Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC driver updates from Arnd Bergmann:
 "The main addition this time around is the new ARM "SCMI" framework,
  which is the latest in a series of standards coming from ARM to do
  power management in a platform independent way.

  This has been through many review cycles, and it relies on a rather
  interesting way of using the mailbox subsystem, but in the end I
  agreed that Sudeep's version was the best we could do after all.

  Other changes include:

   - the ARM CCN driver is moved out of drivers/bus into drivers/perf,
     which makes more sense. Similarly, the performance monitoring
     portion of the CCI driver are moved the same way and cleaned up a
     little more.

   - a series of updates to the SCPI framework

   - support for the Mediatek mt7623a SoC in drivers/soc

   - support for additional NVIDIA Tegra hardware in drivers/soc

   - a new reset driver for Socionext Uniphier

   - lesser bug fixes in drivers/soc, drivers/tee, drivers/memory, and
     drivers/firmware and drivers/reset across platforms"

* tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (87 commits)
  reset: uniphier: add ethernet reset control support for PXs3
  reset: stm32mp1: Enable stm32mp1 reset driver
  dt-bindings: reset: add STM32MP1 resets
  reset: uniphier: add Pro4/Pro5/PXs2 audio systems reset control
  reset: imx7: add 'depends on HAS_IOMEM' to fix unmet dependency
  reset: modify the way reset lookup works for board files
  reset: add support for non-DT systems
  clk: scmi: use devm_of_clk_add_hw_provider() API and drop scmi_clocks_remove
  firmware: arm_scmi: prevent accessing rate_discrete uninitialized
  hwmon: (scmi) return -EINVAL when sensor information is unavailable
  amlogic: meson-gx-socinfo: Update soc ids
  soc/tegra: pmc: Use the new reset APIs to manage reset controllers
  soc: mediatek: update power domain data of MT2712
  dt-bindings: soc: update MT2712 power dt-bindings
  cpufreq: scmi: add thermal dependency
  soc: mediatek: fix the mistaken pointer accessed when subdomains are added
  soc: mediatek: add SCPSYS power domain driver for MediaTek MT7623A SoC
  soc: mediatek: avoid hardcoded value with bus_prot_mask
  dt-bindings: soc: add header files required for MT7623A SCPSYS dt-binding
  dt-bindings: soc: add SCPSYS binding for MT7623 and MT7623A SoC
  ...

15 files changed, 3121 insertions, 214 deletions

diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig
index b7c748248e53..6e83880046d7 100644
--- a/drivers/firmware/Kconfig
+++ b/drivers/firmware/Kconfig
@@ -19,6 +19,40 @@ config ARM_PSCI_CHECKER
 	  on and off through hotplug, so for now torture tests and PSCI checker
 	  are mutually exclusive.
 
+config ARM_SCMI_PROTOCOL
+	bool "ARM System Control and Management Interface (SCMI) Message Protocol"
+	depends on ARM || ARM64 || COMPILE_TEST
+	depends on MAILBOX
+	help
+	  ARM System Control and Management Interface (SCMI) protocol is a
+	  set of operating system-independent software interfaces that are
+	  used in system management. SCMI is extensible and currently provides
+	  interfaces for: Discovery and self-description of the interfaces
+	  it supports, Power domain management which is the ability to place
+	  a given device or domain into the various power-saving states that
+	  it supports, Performance management which is the ability to control
+	  the performance of a domain that is composed of compute engines
+	  such as application processors and other accelerators, Clock
+	  management which is the ability to set and inquire rates on platform
+	  managed clocks and Sensor management which is the ability to read
+	  sensor data, and be notified of sensor value.
+
+	  This protocol library provides interface for all the client drivers
+	  making use of the features offered by the SCMI.
+
+config ARM_SCMI_POWER_DOMAIN
+	tristate "SCMI power domain driver"
+	depends on ARM_SCMI_PROTOCOL || (COMPILE_TEST && OF)
+	default y
+	select PM_GENERIC_DOMAINS if PM
+	help
+	  This enables support for the SCMI power domains which can be
+	  enabled or disabled via the SCP firmware
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called scmi_pm_domain. Note this may needed early in boot
+	  before rootfs may be available.
+
 config ARM_SCPI_PROTOCOL
 	tristate "ARM System Control and Power Interface (SCPI) Message Protocol"
 	depends on ARM || ARM64 || COMPILE_TEST
diff --git a/drivers/firmware/Makefile b/drivers/firmware/Makefile
index b248238ddc6a..e18a041cfc53 100644
--- a/drivers/firmware/Makefile
+++ b/drivers/firmware/Makefile
@@ -25,6 +25,7 @@ obj-$(CONFIG_QCOM_SCM_32)	+= qcom_scm-32.o
 CFLAGS_qcom_scm-32.o :=$(call as-instr,.arch armv7-a\n.arch_extension sec,-DREQUIRES_SEC=1) -march=armv7-a
 obj-$(CONFIG_TI_SCI_PROTOCOL)	+= ti_sci.o
 
+obj-$(CONFIG_ARM_SCMI_PROTOCOL)	+= arm_scmi/
 obj-y				+= broadcom/
 obj-y				+= meson/
 obj-$(CONFIG_GOOGLE_FIRMWARE)	+= google/
diff --git a/drivers/firmware/arm_scmi/Makefile b/drivers/firmware/arm_scmi/Makefile
new file mode 100644
index 000000000000..99e36c580fbc
--- /dev/null
+++ b/drivers/firmware/arm_scmi/Makefile
@@ -0,0 +1,5 @@
+obj-y	= scmi-bus.o scmi-driver.o scmi-protocols.o
+scmi-bus-y = bus.o
+scmi-driver-y = driver.o
+scmi-protocols-y = base.o clock.o perf.o power.o sensors.o
+obj-$(CONFIG_ARM_SCMI_POWER_DOMAIN) += scmi_pm_domain.o
diff --git a/drivers/firmware/arm_scmi/base.c b/drivers/firmware/arm_scmi/base.c
new file mode 100644
index 000000000000..0d3806c0d432
--- /dev/null
+++ b/drivers/firmware/arm_scmi/base.c
@@ -0,0 +1,253 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * System Control and Management Interface (SCMI) Base Protocol
+ *
+ * Copyright (C) 2018 ARM Ltd.
+ */
+
+#include "common.h"
+
+enum scmi_base_protocol_cmd {
+	BASE_DISCOVER_VENDOR = 0x3,
+	BASE_DISCOVER_SUB_VENDOR = 0x4,
+	BASE_DISCOVER_IMPLEMENT_VERSION = 0x5,
+	BASE_DISCOVER_LIST_PROTOCOLS = 0x6,
+	BASE_DISCOVER_AGENT = 0x7,
+	BASE_NOTIFY_ERRORS = 0x8,
+};
+
+struct scmi_msg_resp_base_attributes {
+	u8 num_protocols;
+	u8 num_agents;
+	__le16 reserved;
+};
+
+/**
+ * scmi_base_attributes_get() - gets the implementation details
+ *	that are associated with the base protocol.
+ *
+ * @handle - SCMI entity handle
+ *
+ * Return: 0 on success, else appropriate SCMI error.
+ */
+static int scmi_base_attributes_get(const struct scmi_handle *handle)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_msg_resp_base_attributes *attr_info;
+	struct scmi_revision_info *rev = handle->version;
+
+	ret = scmi_one_xfer_init(handle, PROTOCOL_ATTRIBUTES,
+				 SCMI_PROTOCOL_BASE, 0, sizeof(*attr_info), &t);
+	if (ret)
+		return ret;
+
+	ret = scmi_do_xfer(handle, t);
+	if (!ret) {
+		attr_info = t->rx.buf;
+		rev->num_protocols = attr_info->num_protocols;
+		rev->num_agents = attr_info->num_agents;
+	}
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+/**
+ * scmi_base_vendor_id_get() - gets vendor/subvendor identifier ASCII string.
+ *
+ * @handle - SCMI entity handle
+ * @sub_vendor - specify true if sub-vendor ID is needed
+ *
+ * Return: 0 on success, else appropriate SCMI error.
+ */
+static int
+scmi_base_vendor_id_get(const struct scmi_handle *handle, bool sub_vendor)
+{
+	u8 cmd;
+	int ret, size;
+	char *vendor_id;
+	struct scmi_xfer *t;
+	struct scmi_revision_info *rev = handle->version;
+
+	if (sub_vendor) {
+		cmd = BASE_DISCOVER_SUB_VENDOR;
+		vendor_id = rev->sub_vendor_id;
+		size = ARRAY_SIZE(rev->sub_vendor_id);
+	} else {
+		cmd = BASE_DISCOVER_VENDOR;
+		vendor_id = rev->vendor_id;
+		size = ARRAY_SIZE(rev->vendor_id);
+	}
+
+	ret = scmi_one_xfer_init(handle, cmd, SCMI_PROTOCOL_BASE, 0, size, &t);
+	if (ret)
+		return ret;
+
+	ret = scmi_do_xfer(handle, t);
+	if (!ret)
+		memcpy(vendor_id, t->rx.buf, size);
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+/**
+ * scmi_base_implementation_version_get() - gets a vendor-specific
+ *	implementation 32-bit version. The format of the version number is
+ *	vendor-specific
+ *
+ * @handle - SCMI entity handle
+ *
+ * Return: 0 on success, else appropriate SCMI error.
+ */
+static int
+scmi_base_implementation_version_get(const struct scmi_handle *handle)
+{
+	int ret;
+	__le32 *impl_ver;
+	struct scmi_xfer *t;
+	struct scmi_revision_info *rev = handle->version;
+
+	ret = scmi_one_xfer_init(handle, BASE_DISCOVER_IMPLEMENT_VERSION,
+				 SCMI_PROTOCOL_BASE, 0, sizeof(*impl_ver), &t);
+	if (ret)
+		return ret;
+
+	ret = scmi_do_xfer(handle, t);
+	if (!ret) {
+		impl_ver = t->rx.buf;
+		rev->impl_ver = le32_to_cpu(*impl_ver);
+	}
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+/**
+ * scmi_base_implementation_list_get() - gets the list of protocols it is
+ *	OSPM is allowed to access
+ *
+ * @handle - SCMI entity handle
+ * @protocols_imp - pointer to hold the list of protocol identifiers
+ *
+ * Return: 0 on success, else appropriate SCMI error.
+ */
+static int scmi_base_implementation_list_get(const struct scmi_handle *handle,
+					     u8 *protocols_imp)
+{
+	u8 *list;
+	int ret, loop;
+	struct scmi_xfer *t;
+	__le32 *num_skip, *num_ret;
+	u32 tot_num_ret = 0, loop_num_ret;
+	struct device *dev = handle->dev;
+
+	ret = scmi_one_xfer_init(handle, BASE_DISCOVER_LIST_PROTOCOLS,
+				 SCMI_PROTOCOL_BASE, sizeof(*num_skip), 0, &t);
+	if (ret)
+		return ret;
+
+	num_skip = t->tx.buf;
+	num_ret = t->rx.buf;
+	list = t->rx.buf + sizeof(*num_ret);
+
+	do {
+		/* Set the number of protocols to be skipped/already read */
+		*num_skip = cpu_to_le32(tot_num_ret);
+
+		ret = scmi_do_xfer(handle, t);
+		if (ret)
+			break;
+
+		loop_num_ret = le32_to_cpu(*num_ret);
+		if (tot_num_ret + loop_num_ret > MAX_PROTOCOLS_IMP) {
+			dev_err(dev, "No. of Protocol > MAX_PROTOCOLS_IMP");
+			break;
+		}
+
+		for (loop = 0; loop < loop_num_ret; loop++)
+			protocols_imp[tot_num_ret + loop] = *(list + loop);
+
+		tot_num_ret += loop_num_ret;
+	} while (loop_num_ret);
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+/**
+ * scmi_base_discover_agent_get() - discover the name of an agent
+ *
+ * @handle - SCMI entity handle
+ * @id - Agent identifier
+ * @name - Agent identifier ASCII string
+ *
+ * An agent id of 0 is reserved to identify the platform itself.
+ * Generally operating system is represented as "OSPM"
+ *
+ * Return: 0 on success, else appropriate SCMI error.
+ */
+static int scmi_base_discover_agent_get(const struct scmi_handle *handle,
+					int id, char *name)
+{
+	int ret;
+	struct scmi_xfer *t;
+
+	ret = scmi_one_xfer_init(handle, BASE_DISCOVER_AGENT,
+				 SCMI_PROTOCOL_BASE, sizeof(__le32),
+				 SCMI_MAX_STR_SIZE, &t);
+	if (ret)
+		return ret;
+
+	*(__le32 *)t->tx.buf = cpu_to_le32(id);
+
+	ret = scmi_do_xfer(handle, t);
+	if (!ret)
+		memcpy(name, t->rx.buf, SCMI_MAX_STR_SIZE);
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+int scmi_base_protocol_init(struct scmi_handle *h)
+{
+	int id, ret;
+	u8 *prot_imp;
+	u32 version;
+	char name[SCMI_MAX_STR_SIZE];
+	const struct scmi_handle *handle = h;
+	struct device *dev = handle->dev;
+	struct scmi_revision_info *rev = handle->version;
+
+	ret = scmi_version_get(handle, SCMI_PROTOCOL_BASE, &version);
+	if (ret)
+		return ret;
+
+	prot_imp = devm_kcalloc(dev, MAX_PROTOCOLS_IMP, sizeof(u8), GFP_KERNEL);
+	if (!prot_imp)
+		return -ENOMEM;
+
+	rev->major_ver = PROTOCOL_REV_MAJOR(version),
+	rev->minor_ver = PROTOCOL_REV_MINOR(version);
+
+	scmi_base_attributes_get(handle);
+	scmi_base_vendor_id_get(handle, false);
+	scmi_base_vendor_id_get(handle, true);
+	scmi_base_implementation_version_get(handle);
+	scmi_base_implementation_list_get(handle, prot_imp);
+	scmi_setup_protocol_implemented(handle, prot_imp);
+
+	dev_info(dev, "SCMI Protocol v%d.%d '%s:%s' Firmware version 0x%x\n",
+		 rev->major_ver, rev->minor_ver, rev->vendor_id,
+		 rev->sub_vendor_id, rev->impl_ver);
+	dev_dbg(dev, "Found %d protocol(s) %d agent(s)\n", rev->num_protocols,
+		rev->num_agents);
+
+	for (id = 0; id < rev->num_agents; id++) {
+		scmi_base_discover_agent_get(handle, id, name);
+		dev_dbg(dev, "Agent %d: %s\n", id, name);
+	}
+
+	return 0;
+}
diff --git a/drivers/firmware/arm_scmi/bus.c b/drivers/firmware/arm_scmi/bus.c
new file mode 100644
index 000000000000..f2760a596c28
--- /dev/null
+++ b/drivers/firmware/arm_scmi/bus.c
@@ -0,0 +1,221 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * System Control and Management Interface (SCMI) Message Protocol bus layer
+ *
+ * Copyright (C) 2018 ARM Ltd.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+
+#include "common.h"
+
+static DEFINE_IDA(scmi_bus_id);
+static DEFINE_IDR(scmi_protocols);
+static DEFINE_SPINLOCK(protocol_lock);
+
+static const struct scmi_device_id *
+scmi_dev_match_id(struct scmi_device *scmi_dev, struct scmi_driver *scmi_drv)
+{
+	const struct scmi_device_id *id = scmi_drv->id_table;
+
+	if (!id)
+		return NULL;
+
+	for (; id->protocol_id; id++)
+		if (id->protocol_id == scmi_dev->protocol_id)
+			return id;
+
+	return NULL;
+}
+
+static int scmi_dev_match(struct device *dev, struct device_driver *drv)
+{
+	struct scmi_driver *scmi_drv = to_scmi_driver(drv);
+	struct scmi_device *scmi_dev = to_scmi_dev(dev);
+	const struct scmi_device_id *id;
+
+	id = scmi_dev_match_id(scmi_dev, scmi_drv);
+	if (id)
+		return 1;
+
+	return 0;
+}
+
+static int scmi_protocol_init(int protocol_id, struct scmi_handle *handle)
+{
+	scmi_prot_init_fn_t fn = idr_find(&scmi_protocols, protocol_id);
+
+	if (unlikely(!fn))
+		return -EINVAL;
+	return fn(handle);
+}
+
+static int scmi_dev_probe(struct device *dev)
+{
+	struct scmi_driver *scmi_drv = to_scmi_driver(dev->driver);
+	struct scmi_device *scmi_dev = to_scmi_dev(dev);
+	const struct scmi_device_id *id;
+	int ret;
+
+	id = scmi_dev_match_id(scmi_dev, scmi_drv);
+	if (!id)
+		return -ENODEV;
+
+	if (!scmi_dev->handle)
+		return -EPROBE_DEFER;
+
+	ret = scmi_protocol_init(scmi_dev->protocol_id, scmi_dev->handle);
+	if (ret)
+		return ret;
+
+	return scmi_drv->probe(scmi_dev);
+}
+
+static int scmi_dev_remove(struct device *dev)
+{
+	struct scmi_driver *scmi_drv = to_scmi_driver(dev->driver);
+	struct scmi_device *scmi_dev = to_scmi_dev(dev);
+
+	if (scmi_drv->remove)
+		scmi_drv->remove(scmi_dev);
+
+	return 0;
+}
+
+static struct bus_type scmi_bus_type = {
+	.name =	"scmi_protocol",
+	.match = scmi_dev_match,
+	.probe = scmi_dev_probe,
+	.remove = scmi_dev_remove,
+};
+
+int scmi_driver_register(struct scmi_driver *driver, struct module *owner,
+			 const char *mod_name)
+{
+	int retval;
+
+	driver->driver.bus = &scmi_bus_type;
+	driver->driver.name = driver->name;
+	driver->driver.owner = owner;
+	driver->driver.mod_name = mod_name;
+
+	retval = driver_register(&driver->driver);
+	if (!retval)
+		pr_debug("registered new scmi driver %s\n", driver->name);
+
+	return retval;
+}
+EXPORT_SYMBOL_GPL(scmi_driver_register);
+
+void scmi_driver_unregister(struct scmi_driver *driver)
+{
+	driver_unregister(&driver->driver);
+}
+EXPORT_SYMBOL_GPL(scmi_driver_unregister);
+
+struct scmi_device *
+scmi_device_create(struct device_node *np, struct device *parent, int protocol)
+{
+	int id, retval;
+	struct scmi_device *scmi_dev;
+
+	id = ida_simple_get(&scmi_bus_id, 1, 0, GFP_KERNEL);
+	if (id < 0)
+		return NULL;
+
+	scmi_dev = kzalloc(sizeof(*scmi_dev), GFP_KERNEL);
+	if (!scmi_dev)
+		goto no_mem;
+
+	scmi_dev->id = id;
+	scmi_dev->protocol_id = protocol;
+	scmi_dev->dev.parent = parent;
+	scmi_dev->dev.of_node = np;
+	scmi_dev->dev.bus = &scmi_bus_type;
+	dev_set_name(&scmi_dev->dev, "scmi_dev.%d", id);
+
+	retval = device_register(&scmi_dev->dev);
+	if (!retval)
+		return scmi_dev;
+
+	put_device(&scmi_dev->dev);
+	kfree(scmi_dev);
+no_mem:
+	ida_simple_remove(&scmi_bus_id, id);
+	return NULL;
+}
+
+void scmi_device_destroy(struct scmi_device *scmi_dev)
+{
+	scmi_handle_put(scmi_dev->handle);
+	device_unregister(&scmi_dev->dev);
+	ida_simple_remove(&scmi_bus_id, scmi_dev->id);
+	kfree(scmi_dev);
+}
+
+void scmi_set_handle(struct scmi_device *scmi_dev)
+{
+	scmi_dev->handle = scmi_handle_get(&scmi_dev->dev);
+}
+
+int scmi_protocol_register(int protocol_id, scmi_prot_init_fn_t fn)
+{
+	int ret;
+
+	spin_lock(&protocol_lock);
+	ret = idr_alloc(&scmi_protocols, fn, protocol_id, protocol_id + 1,
+			GFP_ATOMIC);
+	if (ret != protocol_id)
+		pr_err("unable to allocate SCMI idr slot, err %d\n", ret);
+	spin_unlock(&protocol_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(scmi_protocol_register);
+
+void scmi_protocol_unregister(int protocol_id)
+{
+	spin_lock(&protocol_lock);
+	idr_remove(&scmi_protocols, protocol_id);
+	spin_unlock(&protocol_lock);
+}
+EXPORT_SYMBOL_GPL(scmi_protocol_unregister);
+
+static int __scmi_devices_unregister(struct device *dev, void *data)
+{
+	struct scmi_device *scmi_dev = to_scmi_dev(dev);
+
+	scmi_device_destroy(scmi_dev);
+	return 0;
+}
+
+static void scmi_devices_unregister(void)
+{
+	bus_for_each_dev(&scmi_bus_type, NULL, NULL, __scmi_devices_unregister);
+}
+
+static int __init scmi_bus_init(void)
+{
+	int retval;
+
+	retval = bus_register(&scmi_bus_type);
+	if (retval)
+		pr_err("scmi protocol bus register failed (%d)\n", retval);
+
+	return retval;
+}
+subsys_initcall(scmi_bus_init);
+
+static void __exit scmi_bus_exit(void)
+{
+	scmi_devices_unregister();
+	bus_unregister(&scmi_bus_type);
+	ida_destroy(&scmi_bus_id);
+}
+module_exit(scmi_bus_exit);
diff --git a/drivers/firmware/arm_scmi/clock.c b/drivers/firmware/arm_scmi/clock.c
new file mode 100644
index 000000000000..e6f17825db79
--- /dev/null
+++ b/drivers/firmware/arm_scmi/clock.c
@@ -0,0 +1,343 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * System Control and Management Interface (SCMI) Clock Protocol
+ *
+ * Copyright (C) 2018 ARM Ltd.
+ */
+
+#include "common.h"
+
+enum scmi_clock_protocol_cmd {
+	CLOCK_ATTRIBUTES = 0x3,
+	CLOCK_DESCRIBE_RATES = 0x4,
+	CLOCK_RATE_SET = 0x5,
+	CLOCK_RATE_GET = 0x6,
+	CLOCK_CONFIG_SET = 0x7,
+};
+
+struct scmi_msg_resp_clock_protocol_attributes {
+	__le16 num_clocks;
+	u8 max_async_req;
+	u8 reserved;
+};
+
+struct scmi_msg_resp_clock_attributes {
+	__le32 attributes;
+#define	CLOCK_ENABLE	BIT(0)
+	    u8 name[SCMI_MAX_STR_SIZE];
+};
+
+struct scmi_clock_set_config {
+	__le32 id;
+	__le32 attributes;
+};
+
+struct scmi_msg_clock_describe_rates {
+	__le32 id;
+	__le32 rate_index;
+};
+
+struct scmi_msg_resp_clock_describe_rates {
+	__le32 num_rates_flags;
+#define NUM_RETURNED(x)		((x) & 0xfff)
+#define RATE_DISCRETE(x)	!((x) & BIT(12))
+#define NUM_REMAINING(x)	((x) >> 16)
+	struct {
+		__le32 value_low;
+		__le32 value_high;
+	} rate[0];
+#define RATE_TO_U64(X)		\
+({				\
+	typeof(X) x = (X);	\
+	le32_to_cpu((x).value_low) | (u64)le32_to_cpu((x).value_high) << 32; \
+})
+};
+
+struct scmi_clock_set_rate {
+	__le32 flags;
+#define CLOCK_SET_ASYNC		BIT(0)
+#define CLOCK_SET_DELAYED	BIT(1)
+#define CLOCK_SET_ROUND_UP	BIT(2)
+#define CLOCK_SET_ROUND_AUTO	BIT(3)
+	__le32 id;
+	__le32 value_low;
+	__le32 value_high;
+};
+
+struct clock_info {
+	int num_clocks;
+	int max_async_req;
+	struct scmi_clock_info *clk;
+};
+
+static int scmi_clock_protocol_attributes_get(const struct scmi_handle *handle,
+					      struct clock_info *ci)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_msg_resp_clock_protocol_attributes *attr;
+
+	ret = scmi_one_xfer_init(handle, PROTOCOL_ATTRIBUTES,
+				 SCMI_PROTOCOL_CLOCK, 0, sizeof(*attr), &t);
+	if (ret)
+		return ret;
+
+	attr = t->rx.buf;
+
+	ret = scmi_do_xfer(handle, t);
+	if (!ret) {
+		ci->num_clocks = le16_to_cpu(attr->num_clocks);
+		ci->max_async_req = attr->max_async_req;
+	}
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static int scmi_clock_attributes_get(const struct scmi_handle *handle,
+				     u32 clk_id, struct scmi_clock_info *clk)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_msg_resp_clock_attributes *attr;
+
+	ret = scmi_one_xfer_init(handle, CLOCK_ATTRIBUTES, SCMI_PROTOCOL_CLOCK,
+				 sizeof(clk_id), sizeof(*attr), &t);
+	if (ret)
+		return ret;
+
+	*(__le32 *)t->tx.buf = cpu_to_le32(clk_id);
+	attr = t->rx.buf;
+
+	ret = scmi_do_xfer(handle, t);
+	if (!ret)
+		memcpy(clk->name, attr->name, SCMI_MAX_STR_SIZE);
+	else
+		clk->name[0] = '\0';
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static int
+scmi_clock_describe_rates_get(const struct scmi_handle *handle, u32 clk_id,
+			      struct scmi_clock_info *clk)
+{
+	u64 *rate;
+	int ret, cnt;
+	bool rate_discrete = false;
+	u32 tot_rate_cnt = 0, rates_flag;
+	u16 num_returned, num_remaining;
+	struct scmi_xfer *t;
+	struct scmi_msg_clock_describe_rates *clk_desc;
+	struct scmi_msg_resp_clock_describe_rates *rlist;
+
+	ret = scmi_one_xfer_init(handle, CLOCK_DESCRIBE_RATES,
+				 SCMI_PROTOCOL_CLOCK, sizeof(*clk_desc), 0, &t);
+	if (ret)
+		return ret;
+
+	clk_desc = t->tx.buf;
+	rlist = t->rx.buf;
+
+	do {
+		clk_desc->id = cpu_to_le32(clk_id);
+		/* Set the number of rates to be skipped/already read */
+		clk_desc->rate_index = cpu_to_le32(tot_rate_cnt);
+
+		ret = scmi_do_xfer(handle, t);
+		if (ret)
+			goto err;
+
+		rates_flag = le32_to_cpu(rlist->num_rates_flags);
+		num_remaining = NUM_REMAINING(rates_flag);
+		rate_discrete = RATE_DISCRETE(rates_flag);
+		num_returned = NUM_RETURNED(rates_flag);
+
+		if (tot_rate_cnt + num_returned > SCMI_MAX_NUM_RATES) {
+			dev_err(handle->dev, "No. of rates > MAX_NUM_RATES");
+			break;
+		}
+
+		if (!rate_discrete) {
+			clk->range.min_rate = RATE_TO_U64(rlist->rate[0]);
+			clk->range.max_rate = RATE_TO_U64(rlist->rate[1]);
+			clk->range.step_size = RATE_TO_U64(rlist->rate[2]);
+			dev_dbg(handle->dev, "Min %llu Max %llu Step %llu Hz\n",
+				clk->range.min_rate, clk->range.max_rate,
+				clk->range.step_size);
+			break;
+		}
+
+		rate = &clk->list.rates[tot_rate_cnt];
+		for (cnt = 0; cnt < num_returned; cnt++, rate++) {
+			*rate = RATE_TO_U64(rlist->rate[cnt]);
+			dev_dbg(handle->dev, "Rate %llu Hz\n", *rate);
+		}
+
+		tot_rate_cnt += num_returned;
+		/*
+		 * check for both returned and remaining to avoid infinite
+		 * loop due to buggy firmware
+		 */
+	} while (num_returned && num_remaining);
+
+	if (rate_discrete)
+		clk->list.num_rates = tot_rate_cnt;
+
+err:
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static int
+scmi_clock_rate_get(const struct scmi_handle *handle, u32 clk_id, u64 *value)
+{
+	int ret;
+	struct scmi_xfer *t;
+
+	ret = scmi_one_xfer_init(handle, CLOCK_RATE_GET, SCMI_PROTOCOL_CLOCK,
+				 sizeof(__le32), sizeof(u64), &t);
+	if (ret)
+		return ret;
+
+	*(__le32 *)t->tx.buf = cpu_to_le32(clk_id);
+
+	ret = scmi_do_xfer(handle, t);
+	if (!ret) {
+		__le32 *pval = t->rx.buf;
+
+		*value = le32_to_cpu(*pval);
+		*value |= (u64)le32_to_cpu(*(pval + 1)) << 32;
+	}
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static int scmi_clock_rate_set(const struct scmi_handle *handle, u32 clk_id,
+			       u32 config, u64 rate)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_clock_set_rate *cfg;
+
+	ret = scmi_one_xfer_init(handle, CLOCK_RATE_SET, SCMI_PROTOCOL_CLOCK,
+				 sizeof(*cfg), 0, &t);
+	if (ret)
+		return ret;
+
+	cfg = t->tx.buf;
+	cfg->flags = cpu_to_le32(config);
+	cfg->id = cpu_to_le32(clk_id);
+	cfg->value_low = cpu_to_le32(rate & 0xffffffff);
+	cfg->value_high = cpu_to_le32(rate >> 32);
+
+	ret = scmi_do_xfer(handle, t);
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static int
+scmi_clock_config_set(const struct scmi_handle *handle, u32 clk_id, u32 config)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_clock_set_config *cfg;
+
+	ret = scmi_one_xfer_init(handle, CLOCK_CONFIG_SET, SCMI_PROTOCOL_CLOCK,
+				 sizeof(*cfg), 0, &t);
+	if (ret)
+		return ret;
+
+	cfg = t->tx.buf;
+	cfg->id = cpu_to_le32(clk_id);
+	cfg->attributes = cpu_to_le32(config);
+
+	ret = scmi_do_xfer(handle, t);
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static int scmi_clock_enable(const struct scmi_handle *handle, u32 clk_id)
+{
+	return scmi_clock_config_set(handle, clk_id, CLOCK_ENABLE);
+}
+
+static int scmi_clock_disable(const struct scmi_handle *handle, u32 clk_id)
+{
+	return scmi_clock_config_set(handle, clk_id, 0);
+}
+
+static int scmi_clock_count_get(const struct scmi_handle *handle)
+{
+	struct clock_info *ci = handle->clk_priv;
+
+	return ci->num_clocks;
+}
+
+static const struct scmi_clock_info *
+scmi_clock_info_get(const struct scmi_handle *handle, u32 clk_id)
+{
+	struct clock_info *ci = handle->clk_priv;
+	struct scmi_clock_info *clk = ci->clk + clk_id;
+
+	if (!clk->name || !clk->name[0])
+		return NULL;
+
+	return clk;
+}
+
+static struct scmi_clk_ops clk_ops = {
+	.count_get = scmi_clock_count_get,
+	.info_get = scmi_clock_info_get,
+	.rate_get = scmi_clock_rate_get,
+	.rate_set = scmi_clock_rate_set,
+	.enable = scmi_clock_enable,
+	.disable = scmi_clock_disable,
+};
+
+static int scmi_clock_protocol_init(struct scmi_handle *handle)
+{
+	u32 version;
+	int clkid, ret;
+	struct clock_info *cinfo;
+
+	scmi_version_get(handle, SCMI_PROTOCOL_CLOCK, &version);
+
+	dev_dbg(handle->dev, "Clock Version %d.%d\n",
+		PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
+
+	cinfo = devm_kzalloc(handle->dev, sizeof(*cinfo), GFP_KERNEL);
+	if (!cinfo)
+		return -ENOMEM;
+
+	scmi_clock_protocol_attributes_get(handle, cinfo);
+
+	cinfo->clk = devm_kcalloc(handle->dev, cinfo->num_clocks,
+				  sizeof(*cinfo->clk), GFP_KERNEL);
+	if (!cinfo->clk)
+		return -ENOMEM;
+
+	for (clkid = 0; clkid < cinfo->num_clocks; clkid++) {
+		struct scmi_clock_info *clk = cinfo->clk + clkid;
+
+		ret = scmi_clock_attributes_get(handle, clkid, clk);
+		if (!ret)
+			scmi_clock_describe_rates_get(handle, clkid, clk);
+	}
+
+	handle->clk_ops = &clk_ops;
+	handle->clk_priv = cinfo;
+
+	return 0;
+}
+
+static int __init scmi_clock_init(void)
+{
+	return scmi_protocol_register(SCMI_PROTOCOL_CLOCK,
+				      &scmi_clock_protocol_init);
+}
+subsys_initcall(scmi_clock_init);
diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
new file mode 100644
index 000000000000..0c30234f9098
--- /dev/null
+++ b/drivers/firmware/arm_scmi/common.h
@@ -0,0 +1,105 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * System Control and Management Interface (SCMI) Message Protocol
+ * driver common header file containing some definitions, structures
+ * and function prototypes used in all the different SCMI protocols.
+ *
+ * Copyright (C) 2018 ARM Ltd.
+ */
+
+#include <linux/completion.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/scmi_protocol.h>
+#include <linux/types.h>
+
+#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 MAX_PROTOCOLS_IMP	16
+#define MAX_OPPS		16
+
+enum scmi_common_cmd {
+	PROTOCOL_VERSION = 0x0,
+	PROTOCOL_ATTRIBUTES = 0x1,
+	PROTOCOL_MESSAGE_ATTRIBUTES = 0x2,
+};
+
+/**
+ * struct scmi_msg_resp_prot_version - Response for a message
+ *
+ * @major_version: Major version of the ABI that firmware supports
+ * @minor_version: Minor version of the ABI that firmware supports
+ *
+ * In general, ABI version changes follow the rule that minor version increments
+ * are backward compatible. Major revision changes in ABI may not be
+ * backward compatible.
+ *
+ * Response to a generic message with message type SCMI_MSG_VERSION
+ */
+struct scmi_msg_resp_prot_version {
+	__le16 minor_version;
+	__le16 major_version;
+};
+
+/**
+ * struct scmi_msg_hdr - Message(Tx/Rx) header
+ *
+ * @id: The identifier of the command being sent
+ * @protocol_id: The identifier of the protocol used to send @id command
+ * @seq: The token to identify the message. when a message/command returns,
+ *       the platform returns the whole message header unmodified including
+ *	 the token.
+ */
+struct scmi_msg_hdr {
+	u8 id;
+	u8 protocol_id;
+	u16 seq;
+	u32 status;
+	bool poll_completion;
+};
+
+/**
+ * struct scmi_msg - Message(Tx/Rx) structure
+ *
+ * @buf: Buffer pointer
+ * @len: Length of data in the Buffer
+ */
+struct scmi_msg {
+	void *buf;
+	size_t len;
+};
+
+/**
+ * struct scmi_xfer - Structure representing a message flow
+ *
+ * @hdr: Transmit message header
+ * @tx: Transmit message
+ * @rx: Receive message, the buffer should be pre-allocated to store
+ *	message. If request-ACK protocol is used, we can reuse the same
+ *	buffer for the rx path as we use for the tx path.
+ * @done: completion event
+ */
+
+struct scmi_xfer {
+	void *con_priv;
+	struct scmi_msg_hdr hdr;
+	struct scmi_msg tx;
+	struct scmi_msg rx;
+	struct completion done;
+};
+
+void scmi_one_xfer_put(const struct scmi_handle *h, struct scmi_xfer *xfer);
+int scmi_do_xfer(const struct scmi_handle *h, struct scmi_xfer *xfer);
+int scmi_one_xfer_init(const struct scmi_handle *h, u8 msg_id, u8 prot_id,
+		       size_t tx_size, size_t rx_size, struct scmi_xfer **p);
+int scmi_handle_put(const struct scmi_handle *handle);
+struct scmi_handle *scmi_handle_get(struct device *dev);
+void scmi_set_handle(struct scmi_device *scmi_dev);
+int scmi_version_get(const struct scmi_handle *h, u8 protocol, u32 *version);
+void scmi_setup_protocol_implemented(const struct scmi_handle *handle,
+				     u8 *prot_imp);
+
+int scmi_base_protocol_init(struct scmi_handle *h);
diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
new file mode 100644
index 000000000000..14b147135a0c
--- /dev/null
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -0,0 +1,871 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * System Control and Management Interface (SCMI) Message Protocol driver
+ *
+ * SCMI 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) 2018 ARM Ltd.
+ */
+
+#include <linux/bitmap.h>
+#include <linux/export.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/ktime.h>
+#include <linux/mailbox_client.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/processor.h>
+#include <linux/semaphore.h>
+#include <linux/slab.h>
+
+#include "common.h"
+
+#define MSG_ID_SHIFT		0
+#define MSG_ID_MASK		0xff
+#define MSG_TYPE_SHIFT		8
+#define MSG_TYPE_MASK		0x3
+#define MSG_PROTOCOL_ID_SHIFT	10
+#define MSG_PROTOCOL_ID_MASK	0xff
+#define MSG_TOKEN_ID_SHIFT	18
+#define MSG_TOKEN_ID_MASK	0x3ff
+#define MSG_XTRACT_TOKEN(header)	\
+	(((header) >> MSG_TOKEN_ID_SHIFT) & MSG_TOKEN_ID_MASK)
+
+enum scmi_error_codes {
+	SCMI_SUCCESS = 0,	/* Success */
+	SCMI_ERR_SUPPORT = -1,	/* Not supported */
+	SCMI_ERR_PARAMS = -2,	/* Invalid Parameters */
+	SCMI_ERR_ACCESS = -3,	/* Invalid access/permission denied */
+	SCMI_ERR_ENTRY = -4,	/* Not found */
+	SCMI_ERR_RANGE = -5,	/* Value out of range */
+	SCMI_ERR_BUSY = -6,	/* Device busy */
+	SCMI_ERR_COMMS = -7,	/* Communication Error */
+	SCMI_ERR_GENERIC = -8,	/* Generic Error */
+	SCMI_ERR_HARDWARE = -9,	/* Hardware Error */
+	SCMI_ERR_PROTOCOL = -10,/* Protocol Error */
+	SCMI_ERR_MAX
+};
+
+/* List of all  SCMI devices active in system */
+static LIST_HEAD(scmi_list);
+/* Protection for the entire list */
+static DEFINE_MUTEX(scmi_list_mutex);
+
+/**
+ * struct scmi_xfers_info - Structure to manage transfer information
+ *
+ * @xfer_block: Preallocated Message array
+ * @xfer_alloc_table: Bitmap table for allocated messages.
+ *	Index of this bitmap table is also used for message
+ *	sequence identifier.
+ * @xfer_lock: Protection for message allocation
+ */
+struct scmi_xfers_info {
+	struct scmi_xfer *xfer_block;
+	unsigned long *xfer_alloc_table;
+	/* protect transfer allocation */
+	spinlock_t xfer_lock;
+};
+
+/**
+ * struct scmi_desc - Description of SoC integration
+ *
+ * @max_rx_timeout_ms: Timeout for communication with SoC (in Milliseconds)
+ * @max_msg: Maximum number of messages that can be pending
+ *	simultaneously in the system
+ * @max_msg_size: Maximum size of data per message that can be handled.
+ */
+struct scmi_desc {
+	int max_rx_timeout_ms;
+	int max_msg;
+	int max_msg_size;
+};
+
+/**
+ * struct scmi_chan_info - Structure representing a SCMI channel informfation
+ *
+ * @cl: Mailbox Client
+ * @chan: Transmit/Receive mailbox channel
+ * @payload: Transmit/Receive mailbox channel payload area
+ * @dev: Reference to device in the SCMI hierarchy corresponding to this
+ *	 channel
+ */
+struct scmi_chan_info {
+	struct mbox_client cl;
+	struct mbox_chan *chan;
+	void __iomem *payload;
+	struct device *dev;
+	struct scmi_handle *handle;
+};
+
+/**
+ * struct scmi_info - Structure representing a  SCMI instance
+ *
+ * @dev: Device pointer
+ * @desc: SoC description for this instance
+ * @handle: Instance of SCMI handle to send to clients
+ * @version: SCMI revision information containing protocol version,
+ *	implementation version and (sub-)vendor identification.
+ * @minfo: Message info
+ * @tx_idr: IDR object to map protocol id to channel info pointer
+ * @protocols_imp: list of protocols implemented, currently maximum of
+ *	MAX_PROTOCOLS_IMP elements allocated by the base protocol
+ * @node: list head
+ * @users: Number of users of this instance
+ */
+struct scmi_info {
+	struct device *dev;
+	const struct scmi_desc *desc;
+	struct scmi_revision_info version;
+	struct scmi_handle handle;
+	struct scmi_xfers_info minfo;
+	struct idr tx_idr;
+	u8 *protocols_imp;
+	struct list_head node;
+	int users;
+};
+
+#define client_to_scmi_chan_info(c) container_of(c, struct scmi_chan_info, cl)
+#define handle_to_scmi_info(h)	container_of(h, struct scmi_info, handle)
+
+/*
+ * SCMI specification requires all parameters, message headers, return
+ * arguments or any protocol data to be expressed in little endian
+ * format only.
+ */
+struct scmi_shared_mem {
+	__le32 reserved;
+	__le32 channel_status;
+#define SCMI_SHMEM_CHAN_STAT_CHANNEL_ERROR	BIT(1)
+#define SCMI_SHMEM_CHAN_STAT_CHANNEL_FREE	BIT(0)
+	__le32 reserved1[2];
+	__le32 flags;
+#define SCMI_SHMEM_FLAG_INTR_ENABLED	BIT(0)
+	__le32 length;
+	__le32 msg_header;
+	u8 msg_payload[0];
+};
+
+static const int scmi_linux_errmap[] = {
+	/* better than switch case as long as return value is continuous */
+	0,			/* SCMI_SUCCESS */
+	-EOPNOTSUPP,		/* SCMI_ERR_SUPPORT */
+	-EINVAL,		/* SCMI_ERR_PARAM */
+	-EACCES,		/* SCMI_ERR_ACCESS */
+	-ENOENT,		/* SCMI_ERR_ENTRY */
+	-ERANGE,		/* SCMI_ERR_RANGE */
+	-EBUSY,			/* SCMI_ERR_BUSY */
+	-ECOMM,			/* SCMI_ERR_COMMS */
+	-EIO,			/* SCMI_ERR_GENERIC */
+	-EREMOTEIO,		/* SCMI_ERR_HARDWARE */
+	-EPROTO,		/* SCMI_ERR_PROTOCOL */
+};
+
+static inline int scmi_to_linux_errno(int errno)
+{
+	if (errno < SCMI_SUCCESS && errno > SCMI_ERR_MAX)
+		return scmi_linux_errmap[-errno];
+	return -EIO;
+}
+
+/**
+ * scmi_dump_header_dbg() - Helper to dump a message header.
+ *
+ * @dev: Device pointer corresponding to the SCMI entity
+ * @hdr: pointer to header.
+ */
+static inline void scmi_dump_header_dbg(struct device *dev,
+					struct scmi_msg_hdr *hdr)
+{
+	dev_dbg(dev, "Command ID: %x Sequence ID: %x Protocol: %x\n",
+		hdr->id, hdr->seq, hdr->protocol_id);
+}
+
+static void scmi_fetch_response(struct scmi_xfer *xfer,
+				struct scmi_shared_mem __iomem *mem)
+{
+	xfer->hdr.status = ioread32(mem->msg_payload);
+	/* Skip the length of header and statues in payload area i.e 8 bytes*/
+	xfer->rx.len = min_t(size_t, xfer->rx.len, ioread32(&mem->length) - 8);
+
+	/* Take a copy to the rx buffer.. */
+	memcpy_fromio(xfer->rx.buf, mem->msg_payload + 4, xfer->rx.len);
+}
+
+/**
+ * scmi_rx_callback() - mailbox client callback for receive messages
+ *
+ * @cl: client pointer
+ * @m: mailbox message
+ *
+ * Processes one received message to appropriate transfer information and
+ * signals completion of the transfer.
+ *
+ * NOTE: This function will be invoked in IRQ context, hence should be
+ * as optimal as possible.
+ */
+static void scmi_rx_callback(struct mbox_client *cl, void *m)
+{
+	u16 xfer_id;
+	struct scmi_xfer *xfer;
+	struct scmi_chan_info *cinfo = client_to_scmi_chan_info(cl);
+	struct device *dev = cinfo->dev;
+	struct scmi_info *info = handle_to_scmi_info(cinfo->handle);
+	struct scmi_xfers_info *minfo = &info->minfo;
+	struct scmi_shared_mem __iomem *mem = cinfo->payload;
+
+	xfer_id = MSG_XTRACT_TOKEN(ioread32(&mem->msg_header));
+
+	/*
+	 * Are we even expecting this?
+	 */
+	if (!test_bit(xfer_id, minfo->xfer_alloc_table)) {
+		dev_err(dev, "message for %d is not expected!\n", xfer_id);
+		return;
+	}
+
+	xfer = &minfo->xfer_block[xfer_id];
+
+	scmi_dump_header_dbg(dev, &xfer->hdr);
+	/* Is the message of valid length? */
+	if (xfer->rx.len > info->desc->max_msg_size) {
+		dev_err(dev, "unable to handle %zu xfer(max %d)\n",
+			xfer->rx.len, info->desc->max_msg_size);
+		return;
+	}
+
+	scmi_fetch_response(xfer, mem);
+	complete(&xfer->done);
+}
+
+/**
+ * pack_scmi_header() - packs and returns 32-bit header
+ *
+ * @hdr: pointer to header containing all the information on message id,
+ *	protocol id and sequence id.
+ */
+static inline u32 pack_scmi_header(struct scmi_msg_hdr *hdr)
+{
+	return ((hdr->id & MSG_ID_MASK) << MSG_ID_SHIFT) |
+	   ((hdr->seq & MSG_TOKEN_ID_MASK) << MSG_TOKEN_ID_SHIFT) |
+	   ((hdr->protocol_id & MSG_PROTOCOL_ID_MASK) << MSG_PROTOCOL_ID_SHIFT);
+}
+
+/**
+ * scmi_tx_prepare() - mailbox client callback to prepare for the transfer
+ *
+ * @cl: client pointer
+ * @m: mailbox message
+ *
+ * This function prepares the shared memory which contains the header and the
+ * payload.
+ */
+static void scmi_tx_prepare(struct mbox_client *cl, void *m)
+{
+	struct scmi_xfer *t = m;
+	struct scmi_chan_info *cinfo = client_to_scmi_chan_info(cl);
+	struct scmi_shared_mem __iomem *mem = cinfo->payload;
+
+	/* Mark channel busy + clear error */
+	iowrite32(0x0, &mem->channel_status);
+	iowrite32(t->hdr.poll_completion ? 0 : SCMI_SHMEM_FLAG_INTR_ENABLED,
+		  &mem->flags);
+	iowrite32(sizeof(mem->msg_header) + t->tx.len, &mem->length);
+	iowrite32(pack_scmi_header(&t->hdr), &mem->msg_header);
+	if (t->tx.buf)
+		memcpy_toio(mem->msg_payload, t->tx.buf, t->tx.len);
+}
+
+/**
+ * scmi_one_xfer_get() - Allocate one message
+ *
+ * @handle: SCMI entity handle
+ *
+ * Helper function which is used by various command functions that are
+ * exposed to clients of this driver for allocating a message traffic event.
+ *
+ * This function can sleep depending on pending requests already in the system
+ * for the SCMI entity. Further, this also holds a spinlock to maintain
+ * integrity of internal data structures.
+ *
+ * Return: 0 if all went fine, else corresponding error.
+ */
+static struct scmi_xfer *scmi_one_xfer_get(const struct scmi_handle *handle)
+{
+	u16 xfer_id;
+	struct scmi_xfer *xfer;
+	unsigned long flags, bit_pos;
+	struct scmi_info *info = handle_to_scmi_info(handle);
+	struct scmi_xfers_info *minfo = &info->minfo;
+
+	/* Keep the locked section as small as possible */
+	spin_lock_irqsave(&minfo->xfer_lock, flags);
+	bit_pos = find_first_zero_bit(minfo->xfer_alloc_table,
+				      info->desc->max_msg);
+	if (bit_pos == info->desc->max_msg) {
+		spin_unlock_irqrestore(&minfo->xfer_lock, flags);
+		return ERR_PTR(-ENOMEM);
+	}
+	set_bit(bit_pos, minfo->xfer_alloc_table);
+	spin_unlock_irqrestore(&minfo->xfer_lock, flags);
+
+	xfer_id = bit_pos;
+
+	xfer = &minfo->xfer_block[xfer_id];
+	xfer->hdr.seq = xfer_id;
+	reinit_completion(&xfer->done);
+
+	return xfer;
+}
+
+/**
+ * scmi_one_xfer_put() - Release a message
+ *
+ * @minfo: transfer info pointer
+ * @xfer: message that was reserved by scmi_one_xfer_get
+ *
+ * This holds a spinlock to maintain integrity of internal data structures.
+ */
+void scmi_one_xfer_put(const struct scmi_handle *handle, struct scmi_xfer *xfer)
+{
+	unsigned long flags;
+	struct scmi_info *info = handle_to_scmi_info(handle);
+	struct scmi_xfers_info *minfo = &info->minfo;
+
+	/*
+	 * Keep the locked section as small as possible
+	 * NOTE: we might escape with smp_mb and no lock here..
+	 * but just be conservative and symmetric.
+	 */
+	spin_lock_irqsave(&minfo->xfer_lock, flags);
+	clear_bit(xfer->hdr.seq, minfo->xfer_alloc_table);
+	spin_unlock_irqrestore(&minfo->xfer_lock, flags);
+}
+
+static bool
+scmi_xfer_poll_done(const struct scmi_chan_info *cinfo, struct scmi_xfer *xfer)
+{
+	struct scmi_shared_mem __iomem *mem = cinfo->payload;
+	u16 xfer_id = MSG_XTRACT_TOKEN(ioread32(&mem->msg_header));
+
+	if (xfer->hdr.seq != xfer_id)
+		return false;
+
+	return ioread32(&mem->channel_status) &
+		(SCMI_SHMEM_CHAN_STAT_CHANNEL_ERROR |
+		SCMI_SHMEM_CHAN_STAT_CHANNEL_FREE);
+}
+
+#define SCMI_MAX_POLL_TO_NS	(100 * NSEC_PER_USEC)
+
+static bool scmi_xfer_done_no_timeout(const struct scmi_chan_info *cinfo,
+				      struct scmi_xfer *xfer, ktime_t stop)
+{
+	ktime_t __cur = ktime_get();
+
+	return scmi_xfer_poll_done(cinfo, xfer) || ktime_after(__cur, stop);
+}
+
+/**
+ * scmi_do_xfer() - Do one transfer
+ *
+ * @info: Pointer to SCMI entity information
+ * @xfer: Transfer to initiate and wait for response
+ *
+ * Return: -ETIMEDOUT in case of no response, if transmit error,
+ *   return corresponding error, else if all goes well,
+ *   return 0.
+ */
+int scmi_do_xfer(const struct scmi_handle *handle, struct scmi_xfer *xfer)
+{
+	int ret;
+	int timeout;
+	struct scmi_info *info = handle_to_scmi_info(handle);
+	struct device *dev = info->dev;
+	struct scmi_chan_info *cinfo;
+
+	cinfo = idr_find(&info->tx_idr, xfer->hdr.protocol_id);
+	if (unlikely(!cinfo))
+		return -EINVAL;
+
+	ret = mbox_send_message(cinfo->chan, xfer);
+	if (ret < 0) {
+		dev_dbg(dev, "mbox send fail %d\n", ret);
+		return ret;
+	}
+
+	/* mbox_send_message returns non-negative value on success, so reset */
+	ret = 0;
+
+	if (xfer->hdr.poll_completion) {
+		ktime_t stop = ktime_add_ns(ktime_get(), SCMI_MAX_POLL_TO_NS);
+
+		spin_until_cond(scmi_xfer_done_no_timeout(cinfo, xfer, stop));
+
+		if (ktime_before(ktime_get(), stop))
+			scmi_fetch_response(xfer, cinfo->payload);
+		else
+			ret = -ETIMEDOUT;
+	} else {
+		/* And we wait for the response. */
+		timeout = msecs_to_jiffies(info->desc->max_rx_timeout_ms);
+		if (!wait_for_completion_timeout(&xfer->done, timeout)) {
+			dev_err(dev, "mbox timed out in resp(caller: %pS)\n",
+				(void *)_RET_IP_);
+			ret = -ETIMEDOUT;
+		}
+	}
+
+	if (!ret && xfer->hdr.status)
+		ret = scmi_to_linux_errno(xfer->hdr.status);
+
+	/*
+	 * NOTE: we might prefer not to need the mailbox ticker to manage the
+	 * transfer queueing since the protocol layer queues things by itself.
+	 * Unfortunately, we have to kick the mailbox framework after we have
+	 * received our message.
+	 */
+	mbox_client_txdone(cinfo->chan, ret);
+
+	return ret;
+}
+
+/**
+ * scmi_one_xfer_init() - Allocate and initialise one message
+ *
+ * @handle: SCMI entity handle
+ * @msg_id: Message identifier
+ * @msg_prot_id: Protocol identifier for the message
+ * @tx_size: transmit message size
+ * @rx_size: receive message size
+ * @p: pointer to the allocated and initialised message
+ *
+ * This function allocates the message using @scmi_one_xfer_get and
+ * initialise the header.
+ *
+ * Return: 0 if all went fine with @p pointing to message, else
+ *	corresponding error.
+ */
+int scmi_one_xfer_init(const struct scmi_handle *handle, u8 msg_id, u8 prot_id,
+		       size_t tx_size, size_t rx_size, struct scmi_xfer **p)
+{
+	int ret;
+	struct scmi_xfer *xfer;
+	struct scmi_info *info = handle_to_scmi_info(handle);
+	struct device *dev = info->dev;
+
+	/* Ensure we have sane transfer sizes */
+	if (rx_size > info->desc->max_msg_size ||
+	    tx_size > info->desc->max_msg_size)
+		return -ERANGE;
+
+	xfer = scmi_one_xfer_get(handle);
+	if (IS_ERR(xfer)) {
+		ret = PTR_ERR(xfer);
+		dev_err(dev, "failed to get free message slot(%d)\n", ret);
+		return ret;
+	}
+
+	xfer->tx.len = tx_size;
+	xfer->rx.len = rx_size ? : info->desc->max_msg_size;
+	xfer->hdr.id = msg_id;
+	xfer->hdr.protocol_id = prot_id;
+	xfer->hdr.poll_completion = false;
+
+	*p = xfer;
+	return 0;
+}
+
+/**
+ * scmi_version_get() - command to get the revision of the SCMI entity
+ *
+ * @handle: Handle to SCMI entity information
+ *
+ * Updates the SCMI information in the internal data structure.
+ *
+ * Return: 0 if all went fine, else return appropriate error.
+ */
+int scmi_version_get(const struct scmi_handle *handle, u8 protocol,
+		     u32 *version)
+{
+	int ret;
+	__le32 *rev_info;
+	struct scmi_xfer *t;
+
+	ret = scmi_one_xfer_init(handle, PROTOCOL_VERSION, protocol, 0,
+				 sizeof(*version), &t);
+	if (ret)
+		return ret;
+
+	ret = scmi_do_xfer(handle, t);
+	if (!ret) {
+		rev_info = t->rx.buf;
+		*version = le32_to_cpu(*rev_info);
+	}
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+void scmi_setup_protocol_implemented(const struct scmi_handle *handle,
+				     u8 *prot_imp)
+{
+	struct scmi_info *info = handle_to_scmi_info(handle);
+
+	info->protocols_imp = prot_imp;
+}
+
+static bool
+scmi_is_protocol_implemented(const struct scmi_handle *handle, u8 prot_id)
+{
+	int i;
+	struct scmi_info *info = handle_to_scmi_info(handle);
+
+	if (!info->protocols_imp)
+		return false;
+
+	for (i = 0; i < MAX_PROTOCOLS_IMP; i++)
+		if (info->protocols_imp[i] == prot_id)
+			return true;
+	return false;
+}
+
+/**
+ * scmi_handle_get() - Get the  SCMI handle for a device
+ *
+ * @dev: pointer to device for which we want SCMI handle
+ *
+ * NOTE: The function does not track individual clients of the framework
+ * and is expected to be maintained by caller of  SCMI protocol library.
+ * scmi_handle_put must be balanced with successful scmi_handle_get
+ *
+ * Return: pointer to handle if successful, NULL on error
+ */
+struct scmi_handle *scmi_handle_get(struct device *dev)
+{
+	struct list_head *p;
+	struct scmi_info *info;
+	struct scmi_handle *handle = NULL;
+
+	mutex_lock(&scmi_list_mutex);
+	list_for_each(p, &scmi_list) {
+		info = list_entry(p, struct scmi_info, node);
+		if (dev->parent == info->dev) {
+			handle = &info->handle;
+			info->users++;
+			break;
+		}
+	}
+	mutex_unlock(&scmi_list_mutex);
+
+	return handle;
+}
+
+/**
+ * scmi_handle_put() - Release the handle acquired by scmi_handle_get
+ *
+ * @handle: handle acquired by scmi_handle_get
+ *
+ * NOTE: The function does not track individual clients of the framework
+ * and is expected to be maintained by caller of  SCMI protocol library.
+ * scmi_handle_put must be balanced with successful scmi_handle_get
+ *
+ * Return: 0 is successfully released
+ *	if null was passed, it returns -EINVAL;
+ */
+int scmi_handle_put(const struct scmi_handle *handle)
+{
+	struct scmi_info *info;
+
+	if (!handle)
+		return -EINVAL;
+
+	info = handle_to_scmi_info(handle);
+	mutex_lock(&scmi_list_mutex);
+	if (!WARN_ON(!info->users))
+		info->users--;
+	mutex_unlock(&scmi_list_mutex);
+
+	return 0;
+}
+
+static const struct scmi_desc scmi_generic_desc = {
+	.max_rx_timeout_ms = 30,	/* we may increase this if required */
+	.max_msg = 20,		/* Limited by MBOX_TX_QUEUE_LEN */
+	.max_msg_size = 128,
+};
+
+/* Each compatible listed below must have descriptor associated with it */
+static const struct of_device_id scmi_of_match[] = {
+	{ .compatible = "arm,scmi", .data = &scmi_generic_desc },
+	{ /* Sentinel */ },
+};
+
+MODULE_DEVICE_TABLE(of, scmi_of_match);
+
+static int scmi_xfer_info_init(struct scmi_info *sinfo)
+{
+	int i;
+	struct scmi_xfer *xfer;
+	struct device *dev = sinfo->dev;
+	const struct scmi_desc *desc = sinfo->desc;
+	struct scmi_xfers_info *info = &sinfo->minfo;
+
+	/* Pre-allocated messages, no more than what hdr.seq can support */
+	if (WARN_ON(desc->max_msg >= (MSG_TOKEN_ID_MASK + 1))) {
+		dev_err(dev, "Maximum message of %d exceeds supported %d\n",
+			desc->max_msg, MSG_TOKEN_ID_MASK + 1);
+		return -EINVAL;
+	}
+
+	info->xfer_block = devm_kcalloc(dev, desc->max_msg,
+					sizeof(*info->xfer_block), GFP_KERNEL);
+	if (!info->xfer_block)
+		return -ENOMEM;
+
+	info->xfer_alloc_table = devm_kcalloc(dev, BITS_TO_LONGS(desc->max_msg),
+					      sizeof(long), GFP_KERNEL);
+	if (!info->xfer_alloc_table)
+		return -ENOMEM;
+
+	bitmap_zero(info->xfer_alloc_table, desc->max_msg);
+
+	/* Pre-initialize the buffer pointer to pre-allocated buffers */
+	for (i = 0, xfer = info->xfer_block; i < desc->max_msg; i++, xfer++) {
+		xfer->rx.buf = devm_kcalloc(dev, sizeof(u8), desc->max_msg_size,
+					    GFP_KERNEL);
+		if (!xfer->rx.buf)
+			return -ENOMEM;
+
+		xfer->tx.buf = xfer->rx.buf;
+		init_completion(&xfer->done);
+	}
+
+	spin_lock_init(&info->xfer_lock);
+
+	return 0;
+}
+
+static int scmi_mailbox_check(struct device_node *np)
+{
+	struct of_phandle_args arg;
+
+	return of_parse_phandle_with_args(np, "mboxes", "#mbox-cells", 0, &arg);
+}
+
+static int scmi_mbox_free_channel(int id, void *p, void *data)
+{
+	struct scmi_chan_info *cinfo = p;
+	struct idr *idr = data;
+
+	if (!IS_ERR_OR_NULL(cinfo->chan)) {
+		mbox_free_channel(cinfo->chan);
+		cinfo->chan = NULL;
+	}
+
+	idr_remove(idr, id);
+
+	return 0;
+}
+
+static int scmi_remove(struct platform_device *pdev)
+{
+	int ret = 0;
+	struct scmi_info *info = platform_get_drvdata(pdev);
+	struct idr *idr = &info->tx_idr;
+
+	mutex_lock(&scmi_list_mutex);
+	if (info->users)
+		ret = -EBUSY;
+	else
+		list_del(&info->node);
+	mutex_unlock(&scmi_list_mutex);
+
+	if (!ret) {
+		/* Safe to free channels since no more users */
+		ret = idr_for_each(idr, scmi_mbox_free_channel, idr);
+		idr_destroy(&info->tx_idr);
+	}
+
+	return ret;
+}
+
+static inline int
+scmi_mbox_chan_setup(struct scmi_info *info, struct device *dev, int prot_id)
+{
+	int ret;
+	struct resource res;
+	resource_size_t size;
+	struct device_node *shmem, *np = dev->of_node;
+	struct scmi_chan_info *cinfo;
+	struct mbox_client *cl;
+
+	if (scmi_mailbox_check(np)) {
+		cinfo = idr_find(&info->tx_idr, SCMI_PROTOCOL_BASE);
+		goto idr_alloc;
+	}
+
+	cinfo = devm_kzalloc(info->dev, sizeof(*cinfo), GFP_KERNEL);
+	if (!cinfo)
+		return -ENOMEM;
+
+	cinfo->dev = dev;
+
+	cl = &cinfo->cl;
+	cl->dev = dev;
+	cl->rx_callback = scmi_rx_callback;
+	cl->tx_prepare = scmi_tx_prepare;
+	cl->tx_block = false;
+	cl->knows_txdone = true;
+
+	shmem = of_parse_phandle(np, "shmem", 0);
+	ret = of_address_to_resource(shmem, 0, &res);
+	of_node_put(shmem);
+	if (ret) {
+		dev_err(dev, "failed to get SCMI Tx payload mem resource\n");
+		return ret;
+	}
+
+	size = resource_size(&res);
+	cinfo->payload = devm_ioremap(info->dev, res.start, size);
+	if (!cinfo->payload) {
+		dev_err(dev, "failed to ioremap SCMI Tx payload\n");
+		return -EADDRNOTAVAIL;
+	}
+
+	/* Transmit channel is first entry i.e. index 0 */
+	cinfo->chan = mbox_request_channel(cl, 0);
+	if (IS_ERR(cinfo->chan)) {
+		ret = PTR_ERR(cinfo->chan);
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "failed to request SCMI Tx mailbox\n");
+		return ret;
+	}
+
+idr_alloc:
+	ret = idr_alloc(&info->tx_idr, cinfo, prot_id, prot_id + 1, GFP_KERNEL);
+	if (ret != prot_id) {
+		dev_err(dev, "unable to allocate SCMI idr slot err %d\n", ret);
+		return ret;
+	}
+
+	cinfo->handle = &info->handle;
+	return 0;
+}
+
+static inline void
+scmi_create_protocol_device(struct device_node *np, struct scmi_info *info,
+			    int prot_id)
+{
+	struct scmi_device *sdev;
+
+	sdev = scmi_device_create(np, info->dev, prot_id);
+	if (!sdev) {
+		dev_err(info->dev, "failed to create %d protocol device\n",
+			prot_id);
+		return;
+	}
+
+	if (scmi_mbox_chan_setup(info, &sdev->dev, prot_id)) {
+		dev_err(&sdev->dev, "failed to setup transport\n");
+		scmi_device_destroy(sdev);
+	}
+
+	/* setup handle now as the transport is ready */
+	scmi_set_handle(sdev);
+}
+
+static int scmi_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct scmi_handle *handle;
+	const struct scmi_desc *desc;
+	struct scmi_info *info;
+	struct device *dev = &pdev->dev;
+	struct device_node *child, *np = dev->of_node;
+
+	/* Only mailbox method supported, check for the presence of one */
+	if (scmi_mailbox_check(np)) {
+		dev_err(dev, "no mailbox found in %pOF\n", np);
+		return -EINVAL;
+	}
+
+	desc = of_match_device(scmi_of_match, dev)->data;
+
+	info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+
+	info->dev = dev;
+	info->desc = desc;
+	INIT_LIST_HEAD(&info->node);
+
+	ret = scmi_xfer_info_init(info);
+	if (ret)
+		return ret;
+
+	platform_set_drvdata(pdev, info);
+	idr_init(&info->tx_idr);
+
+	handle = &info->handle;
+	handle->dev = info->dev;
+	handle->version = &info->version;
+
+	ret = scmi_mbox_chan_setup(info, dev, SCMI_PROTOCOL_BASE);
+	if (ret)
+		return ret;
+
+	ret = scmi_base_protocol_init(handle);
+	if (ret) {
+		dev_err(dev, "unable to communicate with SCMI(%d)\n", ret);
+		return ret;
+	}
+
+	mutex_lock(&scmi_list_mutex);
+	list_add_tail(&info->node, &scmi_list);
+	mutex_unlock(&scmi_list_mutex);
+
+	for_each_available_child_of_node(np, child) {
+		u32 prot_id;
+
+		if (of_property_read_u32(child, "reg", &prot_id))
+			continue;
+
+		prot_id &= MSG_PROTOCOL_ID_MASK;
+
+		if (!scmi_is_protocol_implemented(handle, prot_id)) {
+			dev_err(dev, "SCMI protocol %d not implemented\n",
+				prot_id);
+			continue;
+		}
+
+		scmi_create_protocol_device(child, info, prot_id);
+	}
+
+	return 0;
+}
+
+static struct platform_driver scmi_driver = {
+	.driver = {
+		   .name = "arm-scmi",
+		   .of_match_table = scmi_of_match,
+		   },
+	.probe = scmi_probe,
+	.remove = scmi_remove,
+};
+
+module_platform_driver(scmi_driver);
+
+MODULE_ALIAS("platform: arm-scmi");
+MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
+MODULE_DESCRIPTION("ARM SCMI protocol driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c
new file mode 100644
index 000000000000..987c64d19801
--- /dev/null
+++ b/drivers/firmware/arm_scmi/perf.c
@@ -0,0 +1,481 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * System Control and Management Interface (SCMI) Performance Protocol
+ *
+ * Copyright (C) 2018 ARM Ltd.
+ */
+
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+#include <linux/sort.h>
+
+#include "common.h"
+
+enum scmi_performance_protocol_cmd {
+	PERF_DOMAIN_ATTRIBUTES = 0x3,
+	PERF_DESCRIBE_LEVELS = 0x4,
+	PERF_LIMITS_SET = 0x5,
+	PERF_LIMITS_GET = 0x6,
+	PERF_LEVEL_SET = 0x7,
+	PERF_LEVEL_GET = 0x8,
+	PERF_NOTIFY_LIMITS = 0x9,
+	PERF_NOTIFY_LEVEL = 0xa,
+};
+
+struct scmi_opp {
+	u32 perf;
+	u32 power;
+	u32 trans_latency_us;
+};
+
+struct scmi_msg_resp_perf_attributes {
+	__le16 num_domains;
+	__le16 flags;
+#define POWER_SCALE_IN_MILLIWATT(x)	((x) & BIT(0))
+	__le32 stats_addr_low;
+	__le32 stats_addr_high;
+	__le32 stats_size;
+};
+
+struct scmi_msg_resp_perf_domain_attributes {
+	__le32 flags;
+#define SUPPORTS_SET_LIMITS(x)		((x) & BIT(31))
+#define SUPPORTS_SET_PERF_LVL(x)	((x) & BIT(30))
+#define SUPPORTS_PERF_LIMIT_NOTIFY(x)	((x) & BIT(29))
+#define SUPPORTS_PERF_LEVEL_NOTIFY(x)	((x) & BIT(28))
+	__le32 rate_limit_us;
+	__le32 sustained_freq_khz;
+	__le32 sustained_perf_level;
+	    u8 name[SCMI_MAX_STR_SIZE];
+};
+
+struct scmi_msg_perf_describe_levels {
+	__le32 domain;
+	__le32 level_index;
+};
+
+struct scmi_perf_set_limits {
+	__le32 domain;
+	__le32 max_level;
+	__le32 min_level;
+};
+
+struct scmi_perf_get_limits {
+	__le32 max_level;
+	__le32 min_level;
+};
+
+struct scmi_perf_set_level {
+	__le32 domain;
+	__le32 level;
+};
+
+struct scmi_perf_notify_level_or_limits {
+	__le32 domain;
+	__le32 notify_enable;
+};
+
+struct scmi_msg_resp_perf_describe_levels {
+	__le16 num_returned;
+	__le16 num_remaining;
+	struct {
+		__le32 perf_val;
+		__le32 power;
+		__le16 transition_latency_us;
+		__le16 reserved;
+	} opp[0];
+};
+
+struct perf_dom_info {
+	bool set_limits;
+	bool set_perf;
+	bool perf_limit_notify;
+	bool perf_level_notify;
+	u32 opp_count;
+	u32 sustained_freq_khz;
+	u32 sustained_perf_level;
+	u32 mult_factor;
+	char name[SCMI_MAX_STR_SIZE];
+	struct scmi_opp opp[MAX_OPPS];
+};
+
+struct scmi_perf_info {
+	int num_domains;
+	bool power_scale_mw;
+	u64 stats_addr;
+	u32 stats_size;
+	struct perf_dom_info *dom_info;
+};
+
+static int scmi_perf_attributes_get(const struct scmi_handle *handle,
+				    struct scmi_perf_info *pi)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_msg_resp_perf_attributes *attr;
+
+	ret = scmi_one_xfer_init(handle, PROTOCOL_ATTRIBUTES,
+				 SCMI_PROTOCOL_PERF, 0, sizeof(*attr), &t);
+	if (ret)
+		return ret;
+
+	attr = t->rx.buf;
+
+	ret = scmi_do_xfer(handle, t);
+	if (!ret) {
+		u16 flags = le16_to_cpu(attr->flags);
+
+		pi->num_domains = le16_to_cpu(attr->num_domains);
+		pi->power_scale_mw = POWER_SCALE_IN_MILLIWATT(flags);
+		pi->stats_addr = le32_to_cpu(attr->stats_addr_low) |
+				(u64)le32_to_cpu(attr->stats_addr_high) << 32;
+		pi->stats_size = le32_to_cpu(attr->stats_size);
+	}
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static int
+scmi_perf_domain_attributes_get(const struct scmi_handle *handle, u32 domain,
+				struct perf_dom_info *dom_info)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_msg_resp_perf_domain_attributes *attr;
+
+	ret = scmi_one_xfer_init(handle, PERF_DOMAIN_ATTRIBUTES,
+				 SCMI_PROTOCOL_PERF, sizeof(domain),
+				 sizeof(*attr), &t);
+	if (ret)
+		return ret;
+
+	*(__le32 *)t->tx.buf = cpu_to_le32(domain);
+	attr = t->rx.buf;
+
+	ret = scmi_do_xfer(handle, t);
+	if (!ret) {
+		u32 flags = le32_to_cpu(attr->flags);
+
+		dom_info->set_limits = SUPPORTS_SET_LIMITS(flags);
+		dom_info->set_perf = SUPPORTS_SET_PERF_LVL(flags);
+		dom_info->perf_limit_notify = SUPPORTS_PERF_LIMIT_NOTIFY(flags);
+		dom_info->perf_level_notify = SUPPORTS_PERF_LEVEL_NOTIFY(flags);
+		dom_info->sustained_freq_khz =
+					le32_to_cpu(attr->sustained_freq_khz);
+		dom_info->sustained_perf_level =
+					le32_to_cpu(attr->sustained_perf_level);
+		dom_info->mult_factor =	(dom_info->sustained_freq_khz * 1000) /
+					dom_info->sustained_perf_level;
+		memcpy(dom_info->name, attr->name, SCMI_MAX_STR_SIZE);
+	}
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static int opp_cmp_func(const void *opp1, const void *opp2)
+{
+	const struct scmi_opp *t1 = opp1, *t2 = opp2;
+
+	return t1->perf - t2->perf;
+}
+
+static int
+scmi_perf_describe_levels_get(const struct scmi_handle *handle, u32 domain,
+			      struct perf_dom_info *perf_dom)
+{
+	int ret, cnt;
+	u32 tot_opp_cnt = 0;
+	u16 num_returned, num_remaining;
+	struct scmi_xfer *t;
+	struct scmi_opp *opp;
+	struct scmi_msg_perf_describe_levels *dom_info;
+	struct scmi_msg_resp_perf_describe_levels *level_info;
+
+	ret = scmi_one_xfer_init(handle, PERF_DESCRIBE_LEVELS,
+				 SCMI_PROTOCOL_PERF, sizeof(*dom_info), 0, &t);
+	if (ret)
+		return ret;
+
+	dom_info = t->tx.buf;
+	level_info = t->rx.buf;
+
+	do {
+		dom_info->domain = cpu_to_le32(domain);
+		/* Set the number of OPPs to be skipped/already read */
+		dom_info->level_index = cpu_to_le32(tot_opp_cnt);
+
+		ret = scmi_do_xfer(handle, t);
+		if (ret)
+			break;
+
+		num_returned = le16_to_cpu(level_info->num_returned);
+		num_remaining = le16_to_cpu(level_info->num_remaining);
+		if (tot_opp_cnt + num_returned > MAX_OPPS) {
+			dev_err(handle->dev, "No. of OPPs exceeded MAX_OPPS");
+			break;
+		}
+
+		opp = &perf_dom->opp[tot_opp_cnt];
+		for (cnt = 0; cnt < num_returned; cnt++, opp++) {
+			opp->perf = le32_to_cpu(level_info->opp[cnt].perf_val);
+			opp->power = le32_to_cpu(level_info->opp[cnt].power);
+			opp->trans_latency_us = le16_to_cpu
+				(level_info->opp[cnt].transition_latency_us);
+
+			dev_dbg(handle->dev, "Level %d Power %d Latency %dus\n",
+				opp->perf, opp->power, opp->trans_latency_us);
+		}
+
+		tot_opp_cnt += num_returned;
+		/*
+		 * check for both returned and remaining to avoid infinite
+		 * loop due to buggy firmware
+		 */
+	} while (num_returned && num_remaining);
+
+	perf_dom->opp_count = tot_opp_cnt;
+	scmi_one_xfer_put(handle, t);
+
+	sort(perf_dom->opp, tot_opp_cnt, sizeof(*opp), opp_cmp_func, NULL);
+	return ret;
+}
+
+static int scmi_perf_limits_set(const struct scmi_handle *handle, u32 domain,
+				u32 max_perf, u32 min_perf)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_perf_set_limits *limits;
+
+	ret = scmi_one_xfer_init(handle, PERF_LIMITS_SET, SCMI_PROTOCOL_PERF,
+				 sizeof(*limits), 0, &t);
+	if (ret)
+		return ret;
+
+	limits = t->tx.buf;
+	limits->domain = cpu_to_le32(domain);
+	limits->max_level = cpu_to_le32(max_perf);
+	limits->min_level = cpu_to_le32(min_perf);
+
+	ret = scmi_do_xfer(handle, t);
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static int scmi_perf_limits_get(const struct scmi_handle *handle, u32 domain,
+				u32 *max_perf, u32 *min_perf)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_perf_get_limits *limits;
+
+	ret = scmi_one_xfer_init(handle, PERF_LIMITS_GET, SCMI_PROTOCOL_PERF,
+				 sizeof(__le32), 0, &t);
+	if (ret)
+		return ret;
+
+	*(__le32 *)t->tx.buf = cpu_to_le32(domain);
+
+	ret = scmi_do_xfer(handle, t);
+	if (!ret) {
+		limits = t->rx.buf;
+
+		*max_perf = le32_to_cpu(limits->max_level);
+		*min_perf = le32_to_cpu(limits->min_level);
+	}
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static int scmi_perf_level_set(const struct scmi_handle *handle, u32 domain,
+			       u32 level, bool poll)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_perf_set_level *lvl;
+
+	ret = scmi_one_xfer_init(handle, PERF_LEVEL_SET, SCMI_PROTOCOL_PERF,
+				 sizeof(*lvl), 0, &t);
+	if (ret)
+		return ret;
+
+	t->hdr.poll_completion = poll;
+	lvl = t->tx.buf;
+	lvl->domain = cpu_to_le32(domain);
+	lvl->level = cpu_to_le32(level);
+
+	ret = scmi_do_xfer(handle, t);
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static int scmi_perf_level_get(const struct scmi_handle *handle, u32 domain,
+			       u32 *level, bool poll)
+{
+	int ret;
+	struct scmi_xfer *t;
+
+	ret = scmi_one_xfer_init(handle, PERF_LEVEL_GET, SCMI_PROTOCOL_PERF,
+				 sizeof(u32), sizeof(u32), &t);
+	if (ret)
+		return ret;
+
+	t->hdr.poll_completion = poll;
+	*(__le32 *)t->tx.buf = cpu_to_le32(domain);
+
+	ret = scmi_do_xfer(handle, t);
+	if (!ret)
+		*level = le32_to_cpu(*(__le32 *)t->rx.buf);
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+/* Device specific ops */
+static int scmi_dev_domain_id(struct device *dev)
+{
+	struct of_phandle_args clkspec;
+
+	if (of_parse_phandle_with_args(dev->of_node, "clocks", "#clock-cells",
+				       0, &clkspec))
+		return -EINVAL;
+
+	return clkspec.args[0];
+}
+
+static int scmi_dvfs_add_opps_to_device(const struct scmi_handle *handle,
+					struct device *dev)
+{
+	int idx, ret, domain;
+	unsigned long freq;
+	struct scmi_opp *opp;
+	struct perf_dom_info *dom;
+	struct scmi_perf_info *pi = handle->perf_priv;
+
+	domain = scmi_dev_domain_id(dev);
+	if (domain < 0)
+		return domain;
+
+	dom = pi->dom_info + domain;
+	if (!dom)
+		return -EIO;
+
+	for (opp = dom->opp, idx = 0; idx < dom->opp_count; idx++, opp++) {
+		freq = opp->perf * dom->mult_factor;
+
+		ret = dev_pm_opp_add(dev, freq, 0);
+		if (ret) {
+			dev_warn(dev, "failed to add opp %luHz\n", freq);
+
+			while (idx-- > 0) {
+				freq = (--opp)->perf * dom->mult_factor;
+				dev_pm_opp_remove(dev, freq);
+			}
+			return ret;
+		}
+	}
+	return 0;
+}
+
+static int scmi_dvfs_get_transition_latency(const struct scmi_handle *handle,
+					    struct device *dev)
+{
+	struct perf_dom_info *dom;
+	struct scmi_perf_info *pi = handle->perf_priv;
+	int domain = scmi_dev_domain_id(dev);
+
+	if (domain < 0)
+		return domain;
+
+	dom = pi->dom_info + domain;
+	if (!dom)
+		return -EIO;
+
+	/* uS to nS */
+	return dom->opp[dom->opp_count - 1].trans_latency_us * 1000;
+}
+
+static int scmi_dvfs_freq_set(const struct scmi_handle *handle, u32 domain,
+			      unsigned long freq, bool poll)
+{
+	struct scmi_perf_info *pi = handle->perf_priv;
+	struct perf_dom_info *dom = pi->dom_info + domain;
+
+	return scmi_perf_level_set(handle, domain, freq / dom->mult_factor,
+				   poll);
+}
+
+static int scmi_dvfs_freq_get(const struct scmi_handle *handle, u32 domain,
+			      unsigned long *freq, bool poll)
+{
+	int ret;
+	u32 level;
+	struct scmi_perf_info *pi = handle->perf_priv;
+	struct perf_dom_info *dom = pi->dom_info + domain;
+
+	ret = scmi_perf_level_get(handle, domain, &level, poll);
+	if (!ret)
+		*freq = level * dom->mult_factor;
+
+	return ret;
+}
+
+static struct scmi_perf_ops perf_ops = {
+	.limits_set = scmi_perf_limits_set,
+	.limits_get = scmi_perf_limits_get,
+	.level_set = scmi_perf_level_set,
+	.level_get = scmi_perf_level_get,
+	.device_domain_id = scmi_dev_domain_id,
+	.get_transition_latency = scmi_dvfs_get_transition_latency,
+	.add_opps_to_device = scmi_dvfs_add_opps_to_device,
+	.freq_set = scmi_dvfs_freq_set,
+	.freq_get = scmi_dvfs_freq_get,
+};
+
+static int scmi_perf_protocol_init(struct scmi_handle *handle)
+{
+	int domain;
+	u32 version;
+	struct scmi_perf_info *pinfo;
+
+	scmi_version_get(handle, SCMI_PROTOCOL_PERF, &version);
+
+	dev_dbg(handle->dev, "Performance Version %d.%d\n",
+		PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
+
+	pinfo = devm_kzalloc(handle->dev, sizeof(*pinfo), GFP_KERNEL);
+	if (!pinfo)
+		return -ENOMEM;
+
+	scmi_perf_attributes_get(handle, pinfo);
+
+	pinfo->dom_info = devm_kcalloc(handle->dev, pinfo->num_domains,
+				       sizeof(*pinfo->dom_info), GFP_KERNEL);
+	if (!pinfo->dom_info)
+		return -ENOMEM;
+
+	for (domain = 0; domain < pinfo->num_domains; domain++) {
+		struct perf_dom_info *dom = pinfo->dom_info + domain;
+
+		scmi_perf_domain_attributes_get(handle, domain, dom);
+		scmi_perf_describe_levels_get(handle, domain, dom);
+	}
+
+	handle->perf_ops = &perf_ops;
+	handle->perf_priv = pinfo;
+
+	return 0;
+}
+
+static int __init scmi_perf_init(void)
+{
+	return scmi_protocol_register(SCMI_PROTOCOL_PERF,
+				      &scmi_perf_protocol_init);
+}
+subsys_initcall(scmi_perf_init);
diff --git a/drivers/firmware/arm_scmi/power.c b/drivers/firmware/arm_scmi/power.c
new file mode 100644
index 000000000000..087c2876cdf2
--- /dev/null
+++ b/drivers/firmware/arm_scmi/power.c
@@ -0,0 +1,221 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * System Control and Management Interface (SCMI) Power Protocol
+ *
+ * Copyright (C) 2018 ARM Ltd.
+ */
+
+#include "common.h"
+
+enum scmi_power_protocol_cmd {
+	POWER_DOMAIN_ATTRIBUTES = 0x3,
+	POWER_STATE_SET = 0x4,
+	POWER_STATE_GET = 0x5,
+	POWER_STATE_NOTIFY = 0x6,
+};
+
+struct scmi_msg_resp_power_attributes {
+	__le16 num_domains;
+	__le16 reserved;
+	__le32 stats_addr_low;
+	__le32 stats_addr_high;
+	__le32 stats_size;
+};
+
+struct scmi_msg_resp_power_domain_attributes {
+	__le32 flags;
+#define SUPPORTS_STATE_SET_NOTIFY(x)	((x) & BIT(31))
+#define SUPPORTS_STATE_SET_ASYNC(x)	((x) & BIT(30))
+#define SUPPORTS_STATE_SET_SYNC(x)	((x) & BIT(29))
+	    u8 name[SCMI_MAX_STR_SIZE];
+};
+
+struct scmi_power_set_state {
+	__le32 flags;
+#define STATE_SET_ASYNC		BIT(0)
+	__le32 domain;
+	__le32 state;
+};
+
+struct scmi_power_state_notify {
+	__le32 domain;
+	__le32 notify_enable;
+};
+
+struct power_dom_info {
+	bool state_set_sync;
+	bool state_set_async;
+	bool state_set_notify;
+	char name[SCMI_MAX_STR_SIZE];
+};
+
+struct scmi_power_info {
+	int num_domains;
+	u64 stats_addr;
+	u32 stats_size;
+	struct power_dom_info *dom_info;
+};
+
+static int scmi_power_attributes_get(const struct scmi_handle *handle,
+				     struct scmi_power_info *pi)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_msg_resp_power_attributes *attr;
+
+	ret = scmi_one_xfer_init(handle, PROTOCOL_ATTRIBUTES,
+				 SCMI_PROTOCOL_POWER, 0, sizeof(*attr), &t);
+	if (ret)
+		return ret;
+
+	attr = t->rx.buf;
+
+	ret = scmi_do_xfer(handle, t);
+	if (!ret) {
+		pi->num_domains = le16_to_cpu(attr->num_domains);
+		pi->stats_addr = le32_to_cpu(attr->stats_addr_low) |
+				(u64)le32_to_cpu(attr->stats_addr_high) << 32;
+		pi->stats_size = le32_to_cpu(attr->stats_size);
+	}
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static int
+scmi_power_domain_attributes_get(const struct scmi_handle *handle, u32 domain,
+				 struct power_dom_info *dom_info)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_msg_resp_power_domain_attributes *attr;
+
+	ret = scmi_one_xfer_init(handle, POWER_DOMAIN_ATTRIBUTES,
+				 SCMI_PROTOCOL_POWER, sizeof(domain),
+				 sizeof(*attr), &t);
+	if (ret)
+		return ret;
+
+	*(__le32 *)t->tx.buf = cpu_to_le32(domain);
+	attr = t->rx.buf;
+
+	ret = scmi_do_xfer(handle, t);
+	if (!ret) {
+		u32 flags = le32_to_cpu(attr->flags);
+
+		dom_info->state_set_notify = SUPPORTS_STATE_SET_NOTIFY(flags);
+		dom_info->state_set_async = SUPPORTS_STATE_SET_ASYNC(flags);
+		dom_info->state_set_sync = SUPPORTS_STATE_SET_SYNC(flags);
+		memcpy(dom_info->name, attr->name, SCMI_MAX_STR_SIZE);
+	}
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static int
+scmi_power_state_set(const struct scmi_handle *handle, u32 domain, u32 state)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_power_set_state *st;
+
+	ret = scmi_one_xfer_init(handle, POWER_STATE_SET, SCMI_PROTOCOL_POWER,
+				 sizeof(*st), 0, &t);
+	if (ret)
+		return ret;
+
+	st = t->tx.buf;
+	st->flags = cpu_to_le32(0);
+	st->domain = cpu_to_le32(domain);
+	st->state = cpu_to_le32(state);
+
+	ret = scmi_do_xfer(handle, t);
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static int
+scmi_power_state_get(const struct scmi_handle *handle, u32 domain, u32 *state)
+{
+	int ret;
+	struct scmi_xfer *t;
+
+	ret = scmi_one_xfer_init(handle, POWER_STATE_GET, SCMI_PROTOCOL_POWER,
+				 sizeof(u32), sizeof(u32), &t);
+	if (ret)
+		return ret;
+
+	*(__le32 *)t->tx.buf = cpu_to_le32(domain);
+
+	ret = scmi_do_xfer(handle, t);
+	if (!ret)
+		*state = le32_to_cpu(*(__le32 *)t->rx.buf);
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static int scmi_power_num_domains_get(const struct scmi_handle *handle)
+{
+	struct scmi_power_info *pi = handle->power_priv;
+
+	return pi->num_domains;
+}
+
+static char *scmi_power_name_get(const struct scmi_handle *handle, u32 domain)
+{
+	struct scmi_power_info *pi = handle->power_priv;
+	struct power_dom_info *dom = pi->dom_info + domain;
+
+	return dom->name;
+}
+
+static struct scmi_power_ops power_ops = {
+	.num_domains_get = scmi_power_num_domains_get,
+	.name_get = scmi_power_name_get,
+	.state_set = scmi_power_state_set,
+	.state_get = scmi_power_state_get,
+};
+
+static int scmi_power_protocol_init(struct scmi_handle *handle)
+{
+	int domain;
+	u32 version;
+	struct scmi_power_info *pinfo;
+
+	scmi_version_get(handle, SCMI_PROTOCOL_POWER, &version);
+
+	dev_dbg(handle->dev, "Power Version %d.%d\n",
+		PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
+
+	pinfo = devm_kzalloc(handle->dev, sizeof(*pinfo), GFP_KERNEL);
+	if (!pinfo)
+		return -ENOMEM;
+
+	scmi_power_attributes_get(handle, pinfo);
+
+	pinfo->dom_info = devm_kcalloc(handle->dev, pinfo->num_domains,
+				       sizeof(*pinfo->dom_info), GFP_KERNEL);
+	if (!pinfo->dom_info)
+		return -ENOMEM;
+
+	for (domain = 0; domain < pinfo->num_domains; domain++) {
+		struct power_dom_info *dom = pinfo->dom_info + domain;
+
+		scmi_power_domain_attributes_get(handle, domain, dom);
+	}
+
+	handle->power_ops = &power_ops;
+	handle->power_priv = pinfo;
+
+	return 0;
+}
+
+static int __init scmi_power_init(void)
+{
+	return scmi_protocol_register(SCMI_PROTOCOL_POWER,
+				      &scmi_power_protocol_init);
+}
+subsys_initcall(scmi_power_init);
diff --git a/drivers/firmware/arm_scmi/scmi_pm_domain.c b/drivers/firmware/arm_scmi/scmi_pm_domain.c
new file mode 100644
index 000000000000..87f737e01473
--- /dev/null
+++ b/drivers/firmware/arm_scmi/scmi_pm_domain.c
@@ -0,0 +1,129 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SCMI Generic power domain support.
+ *
+ * Copyright (C) 2018 ARM Ltd.
+ */
+
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/pm_domain.h>
+#include <linux/scmi_protocol.h>
+
+struct scmi_pm_domain {
+	struct generic_pm_domain genpd;
+	const struct scmi_handle *handle;
+	const char *name;
+	u32 domain;
+};
+
+#define to_scmi_pd(gpd) container_of(gpd, struct scmi_pm_domain, genpd)
+
+static int scmi_pd_power(struct generic_pm_domain *domain, bool power_on)
+{
+	int ret;
+	u32 state, ret_state;
+	struct scmi_pm_domain *pd = to_scmi_pd(domain);
+	const struct scmi_power_ops *ops = pd->handle->power_ops;
+
+	if (power_on)
+		state = SCMI_POWER_STATE_GENERIC_ON;
+	else
+		state = SCMI_POWER_STATE_GENERIC_OFF;
+
+	ret = ops->state_set(pd->handle, pd->domain, state);
+	if (!ret)
+		ret = ops->state_get(pd->handle, pd->domain, &ret_state);
+	if (!ret && state != ret_state)
+		return -EIO;
+
+	return ret;
+}
+
+static int scmi_pd_power_on(struct generic_pm_domain *domain)
+{
+	return scmi_pd_power(domain, true);
+}
+
+static int scmi_pd_power_off(struct generic_pm_domain *domain)
+{
+	return scmi_pd_power(domain, false);
+}
+
+static int scmi_pm_domain_probe(struct scmi_device *sdev)
+{
+	int num_domains, i;
+	struct device *dev = &sdev->dev;
+	struct device_node *np = dev->of_node;
+	struct scmi_pm_domain *scmi_pd;
+	struct genpd_onecell_data *scmi_pd_data;
+	struct generic_pm_domain **domains;
+	const struct scmi_handle *handle = sdev->handle;
+
+	if (!handle || !handle->power_ops)
+		return -ENODEV;
+
+	num_domains = handle->power_ops->num_domains_get(handle);
+	if (num_domains < 0) {
+		dev_err(dev, "number of domains not found\n");
+		return num_domains;
+	}
+
+	scmi_pd = devm_kcalloc(dev, num_domains, sizeof(*scmi_pd), GFP_KERNEL);
+	if (!scmi_pd)
+		return -ENOMEM;
+
+	scmi_pd_data = devm_kzalloc(dev, sizeof(*scmi_pd_data), GFP_KERNEL);
+	if (!scmi_pd_data)
+		return -ENOMEM;
+
+	domains = devm_kcalloc(dev, num_domains, sizeof(*domains), GFP_KERNEL);
+	if (!domains)
+		return -ENOMEM;
+
+	for (i = 0; i < num_domains; i++, scmi_pd++) {
+		u32 state;
+
+		domains[i] = &scmi_pd->genpd;
+
+		scmi_pd->domain = i;
+		scmi_pd->handle = handle;
+		scmi_pd->name = handle->power_ops->name_get(handle, i);
+		scmi_pd->genpd.name = scmi_pd->name;
+		scmi_pd->genpd.power_off = scmi_pd_power_off;
+		scmi_pd->genpd.power_on = scmi_pd_power_on;
+
+		if (handle->power_ops->state_get(handle, i, &state)) {
+			dev_warn(dev, "failed to get state for domain %d\n", i);
+			continue;
+		}
+
+		pm_genpd_init(&scmi_pd->genpd, NULL,
+			      state == SCMI_POWER_STATE_GENERIC_OFF);
+	}
+
+	scmi_pd_data->domains = domains;
+	scmi_pd_data->num_domains = num_domains;
+
+	of_genpd_add_provider_onecell(np, scmi_pd_data);
+
+	return 0;
+}
+
+static const struct scmi_device_id scmi_id_table[] = {
+	{ SCMI_PROTOCOL_POWER },
+	{ },
+};
+MODULE_DEVICE_TABLE(scmi, scmi_id_table);
+
+static struct scmi_driver scmi_power_domain_driver = {
+	.name = "scmi-power-domain",
+	.probe = scmi_pm_domain_probe,
+	.id_table = scmi_id_table,
+};
+module_scmi_driver(scmi_power_domain_driver);
+
+MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
+MODULE_DESCRIPTION("ARM SCMI power domain driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/firmware/arm_scmi/sensors.c b/drivers/firmware/arm_scmi/sensors.c
new file mode 100644
index 000000000000..bbb469fea0ed
--- /dev/null
+++ b/drivers/firmware/arm_scmi/sensors.c
@@ -0,0 +1,291 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * System Control and Management Interface (SCMI) Sensor Protocol
+ *
+ * Copyright (C) 2018 ARM Ltd.
+ */
+
+#include "common.h"
+
+enum scmi_sensor_protocol_cmd {
+	SENSOR_DESCRIPTION_GET = 0x3,
+	SENSOR_CONFIG_SET = 0x4,
+	SENSOR_TRIP_POINT_SET = 0x5,
+	SENSOR_READING_GET = 0x6,
+};
+
+struct scmi_msg_resp_sensor_attributes {
+	__le16 num_sensors;
+	u8 max_requests;
+	u8 reserved;
+	__le32 reg_addr_low;
+	__le32 reg_addr_high;
+	__le32 reg_size;
+};
+
+struct scmi_msg_resp_sensor_description {
+	__le16 num_returned;
+	__le16 num_remaining;
+	struct {
+		__le32 id;
+		__le32 attributes_low;
+#define SUPPORTS_ASYNC_READ(x)	((x) & BIT(31))
+#define NUM_TRIP_POINTS(x)	(((x) >> 4) & 0xff)
+		__le32 attributes_high;
+#define SENSOR_TYPE(x)		((x) & 0xff)
+#define SENSOR_SCALE(x)		(((x) >> 11) & 0x3f)
+#define SENSOR_UPDATE_SCALE(x)	(((x) >> 22) & 0x1f)
+#define SENSOR_UPDATE_BASE(x)	(((x) >> 27) & 0x1f)
+		    u8 name[SCMI_MAX_STR_SIZE];
+	} desc[0];
+};
+
+struct scmi_msg_set_sensor_config {
+	__le32 id;
+	__le32 event_control;
+};
+
+struct scmi_msg_set_sensor_trip_point {
+	__le32 id;
+	__le32 event_control;
+#define SENSOR_TP_EVENT_MASK	(0x3)
+#define SENSOR_TP_DISABLED	0x0
+#define SENSOR_TP_POSITIVE	0x1
+#define SENSOR_TP_NEGATIVE	0x2
+#define SENSOR_TP_BOTH		0x3
+#define SENSOR_TP_ID(x)		(((x) & 0xff) << 4)
+	__le32 value_low;
+	__le32 value_high;
+};
+
+struct scmi_msg_sensor_reading_get {
+	__le32 id;
+	__le32 flags;
+#define SENSOR_READ_ASYNC	BIT(0)
+};
+
+struct sensors_info {
+	int num_sensors;
+	int max_requests;
+	u64 reg_addr;
+	u32 reg_size;
+	struct scmi_sensor_info *sensors;
+};
+
+static int scmi_sensor_attributes_get(const struct scmi_handle *handle,
+				      struct sensors_info *si)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_msg_resp_sensor_attributes *attr;
+
+	ret = scmi_one_xfer_init(handle, PROTOCOL_ATTRIBUTES,
+				 SCMI_PROTOCOL_SENSOR, 0, sizeof(*attr), &t);
+	if (ret)
+		return ret;
+
+	attr = t->rx.buf;
+
+	ret = scmi_do_xfer(handle, t);
+	if (!ret) {
+		si->num_sensors = le16_to_cpu(attr->num_sensors);
+		si->max_requests = attr->max_requests;
+		si->reg_addr = le32_to_cpu(attr->reg_addr_low) |
+				(u64)le32_to_cpu(attr->reg_addr_high) << 32;
+		si->reg_size = le32_to_cpu(attr->reg_size);
+	}
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static int scmi_sensor_description_get(const struct scmi_handle *handle,
+				       struct sensors_info *si)
+{
+	int ret, cnt;
+	u32 desc_index = 0;
+	u16 num_returned, num_remaining;
+	struct scmi_xfer *t;
+	struct scmi_msg_resp_sensor_description *buf;
+
+	ret = scmi_one_xfer_init(handle, SENSOR_DESCRIPTION_GET,
+				 SCMI_PROTOCOL_SENSOR, sizeof(__le32), 0, &t);
+	if (ret)
+		return ret;
+
+	buf = t->rx.buf;
+
+	do {
+		/* Set the number of sensors to be skipped/already read */
+		*(__le32 *)t->tx.buf = cpu_to_le32(desc_index);
+
+		ret = scmi_do_xfer(handle, t);
+		if (ret)
+			break;
+
+		num_returned = le16_to_cpu(buf->num_returned);
+		num_remaining = le16_to_cpu(buf->num_remaining);
+
+		if (desc_index + num_returned > si->num_sensors) {
+			dev_err(handle->dev, "No. of sensors can't exceed %d",
+				si->num_sensors);
+			break;
+		}
+
+		for (cnt = 0; cnt < num_returned; cnt++) {
+			u32 attrh;
+			struct scmi_sensor_info *s;
+
+			attrh = le32_to_cpu(buf->desc[cnt].attributes_high);
+			s = &si->sensors[desc_index + cnt];
+			s->id = le32_to_cpu(buf->desc[cnt].id);
+			s->type = SENSOR_TYPE(attrh);
+			memcpy(s->name, buf->desc[cnt].name, SCMI_MAX_STR_SIZE);
+		}
+
+		desc_index += num_returned;
+		/*
+		 * check for both returned and remaining to avoid infinite
+		 * loop due to buggy firmware
+		 */
+	} while (num_returned && num_remaining);
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static int
+scmi_sensor_configuration_set(const struct scmi_handle *handle, u32 sensor_id)
+{
+	int ret;
+	u32 evt_cntl = BIT(0);
+	struct scmi_xfer *t;
+	struct scmi_msg_set_sensor_config *cfg;
+
+	ret = scmi_one_xfer_init(handle, SENSOR_CONFIG_SET,
+				 SCMI_PROTOCOL_SENSOR, sizeof(*cfg), 0, &t);
+	if (ret)
+		return ret;
+
+	cfg = t->tx.buf;
+	cfg->id = cpu_to_le32(sensor_id);
+	cfg->event_control = cpu_to_le32(evt_cntl);
+
+	ret = scmi_do_xfer(handle, t);
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static int scmi_sensor_trip_point_set(const struct scmi_handle *handle,
+				      u32 sensor_id, u8 trip_id, u64 trip_value)
+{
+	int ret;
+	u32 evt_cntl = SENSOR_TP_BOTH;
+	struct scmi_xfer *t;
+	struct scmi_msg_set_sensor_trip_point *trip;
+
+	ret = scmi_one_xfer_init(handle, SENSOR_TRIP_POINT_SET,
+				 SCMI_PROTOCOL_SENSOR, sizeof(*trip), 0, &t);
+	if (ret)
+		return ret;
+
+	trip = t->tx.buf;
+	trip->id = cpu_to_le32(sensor_id);
+	trip->event_control = cpu_to_le32(evt_cntl | SENSOR_TP_ID(trip_id));
+	trip->value_low = cpu_to_le32(trip_value & 0xffffffff);
+	trip->value_high = cpu_to_le32(trip_value >> 32);
+
+	ret = scmi_do_xfer(handle, t);
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static int scmi_sensor_reading_get(const struct scmi_handle *handle,
+				   u32 sensor_id, bool async, u64 *value)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_msg_sensor_reading_get *sensor;
+
+	ret = scmi_one_xfer_init(handle, SENSOR_READING_GET,
+				 SCMI_PROTOCOL_SENSOR, sizeof(*sensor),
+				 sizeof(u64), &t);
+	if (ret)
+		return ret;
+
+	sensor = t->tx.buf;
+	sensor->id = cpu_to_le32(sensor_id);
+	sensor->flags = cpu_to_le32(async ? SENSOR_READ_ASYNC : 0);
+
+	ret = scmi_do_xfer(handle, t);
+	if (!ret) {
+		__le32 *pval = t->rx.buf;
+
+		*value = le32_to_cpu(*pval);
+		*value |= (u64)le32_to_cpu(*(pval + 1)) << 32;
+	}
+
+	scmi_one_xfer_put(handle, t);
+	return ret;
+}
+
+static const struct scmi_sensor_info *
+scmi_sensor_info_get(const struct scmi_handle *handle, u32 sensor_id)
+{
+	struct sensors_info *si = handle->sensor_priv;
+
+	return si->sensors + sensor_id;
+}
+
+static int scmi_sensor_count_get(const struct scmi_handle *handle)
+{
+	struct sensors_info *si = handle->sensor_priv;
+
+	return si->num_sensors;
+}
+
+static struct scmi_sensor_ops sensor_ops = {
+	.count_get = scmi_sensor_count_get,
+	.info_get = scmi_sensor_info_get,
+	.configuration_set = scmi_sensor_configuration_set,
+	.trip_point_set = scmi_sensor_trip_point_set,
+	.reading_get = scmi_sensor_reading_get,
+};
+
+static int scmi_sensors_protocol_init(struct scmi_handle *handle)
+{
+	u32 version;
+	struct sensors_info *sinfo;
+
+	scmi_version_get(handle, SCMI_PROTOCOL_SENSOR, &version);
+
+	dev_dbg(handle->dev, "Sensor Version %d.%d\n",
+		PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
+
+	sinfo = devm_kzalloc(handle->dev, sizeof(*sinfo), GFP_KERNEL);
+	if (!sinfo)
+		return -ENOMEM;
+
+	scmi_sensor_attributes_get(handle, sinfo);
+
+	sinfo->sensors = devm_kcalloc(handle->dev, sinfo->num_sensors,
+				      sizeof(*sinfo->sensors), GFP_KERNEL);
+	if (!sinfo->sensors)
+		return -ENOMEM;
+
+	scmi_sensor_description_get(handle, sinfo);
+
+	handle->sensor_ops = &sensor_ops;
+	handle->sensor_priv = sinfo;
+
+	return 0;
+}
+
+static int __init scmi_sensors_init(void)
+{
+	return scmi_protocol_register(SCMI_PROTOCOL_SENSOR,
+				      &scmi_sensors_protocol_init);
+}
+subsys_initcall(scmi_sensors_init);
diff --git a/drivers/firmware/arm_scpi.c b/drivers/firmware/arm_scpi.c
index 7da9f1b83ebe..6d7a6c0a5e07 100644
--- a/drivers/firmware/arm_scpi.c
+++ b/drivers/firmware/arm_scpi.c
@@ -28,6 +28,7 @@
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/bitmap.h>
+#include <linux/bitfield.h>
 #include <linux/device.h>
 #include <linux/err.h>
 #include <linux/export.h>
@@ -45,48 +46,32 @@
 #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 CMD_LEGACY_DATA_SIZE_SHIFT	20
-#define CMD_LEGACY_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 PACK_LEGACY_SCPI_CMD(cmd_id, tx_sz)				\
-	((((cmd_id) & CMD_ID_MASK) << CMD_ID_SHIFT) |			       \
-	(((tx_sz) & CMD_LEGACY_DATA_SIZE_MASK) << CMD_LEGACY_DATA_SIZE_SHIFT))
-
-#define CMD_SIZE(cmd)	(((cmd) >> CMD_DATA_SIZE_SHIFT) & CMD_DATA_SIZE_MASK)
-#define CMD_LEGACY_SIZE(cmd)	(((cmd) >> CMD_LEGACY_DATA_SIZE_SHIFT) & \
-					CMD_LEGACY_DATA_SIZE_MASK)
-#define CMD_UNIQ_MASK	(CMD_TOKEN_ID_MASK << CMD_TOKEN_ID_SHIFT | CMD_ID_MASK)
+#define CMD_ID_MASK		GENMASK(6, 0)
+#define CMD_TOKEN_ID_MASK	GENMASK(15, 8)
+#define CMD_DATA_SIZE_MASK	GENMASK(24, 16)
+#define CMD_LEGACY_DATA_SIZE_MASK	GENMASK(28, 20)
+#define PACK_SCPI_CMD(cmd_id, tx_sz)		\
+	(FIELD_PREP(CMD_ID_MASK, cmd_id) |	\
+	FIELD_PREP(CMD_DATA_SIZE_MASK, tx_sz))
+#define PACK_LEGACY_SCPI_CMD(cmd_id, tx_sz)	\
+	(FIELD_PREP(CMD_ID_MASK, cmd_id) |	\
+	FIELD_PREP(CMD_LEGACY_DATA_SIZE_MASK, tx_sz))
+
+#define CMD_SIZE(cmd)	FIELD_GET(CMD_DATA_SIZE_MASK, cmd)
+#define CMD_UNIQ_MASK	(CMD_TOKEN_ID_MASK | 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		16
-#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 PROTO_REV_MAJOR_MASK	GENMASK(31, 16)
+#define PROTO_REV_MINOR_MASK	GENMASK(15, 0)
+
+#define FW_REV_MAJOR_MASK	GENMASK(31, 24)
+#define FW_REV_MINOR_MASK	GENMASK(23, 16)
+#define FW_REV_PATCH_MASK	GENMASK(15, 0)
 
 #define MAX_RX_TIMEOUT		(msecs_to_jiffies(30))
 
@@ -311,10 +296,6 @@ struct clk_get_info {
 	u8 name[20];
 } __packed;
 
-struct clk_get_value {
-	__le32 rate;
-} __packed;
-
 struct clk_set_value {
 	__le16 id;
 	__le16 reserved;
@@ -328,7 +309,9 @@ struct legacy_clk_set_value {
 } __packed;
 
 struct dvfs_info {
-	__le32 header;
+	u8 domain;
+	u8 opp_count;
+	__le16 latency;
 	struct {
 		__le32 freq;
 		__le32 m_volt;
@@ -340,10 +323,6 @@ struct dvfs_set {
 	u8 index;
 } __packed;
 
-struct sensor_capabilities {
-	__le16 sensors;
-} __packed;
-
 struct _scpi_sensor_info {
 	__le16 sensor_id;
 	u8 class;
@@ -351,11 +330,6 @@ struct _scpi_sensor_info {
 	char name[20];
 };
 
-struct sensor_value {
-	__le32 lo_val;
-	__le32 hi_val;
-} __packed;
-
 struct dev_pstate_set {
 	__le16 dev_id;
 	u8 pstate;
@@ -419,19 +393,20 @@ static void scpi_process_cmd(struct scpi_chan *ch, u32 cmd)
 		unsigned int len;
 
 		if (scpi_info->is_legacy) {
-			struct legacy_scpi_shared_mem *mem = ch->rx_payload;
+			struct legacy_scpi_shared_mem __iomem *mem =
+							ch->rx_payload;
 
 			/* RX Length is not replied by the legacy Firmware */
 			len = match->rx_len;
 
-			match->status = le32_to_cpu(mem->status);
+			match->status = ioread32(&mem->status);
 			memcpy_fromio(match->rx_buf, mem->payload, len);
 		} else {
-			struct scpi_shared_mem *mem = ch->rx_payload;
+			struct scpi_shared_mem __iomem *mem = ch->rx_payload;
 
-			len = min(match->rx_len, CMD_SIZE(cmd));
+			len = min_t(unsigned int, match->rx_len, CMD_SIZE(cmd));
 
-			match->status = le32_to_cpu(mem->status);
+			match->status = ioread32(&mem->status);
 			memcpy_fromio(match->rx_buf, mem->payload, len);
 		}
 
@@ -445,11 +420,11 @@ static void scpi_process_cmd(struct scpi_chan *ch, u32 cmd)
 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;
+	struct scpi_shared_mem __iomem *mem = ch->rx_payload;
 	u32 cmd = 0;
 
 	if (!scpi_info->is_legacy)
-		cmd = le32_to_cpu(mem->command);
+		cmd = ioread32(&mem->command);
 
 	scpi_process_cmd(ch, cmd);
 }
@@ -459,7 +434,7 @@ 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;
+	struct scpi_shared_mem __iomem *mem = ch->tx_payload;
 
 	if (t->tx_buf) {
 		if (scpi_info->is_legacy)
@@ -471,14 +446,14 @@ static void scpi_tx_prepare(struct mbox_client *c, void *msg)
 	if (t->rx_buf) {
 		if (!(++ch->token))
 			++ch->token;
-		ADD_SCPI_TOKEN(t->cmd, ch->token);
+		t->cmd |= FIELD_PREP(CMD_TOKEN_ID_MASK, ch->token);
 		spin_lock_irqsave(&ch->rx_lock, flags);
 		list_add_tail(&t->node, &ch->rx_pending);
 		spin_unlock_irqrestore(&ch->rx_lock, flags);
 	}
 
 	if (!scpi_info->is_legacy)
-		mem->command = cpu_to_le32(t->cmd);
+		iowrite32(t->cmd, &mem->command);
 }
 
 static struct scpi_xfer *get_scpi_xfer(struct scpi_chan *ch)
@@ -583,13 +558,13 @@ scpi_clk_get_range(u16 clk_id, unsigned long *min, unsigned long *max)
 static unsigned long scpi_clk_get_val(u16 clk_id)
 {
 	int ret;
-	struct clk_get_value clk;
+	__le32 rate;
 	__le16 le_clk_id = cpu_to_le16(clk_id);
 
 	ret = scpi_send_message(CMD_GET_CLOCK_VALUE, &le_clk_id,
-				sizeof(le_clk_id), &clk, sizeof(clk));
+				sizeof(le_clk_id), &rate, sizeof(rate));
 
-	return ret ? ret : le32_to_cpu(clk.rate);
+	return ret ? ret : le32_to_cpu(rate);
 }
 
 static int scpi_clk_set_val(u16 clk_id, unsigned long rate)
@@ -665,8 +640,8 @@ static struct scpi_dvfs_info *scpi_dvfs_get_info(u8 domain)
 	if (!info)
 		return ERR_PTR(-ENOMEM);
 
-	info->count = DVFS_OPP_COUNT(buf.header);
-	info->latency = DVFS_LATENCY(buf.header) * 1000; /* uS to nS */
+	info->count = buf.opp_count;
+	info->latency = le16_to_cpu(buf.latency) * 1000; /* uS to nS */
 
 	info->opps = kcalloc(info->count, sizeof(*opp), GFP_KERNEL);
 	if (!info->opps) {
@@ -713,9 +688,6 @@ static int scpi_dvfs_get_transition_latency(struct device *dev)
 	if (IS_ERR(info))
 		return PTR_ERR(info);
 
-	if (!info->latency)
-		return 0;
-
 	return info->latency;
 }
 
@@ -746,13 +718,13 @@ static int scpi_dvfs_add_opps_to_device(struct device *dev)
 
 static int scpi_sensor_get_capability(u16 *sensors)
 {
-	struct sensor_capabilities cap_buf;
+	__le16 cap;
 	int ret;
 
-	ret = scpi_send_message(CMD_SENSOR_CAPABILITIES, NULL, 0, &cap_buf,
-				sizeof(cap_buf));
+	ret = scpi_send_message(CMD_SENSOR_CAPABILITIES, NULL, 0, &cap,
+				sizeof(cap));
 	if (!ret)
-		*sensors = le16_to_cpu(cap_buf.sensors);
+		*sensors = le16_to_cpu(cap);
 
 	return ret;
 }
@@ -776,20 +748,19 @@ static int scpi_sensor_get_info(u16 sensor_id, struct scpi_sensor_info *info)
 static int scpi_sensor_get_value(u16 sensor, u64 *val)
 {
 	__le16 id = cpu_to_le16(sensor);
-	struct sensor_value buf;
+	__le64 value;
 	int ret;
 
 	ret = scpi_send_message(CMD_SENSOR_VALUE, &id, sizeof(id),
-				&buf, sizeof(buf));
+				&value, sizeof(value));
 	if (ret)
 		return ret;
 
 	if (scpi_info->is_legacy)
-		/* only 32-bits supported, hi_val can be junk */
-		*val = le32_to_cpu(buf.lo_val);
+		/* only 32-bits supported, upper 32 bits can be junk */
+		*val = le32_to_cpup((__le32 *)&value);
 	else
-		*val = (u64)le32_to_cpu(buf.hi_val) << 32 |
-			le32_to_cpu(buf.lo_val);
+		*val = le64_to_cpu(value);
 
 	return 0;
 }
@@ -864,9 +835,9 @@ static ssize_t protocol_version_show(struct device *dev,
 {
 	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));
+	return sprintf(buf, "%lu.%lu\n",
+		FIELD_GET(PROTO_REV_MAJOR_MASK, scpi_info->protocol_version),
+		FIELD_GET(PROTO_REV_MINOR_MASK, scpi_info->protocol_version));
 }
 static DEVICE_ATTR_RO(protocol_version);
 
@@ -875,10 +846,10 @@ static ssize_t firmware_version_show(struct device *dev,
 {
 	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));
+	return sprintf(buf, "%lu.%lu.%lu\n",
+		FIELD_GET(FW_REV_MAJOR_MASK, scpi_info->firmware_version),
+		FIELD_GET(FW_REV_MINOR_MASK, scpi_info->firmware_version),
+		FIELD_GET(FW_REV_PATCH_MASK, scpi_info->firmware_version));
 }
 static DEVICE_ATTR_RO(firmware_version);
 
@@ -889,37 +860,26 @@ static struct attribute *versions_attrs[] = {
 };
 ATTRIBUTE_GROUPS(versions);
 
-static void
-scpi_free_channels(struct device *dev, struct scpi_chan *pchan, int count)
+static void scpi_free_channels(void *data)
 {
+	struct scpi_drvinfo *info = data;
 	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);
-	}
+	for (i = 0; i < info->num_chans; i++)
+		mbox_free_channel(info->channels[i].chan);
 }
 
 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;
 }
@@ -952,7 +912,6 @@ 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;
 
@@ -969,13 +928,19 @@ static int scpi_probe(struct platform_device *pdev)
 		return -ENODEV;
 	}
 
-	scpi_chan = devm_kcalloc(dev, count, sizeof(*scpi_chan), GFP_KERNEL);
-	if (!scpi_chan)
+	scpi_info->channels = devm_kcalloc(dev, count, sizeof(struct scpi_chan),
+					   GFP_KERNEL);
+	if (!scpi_info->channels)
 		return -ENOMEM;
 
-	for (idx = 0; idx < count; idx++) {
+	ret = devm_add_action(dev, scpi_free_channels, scpi_info);
+	if (ret)
+		return ret;
+
+	for (; scpi_info->num_chans < count; scpi_info->num_chans++) {
 		resource_size_t size;
-		struct scpi_chan *pchan = scpi_chan + idx;
+		int idx = scpi_info->num_chans;
+		struct scpi_chan *pchan = scpi_info->channels + idx;
 		struct mbox_client *cl = &pchan->cl;
 		struct device_node *shmem = of_parse_phandle(np, "shmem", idx);
 
@@ -983,15 +948,14 @@ static int scpi_probe(struct platform_device *pdev)
 		of_node_put(shmem);
 		if (ret) {
 			dev_err(dev, "failed to get SCPI payload mem resource\n");
-			goto err;
+			return ret;
 		}
 
 		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;
+			return -EADDRNOTAVAIL;
 		}
 		pchan->tx_payload = pchan->rx_payload + (size >> 1);
 
@@ -1017,14 +981,9 @@ static int scpi_probe(struct platform_device *pdev)
 				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;
 	scpi_info->commands = scpi_std_commands;
 
 	platform_set_drvdata(pdev, scpi_info);
@@ -1043,23 +1002,31 @@ err:
 	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));
+	if (scpi_info->is_legacy && !scpi_info->protocol_version &&
+	    !scpi_info->firmware_version)
+		dev_info(dev, "SCP Protocol legacy pre-1.0 firmware\n");
+	else
+		dev_info(dev, "SCP Protocol %lu.%lu Firmware %lu.%lu.%lu version\n",
+			 FIELD_GET(PROTO_REV_MAJOR_MASK,
+				   scpi_info->protocol_version),
+			 FIELD_GET(PROTO_REV_MINOR_MASK,
+				   scpi_info->protocol_version),
+			 FIELD_GET(FW_REV_MAJOR_MASK,
+				   scpi_info->firmware_version),
+			 FIELD_GET(FW_REV_MINOR_MASK,
+				   scpi_info->firmware_version),
+			 FIELD_GET(FW_REV_PATCH_MASK,
+				   scpi_info->firmware_version));
 	scpi_info->scpi_ops = &scpi_ops;
 
-	ret = sysfs_create_groups(&dev->kobj, versions_groups);
+	ret = devm_device_add_groups(dev, versions_groups);
 	if (ret)
 		dev_err(dev, "unable to create sysfs version group\n");
 
-	return of_platform_populate(dev->of_node, NULL, NULL, dev);
+	return devm_of_platform_populate(dev);
 }
 
 static const struct of_device_id scpi_of_match[] = {
diff --git a/drivers/firmware/meson/meson_sm.c b/drivers/firmware/meson/meson_sm.c
index ff204421117b..0ec2ca87318c 100644
--- a/drivers/firmware/meson/meson_sm.c
+++ b/drivers/firmware/meson/meson_sm.c
@@ -17,8 +17,10 @@
 #include <linux/arm-smccc.h>
 #include <linux/bug.h>
 #include <linux/io.h>
+#include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
+#include <linux/platform_device.h>
 #include <linux/printk.h>
 #include <linux/types.h>
 #include <linux/sizes.h>
@@ -217,21 +219,11 @@ static const struct of_device_id meson_sm_ids[] = {
 	{ /* sentinel */ },
 };
 
-int __init meson_sm_init(void)
+static int __init meson_sm_probe(struct platform_device *pdev)
 {
 	const struct meson_sm_chip *chip;
-	const struct of_device_id *matched_np;
-	struct device_node *np;
 
-	np = of_find_matching_node_and_match(NULL, meson_sm_ids, &matched_np);
-	if (!np)
-		return -ENODEV;
-
-	chip = matched_np->data;
-	if (!chip) {
-		pr_err("unable to setup secure-monitor data\n");
-		goto out;
-	}
+	chip = of_match_device(meson_sm_ids, &pdev->dev)->data;
 
 	if (chip->cmd_shmem_in_base) {
 		fw.sm_shmem_in_base = meson_sm_map_shmem(chip->cmd_shmem_in_base,
@@ -257,4 +249,11 @@ out_in_base:
 out:
 	return -EINVAL;
 }
-device_initcall(meson_sm_init);
+
+static struct platform_driver meson_sm_driver = {
+	.driver = {
+		.name = "meson-sm",
+		.of_match_table = of_match_ptr(meson_sm_ids),
+	},
+};
+module_platform_driver_probe(meson_sm_driver, meson_sm_probe);
diff --git a/drivers/firmware/tegra/bpmp.c b/drivers/firmware/tegra/bpmp.c
index a7f461f2e650..14a456afa379 100644
--- a/drivers/firmware/tegra/bpmp.c
+++ b/drivers/firmware/tegra/bpmp.c
@@ -70,57 +70,20 @@ void tegra_bpmp_put(struct tegra_bpmp *bpmp)
 }
 EXPORT_SYMBOL_GPL(tegra_bpmp_put);
 
-static int tegra_bpmp_channel_get_index(struct tegra_bpmp_channel *channel)
-{
-	return channel - channel->bpmp->channels;
-}
-
 static int
 tegra_bpmp_channel_get_thread_index(struct tegra_bpmp_channel *channel)
 {
 	struct tegra_bpmp *bpmp = channel->bpmp;
-	unsigned int offset, count;
+	unsigned int count;
 	int index;
 
-	offset = bpmp->soc->channels.thread.offset;
 	count = bpmp->soc->channels.thread.count;
 
-	index = tegra_bpmp_channel_get_index(channel);
-	if (index < 0)
-		return index;
-
-	if (index < offset || index >= offset + count)
+	index = channel - channel->bpmp->threaded_channels;
+	if (index < 0 || index >= count)
 		return -EINVAL;
 
-	return index - offset;
-}
-
-static struct tegra_bpmp_channel *
-tegra_bpmp_channel_get_thread(struct tegra_bpmp *bpmp, unsigned int index)
-{
-	unsigned int offset = bpmp->soc->channels.thread.offset;
-	unsigned int count = bpmp->soc->channels.thread.count;
-
-	if (index >= count)
-		return NULL;
-
-	return &bpmp->channels[offset + index];
-}
-
-static struct tegra_bpmp_channel *
-tegra_bpmp_channel_get_tx(struct tegra_bpmp *bpmp)
-{
-	unsigned int offset = bpmp->soc->channels.cpu_tx.offset;
-
-	return &bpmp->channels[offset + smp_processor_id()];
-}
-
-static struct tegra_bpmp_channel *
-tegra_bpmp_channel_get_rx(struct tegra_bpmp *bpmp)
-{
-	unsigned int offset = bpmp->soc->channels.cpu_rx.offset;
-
-	return &bpmp->channels[offset];
+	return index;
 }
 
 static bool tegra_bpmp_message_valid(const struct tegra_bpmp_message *msg)
@@ -271,11 +234,7 @@ tegra_bpmp_write_threaded(struct tegra_bpmp *bpmp, unsigned int mrq,
 		goto unlock;
 	}
 
-	channel = tegra_bpmp_channel_get_thread(bpmp, index);
-	if (!channel) {
-		err = -EINVAL;
-		goto unlock;
-	}
+	channel = &bpmp->threaded_channels[index];
 
 	if (!tegra_bpmp_master_free(channel)) {
 		err = -EBUSY;
@@ -328,12 +287,18 @@ int tegra_bpmp_transfer_atomic(struct tegra_bpmp *bpmp,
 	if (!tegra_bpmp_message_valid(msg))
 		return -EINVAL;
 
-	channel = tegra_bpmp_channel_get_tx(bpmp);
+	channel = bpmp->tx_channel;
+
+	spin_lock(&bpmp->atomic_tx_lock);
 
 	err = tegra_bpmp_channel_write(channel, msg->mrq, MSG_ACK,
 				       msg->tx.data, msg->tx.size);
-	if (err < 0)
+	if (err < 0) {
+		spin_unlock(&bpmp->atomic_tx_lock);
 		return err;
+	}
+
+	spin_unlock(&bpmp->atomic_tx_lock);
 
 	err = mbox_send_message(bpmp->mbox.channel, NULL);
 	if (err < 0)
@@ -607,7 +572,7 @@ static void tegra_bpmp_handle_rx(struct mbox_client *client, void *data)
 	unsigned int i, count;
 	unsigned long *busy;
 
-	channel = tegra_bpmp_channel_get_rx(bpmp);
+	channel = bpmp->rx_channel;
 	count = bpmp->soc->channels.thread.count;
 	busy = bpmp->threaded.busy;
 
@@ -619,9 +584,7 @@ static void tegra_bpmp_handle_rx(struct mbox_client *client, void *data)
 	for_each_set_bit(i, busy, count) {
 		struct tegra_bpmp_channel *channel;
 
-		channel = tegra_bpmp_channel_get_thread(bpmp, i);
-		if (!channel)
-			continue;
+		channel = &bpmp->threaded_channels[i];
 
 		if (tegra_bpmp_master_acked(channel)) {
 			tegra_bpmp_channel_signal(channel);
@@ -698,7 +661,6 @@ static void tegra_bpmp_channel_cleanup(struct tegra_bpmp_channel *channel)
 
 static int tegra_bpmp_probe(struct platform_device *pdev)
 {
-	struct tegra_bpmp_channel *channel;
 	struct tegra_bpmp *bpmp;
 	unsigned int i;
 	char tag[32];
@@ -732,7 +694,7 @@ static int tegra_bpmp_probe(struct platform_device *pdev)
 	}
 
 	bpmp->rx.virt = gen_pool_dma_alloc(bpmp->rx.pool, 4096, &bpmp->rx.phys);
-	if (!bpmp->rx.pool) {
+	if (!bpmp->rx.virt) {
 		dev_err(&pdev->dev, "failed to allocate from RX pool\n");
 		err = -ENOMEM;
 		goto free_tx;
@@ -758,24 +720,45 @@ static int tegra_bpmp_probe(struct platform_device *pdev)
 		goto free_rx;
 	}
 
-	bpmp->num_channels = bpmp->soc->channels.cpu_tx.count +
-			     bpmp->soc->channels.thread.count +
-			     bpmp->soc->channels.cpu_rx.count;
+	spin_lock_init(&bpmp->atomic_tx_lock);
+	bpmp->tx_channel = devm_kzalloc(&pdev->dev, sizeof(*bpmp->tx_channel),
+					GFP_KERNEL);
+	if (!bpmp->tx_channel) {
+		err = -ENOMEM;
+		goto free_rx;
+	}
 
-	bpmp->channels = devm_kcalloc(&pdev->dev, bpmp->num_channels,
-				      sizeof(*channel), GFP_KERNEL);
-	if (!bpmp->channels) {
+	bpmp->rx_channel = devm_kzalloc(&pdev->dev, sizeof(*bpmp->rx_channel),
+	                                GFP_KERNEL);
+	if (!bpmp->rx_channel) {
 		err = -ENOMEM;
 		goto free_rx;
 	}
 
-	/* message channel initialization */
-	for (i = 0; i < bpmp->num_channels; i++) {
-		struct tegra_bpmp_channel *channel = &bpmp->channels[i];
+	bpmp->threaded_channels = devm_kcalloc(&pdev->dev, bpmp->threaded.count,
+					       sizeof(*bpmp->threaded_channels),
+					       GFP_KERNEL);
+	if (!bpmp->threaded_channels) {
+		err = -ENOMEM;
+		goto free_rx;
+	}
 
-		err = tegra_bpmp_channel_init(channel, bpmp, i);
+	err = tegra_bpmp_channel_init(bpmp->tx_channel, bpmp,
+				      bpmp->soc->channels.cpu_tx.offset);
+	if (err < 0)
+		goto free_rx;
+
+	err = tegra_bpmp_channel_init(bpmp->rx_channel, bpmp,
+				      bpmp->soc->channels.cpu_rx.offset);
+	if (err < 0)
+		goto cleanup_tx_channel;
+
+	for (i = 0; i < bpmp->threaded.count; i++) {
+		err = tegra_bpmp_channel_init(
+			&bpmp->threaded_channels[i], bpmp,
+			bpmp->soc->channels.thread.offset + i);
 		if (err < 0)
-			goto cleanup_channels;
+			goto cleanup_threaded_channels;
 	}
 
 	/* mbox registration */
@@ -788,15 +771,14 @@ static int tegra_bpmp_probe(struct platform_device *pdev)
 	if (IS_ERR(bpmp->mbox.channel)) {
 		err = PTR_ERR(bpmp->mbox.channel);
 		dev_err(&pdev->dev, "failed to get HSP mailbox: %d\n", err);
-		goto cleanup_channels;
+		goto cleanup_threaded_channels;
 	}
 
 	/* reset message channels */
-	for (i = 0; i < bpmp->num_channels; i++) {
-		struct tegra_bpmp_channel *channel = &bpmp->channels[i];
-
-		tegra_bpmp_channel_reset(channel);
-	}
+	tegra_bpmp_channel_reset(bpmp->tx_channel);
+	tegra_bpmp_channel_reset(bpmp->rx_channel);
+	for (i = 0; i < bpmp->threaded.count; i++)
+		tegra_bpmp_channel_reset(&bpmp->threaded_channels[i]);
 
 	err = tegra_bpmp_request_mrq(bpmp, MRQ_PING,
 				     tegra_bpmp_mrq_handle_ping, bpmp);
@@ -845,9 +827,15 @@ free_mrq:
 	tegra_bpmp_free_mrq(bpmp, MRQ_PING, bpmp);
 free_mbox:
 	mbox_free_channel(bpmp->mbox.channel);
-cleanup_channels:
-	while (i--)
-		tegra_bpmp_channel_cleanup(&bpmp->channels[i]);
+cleanup_threaded_channels:
+	for (i = 0; i < bpmp->threaded.count; i++) {
+		if (bpmp->threaded_channels[i].bpmp)
+			tegra_bpmp_channel_cleanup(&bpmp->threaded_channels[i]);
+	}
+
+	tegra_bpmp_channel_cleanup(bpmp->rx_channel);
+cleanup_tx_channel:
+	tegra_bpmp_channel_cleanup(bpmp->tx_channel);
 free_rx:
 	gen_pool_free(bpmp->rx.pool, (unsigned long)bpmp->rx.virt, 4096);
 free_tx:
@@ -858,18 +846,16 @@ free_tx:
 static const struct tegra_bpmp_soc tegra186_soc = {
 	.channels = {
 		.cpu_tx = {
-			.offset = 0,
-			.count = 6,
+			.offset = 3,
 			.timeout = 60 * USEC_PER_SEC,
 		},
 		.thread = {
-			.offset = 6,
-			.count = 7,
+			.offset = 0,
+			.count = 3,
 			.timeout = 600 * USEC_PER_SEC,
 		},
 		.cpu_rx = {
 			.offset = 13,
-			.count = 1,
 			.timeout = 0,
 		},
 	},