diff options
| -rw-r--r-- | MAINTAINERS | 2 | ||||
| -rw-r--r-- | drivers/firmware/Kconfig | 19 | ||||
| -rw-r--r-- | drivers/firmware/Makefile | 1 | ||||
| -rw-r--r-- | drivers/firmware/arm_scpi.c | 711 | ||||
| -rw-r--r-- | include/linux/scpi_protocol.h | 61 |
5 files changed, 794 insertions, 0 deletions
diff --git a/MAINTAINERS b/MAINTAINERS index be7d5c14729b..9598821d6a37 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -9154,6 +9154,8 @@ M: Sudeep Holla <sudeep.holla@arm.com> L: linux-arm-kernel@lists.infradead.org S: Maintained F: Documentation/devicetree/bindings/arm/arm,scpi.txt +F: drivers/firmware/arm_scpi.c +F: include/linux/scpi_protocol.h SCSI CDROM DRIVER M: Jens Axboe <axboe@kernel.dk> diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig index d8de6a8dd4de..800b7439606e 100644 --- a/drivers/firmware/Kconfig +++ b/drivers/firmware/Kconfig @@ -8,6 +8,25 @@ menu "Firmware Drivers" config ARM_PSCI_FW bool +config ARM_SCPI_PROTOCOL + tristate "ARM System Control and Power Interface (SCPI) Message Protocol" + depends on ARM_MHU + help + System Control and Power Interface (SCPI) Message Protocol is + defined for the purpose of communication between the Application + Cores(AP) and the System Control Processor(SCP). The MHU peripheral + provides a mechanism for inter-processor communication between SCP + and AP. + + SCP controls most of the power managament on the Application + Processors. It offers control and management of: the core/cluster + power states, various power domain DVFS including the core/cluster, + certain system clocks configuration, thermal sensors and many + others. + + This protocol library provides interface for all the client drivers + making use of the features offered by the SCP. + config EDD tristate "BIOS Enhanced Disk Drive calls determine boot disk" depends on X86 diff --git a/drivers/firmware/Makefile b/drivers/firmware/Makefile index 000830fc6707..e4c3a3fa1580 100644 --- a/drivers/firmware/Makefile +++ b/drivers/firmware/Makefile @@ -2,6 +2,7 @@ # Makefile for the linux kernel. # obj-$(CONFIG_ARM_PSCI_FW) += psci.o +obj-$(CONFIG_ARM_SCPI_PROTOCOL) += arm_scpi.o obj-$(CONFIG_DMI) += dmi_scan.o obj-$(CONFIG_DMI_SYSFS) += dmi-sysfs.o obj-$(CONFIG_EDD) += edd.o diff --git a/drivers/firmware/arm_scpi.c b/drivers/firmware/arm_scpi.c new file mode 100644 index 000000000000..cb75c750ca54 --- /dev/null +++ b/drivers/firmware/arm_scpi.c @@ -0,0 +1,711 @@ +/* + * System Control and Power Interface (SCPI) Message Protocol driver + * + * SCPI Message Protocol is used between the System Control Processor(SCP) + * and the Application Processors(AP). The Message Handling Unit(MHU) + * provides a mechanism for inter-processor communication between SCP's + * Cortex M3 and AP. + * + * SCP offers control and management of the core/cluster power states, + * various power domain DVFS including the core/cluster, certain system + * clocks configuration, thermal sensors and many others. + * + * Copyright (C) 2015 ARM Ltd. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along + * with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/bitmap.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/export.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/mailbox_client.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/of_platform.h> +#include <linux/printk.h> +#include <linux/scpi_protocol.h> +#include <linux/slab.h> +#include <linux/sort.h> +#include <linux/spinlock.h> + +#define CMD_ID_SHIFT 0 +#define CMD_ID_MASK 0x7f +#define CMD_TOKEN_ID_SHIFT 8 +#define CMD_TOKEN_ID_MASK 0xff +#define CMD_DATA_SIZE_SHIFT 16 +#define CMD_DATA_SIZE_MASK 0x1ff +#define PACK_SCPI_CMD(cmd_id, tx_sz) \ + ((((cmd_id) & CMD_ID_MASK) << CMD_ID_SHIFT) | \ + (((tx_sz) & CMD_DATA_SIZE_MASK) << CMD_DATA_SIZE_SHIFT)) +#define ADD_SCPI_TOKEN(cmd, token) \ + ((cmd) |= (((token) & CMD_TOKEN_ID_MASK) << CMD_TOKEN_ID_SHIFT)) + +#define CMD_SIZE(cmd) (((cmd) >> CMD_DATA_SIZE_SHIFT) & CMD_DATA_SIZE_MASK) +#define CMD_UNIQ_MASK (CMD_TOKEN_ID_MASK << CMD_TOKEN_ID_SHIFT | CMD_ID_MASK) +#define CMD_XTRACT_UNIQ(cmd) ((cmd) & CMD_UNIQ_MASK) + +#define SCPI_SLOT 0 + +#define MAX_DVFS_DOMAINS 8 +#define MAX_DVFS_OPPS 8 +#define DVFS_LATENCY(hdr) (le32_to_cpu(hdr) >> 16) +#define DVFS_OPP_COUNT(hdr) ((le32_to_cpu(hdr) >> 8) & 0xff) + +#define PROTOCOL_REV_MINOR_BITS 16 +#define PROTOCOL_REV_MINOR_MASK ((1U << PROTOCOL_REV_MINOR_BITS) - 1) +#define PROTOCOL_REV_MAJOR(x) ((x) >> PROTOCOL_REV_MINOR_BITS) +#define PROTOCOL_REV_MINOR(x) ((x) & PROTOCOL_REV_MINOR_MASK) + +#define FW_REV_MAJOR_BITS 24 +#define FW_REV_MINOR_BITS 16 +#define FW_REV_PATCH_MASK ((1U << FW_REV_MINOR_BITS) - 1) +#define FW_REV_MINOR_MASK ((1U << FW_REV_MAJOR_BITS) - 1) +#define FW_REV_MAJOR(x) ((x) >> FW_REV_MAJOR_BITS) +#define FW_REV_MINOR(x) (((x) & FW_REV_MINOR_MASK) >> FW_REV_MINOR_BITS) +#define FW_REV_PATCH(x) ((x) & FW_REV_PATCH_MASK) + +#define MAX_RX_TIMEOUT (msecs_to_jiffies(20)) + +enum scpi_error_codes { + SCPI_SUCCESS = 0, /* Success */ + SCPI_ERR_PARAM = 1, /* Invalid parameter(s) */ + SCPI_ERR_ALIGN = 2, /* Invalid alignment */ + SCPI_ERR_SIZE = 3, /* Invalid size */ + SCPI_ERR_HANDLER = 4, /* Invalid handler/callback */ + SCPI_ERR_ACCESS = 5, /* Invalid access/permission denied */ + SCPI_ERR_RANGE = 6, /* Value out of range */ + SCPI_ERR_TIMEOUT = 7, /* Timeout has occurred */ + SCPI_ERR_NOMEM = 8, /* Invalid memory area or pointer */ + SCPI_ERR_PWRSTATE = 9, /* Invalid power state */ + SCPI_ERR_SUPPORT = 10, /* Not supported or disabled */ + SCPI_ERR_DEVICE = 11, /* Device error */ + SCPI_ERR_BUSY = 12, /* Device busy */ + SCPI_ERR_MAX +}; + +enum scpi_std_cmd { + SCPI_CMD_INVALID = 0x00, + SCPI_CMD_SCPI_READY = 0x01, + SCPI_CMD_SCPI_CAPABILITIES = 0x02, + SCPI_CMD_SET_CSS_PWR_STATE = 0x03, + SCPI_CMD_GET_CSS_PWR_STATE = 0x04, + SCPI_CMD_SET_SYS_PWR_STATE = 0x05, + SCPI_CMD_SET_CPU_TIMER = 0x06, + SCPI_CMD_CANCEL_CPU_TIMER = 0x07, + SCPI_CMD_DVFS_CAPABILITIES = 0x08, + SCPI_CMD_GET_DVFS_INFO = 0x09, + SCPI_CMD_SET_DVFS = 0x0a, + SCPI_CMD_GET_DVFS = 0x0b, + SCPI_CMD_GET_DVFS_STAT = 0x0c, + SCPI_CMD_CLOCK_CAPABILITIES = 0x0d, + SCPI_CMD_GET_CLOCK_INFO = 0x0e, + SCPI_CMD_SET_CLOCK_VALUE = 0x0f, + SCPI_CMD_GET_CLOCK_VALUE = 0x10, + SCPI_CMD_PSU_CAPABILITIES = 0x11, + SCPI_CMD_GET_PSU_INFO = 0x12, + SCPI_CMD_SET_PSU = 0x13, + SCPI_CMD_GET_PSU = 0x14, + SCPI_CMD_SENSOR_CAPABILITIES = 0x15, + SCPI_CMD_SENSOR_INFO = 0x16, + SCPI_CMD_SENSOR_VALUE = 0x17, + SCPI_CMD_SENSOR_CFG_PERIODIC = 0x18, + SCPI_CMD_SENSOR_CFG_BOUNDS = 0x19, + SCPI_CMD_SENSOR_ASYNC_VALUE = 0x1a, + SCPI_CMD_SET_DEVICE_PWR_STATE = 0x1b, + SCPI_CMD_GET_DEVICE_PWR_STATE = 0x1c, + SCPI_CMD_COUNT +}; + +struct scpi_xfer { + u32 slot; /* has to be first element */ + u32 cmd; + u32 status; + const void *tx_buf; + void *rx_buf; + unsigned int tx_len; + unsigned int rx_len; + struct list_head node; + struct completion done; +}; + +struct scpi_chan { + struct mbox_client cl; + struct mbox_chan *chan; + void __iomem *tx_payload; + void __iomem *rx_payload; + struct list_head rx_pending; + struct list_head xfers_list; + struct scpi_xfer *xfers; + spinlock_t rx_lock; /* locking for the rx pending list */ + struct mutex xfers_lock; + u8 token; +}; + +struct scpi_drvinfo { + u32 protocol_version; + u32 firmware_version; + int num_chans; + atomic_t next_chan; + struct scpi_ops *scpi_ops; + struct scpi_chan *channels; + struct scpi_dvfs_info *dvfs[MAX_DVFS_DOMAINS]; +}; + +/* + * The SCP firmware only executes in little-endian mode, so any buffers + * shared through SCPI should have their contents converted to little-endian + */ +struct scpi_shared_mem { + __le32 command; + __le32 status; + u8 payload[0]; +} __packed; + +struct scp_capabilities { + __le32 protocol_version; + __le32 event_version; + __le32 platform_version; + __le32 commands[4]; +} __packed; + +struct clk_get_info { + __le16 id; + __le16 flags; + __le32 min_rate; + __le32 max_rate; + u8 name[20]; +} __packed; + +struct clk_get_value { + __le32 rate; +} __packed; + +struct clk_set_value { + __le16 id; + __le16 reserved; + __le32 rate; +} __packed; + +struct dvfs_info { + __le32 header; + struct { + __le32 freq; + __le32 m_volt; + } opps[MAX_DVFS_OPPS]; +} __packed; + +struct dvfs_get { + u8 index; +} __packed; + +struct dvfs_set { + u8 domain; + u8 index; +} __packed; + +static struct scpi_drvinfo *scpi_info; + +static int scpi_linux_errmap[SCPI_ERR_MAX] = { + /* better than switch case as long as return value is continuous */ + 0, /* SCPI_SUCCESS */ + -EINVAL, /* SCPI_ERR_PARAM */ + -ENOEXEC, /* SCPI_ERR_ALIGN */ + -EMSGSIZE, /* SCPI_ERR_SIZE */ + -EINVAL, /* SCPI_ERR_HANDLER */ + -EACCES, /* SCPI_ERR_ACCESS */ + -ERANGE, /* SCPI_ERR_RANGE */ + -ETIMEDOUT, /* SCPI_ERR_TIMEOUT */ + -ENOMEM, /* SCPI_ERR_NOMEM */ + -EINVAL, /* SCPI_ERR_PWRSTATE */ + -EOPNOTSUPP, /* SCPI_ERR_SUPPORT */ + -EIO, /* SCPI_ERR_DEVICE */ + -EBUSY, /* SCPI_ERR_BUSY */ +}; + +static inline int scpi_to_linux_errno(int errno) +{ + if (errno >= SCPI_SUCCESS && errno < SCPI_ERR_MAX) + return scpi_linux_errmap[errno]; + return -EIO; +} + +static void scpi_process_cmd(struct scpi_chan *ch, u32 cmd) +{ + unsigned long flags; + struct scpi_xfer *t, *match = NULL; + + spin_lock_irqsave(&ch->rx_lock, flags); + if (list_empty(&ch->rx_pending)) { + spin_unlock_irqrestore(&ch->rx_lock, flags); + return; + } + + list_for_each_entry(t, &ch->rx_pending, node) + if (CMD_XTRACT_UNIQ(t->cmd) == CMD_XTRACT_UNIQ(cmd)) { + list_del(&t->node); + match = t; + break; + } + /* check if wait_for_completion is in progress or timed-out */ + if (match && !completion_done(&match->done)) { + struct scpi_shared_mem *mem = ch->rx_payload; + unsigned int len = min(match->rx_len, CMD_SIZE(cmd)); + + match->status = le32_to_cpu(mem->status); + memcpy_fromio(match->rx_buf, mem->payload, len); + if (match->rx_len > len) + memset(match->rx_buf + len, 0, match->rx_len - len); + complete(&match->done); + } + spin_unlock_irqrestore(&ch->rx_lock, flags); +} + +static void scpi_handle_remote_msg(struct mbox_client *c, void *msg) +{ + struct scpi_chan *ch = container_of(c, struct scpi_chan, cl); + struct scpi_shared_mem *mem = ch->rx_payload; + u32 cmd = le32_to_cpu(mem->command); + + scpi_process_cmd(ch, cmd); +} + +static void scpi_tx_prepare(struct mbox_client *c, void *msg) +{ + unsigned long flags; + struct scpi_xfer *t = msg; + struct scpi_chan *ch = container_of(c, struct scpi_chan, cl); + struct scpi_shared_mem *mem = (struct scpi_shared_mem *)ch->tx_payload; + + if (t->tx_buf) + memcpy_toio(mem->payload, t->tx_buf, t->tx_len); + if (t->rx_buf) { + if (!(++ch->token)) + ++ch->token; + ADD_SCPI_TOKEN(t->cmd, ch->token); + spin_lock_irqsave(&ch->rx_lock, flags); + list_add_tail(&t->node, &ch->rx_pending); + spin_unlock_irqrestore(&ch->rx_lock, flags); + } + mem->command = cpu_to_le32(t->cmd); +} + +static struct scpi_xfer *get_scpi_xfer(struct scpi_chan *ch) +{ + struct scpi_xfer *t; + + mutex_lock(&ch->xfers_lock); + if (list_empty(&ch->xfers_list)) { + mutex_unlock(&ch->xfers_lock); + return NULL; + } + t = list_first_entry(&ch->xfers_list, struct scpi_xfer, node); + list_del(&t->node); + mutex_unlock(&ch->xfers_lock); + return t; +} + +static void put_scpi_xfer(struct scpi_xfer *t, struct scpi_chan *ch) +{ + mutex_lock(&ch->xfers_lock); + list_add_tail(&t->node, &ch->xfers_list); + mutex_unlock(&ch->xfers_lock); +} + +static int scpi_send_message(u8 cmd, void *tx_buf, unsigned int tx_len, + void *rx_buf, unsigned int rx_len) +{ + int ret; + u8 chan; + struct scpi_xfer *msg; + struct scpi_chan *scpi_chan; + + chan = atomic_inc_return(&scpi_info->next_chan) % scpi_info->num_chans; + scpi_chan = scpi_info->channels + chan; + + msg = get_scpi_xfer(scpi_chan); + if (!msg) + return -ENOMEM; + + msg->slot = BIT(SCPI_SLOT); + msg->cmd = PACK_SCPI_CMD(cmd, tx_len); + msg->tx_buf = tx_buf; + msg->tx_len = tx_len; + msg->rx_buf = rx_buf; + msg->rx_len = rx_len; + init_completion(&msg->done); + + ret = mbox_send_message(scpi_chan->chan, msg); + if (ret < 0 || !rx_buf) + goto out; + + if (!wait_for_completion_timeout(&msg->done, MAX_RX_TIMEOUT)) + ret = -ETIMEDOUT; + else + /* first status word */ + ret = le32_to_cpu(msg->status); +out: + if (ret < 0 && rx_buf) /* remove entry from the list if timed-out */ + scpi_process_cmd(scpi_chan, msg->cmd); + + put_scpi_xfer(msg, scpi_chan); + /* SCPI error codes > 0, translate them to Linux scale*/ + return ret > 0 ? scpi_to_linux_errno(ret) : ret; +} + +static u32 scpi_get_version(void) +{ + return scpi_info->protocol_version; +} + +static int +scpi_clk_get_range(u16 clk_id, unsigned long *min, unsigned long *max) +{ + int ret; + struct clk_get_info clk; + __le16 le_clk_id = cpu_to_le16(clk_id); + + ret = scpi_send_message(SCPI_CMD_GET_CLOCK_INFO, &le_clk_id, + sizeof(le_clk_id), &clk, sizeof(clk)); + if (!ret) { + *min = le32_to_cpu(clk.min_rate); + *max = le32_to_cpu(clk.max_rate); + } + return ret; +} + +static unsigned long scpi_clk_get_val(u16 clk_id) +{ + int ret; + struct clk_get_value clk; + __le16 le_clk_id = cpu_to_le16(clk_id); + + ret = scpi_send_message(SCPI_CMD_GET_CLOCK_VALUE, &le_clk_id, + sizeof(le_clk_id), &clk, sizeof(clk)); + return ret ? ret : le32_to_cpu(clk.rate); +} + +static int scpi_clk_set_val(u16 clk_id, unsigned long rate) +{ + int stat; + struct clk_set_value clk = { + .id = cpu_to_le16(clk_id), + .rate = cpu_to_le32(rate) + }; + + return scpi_send_message(SCPI_CMD_SET_CLOCK_VALUE, &clk, sizeof(clk), + &stat, sizeof(stat)); +} + +static int scpi_dvfs_get_idx(u8 domain) +{ + int ret; + struct dvfs_get dvfs; + + ret = scpi_send_message(SCPI_CMD_GET_DVFS, &domain, sizeof(domain), + &dvfs, sizeof(dvfs)); + return ret ? ret : dvfs.index; +} + +static int scpi_dvfs_set_idx(u8 domain, u8 index) +{ + int stat; + struct dvfs_set dvfs = {domain, index}; + + return scpi_send_message(SCPI_CMD_SET_DVFS, &dvfs, sizeof(dvfs), + &stat, sizeof(stat)); +} + +static int opp_cmp_func(const void *opp1, const void *opp2) +{ + const struct scpi_opp *t1 = opp1, *t2 = opp2; + + return t1->freq - t2->freq; +} + +static struct scpi_dvfs_info *scpi_dvfs_get_info(u8 domain) +{ + struct scpi_dvfs_info *info; + struct scpi_opp *opp; + struct dvfs_info buf; + int ret, i; + + if (domain >= MAX_DVFS_DOMAINS) + return ERR_PTR(-EINVAL); + + if (scpi_info->dvfs[domain]) /* data already populated */ + return scpi_info->dvfs[domain]; + + ret = scpi_send_message(SCPI_CMD_GET_DVFS_INFO, &domain, sizeof(domain), + &buf, sizeof(buf)); + + if (ret) + return ERR_PTR(ret); + + info = kmalloc(sizeof(*info), GFP_KERNEL); + if (!info) + return ERR_PTR(-ENOMEM); + + info->count = DVFS_OPP_COUNT(buf.header); + info->latency = DVFS_LATENCY(buf.header) * 1000; /* uS to nS */ + + info->opps = kcalloc(info->count, sizeof(*opp), GFP_KERNEL); + if (!info->opps) { + kfree(info); + return ERR_PTR(-ENOMEM); + } + + for (i = 0, opp = info->opps; i < info->count; i++, opp++) { + opp->freq = le32_to_cpu(buf.opps[i].freq); + opp->m_volt = le32_to_cpu(buf.opps[i].m_volt); + } + + sort(info->opps, info->count, sizeof(*opp), opp_cmp_func, NULL); + + scpi_info->dvfs[domain] = info; + return info; +} + +static struct scpi_ops scpi_ops = { + .get_version = scpi_get_version, + .clk_get_range = scpi_clk_get_range, + .clk_get_val = scpi_clk_get_val, + .clk_set_val = scpi_clk_set_val, + .dvfs_get_idx = scpi_dvfs_get_idx, + .dvfs_set_idx = scpi_dvfs_set_idx, + .dvfs_get_info = scpi_dvfs_get_info, +}; + +struct scpi_ops *get_scpi_ops(void) +{ + return scpi_info ? scpi_info->scpi_ops : NULL; +} +EXPORT_SYMBOL_GPL(get_scpi_ops); + +static int scpi_init_versions(struct scpi_drvinfo *info) +{ + int ret; + struct scp_capabilities caps; + + ret = scpi_send_message(SCPI_CMD_SCPI_CAPABILITIES, NULL, 0, + &caps, sizeof(caps)); + if (!ret) { + info->protocol_version = le32_to_cpu(caps.protocol_version); + info->firmware_version = le32_to_cpu(caps.platform_version); + } + return ret; +} + +static ssize_t protocol_version_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct scpi_drvinfo *scpi_info = dev_get_drvdata(dev); + + return sprintf(buf, "%d.%d\n", + PROTOCOL_REV_MAJOR(scpi_info->protocol_version), + PROTOCOL_REV_MINOR(scpi_info->protocol_version)); +} +static DEVICE_ATTR_RO(protocol_version); + +static ssize_t firmware_version_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct scpi_drvinfo *scpi_info = dev_get_drvdata(dev); + + return sprintf(buf, "%d.%d.%d\n", + FW_REV_MAJOR(scpi_info->firmware_version), + FW_REV_MINOR(scpi_info->firmware_version), + FW_REV_PATCH(scpi_info->firmware_version)); +} +static DEVICE_ATTR_RO(firmware_version); + +static struct attribute *versions_attrs[] = { + &dev_attr_firmware_version.attr, + &dev_attr_protocol_version.attr, + NULL, +}; +ATTRIBUTE_GROUPS(versions); + +static void +scpi_free_channels(struct device *dev, struct scpi_chan *pchan, int count) +{ + int i; + + for (i = 0; i < count && pchan->chan; i++, pchan++) { + mbox_free_channel(pchan->chan); + devm_kfree(dev, pchan->xfers); + devm_iounmap(dev, pchan->rx_payload); + } +} + +static int scpi_remove(struct platform_device *pdev) +{ + int i; + struct device *dev = &pdev->dev; + struct scpi_drvinfo *info = platform_get_drvdata(pdev); + + scpi_info = NULL; /* stop exporting SCPI ops through get_scpi_ops */ + + of_platform_depopulate(dev); + sysfs_remove_groups(&dev->kobj, versions_groups); + scpi_free_channels(dev, info->channels, info->num_chans); + platform_set_drvdata(pdev, NULL); + + for (i = 0; i < MAX_DVFS_DOMAINS && info->dvfs[i]; i++) { + kfree(info->dvfs[i]->opps); + kfree(info->dvfs[i]); + } + devm_kfree(dev, info->channels); + devm_kfree(dev, info); + + return 0; +} + +#define MAX_SCPI_XFERS 10 +static int scpi_alloc_xfer_list(struct device *dev, struct scpi_chan *ch) +{ + int i; + struct scpi_xfer *xfers; + + xfers = devm_kzalloc(dev, MAX_SCPI_XFERS * sizeof(*xfers), GFP_KERNEL); + if (!xfers) + return -ENOMEM; + + ch->xfers = xfers; + for (i = 0; i < MAX_SCPI_XFERS; i++, xfers++) + list_add_tail(&xfers->node, &ch->xfers_list); + return 0; +} + +static int scpi_probe(struct platform_device *pdev) +{ + int count, idx, ret; + struct resource res; + struct scpi_chan *scpi_chan; + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + + scpi_info = devm_kzalloc(dev, sizeof(*scpi_info), GFP_KERNEL); + if (!scpi_info) + return -ENOMEM; + + count = of_count_phandle_with_args(np, "mboxes", "#mbox-cells"); + if (count < 0) { + dev_err(dev, "no mboxes property in '%s'\n", np->full_name); + return -ENODEV; + } + + scpi_chan = devm_kcalloc(dev, count, sizeof(*scpi_chan), GFP_KERNEL); + if (!scpi_chan) + return -ENOMEM; + + for (idx = 0; idx < count; idx++) { + resource_size_t size; + struct scpi_chan *pchan = scpi_chan + idx; + struct mbox_client *cl = &pchan->cl; + struct device_node *shmem = of_parse_phandle(np, "shmem", idx); + + if (of_address_to_resource(shmem, 0, &res)) { + dev_err(dev, "failed to get SCPI payload mem resource\n"); + ret = -EINVAL; + goto err; + } + + size = resource_size(&res); + pchan->rx_payload = devm_ioremap(dev, res.start, size); + if (!pchan->rx_payload) { + dev_err(dev, "failed to ioremap SCPI payload\n"); + ret = -EADDRNOTAVAIL; + goto err; + } + pchan->tx_payload = pchan->rx_payload + (size >> 1); + + cl->dev = dev; + cl->rx_callback = scpi_handle_remote_msg; + cl->tx_prepare = scpi_tx_prepare; + cl->tx_block = true; + cl->tx_tout = 50; + cl->knows_txdone = false; /* controller can't ack */ + + INIT_LIST_HEAD(&pchan->rx_pending); + INIT_LIST_HEAD(&pchan->xfers_list); + spin_lock_init(&pchan->rx_lock); + mutex_init(&pchan->xfers_lock); + + ret = scpi_alloc_xfer_list(dev, pchan); + if (!ret) { + pchan->chan = mbox_request_channel(cl, idx); + if (!IS_ERR(pchan->chan)) + continue; + ret = PTR_ERR(pchan->chan); + if (ret != -EPROBE_DEFER) + dev_err(dev, "failed to get channel%d err %d\n", + idx, ret); + } +err: + scpi_free_channels(dev, scpi_chan, idx); + scpi_info = NULL; + return ret; + } + + scpi_info->channels = scpi_chan; + scpi_info->num_chans = count; + platform_set_drvdata(pdev, scpi_info); + + ret = scpi_init_versions(scpi_info); + if (ret) { + dev_err(dev, "incorrect or no SCP firmware found\n"); + scpi_remove(pdev); + return ret; + } + + _dev_info(dev, "SCP Protocol %d.%d Firmware %d.%d.%d version\n", + PROTOCOL_REV_MAJOR(scpi_info->protocol_version), + PROTOCOL_REV_MINOR(scpi_info->protocol_version), + FW_REV_MAJOR(scpi_info->firmware_version), + FW_REV_MINOR(scpi_info->firmware_version), + FW_REV_PATCH(scpi_info->firmware_version)); + scpi_info->scpi_ops = &scpi_ops; + + ret = sysfs_create_groups(&dev->kobj, versions_groups); + if (ret) + dev_err(dev, "unable to create sysfs version group\n"); + + return of_platform_populate(dev->of_node, NULL, NULL, dev); +} + +static const struct of_device_id scpi_of_match[] = { + {.compatible = "arm,scpi"}, + {}, +}; + +MODULE_DEVICE_TABLE(of, scpi_of_match); + +static struct platform_driver scpi_driver = { + .driver = { + .name = "scpi_protocol", + .of_match_table = scpi_of_match, + }, + .probe = scpi_probe, + .remove = scpi_remove, +}; +module_platform_driver(scpi_driver); + +MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>"); +MODULE_DESCRIPTION("ARM SCPI mailbox protocol driver"); +MODULE_LICENSE("GPL v2"); diff --git a/include/linux/scpi_protocol.h b/include/linux/scpi_protocol.h new file mode 100644 index 000000000000..e7169cd54e19 --- /dev/null +++ b/include/linux/scpi_protocol.h @@ -0,0 +1,61 @@ +/* + * SCPI Message Protocol driver header + * + * Copyright (C) 2014 ARM Ltd. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see <http://www.gnu.org/licenses/>. + */ +#include <linux/types.h> + +struct scpi_opp { + u32 freq; + u32 m_volt; +} __packed; + +struct scpi_dvfs_info { + unsigned int count; + unsigned int latency; /* in nanoseconds */ + struct scpi_opp *opps; +}; + +/** + * struct scpi_ops - represents the various operations provided + * by SCP through SCPI message protocol + * @get_version: returns the major and minor revision on the SCPI + * message protocol + * @clk_get_range: gets clock range limit(min - max in Hz) + * @clk_get_val: gets clock value(in Hz) + * @clk_set_val: sets the clock value, setting to 0 will disable the + * clock (if supported) + * @dvfs_get_idx: gets the Operating Point of the given power domain. + * OPP is an index to the list return by @dvfs_get_info + * @dvfs_set_idx: sets the Operating Point of the given power domain. + * OPP is an index to the list return by @dvfs_get_info + * @dvfs_get_info: returns the DVFS capabilities of the given power + * domain. It includes the OPP list and the latency information + */ +struct scpi_ops { + u32 (*get_version)(void); + int (*clk_get_range)(u16, unsigned long *, unsigned long *); + unsigned long (*clk_get_val)(u16); + int (*clk_set_val)(u16, unsigned long); + int (*dvfs_get_idx)(u8); + int (*dvfs_set_idx)(u8, u8); + struct scpi_dvfs_info *(*dvfs_get_info)(u8); +}; + +#if IS_ENABLED(CONFIG_ARM_SCPI_PROTOCOL) +struct scpi_ops *get_scpi_ops(void); +#else +static inline struct scpi_ops *get_scpi_ops(void) { return NULL; } +#endif |