MIPS: generic: Introduce generic DT-based board support

Introduce a "generic" platform, which aims to be board-agnostic by
making use of device trees passed by the boot protocol defined in the
MIPS UHI (Universal Hosting Interface) specification. Provision is made
for supporting boards which use a legacy boot protocol that can't be
changed, but adding support for such boards or any others is left to
followon patches.

Right now the built kernels expect to be loaded to 0x80100000, ie. in
kseg0. This is fine for the vast majority of MIPS platforms, but
nevertheless it would be good to remove this limitation in the future by
mapping the kernel via the TLB such that it can be loaded anywhere & map
itself appropriately.

Configuration is handled by dynamically generating configs using
scripts/kconfig/merge_config.sh, somewhat similar to the way powerpc
makes use of it. This allows for variations upon the configuration, eg.
differing architecture revisions or subsets of driver support for
differing boards, to be handled without having a large number of
defconfig files.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14353/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

10 files changed, 122 insertions, 0 deletions

diff --git a/arch/mips/configs/generic/32r1.config b/arch/mips/configs/generic/32r1.config
new file mode 100644
index 000000000000..a11cd8715519
--- /dev/null
+++ b/arch/mips/configs/generic/32r1.config
@@ -0,0 +1,2 @@
+CONFIG_CPU_MIPS32_R1=y
+CONFIG_HIGHMEM=y
diff --git a/arch/mips/configs/generic/32r2.config b/arch/mips/configs/generic/32r2.config
new file mode 100644
index 000000000000..9570672d4f9f
--- /dev/null
+++ b/arch/mips/configs/generic/32r2.config
@@ -0,0 +1,3 @@
+CONFIG_CPU_MIPS32_R2=y
+CONFIG_MIPS_O32_FP64_SUPPORT=y
+CONFIG_HIGHMEM=y
diff --git a/arch/mips/configs/generic/32r6.config b/arch/mips/configs/generic/32r6.config
new file mode 100644
index 000000000000..ca606e71f4d0
--- /dev/null
+++ b/arch/mips/configs/generic/32r6.config
@@ -0,0 +1,2 @@
+CONFIG_CPU_MIPS32_R6=y
+CONFIG_HIGHMEM=y
diff --git a/arch/mips/configs/generic/64r1.config b/arch/mips/configs/generic/64r1.config
new file mode 100644
index 000000000000..7c1ea7e7bae3
--- /dev/null
+++ b/arch/mips/configs/generic/64r1.config
@@ -0,0 +1,4 @@
+CONFIG_CPU_MIPS64_R1=y
+CONFIG_64BIT=y
+CONFIG_MIPS32_O32=y
+CONFIG_MIPS32_N32=y
diff --git a/arch/mips/configs/generic/64r2.config b/arch/mips/configs/generic/64r2.config
new file mode 100644
index 000000000000..b4d31ae8bfec
--- /dev/null
+++ b/arch/mips/configs/generic/64r2.config
@@ -0,0 +1,5 @@
+CONFIG_CPU_MIPS64_R2=y
+CONFIG_MIPS_O32_FP64_SUPPORT=y
+CONFIG_64BIT=y
+CONFIG_MIPS32_O32=y
+CONFIG_MIPS32_N32=y
diff --git a/arch/mips/configs/generic/64r6.config b/arch/mips/configs/generic/64r6.config
new file mode 100644
index 000000000000..7cac0339c4d5
--- /dev/null
+++ b/arch/mips/configs/generic/64r6.config
@@ -0,0 +1,4 @@
+CONFIG_CPU_MIPS64_R6=y
+CONFIG_64BIT=y
+CONFIG_MIPS32_O32=y
+CONFIG_MIPS32_N32=y
diff --git a/arch/mips/configs/generic/eb.config b/arch/mips/configs/generic/eb.config
new file mode 100644
index 000000000000..c5cdc99a6530
--- /dev/null
+++ b/arch/mips/configs/generic/eb.config
@@ -0,0 +1 @@
+CONFIG_CPU_BIG_ENDIAN=y
diff --git a/arch/mips/configs/generic/el.config b/arch/mips/configs/generic/el.config
new file mode 100644
index 000000000000..ee43fdb3b8f4
--- /dev/null
+++ b/arch/mips/configs/generic/el.config
@@ -0,0 +1 @@
+CONFIG_CPU_LITTLE_ENDIAN=y
diff --git a/arch/mips/configs/generic/micro32r2.config b/arch/mips/configs/generic/micro32r2.config
new file mode 100644
index 000000000000..b701fe7aaa68
--- /dev/null
+++ b/arch/mips/configs/generic/micro32r2.config
@@ -0,0 +1,4 @@
+CONFIG_CPU_MIPS32_R2=y
+CONFIG_CPU_MICROMIPS=y
+CONFIG_MIPS_O32_FP64_SUPPORT=y
+CONFIG_HIGHMEM=y
diff --git a/arch/mips/configs/generic_defconfig b/arch/mips/configs/generic_defconfig
new file mode 100644
index 000000000000..c95d94c7838b
--- /dev/null
+++ b/arch/mips/configs/generic_defconfig
@@ -0,0 +1,96 @@
+CONFIG_MIPS_GENERIC=y
+CONFIG_CPU_LITTLE_ENDIAN=y
+CONFIG_MIPS_CPS=y
+CONFIG_CPU_HAS_MSA=y
+CONFIG_HIGHMEM=y
+CONFIG_NR_CPUS=2
+CONFIG_MIPS_O32_FP64_SUPPORT=y
+CONFIG_SYSVIPC=y
+CONFIG_NO_HZ_IDLE=y
+CONFIG_IKCONFIG=y
+CONFIG_IKCONFIG_PROC=y
+CONFIG_MEMCG=y
+CONFIG_MEMCG_SWAP=y
+CONFIG_BLK_CGROUP=y
+CONFIG_CFS_BANDWIDTH=y
+CONFIG_RT_GROUP_SCHED=y
+CONFIG_CGROUP_PIDS=y
+CONFIG_CGROUP_FREEZER=y
+CONFIG_CPUSETS=y
+CONFIG_CGROUP_DEVICE=y
+CONFIG_CGROUP_CPUACCT=y
+CONFIG_NAMESPACES=y
+CONFIG_USER_NS=y
+CONFIG_SCHED_AUTOGROUP=y
+CONFIG_BLK_DEV_INITRD=y
+CONFIG_BPF_SYSCALL=y
+CONFIG_USERFAULTFD=y
+CONFIG_EMBEDDED=y
+# CONFIG_SLUB_DEBUG is not set
+# CONFIG_COMPAT_BRK is not set
+CONFIG_CC_STACKPROTECTOR_REGULAR=y
+CONFIG_MODULES=y
+CONFIG_MODULE_UNLOAD=y
+CONFIG_TRIM_UNUSED_KSYMS=y
+CONFIG_NET=y
+CONFIG_PACKET=y
+CONFIG_UNIX=y
+CONFIG_INET=y
+CONFIG_NETFILTER=y
+# CONFIG_WIRELESS is not set
+CONFIG_DEVTMPFS=y
+CONFIG_DEVTMPFS_MOUNT=y
+CONFIG_SCSI=y
+# CONFIG_INPUT_MOUSEDEV is not set
+# CONFIG_INPUT_KEYBOARD is not set
+# CONFIG_INPUT_MOUSE is not set
+# CONFIG_SERIO is not set
+CONFIG_HW_RANDOM=y
+# CONFIG_HWMON is not set
+CONFIG_MFD_SYSCON=y
+CONFIG_HID_A4TECH=y
+CONFIG_HID_APPLE=y
+CONFIG_HID_BELKIN=y
+CONFIG_HID_CHERRY=y
+CONFIG_HID_CHICONY=y
+CONFIG_HID_CYPRESS=y
+CONFIG_HID_EZKEY=y
+CONFIG_HID_KENSINGTON=y
+CONFIG_HID_LOGITECH=y
+CONFIG_HID_MICROSOFT=y
+CONFIG_HID_MONTEREY=y
+# CONFIG_USB_SUPPORT is not set
+# CONFIG_MIPS_PLATFORM_DEVICES is not set
+# CONFIG_IOMMU_SUPPORT is not set
+CONFIG_EXT4_FS=y
+CONFIG_EXT4_FS_POSIX_ACL=y
+CONFIG_EXT4_FS_SECURITY=y
+CONFIG_EXT4_ENCRYPTION=y
+CONFIG_FANOTIFY=y
+CONFIG_FUSE_FS=y
+CONFIG_CUSE=y
+CONFIG_OVERLAY_FS=y
+CONFIG_MSDOS_FS=y
+CONFIG_VFAT_FS=y
+CONFIG_TMPFS=y
+CONFIG_TMPFS_POSIX_ACL=y
+# CONFIG_MISC_FILESYSTEMS is not set
+CONFIG_NFS_FS=y
+CONFIG_NFS_V3_ACL=y
+CONFIG_NFS_V4=y
+CONFIG_NFS_V4_1=y
+CONFIG_NFS_V4_2=y
+CONFIG_PRINTK_TIME=y
+CONFIG_DEBUG_INFO=y
+CONFIG_DEBUG_INFO_REDUCED=y
+CONFIG_DEBUG_FS=y
+# CONFIG_SCHED_DEBUG is not set
+# CONFIG_FTRACE is not set
+CONFIG_CMDLINE_BOOL=y
+CONFIG_CMDLINE="earlycon"
+# CONFIG_XZ_DEC_X86 is not set
+# CONFIG_XZ_DEC_POWERPC is not set
+# CONFIG_XZ_DEC_IA64 is not set
+# CONFIG_XZ_DEC_ARM is not set
+# CONFIG_XZ_DEC_ARMTHUMB is not set
+# CONFIG_XZ_DEC_SPARC is not set