multi-GIC support). Also, set GIC
+	 * as default IRQ domain to allow for GSI registration and GSI to IRQ
+	 * number translation (see acpi_register_gsi() and acpi_gsi_to_irq()).
+	 */
+	gic_init_bases(0, -1, dist_base, cpu_base, 0, NULL);
+	irq_set_default_host(gic_data[0].domain);
+
+	acpi_irq_model = ACPI_IRQ_MODEL_GIC;
+	return 0;
+}
+#endif
diff --git a/drivers/irqchip/irqchip.c b/drivers/irqchip/irqchip.c
index 0fe2f718d81c..afd1af3dfe5a 100644
--- a/drivers/irqchip/irqchip.c
+++ b/drivers/irqchip/irqchip.c
@@ -8,6 +8,7 @@
  * warranty of any kind, whether express or implied.
  */
 
+#include <linux/acpi_irq.h>
 #include <linux/init.h>
 #include <linux/of_irq.h>
 #include <linux/irqchip.h>
@@ -26,4 +27,6 @@ extern struct of_device_id __irqchip_of_table[];
 void __init irqchip_init(void)
 {
 	of_irq_init(__irqchip_of_table);
+
+	acpi_irq_init();
 }
diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig
index a270004c9605..7cd226da15fe 100644
--- a/drivers/xen/Kconfig
+++ b/drivers/xen/Kconfig
@@ -276,4 +276,8 @@ config XEN_AUTO_XLATE
 	help
 	  Support for auto-translated physmap guests.
 
+config XEN_ACPI
+	def_bool y
+	depends on X86 && ACPI
+
 endmenu
diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile
index 40edd1cbb60d..e293bc507cbc 100644
--- a/drivers/xen/Makefile
+++ b/drivers/xen/Makefile
@@ -13,7 +13,7 @@ CFLAGS_efi.o				+= -fshort-wchar
 
 dom0-$(CONFIG_PCI) += pci.o
 dom0-$(CONFIG_USB_SUPPORT) += dbgp.o
-dom0-$(CONFIG_ACPI) += acpi.o $(xen-pad-y)
+dom0-$(CONFIG_XEN_ACPI) += acpi.o $(xen-pad-y)
 xen-pad-$(CONFIG_X86) += xen-acpi-pad.o
 dom0-$(CONFIG_X86) += pcpu.o
 obj-$(CONFIG_XEN_DOM0)			+= $(dom0-y)
diff --git a/include/acpi/acpi_io.h b/include/acpi/acpi_io.h
index 444671e9c65d..dd86c5fc102d 100644
--- a/include/acpi/acpi_io.h
+++ b/include/acpi/acpi_io.h
@@ -3,11 +3,15 @@
 
 #include <linux/io.h>
 
+#include <asm/acpi.h>
+
+#ifndef acpi_os_ioremap
 static inline void __iomem *acpi_os_ioremap(acpi_physical_address phys,
 					    acpi_size size)
 {
        return ioremap_cache(phys, size);
 }
+#endif
 
 void __iomem *__init_refok
 acpi_os_map_iomem(acpi_physical_address phys, acpi_size size);
diff --git a/include/acpi/processor.h b/include/acpi/processor.h
index b95dc32a6e6b..4188a4d3b597 100644
--- a/include/acpi/processor.h
+++ b/include/acpi/processor.h
@@ -196,7 +196,7 @@ struct acpi_processor_flags {
 struct acpi_processor {
 	acpi_handle handle;
 	u32 acpi_id;
-	u32 phys_id;	/* CPU hardware ID such as APIC ID for x86 */
+	phys_cpuid_t phys_id;	/* CPU hardware ID such as APIC ID for x86 */
 	u32 id;		/* CPU logical ID allocated by OS */
 	u32 pblk;
 	int performance_platform_limit;
@@ -310,8 +310,8 @@ static inline int acpi_processor_get_bios_limit(int cpu, unsigned int *limit)
 #endif				/* CONFIG_CPU_FREQ */
 
 /* in processor_core.c */
-int acpi_get_phys_id(acpi_handle, int type, u32 acpi_id);
-int acpi_map_cpuid(int phys_id, u32 acpi_id);
+phys_cpuid_t acpi_get_phys_id(acpi_handle, int type, u32 acpi_id);
+int acpi_map_cpuid(phys_cpuid_t phys_id, u32 acpi_id);
 int acpi_get_cpuid(acpi_handle, int type, u32 acpi_id);
 
 /* in processor_pdc.c */
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index dd12127f171c..e4da5e35e29c 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -79,6 +79,7 @@ enum acpi_irq_model_id {
 	ACPI_IRQ_MODEL_IOAPIC,
 	ACPI_IRQ_MODEL_IOSAPIC,
 	ACPI_IRQ_MODEL_PLATFORM,
+	ACPI_IRQ_MODEL_GIC,
 	ACPI_IRQ_MODEL_COUNT
 };
 
@@ -152,9 +153,14 @@ void acpi_numa_x2apic_affinity_init(struct acpi_srat_x2apic_cpu_affinity *pa);
 int acpi_numa_memory_affinity_init (struct acpi_srat_mem_affinity *ma);
 void acpi_numa_arch_fixup(void);
 
+#ifndef PHYS_CPUID_INVALID
+typedef u32 phys_cpuid_t;
+#define PHYS_CPUID_INVALID (phys_cpuid_t)(-1)
+#endif
+
 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 /* Arch dependent functions for cpu hotplug support */
-int acpi_map_cpu(acpi_handle handle, int physid, int *pcpu);
+int acpi_map_cpu(acpi_handle handle, phys_cpuid_t physid, int *pcpu);
 int acpi_unmap_cpu(int cpu);
 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
 
diff --git a/include/linux/acpi_irq.h b/include/linux/acpi_irq.h
new file mode 100644
index 000000000000..f10c87265855
--- /dev/null
+++ b/include/linux/acpi_irq.h
@@ -0,0 +1,10 @@
+#ifndef _LINUX_ACPI_IRQ_H
+#define _LINUX_ACPI_IRQ_H
+
+#include <linux/irq.h>
+
+#ifndef acpi_irq_init
+static inline void acpi_irq_init(void) { }
+#endif
+
+#endif /* _LINUX_ACPI_IRQ_H */
diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
index 135509821c39..d27d0152271f 100644
--- a/include/linux/clocksource.h
+++ b/include/linux/clocksource.h
@@ -253,4 +253,10 @@ extern void clocksource_of_init(void);
 static inline void clocksource_of_init(void) {}
 #endif
 
+#ifdef CONFIG_ACPI
+void acpi_generic_timer_init(void);
+#else
+static inline void acpi_generic_timer_init(void) { }
+#endif
+
 #endif /* _LINUX_CLOCKSOURCE_H */
diff --git a/include/linux/irqchip/arm-gic-acpi.h b/include/linux/irqchip/arm-gic-acpi.h
new file mode 100644
index 000000000000..de3419ed3937
--- /dev/null
+++ b/include/linux/irqchip/arm-gic-acpi.h
@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 2014, Linaro Ltd.
+ *	Author: Tomasz Nowicki <tomasz.nowicki@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef ARM_GIC_ACPI_H_
+#define ARM_GIC_ACPI_H_
+
+#ifdef CONFIG_ACPI
+
+/*
+ * Hard code here, we can not get memory size from MADT (but FDT does),
+ * Actually no need to do that, because this size can be inferred
+ * from GIC spec.
+ */
+#define ACPI_GICV2_DIST_MEM_SIZE	(SZ_4K)
+#define ACPI_GIC_CPU_IF_MEM_SIZE	(SZ_8K)
+
+struct acpi_table_header;
+
+int gic_v2_acpi_init(struct acpi_table_header *table);
+void acpi_gic_init(void);
+#else
+static inline void acpi_gic_init(void) { }
+#endif
+
+#endif /* ARM_GIC_ACPI_H_ */