From 80f390ea5afdf7073bba0757b1eeb8d4f833398f Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Thu, 14 May 2015 11:26:11 +0100 Subject: Documentation: add DT binding for ARM System Control and Power Interface(SCPI) protocol This patch adds devicetree binding for System Control and Power Interface (SCPI) Message Protocol used between the Application Cores(AP) and the System Control Processor(SCP). The MHU peripheral provides a mechanism for inter-processor communication between SCP's M3 processor 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. Signed-off-by: Sudeep Holla Acked-by: Mark Rutland Cc: Rob Herring CC: Jassi Brar Cc: Liviu Dudau Cc: Lorenzo Pieralisi Cc: Jon Medhurst (Tixy) Cc: devicetree@vger.kernel.org --- MAINTAINERS | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'MAINTAINERS') diff --git a/MAINTAINERS b/MAINTAINERS index 7ba7ab749c85..be7d5c14729b 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -9149,6 +9149,12 @@ W: http://www.sunplus.com S: Supported F: arch/score/ +SYSTEM CONTROL & POWER INTERFACE (SCPI) Message Protocol drivers +M: Sudeep Holla +L: linux-arm-kernel@lists.infradead.org +S: Maintained +F: Documentation/devicetree/bindings/arm/arm,scpi.txt + SCSI CDROM DRIVER M: Jens Axboe L: linux-scsi@vger.kernel.org -- cgit v1.2.3 From 8cb7cf56c9fe5412de238465b27ef35b4d2801aa Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Mon, 30 Mar 2015 10:59:52 +0100 Subject: firmware: add support for ARM System Control and Power Interface(SCPI) protocol This patch adds support for System Control and Power Interface (SCPI) Message Protocol used between the Application Cores(AP) and the System Control Processor(SCP). The MHU peripheral provides a mechanism for inter-processor communication between SCP's M3 processor 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. This protocol driver provides interface for all the client drivers using SCPI to make use of the features offered by the SCP. Signed-off-by: Sudeep Holla Reviewed-by: Jon Medhurst (Tixy) Cc: Jassi Brar Cc: Liviu Dudau Cc: Lorenzo Pieralisi --- MAINTAINERS | 2 + drivers/firmware/Kconfig | 19 ++ drivers/firmware/Makefile | 1 + drivers/firmware/arm_scpi.c | 711 ++++++++++++++++++++++++++++++++++++++++++ include/linux/scpi_protocol.h | 61 ++++ 5 files changed, 794 insertions(+) create mode 100644 drivers/firmware/arm_scpi.c create mode 100644 include/linux/scpi_protocol.h (limited to 'MAINTAINERS') diff --git a/MAINTAINERS b/MAINTAINERS index be7d5c14729b..9598821d6a37 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -9154,6 +9154,8 @@ M: Sudeep Holla 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 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 . + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#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 "); +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 . + */ +#include + +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 -- cgit v1.2.3 From cd52c2a4b5c43631e429d06dce12e08b0cab477f Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Mon, 30 Mar 2015 10:59:52 +0100 Subject: clk: add support for clocks provided by SCP(System Control Processor) On some ARM based systems, a separate Cortex-M based System Control Processor(SCP) provides the overall power, clock, reset and system control. System Control and Power Interface(SCPI) Message Protocol is defined for the communication between the Application Cores(AP) and the SCP. This patch adds support for the clocks provided by SCP using SCPI protocol. Signed-off-by: Sudeep Holla Reviewed-by: Stephen Boyd Cc: Mike Turquette Cc: Liviu Dudau Cc: Lorenzo Pieralisi Cc: Jon Medhurst (Tixy) Cc: linux-clk@vger.kernel.org --- MAINTAINERS | 1 + drivers/clk/Kconfig | 10 ++ drivers/clk/Makefile | 1 + drivers/clk/clk-scpi.c | 312 +++++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 324 insertions(+) create mode 100644 drivers/clk/clk-scpi.c (limited to 'MAINTAINERS') diff --git a/MAINTAINERS b/MAINTAINERS index 9598821d6a37..613a116ab0f4 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -9154,6 +9154,7 @@ M: Sudeep Holla L: linux-arm-kernel@lists.infradead.org S: Maintained F: Documentation/devicetree/bindings/arm/arm,scpi.txt +F: drivers/clk/clk-scpi.c F: drivers/firmware/arm_scpi.c F: include/linux/scpi_protocol.h diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig index 42f7120ca9ce..4aec54b90331 100644 --- a/drivers/clk/Kconfig +++ b/drivers/clk/Kconfig @@ -59,6 +59,16 @@ config COMMON_CLK_RK808 clocked at 32KHz each. Clkout1 is always on, Clkout2 can off by control register. +config COMMON_CLK_SCPI + tristate "Clock driver controlled via SCPI interface" + depends on ARM_SCPI_PROTOCOL || COMPILE_TEST + ---help--- + This driver provides support for clocks that are controlled + by firmware that implements the SCPI interface. + + This driver uses SCPI Message Protocol to interact with the + firmware providing all the clock controls. + config COMMON_CLK_SI5351 tristate "Clock driver for SiLabs 5351A/B/C" depends on I2C diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile index d08b3e5985be..a381431bd950 100644 --- a/drivers/clk/Makefile +++ b/drivers/clk/Makefile @@ -36,6 +36,7 @@ obj-$(CONFIG_COMMON_CLK_PALMAS) += clk-palmas.o obj-$(CONFIG_CLK_QORIQ) += clk-qoriq.o obj-$(CONFIG_COMMON_CLK_RK808) += clk-rk808.o obj-$(CONFIG_COMMON_CLK_S2MPS11) += clk-s2mps11.o +obj-$(CONFIG_COMMON_CLK_SCPI) += clk-scpi.o obj-$(CONFIG_COMMON_CLK_SI5351) += clk-si5351.o obj-$(CONFIG_COMMON_CLK_SI570) += clk-si570.o obj-$(CONFIG_COMMON_CLK_CDCE925) += clk-cdce925.o diff --git a/drivers/clk/clk-scpi.c b/drivers/clk/clk-scpi.c new file mode 100644 index 000000000000..72f0486b5de6 --- /dev/null +++ b/drivers/clk/clk-scpi.c @@ -0,0 +1,312 @@ +/* + * System Control and Power Interface (SCPI) Protocol based clock driver + * + * 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 . + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +struct scpi_clk { + u32 id; + struct clk_hw hw; + struct scpi_dvfs_info *info; + struct scpi_ops *scpi_ops; +}; + +#define to_scpi_clk(clk) container_of(clk, struct scpi_clk, hw) + +static unsigned long scpi_clk_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct scpi_clk *clk = to_scpi_clk(hw); + + return clk->scpi_ops->clk_get_val(clk->id); +} + +static long scpi_clk_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + /* + * We can't figure out what rate it will be, so just return the + * rate back to the caller. scpi_clk_recalc_rate() will be called + * after the rate is set and we'll know what rate the clock is + * running at then. + */ + return rate; +} + +static int scpi_clk_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct scpi_clk *clk = to_scpi_clk(hw); + + return clk->scpi_ops->clk_set_val(clk->id, rate); +} + +static const struct clk_ops scpi_clk_ops = { + .recalc_rate = scpi_clk_recalc_rate, + .round_rate = scpi_clk_round_rate, + .set_rate = scpi_clk_set_rate, +}; + +/* find closest match to given frequency in OPP table */ +static int __scpi_dvfs_round_rate(struct scpi_clk *clk, unsigned long rate) +{ + int idx; + u32 fmin = 0, fmax = ~0, ftmp; + const struct scpi_opp *opp = clk->info->opps; + + for (idx = 0; idx < clk->info->count; idx++, opp++) { + ftmp = opp->freq; + if (ftmp >= (u32)rate) { + if (ftmp <= fmax) + fmax = ftmp; + break; + } else if (ftmp >= fmin) { + fmin = ftmp; + } + } + return fmax != ~0 ? fmax : fmin; +} + +static unsigned long scpi_dvfs_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct scpi_clk *clk = to_scpi_clk(hw); + int idx = clk->scpi_ops->dvfs_get_idx(clk->id); + const struct scpi_opp *opp; + + if (idx < 0) + return 0; + + opp = clk->info->opps + idx; + return opp->freq; +} + +static long scpi_dvfs_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + struct scpi_clk *clk = to_scpi_clk(hw); + + return __scpi_dvfs_round_rate(clk, rate); +} + +static int __scpi_find_dvfs_index(struct scpi_clk *clk, unsigned long rate) +{ + int idx, max_opp = clk->info->count; + const struct scpi_opp *opp = clk->info->opps; + + for (idx = 0; idx < max_opp; idx++, opp++) + if (opp->freq == rate) + return idx; + return -EINVAL; +} + +static int scpi_dvfs_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct scpi_clk *clk = to_scpi_clk(hw); + int ret = __scpi_find_dvfs_index(clk, rate); + + if (ret < 0) + return ret; + return clk->scpi_ops->dvfs_set_idx(clk->id, (u8)ret); +} + +static const struct clk_ops scpi_dvfs_ops = { + .recalc_rate = scpi_dvfs_recalc_rate, + .round_rate = scpi_dvfs_round_rate, + .set_rate = scpi_dvfs_set_rate, +}; + +static const struct of_device_id scpi_clk_match[] = { + { .compatible = "arm,scpi-dvfs-clocks", .data = &scpi_dvfs_ops, }, + { .compatible = "arm,scpi-variable-clocks", .data = &scpi_clk_ops, }, + {} +}; + +static struct clk * +scpi_clk_ops_init(struct device *dev, const struct of_device_id *match, + struct scpi_clk *sclk, const char *name) +{ + struct clk_init_data init; + struct clk *clk; + unsigned long min = 0, max = 0; + + init.name = name; + init.flags = CLK_IS_ROOT; + init.num_parents = 0; + init.ops = match->data; + sclk->hw.init = &init; + sclk->scpi_ops = get_scpi_ops(); + + if (init.ops == &scpi_dvfs_ops) { + sclk->info = sclk->scpi_ops->dvfs_get_info(sclk->id); + if (IS_ERR(sclk->info)) + return NULL; + } else if (init.ops == &scpi_clk_ops) { + if (sclk->scpi_ops->clk_get_range(sclk->id, &min, &max) || !max) + return NULL; + } else { + return NULL; + } + + clk = devm_clk_register(dev, &sclk->hw); + if (!IS_ERR(clk) && max) + clk_hw_set_rate_range(&sclk->hw, min, max); + return clk; +} + +struct scpi_clk_data { + struct scpi_clk **clk; + unsigned int clk_num; +}; + +static struct clk * +scpi_of_clk_src_get(struct of_phandle_args *clkspec, void *data) +{ + struct scpi_clk *sclk; + struct scpi_clk_data *clk_data = data; + unsigned int idx = clkspec->args[0], count; + + for (count = 0; count < clk_data->clk_num; count++) { + sclk = clk_data->clk[count]; + if (idx == sclk->id) + return sclk->hw.clk; + } + + return ERR_PTR(-EINVAL); +} + +static int scpi_clk_add(struct device *dev, struct device_node *np, + const struct of_device_id *match) +{ + struct clk **clks; + int idx, count; + struct scpi_clk_data *clk_data; + + count = of_property_count_strings(np, "clock-output-names"); + if (count < 0) { + dev_err(dev, "%s: invalid clock output count\n", np->name); + return -EINVAL; + } + + clk_data = devm_kmalloc(dev, sizeof(*clk_data), GFP_KERNEL); + if (!clk_data) + return -ENOMEM; + + clk_data->clk_num = count; + clk_data->clk = devm_kcalloc(dev, count, sizeof(*clk_data->clk), + GFP_KERNEL); + if (!clk_data->clk) + return -ENOMEM; + + clks = devm_kcalloc(dev, count, sizeof(*clks), GFP_KERNEL); + if (!clks) + return -ENOMEM; + + for (idx = 0; idx < count; idx++) { + struct scpi_clk *sclk; + const char *name; + u32 val; + + sclk = devm_kzalloc(dev, sizeof(*sclk), GFP_KERNEL); + if (!sclk) + return -ENOMEM; + + if (of_property_read_string_index(np, "clock-output-names", + idx, &name)) { + dev_err(dev, "invalid clock name @ %s\n", np->name); + return -EINVAL; + } + + if (of_property_read_u32_index(np, "clock-indices", + idx, &val)) { + dev_err(dev, "invalid clock index @ %s\n", np->name); + return -EINVAL; + } + + sclk->id = val; + + clks[idx] = scpi_clk_ops_init(dev, match, sclk, name); + if (IS_ERR_OR_NULL(clks[idx])) + dev_err(dev, "failed to register clock '%s'\n", name); + else + dev_dbg(dev, "Registered clock '%s'\n", name); + clk_data->clk[idx] = sclk; + } + + return of_clk_add_provider(np, scpi_of_clk_src_get, clk_data); +} + +static int scpi_clocks_remove(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *child, *np = dev->of_node; + + for_each_available_child_of_node(np, child) + of_clk_del_provider(np); + return 0; +} + +static int scpi_clocks_probe(struct platform_device *pdev) +{ + int ret; + struct device *dev = &pdev->dev; + struct device_node *child, *np = dev->of_node; + const struct of_device_id *match; + + if (!get_scpi_ops()) + return -ENXIO; + + for_each_available_child_of_node(np, child) { + match = of_match_node(scpi_clk_match, child); + if (!match) + continue; + ret = scpi_clk_add(dev, child, match); + if (ret) { + scpi_clocks_remove(pdev); + return ret; + } + } + return 0; +} + +static const struct of_device_id scpi_clocks_ids[] = { + { .compatible = "arm,scpi-clocks", }, + {} +}; +MODULE_DEVICE_TABLE(of, scpi_clocks_ids); + +static struct platform_driver scpi_clocks_driver = { + .driver = { + .name = "scpi_clocks", + .of_match_table = scpi_clocks_ids, + }, + .probe = scpi_clocks_probe, + .remove = scpi_clocks_remove, +}; +module_platform_driver(scpi_clocks_driver); + +MODULE_AUTHOR("Sudeep Holla "); +MODULE_DESCRIPTION("ARM SCPI clock driver"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3 From 8def31034d033961a4e1f34a80f317fd7002faee Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Mon, 30 Mar 2015 10:59:52 +0100 Subject: cpufreq: arm_big_little: add SCPI interface driver On some ARM based systems, a separate Cortex-M based System Control Processor(SCP) provides the overall power, clock, reset and system control including CPU DVFS. SCPI Message Protocol is used to communicate with the SCPI. This patch adds a interface driver for adding OPPs and registering the arm_big_little cpufreq driver for such systems. Signed-off-by: Sudeep Holla Acked-by: Viresh Kumar Cc: "Rafael J. Wysocki" Cc: linux-pm@vger.kernel.org --- MAINTAINERS | 1 + drivers/cpufreq/Kconfig.arm | 10 ++++ drivers/cpufreq/Makefile | 1 + drivers/cpufreq/scpi-cpufreq.c | 124 +++++++++++++++++++++++++++++++++++++++++ 4 files changed, 136 insertions(+) create mode 100644 drivers/cpufreq/scpi-cpufreq.c (limited to 'MAINTAINERS') diff --git a/MAINTAINERS b/MAINTAINERS index 613a116ab0f4..e39ae88cf423 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -9155,6 +9155,7 @@ L: linux-arm-kernel@lists.infradead.org S: Maintained F: Documentation/devicetree/bindings/arm/arm,scpi.txt F: drivers/clk/clk-scpi.c +F: drivers/cpufreq/scpi-cpufreq.c F: drivers/firmware/arm_scpi.c F: include/linux/scpi_protocol.h diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm index cd0391e46c6d..c737f7359974 100644 --- a/drivers/cpufreq/Kconfig.arm +++ b/drivers/cpufreq/Kconfig.arm @@ -199,6 +199,16 @@ config ARM_SA1100_CPUFREQ config ARM_SA1110_CPUFREQ bool +config ARM_SCPI_CPUFREQ + tristate "SCPI based CPUfreq driver" + depends on ARM_BIG_LITTLE_CPUFREQ && ARM_SCPI_PROTOCOL + help + This adds the CPUfreq driver support for ARM big.LITTLE platforms + using SCPI protocol for CPU power management. + + This driver uses SCPI Message Protocol driver to interact with the + firmware providing the CPU DVFS functionality. + config ARM_SPEAR_CPUFREQ bool "SPEAr CPUFreq support" depends on PLAT_SPEAR diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile index 41340384f11f..ccfaa4c68a9a 100644 --- a/drivers/cpufreq/Makefile +++ b/drivers/cpufreq/Makefile @@ -72,6 +72,7 @@ obj-$(CONFIG_ARM_S3C64XX_CPUFREQ) += s3c64xx-cpufreq.o obj-$(CONFIG_ARM_S5PV210_CPUFREQ) += s5pv210-cpufreq.o obj-$(CONFIG_ARM_SA1100_CPUFREQ) += sa1100-cpufreq.o obj-$(CONFIG_ARM_SA1110_CPUFREQ) += sa1110-cpufreq.o +obj-$(CONFIG_ARM_SCPI_CPUFREQ) += scpi-cpufreq.o obj-$(CONFIG_ARM_SPEAR_CPUFREQ) += spear-cpufreq.o obj-$(CONFIG_ARM_TEGRA20_CPUFREQ) += tegra20-cpufreq.o obj-$(CONFIG_ARM_TEGRA124_CPUFREQ) += tegra124-cpufreq.o diff --git a/drivers/cpufreq/scpi-cpufreq.c b/drivers/cpufreq/scpi-cpufreq.c new file mode 100644 index 000000000000..2c3b16fd3a01 --- /dev/null +++ b/drivers/cpufreq/scpi-cpufreq.c @@ -0,0 +1,124 @@ +/* + * System Control and Power Interface (SCPI) based CPUFreq Interface driver + * + * It provides necessary ops to arm_big_little cpufreq driver. + * + * Copyright (C) 2015 ARM Ltd. + * Sudeep Holla + * + * 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. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether express or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include + +#include "arm_big_little.h" + +static struct scpi_ops *scpi_ops; + +static struct scpi_dvfs_info *scpi_get_dvfs_info(struct device *cpu_dev) +{ + u8 domain = topology_physical_package_id(cpu_dev->id); + + if (domain < 0) + return ERR_PTR(-EINVAL); + return scpi_ops->dvfs_get_info(domain); +} + +static int scpi_opp_table_ops(struct device *cpu_dev, bool remove) +{ + int idx, ret = 0; + struct scpi_opp *opp; + struct scpi_dvfs_info *info = scpi_get_dvfs_info(cpu_dev); + + if (IS_ERR(info)) + return PTR_ERR(info); + + if (!info->opps) + return -EIO; + + for (opp = info->opps, idx = 0; idx < info->count; idx++, opp++) { + if (remove) + dev_pm_opp_remove(cpu_dev, opp->freq); + else + ret = dev_pm_opp_add(cpu_dev, opp->freq, + opp->m_volt * 1000); + if (ret) { + dev_warn(cpu_dev, "failed to add opp %uHz %umV\n", + opp->freq, opp->m_volt); + while (idx-- > 0) + dev_pm_opp_remove(cpu_dev, (--opp)->freq); + return ret; + } + } + return ret; +} + +static int scpi_get_transition_latency(struct device *cpu_dev) +{ + struct scpi_dvfs_info *info = scpi_get_dvfs_info(cpu_dev); + + if (IS_ERR(info)) + return PTR_ERR(info); + return info->latency; +} + +static int scpi_init_opp_table(struct device *cpu_dev) +{ + return scpi_opp_table_ops(cpu_dev, false); +} + +static void scpi_free_opp_table(struct device *cpu_dev) +{ + scpi_opp_table_ops(cpu_dev, true); +} + +static struct cpufreq_arm_bL_ops scpi_cpufreq_ops = { + .name = "scpi", + .get_transition_latency = scpi_get_transition_latency, + .init_opp_table = scpi_init_opp_table, + .free_opp_table = scpi_free_opp_table, +}; + +static int scpi_cpufreq_probe(struct platform_device *pdev) +{ + scpi_ops = get_scpi_ops(); + if (!scpi_ops) + return -EIO; + + return bL_cpufreq_register(&scpi_cpufreq_ops); +} + +static int scpi_cpufreq_remove(struct platform_device *pdev) +{ + bL_cpufreq_unregister(&scpi_cpufreq_ops); + scpi_ops = NULL; + return 0; +} + +static struct platform_driver scpi_cpufreq_platdrv = { + .driver = { + .name = "scpi-cpufreq", + .owner = THIS_MODULE, + }, + .probe = scpi_cpufreq_probe, + .remove = scpi_cpufreq_remove, +}; +module_platform_driver(scpi_cpufreq_platdrv); + +MODULE_AUTHOR("Sudeep Holla "); +MODULE_DESCRIPTION("ARM SCPI CPUFreq interface driver"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3