Merge tag 'arm-drivers-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc

Pull ARM SoC drivers from Arnd Bergmann:
 "The SoC driver updates contain changes to improve support for
  additional SoC variants, as well as cleanups an minor bugfixes
  in a number of existing drivers.

  Notable updates this time include:

   - Support for Qualcomm MSM8909 (Snapdragon 210) in various drivers

   - Updates for interconnect drivers on Qualcomm Snapdragon

   - A new driver support for NMI interrupts on Fujitsu A64fx

   - A rework of Broadcom BCMBCA Kconfig dependencies

   - Improved support for BCM2711 (Raspberry Pi 4) power management to
     allow the use of the V3D GPU

   - Cleanups to the NXP guts driver

   - Arm SCMI firmware driver updates to add tracing support, and use
     the firmware interfaces for system power control and for power
     capping"

* tag 'arm-drivers-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (125 commits)
  soc: a64fx-diag: disable modular build
  dt-bindings: soc: qcom: qcom,smd-rpm: add power-controller
  dt-bindings: soc: qcom: aoss: document qcom,sm8450-aoss-qmp
  dt-bindings: soc: qcom,rpmh-rsc: simplify qcom,tcs-config
  ARM: mach-qcom: Add support for MSM8909
  dt-bindings: arm: cpus: Document "qcom,msm8909-smp" enable-method
  soc: qcom: spm: Add CPU data for MSM8909
  dt-bindings: soc: qcom: spm: Add MSM8909 CPU compatible
  soc: qcom: rpmpd: Add compatible for MSM8909
  dt-bindings: power: qcom-rpmpd: Add MSM8909 power domains
  soc: qcom: smd-rpm: Add compatible for MSM8909
  dt-bindings: soc: qcom: smd-rpm: Add MSM8909
  soc: qcom: icc-bwmon: Remove unnecessary print function dev_err()
  soc: fujitsu: Add A64FX diagnostic interrupt driver
  soc: qcom: socinfo: Fix the id of SA8540P SoC
  soc: qcom: Make QCOM_RPMPD depend on PM
  tty: serial: bcm63xx: bcmbca: Replace ARCH_BCM_63XX with ARCH_BCMBCA
  spi: bcm63xx-hsspi: bcmbca: Replace ARCH_BCM_63XX with ARCH_BCMBCA
  clk: bcm: bcmbca: Replace ARCH_BCM_63XX with ARCH_BCMBCA
  hwrng: bcm2835: bcmbca: Replace ARCH_BCM_63XX with ARCH_BCMBCA
  ...

13 files changed, 1718 insertions, 223 deletions

diff --git a/drivers/firmware/arm_scmi/Kconfig b/drivers/firmware/arm_scmi/Kconfig
index 1e7b7fec97d9..a14f65444b35 100644
--- a/drivers/firmware/arm_scmi/Kconfig
+++ b/drivers/firmware/arm_scmi/Kconfig
@@ -149,4 +149,16 @@ config ARM_SCMI_POWER_DOMAIN
 	  will be called scmi_pm_domain. Note this may needed early in boot
 	  before rootfs may be available.
 
+config ARM_SCMI_POWER_CONTROL
+	tristate "SCMI system power control driver"
+	depends on ARM_SCMI_PROTOCOL || (COMPILE_TEST && OF)
+	help
+	  This enables System Power control logic which binds system shutdown or
+	  reboot actions to SCMI System Power notifications generated by SCP
+	  firmware.
+
+	  This driver can also be built as a module.  If so, the module will be
+	  called scmi_power_control. Note this may needed early in boot to catch
+	  early shutdown/reboot SCMI requests.
+
 endmenu
diff --git a/drivers/firmware/arm_scmi/Makefile b/drivers/firmware/arm_scmi/Makefile
index 8d4afadda38c..9ea86f8cc8f7 100644
--- a/drivers/firmware/arm_scmi/Makefile
+++ b/drivers/firmware/arm_scmi/Makefile
@@ -7,11 +7,12 @@ scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_SMC) += smc.o
 scmi-transport-$(CONFIG_ARM_SCMI_HAVE_MSG) += msg.o
 scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_VIRTIO) += virtio.o
 scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_OPTEE) += optee.o
-scmi-protocols-y = base.o clock.o perf.o power.o reset.o sensors.o system.o voltage.o
+scmi-protocols-y = base.o clock.o perf.o power.o reset.o sensors.o system.o voltage.o powercap.o
 scmi-module-objs := $(scmi-bus-y) $(scmi-driver-y) $(scmi-protocols-y) \
 		    $(scmi-transport-y)
 obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-module.o
 obj-$(CONFIG_ARM_SCMI_POWER_DOMAIN) += scmi_pm_domain.o
+obj-$(CONFIG_ARM_SCMI_POWER_CONTROL) += scmi_power_control.o
 
 ifeq ($(CONFIG_THUMB2_KERNEL)$(CONFIG_CC_IS_CLANG),yy)
 # The use of R7 in the SMCCC conflicts with the compiler's use of R7 as a frame
diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index 8b7ac6663d57..609ebedee9cb 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -19,6 +19,7 @@
 #include <linux/export.h>
 #include <linux/idr.h>
 #include <linux/io.h>
+#include <linux/io-64-nonatomic-hi-lo.h>
 #include <linux/kernel.h>
 #include <linux/ktime.h>
 #include <linux/hashtable.h>
@@ -60,6 +61,11 @@ static atomic_t transfer_last_id;
 static DEFINE_IDR(scmi_requested_devices);
 static DEFINE_MUTEX(scmi_requested_devices_mtx);
 
+/* Track globally the creation of SCMI SystemPower related devices */
+static bool scmi_syspower_registered;
+/* Protect access to scmi_syspower_registered */
+static DEFINE_MUTEX(scmi_syspower_mtx);
+
 struct scmi_requested_dev {
 	const struct scmi_device_id *id_table;
 	struct list_head node;
@@ -660,6 +666,11 @@ static void scmi_handle_notification(struct scmi_chan_info *cinfo,
 		smp_store_mb(xfer->priv, priv);
 	info->desc->ops->fetch_notification(cinfo, info->desc->max_msg_size,
 					    xfer);
+
+	trace_scmi_msg_dump(xfer->hdr.protocol_id, xfer->hdr.id, "NOTI",
+			    xfer->hdr.seq, xfer->hdr.status,
+			    xfer->rx.buf, xfer->rx.len);
+
 	scmi_notify(cinfo->handle, xfer->hdr.protocol_id,
 		    xfer->hdr.id, xfer->rx.buf, xfer->rx.len, ts);
 
@@ -694,6 +705,12 @@ static void scmi_handle_response(struct scmi_chan_info *cinfo,
 		smp_store_mb(xfer->priv, priv);
 	info->desc->ops->fetch_response(cinfo, xfer);
 
+	trace_scmi_msg_dump(xfer->hdr.protocol_id, xfer->hdr.id,
+			    xfer->hdr.type == MSG_TYPE_DELAYED_RESP ?
+			    "DLYD" : "RESP",
+			    xfer->hdr.seq, xfer->hdr.status,
+			    xfer->rx.buf, xfer->rx.len);
+
 	trace_scmi_rx_done(xfer->transfer_id, xfer->hdr.id,
 			   xfer->hdr.protocol_id, xfer->hdr.seq,
 			   xfer->hdr.type);
@@ -827,6 +844,12 @@ static int scmi_wait_for_message_response(struct scmi_chan_info *cinfo,
 				xfer->state = SCMI_XFER_RESP_OK;
 			}
 			spin_unlock_irqrestore(&xfer->lock, flags);
+
+			/* Trace polled replies. */
+			trace_scmi_msg_dump(xfer->hdr.protocol_id, xfer->hdr.id,
+					    "RESP",
+					    xfer->hdr.seq, xfer->hdr.status,
+					    xfer->rx.buf, xfer->rx.len);
 		}
 	} else {
 		/* And we wait for the response. */
@@ -903,6 +926,10 @@ static int do_xfer(const struct scmi_protocol_handle *ph,
 		return ret;
 	}
 
+	trace_scmi_msg_dump(xfer->hdr.protocol_id, xfer->hdr.id, "CMND",
+			    xfer->hdr.seq, xfer->hdr.status,
+			    xfer->tx.buf, xfer->tx.len);
+
 	ret = scmi_wait_for_message_response(cinfo, xfer);
 	if (!ret && xfer->hdr.status)
 		ret = scmi_to_linux_errno(xfer->hdr.status);
@@ -1259,10 +1286,174 @@ out:
 	return ret;
 }
 
+struct scmi_msg_get_fc_info {
+	__le32 domain;
+	__le32 message_id;
+};
+
+struct scmi_msg_resp_desc_fc {
+	__le32 attr;
+#define SUPPORTS_DOORBELL(x)		((x) & BIT(0))
+#define DOORBELL_REG_WIDTH(x)		FIELD_GET(GENMASK(2, 1), (x))
+	__le32 rate_limit;
+	__le32 chan_addr_low;
+	__le32 chan_addr_high;
+	__le32 chan_size;
+	__le32 db_addr_low;
+	__le32 db_addr_high;
+	__le32 db_set_lmask;
+	__le32 db_set_hmask;
+	__le32 db_preserve_lmask;
+	__le32 db_preserve_hmask;
+};
+
+static void
+scmi_common_fastchannel_init(const struct scmi_protocol_handle *ph,
+			     u8 describe_id, u32 message_id, u32 valid_size,
+			     u32 domain, void __iomem **p_addr,
+			     struct scmi_fc_db_info **p_db)
+{
+	int ret;
+	u32 flags;
+	u64 phys_addr;
+	u8 size;
+	void __iomem *addr;
+	struct scmi_xfer *t;
+	struct scmi_fc_db_info *db = NULL;
+	struct scmi_msg_get_fc_info *info;
+	struct scmi_msg_resp_desc_fc *resp;
+	const struct scmi_protocol_instance *pi = ph_to_pi(ph);
+
+	if (!p_addr) {
+		ret = -EINVAL;
+		goto err_out;
+	}
+
+	ret = ph->xops->xfer_get_init(ph, describe_id,
+				      sizeof(*info), sizeof(*resp), &t);
+	if (ret)
+		goto err_out;
+
+	info = t->tx.buf;
+	info->domain = cpu_to_le32(domain);
+	info->message_id = cpu_to_le32(message_id);
+
+	/*
+	 * Bail out on error leaving fc_info addresses zeroed; this includes
+	 * the case in which the requested domain/message_id does NOT support
+	 * fastchannels at all.
+	 */
+	ret = ph->xops->do_xfer(ph, t);
+	if (ret)
+		goto err_xfer;
+
+	resp = t->rx.buf;
+	flags = le32_to_cpu(resp->attr);
+	size = le32_to_cpu(resp->chan_size);
+	if (size != valid_size) {
+		ret = -EINVAL;
+		goto err_xfer;
+	}
+
+	phys_addr = le32_to_cpu(resp->chan_addr_low);
+	phys_addr |= (u64)le32_to_cpu(resp->chan_addr_high) << 32;
+	addr = devm_ioremap(ph->dev, phys_addr, size);
+	if (!addr) {
+		ret = -EADDRNOTAVAIL;
+		goto err_xfer;
+	}
+
+	*p_addr = addr;
+
+	if (p_db && SUPPORTS_DOORBELL(flags)) {
+		db = devm_kzalloc(ph->dev, sizeof(*db), GFP_KERNEL);
+		if (!db) {
+			ret = -ENOMEM;
+			goto err_db;
+		}
+
+		size = 1 << DOORBELL_REG_WIDTH(flags);
+		phys_addr = le32_to_cpu(resp->db_addr_low);
+		phys_addr |= (u64)le32_to_cpu(resp->db_addr_high) << 32;
+		addr = devm_ioremap(ph->dev, phys_addr, size);
+		if (!addr) {
+			ret = -EADDRNOTAVAIL;
+			goto err_db_mem;
+		}
+
+		db->addr = addr;
+		db->width = size;
+		db->set = le32_to_cpu(resp->db_set_lmask);
+		db->set |= (u64)le32_to_cpu(resp->db_set_hmask) << 32;
+		db->mask = le32_to_cpu(resp->db_preserve_lmask);
+		db->mask |= (u64)le32_to_cpu(resp->db_preserve_hmask) << 32;
+
+		*p_db = db;
+	}
+
+	ph->xops->xfer_put(ph, t);
+
+	dev_dbg(ph->dev,
+		"Using valid FC for protocol %X [MSG_ID:%u / RES_ID:%u]\n",
+		pi->proto->id, message_id, domain);
+
+	return;
+
+err_db_mem:
+	devm_kfree(ph->dev, db);
+
+err_db:
+	*p_addr = NULL;
+
+err_xfer:
+	ph->xops->xfer_put(ph, t);
+
+err_out:
+	dev_warn(ph->dev,
+		 "Failed to get FC for protocol %X [MSG_ID:%u / RES_ID:%u] - ret:%d. Using regular messaging.\n",
+		 pi->proto->id, message_id, domain, ret);
+}
+
+#define SCMI_PROTO_FC_RING_DB(w)			\
+do {							\
+	u##w val = 0;					\
+							\
+	if (db->mask)					\
+		val = ioread##w(db->addr) & db->mask;	\
+	iowrite##w((u##w)db->set | val, db->addr);	\
+} while (0)
+
+static void scmi_common_fastchannel_db_ring(struct scmi_fc_db_info *db)
+{
+	if (!db || !db->addr)
+		return;
+
+	if (db->width == 1)
+		SCMI_PROTO_FC_RING_DB(8);
+	else if (db->width == 2)
+		SCMI_PROTO_FC_RING_DB(16);
+	else if (db->width == 4)
+		SCMI_PROTO_FC_RING_DB(32);
+	else /* db->width == 8 */
+#ifdef CONFIG_64BIT
+		SCMI_PROTO_FC_RING_DB(64);
+#else
+	{
+		u64 val = 0;
+
+		if (db->mask)
+			val = ioread64_hi_lo(db->addr) & db->mask;
+		iowrite64_hi_lo(db->set | val, db->addr);
+	}
+#endif
+}
+
 static const struct scmi_proto_helpers_ops helpers_ops = {
 	.extended_name_get = scmi_common_extended_name_get,
 	.iter_response_init = scmi_iterator_init,
 	.iter_response_run = scmi_iterator_run,
+	.fastchannel_init = scmi_common_fastchannel_init,
+	.fastchannel_db_ring = scmi_common_fastchannel_db_ring,
 };
 
 /**
@@ -1497,6 +1688,30 @@ static void scmi_devm_release_protocol(struct device *dev, void *res)
 	scmi_protocol_release(dres->handle, dres->protocol_id);
 }
 
+static struct scmi_protocol_instance __must_check *
+scmi_devres_protocol_instance_get(struct scmi_device *sdev, u8 protocol_id)
+{
+	struct scmi_protocol_instance *pi;
+	struct scmi_protocol_devres *dres;
+
+	dres = devres_alloc(scmi_devm_release_protocol,
+			    sizeof(*dres), GFP_KERNEL);
+	if (!dres)
+		return ERR_PTR(-ENOMEM);
+
+	pi = scmi_get_protocol_instance(sdev->handle, protocol_id);
+	if (IS_ERR(pi)) {
+		devres_free(dres);
+		return pi;
+	}
+
+	dres->handle = sdev->handle;
+	dres->protocol_id = protocol_id;
+	devres_add(&sdev->dev, dres);
+
+	return pi;
+}
+
 /**
  * scmi_devm_protocol_get  - Devres managed get protocol operations and handle
  * @sdev: A reference to an scmi_device whose embedded struct device is to
@@ -1520,32 +1735,47 @@ scmi_devm_protocol_get(struct scmi_device *sdev, u8 protocol_id,
 		       struct scmi_protocol_handle **ph)
 {
 	struct scmi_protocol_instance *pi;
-	struct scmi_protocol_devres *dres;
-	struct scmi_handle *handle = sdev->handle;
 
 	if (!ph)
 		return ERR_PTR(-EINVAL);
 
-	dres = devres_alloc(scmi_devm_release_protocol,
-			    sizeof(*dres), GFP_KERNEL);
-	if (!dres)
-		return ERR_PTR(-ENOMEM);
-
-	pi = scmi_get_protocol_instance(handle, protocol_id);
-	if (IS_ERR(pi)) {
-		devres_free(dres);
+	pi = scmi_devres_protocol_instance_get(sdev, protocol_id);
+	if (IS_ERR(pi))
 		return pi;
-	}
-
-	dres->handle = handle;
-	dres->protocol_id = protocol_id;
-	devres_add(&sdev->dev, dres);
 
 	*ph = &pi->ph;
 
 	return pi->proto->ops;
 }
 
+/**
+ * scmi_devm_protocol_acquire  - Devres managed helper to get hold of a protocol
+ * @sdev: A reference to an scmi_device whose embedded struct device is to
+ *	  be used for devres accounting.
+ * @protocol_id: The protocol being requested.
+ *
+ * Get hold of a protocol accounting for its usage, possibly triggering its
+ * initialization but without getting access to its protocol specific operations
+ * and handle.
+ *
+ * Being a devres based managed method, protocol hold will be automatically
+ * released, and possibly de-initialized on last user, once the SCMI driver
+ * owning the scmi_device is unbound from it.
+ *
+ * Return: 0 on SUCCESS
+ */
+static int __must_check scmi_devm_protocol_acquire(struct scmi_device *sdev,
+						   u8 protocol_id)
+{
+	struct scmi_protocol_instance *pi;
+
+	pi = scmi_devres_protocol_instance_get(sdev, protocol_id);
+	if (IS_ERR(pi))
+		return PTR_ERR(pi);
+
+	return 0;
+}
+
 static int scmi_devm_protocol_match(struct device *dev, void *res, void *data)
 {
 	struct scmi_protocol_devres *dres = res;
@@ -1849,21 +2079,39 @@ scmi_get_protocol_device(struct device_node *np, struct scmi_info *info,
 	if (sdev)
 		return sdev;
 
+	mutex_lock(&scmi_syspower_mtx);
+	if (prot_id == SCMI_PROTOCOL_SYSTEM && scmi_syspower_registered) {
+		dev_warn(info->dev,
+			 "SCMI SystemPower protocol device must be unique !\n");
+		mutex_unlock(&scmi_syspower_mtx);
+
+		return NULL;
+	}
+
 	pr_debug("Creating SCMI device (%s) for protocol %x\n", name, prot_id);
 
 	sdev = scmi_device_create(np, info->dev, prot_id, name);
 	if (!sdev) {
 		dev_err(info->dev, "failed to create %d protocol device\n",
 			prot_id);
+		mutex_unlock(&scmi_syspower_mtx);
+
 		return NULL;
 	}
 
 	if (scmi_txrx_setup(info, &sdev->dev, prot_id)) {
 		dev_err(&sdev->dev, "failed to setup transport\n");
 		scmi_device_destroy(sdev);
+		mutex_unlock(&scmi_syspower_mtx);
+
 		return NULL;
 	}
 
+	if (prot_id == SCMI_PROTOCOL_SYSTEM)
+		scmi_syspower_registered = true;
+
+	mutex_unlock(&scmi_syspower_mtx);
+
 	return sdev;
 }
 
@@ -2132,6 +2380,7 @@ static int scmi_probe(struct platform_device *pdev)
 	handle = &info->handle;
 	handle->dev = info->dev;
 	handle->version = &info->version;
+	handle->devm_protocol_acquire = scmi_devm_protocol_acquire;
 	handle->devm_protocol_get = scmi_devm_protocol_get;
 	handle->devm_protocol_put = scmi_devm_protocol_put;
 
@@ -2401,6 +2650,7 @@ static int __init scmi_driver_init(void)
 	scmi_sensors_register();
 	scmi_voltage_register();
 	scmi_system_register();
+	scmi_powercap_register();
 
 	return platform_driver_register(&scmi_driver);
 }
@@ -2417,6 +2667,7 @@ static void __exit scmi_driver_exit(void)
 	scmi_sensors_unregister();
 	scmi_voltage_unregister();
 	scmi_system_unregister();
+	scmi_powercap_unregister();
 
 	scmi_bus_exit();
 
diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c
index bbb0331801ff..64ea2d2f2875 100644
--- a/drivers/firmware/arm_scmi/perf.c
+++ b/drivers/firmware/arm_scmi/perf.c
@@ -10,13 +10,14 @@
 #include <linux/bits.h>
 #include <linux/of.h>
 #include <linux/io.h>
-#include <linux/io-64-nonatomic-hi-lo.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/pm_opp.h>
 #include <linux/scmi_protocol.h>
 #include <linux/sort.h>
 
+#include <trace/events/scmi.h>
+
 #include "protocols.h"
 #include "notify.h"
 
@@ -35,6 +36,12 @@ enum scmi_performance_protocol_cmd {
 	PERF_DOMAIN_NAME_GET = 0xc,
 };
 
+enum {
+	PERF_FC_LEVEL,
+	PERF_FC_LIMIT,
+	PERF_FC_MAX,
+};
+
 struct scmi_opp {
 	u32 perf;
 	u32 power;
@@ -115,43 +122,6 @@ struct scmi_msg_resp_perf_describe_levels {
 	} opp[];
 };
 
-struct scmi_perf_get_fc_info {
-	__le32 domain;
-	__le32 message_id;
-};
-
-struct scmi_msg_resp_perf_desc_fc {
-	__le32 attr;
-#define SUPPORTS_DOORBELL(x)		((x) & BIT(0))
-#define DOORBELL_REG_WIDTH(x)		FIELD_GET(GENMASK(2, 1), (x))
-	__le32 rate_limit;
-	__le32 chan_addr_low;
-	__le32 chan_addr_high;
-	__le32 chan_size;
-	__le32 db_addr_low;
-	__le32 db_addr_high;
-	__le32 db_set_lmask;
-	__le32 db_set_hmask;
-	__le32 db_preserve_lmask;
-	__le32 db_preserve_hmask;
-};
-
-struct scmi_fc_db_info {
-	int width;
-	u64 set;
-	u64 mask;
-	void __iomem *addr;
-};
-
-struct scmi_fc_info {
-	void __iomem *level_set_addr;
-	void __iomem *limit_set_addr;
-	void __iomem *level_get_addr;
-	void __iomem *limit_get_addr;
-	struct scmi_fc_db_info *level_set_db;
-	struct scmi_fc_db_info *limit_set_db;
-};
-
 struct perf_dom_info {
 	bool set_limits;
 	bool set_perf;
@@ -360,40 +330,6 @@ scmi_perf_describe_levels_get(const struct scmi_protocol_handle *ph, u32 domain,
 	return ret;
 }
 
-#define SCMI_PERF_FC_RING_DB(w)				\
-do {							\
-	u##w val = 0;					\
-							\
-	if (db->mask)					\
-		val = ioread##w(db->addr) & db->mask;	\
-	iowrite##w((u##w)db->set | val, db->addr);	\
-} while (0)
-
-static void scmi_perf_fc_ring_db(struct scmi_fc_db_info *db)
-{
-	if (!db || !db->addr)
-		return;
-
-	if (db->width == 1)
-		SCMI_PERF_FC_RING_DB(8);
-	else if (db->width == 2)
-		SCMI_PERF_FC_RING_DB(16);
-	else if (db->width == 4)
-		SCMI_PERF_FC_RING_DB(32);
-	else /* db->width == 8 */
-#ifdef CONFIG_64BIT
-		SCMI_PERF_FC_RING_DB(64);
-#else
-	{
-		u64 val = 0;
-
-		if (db->mask)
-			val = ioread64_hi_lo(db->addr) & db->mask;
-		iowrite64_hi_lo(db->set | val, db->addr);
-	}
-#endif
-}
-
 static int scmi_perf_mb_limits_set(const struct scmi_protocol_handle *ph,
 				   u32 domain, u32 max_perf, u32 min_perf)
 {
@@ -426,10 +362,14 @@ static int scmi_perf_limits_set(const struct scmi_protocol_handle *ph,
 	if (PROTOCOL_REV_MAJOR(pi->version) >= 0x3 && !max_perf && !min_perf)
 		return -EINVAL;
 
-	if (dom->fc_info && dom->fc_info->limit_set_addr) {
-		iowrite32(max_perf, dom->fc_info->limit_set_addr);
-		iowrite32(min_perf, dom->fc_info->limit_set_addr + 4);
-		scmi_perf_fc_ring_db(dom->fc_info->limit_set_db);
+	if (dom->fc_info && dom->fc_info[PERF_FC_LIMIT].set_addr) {
+		struct scmi_fc_info *fci = &dom->fc_info[PERF_FC_LIMIT];
+
+		trace_scmi_fc_call(SCMI_PROTOCOL_PERF, PERF_LIMITS_SET,
+				   domain, min_perf, max_perf);
+		iowrite32(max_perf, fci->set_addr);
+		iowrite32(min_perf, fci->set_addr + 4);
+		ph->hops->fastchannel_db_ring(fci->set_db);
 		return 0;
 	}
 
@@ -468,9 +408,13 @@ static int scmi_perf_limits_get(const struct scmi_protocol_handle *ph,
 	struct scmi_perf_info *pi = ph->get_priv(ph);
 	struct perf_dom_info *dom = pi->dom_info + domain;
 
-	if (dom->fc_info && dom->fc_info->limit_get_addr) {
-		*max_perf = ioread32(dom->fc_info->limit_get_addr);
-		*min_perf = ioread32(dom->fc_info->limit_get_addr + 4);
+	if (dom->fc_info && dom->fc_info[PERF_FC_LIMIT].get_addr) {
+		struct scmi_fc_info *fci = &dom->fc_info[PERF_FC_LIMIT];
+
+		*max_perf = ioread32(fci->get_addr);
+		*min_perf = ioread32(fci->get_addr + 4);
+		trace_scmi_fc_call(SCMI_PROTOCOL_PERF, PERF_LIMITS_GET,
+				   domain, *min_perf, *max_perf);
 		return 0;
 	}
 
@@ -505,9 +449,13 @@ static int scmi_perf_level_set(const struct scmi_protocol_handle *ph,
 	struct scmi_perf_info *pi = ph->get_priv(ph);
 	struct perf_dom_info *dom = pi->dom_info + domain;
 
-	if (dom->fc_info && dom->fc_info->level_set_addr) {
-		iowrite32(level, dom->fc_info->level_set_addr);
-		scmi_perf_fc_ring_db(dom->fc_info->level_set_db);
+	if (dom->fc_info && dom->fc_info[PERF_FC_LEVEL].set_addr) {
+		struct scmi_fc_info *fci = &dom->fc_info[PERF_FC_LEVEL];
+
+		trace_scmi_fc_call(SCMI_PROTOCOL_PERF, PERF_LEVEL_SET,
+				   domain, level, 0);
+		iowrite32(level, fci->set_addr);
+		ph->hops->fastchannel_db_ring(fci->set_db);
 		return 0;
 	}
 
@@ -542,8 +490,10 @@ static int scmi_perf_level_get(const struct scmi_protocol_handle *ph,
 	struct scmi_perf_info *pi = ph->get_priv(ph);
 	struct perf_dom_info *dom = pi->dom_info + domain;
 
-	if (dom->fc_info && dom->fc_info->level_get_addr) {
-		*level = ioread32(dom->fc_info->level_get_addr);
+	if (dom->fc_info && dom->fc_info[PERF_FC_LEVEL].get_addr) {
+		*level = ioread32(dom->fc_info[PERF_FC_LEVEL].get_addr);
+		trace_scmi_fc_call(SCMI_PROTOCOL_PERF, PERF_LEVEL_GET,
+				   domain, *level, 0);
 		return 0;
 	}
 
@@ -572,100 +522,33 @@ static int scmi_perf_level_limits_notify(const struct scmi_protocol_handle *ph,
 	return ret;
 }
 
-static bool scmi_perf_fc_size_is_valid(u32 msg, u32 size)
-{
-	if ((msg == PERF_LEVEL_GET || msg == PERF_LEVEL_SET) && size == 4)
-		return true;
-	if ((msg == PERF_LIMITS_GET || msg == PERF_LIMITS_SET) && size == 8)
-		return true;
-	return false;
-}
-
-static void
-scmi_perf_domain_desc_fc(const struct scmi_protocol_handle *ph, u32 domain,
-			 u32 message_id, void __iomem **p_addr,
-			 struct scmi_fc_db_info **p_db)
-{
-	int ret;
-	u32 flags;
-	u64 phys_addr;
-	u8 size;
-	void __iomem *addr;
-	struct scmi_xfer *t;
-	struct scmi_fc_db_info *db;
-	struct scmi_perf_get_fc_info *info;
-	struct scmi_msg_resp_perf_desc_fc *resp;
-
-	if (!p_addr)
-		return;
-
-	ret = ph->xops->xfer_get_init(ph, PERF_DESCRIBE_FASTCHANNEL,
-				      sizeof(*info), sizeof(*resp), &t);
-	if (ret)
-		return;
-
-	info = t->tx.buf;
-	info->domain = cpu_to_le32(domain);
-	info->message_id = cpu_to_le32(message_id);
-
-	ret = ph->xops->do_xfer(ph, t);
-	if (ret)
-		goto err_xfer;
-
-	resp = t->rx.buf;
-	flags = le32_to_cpu(resp->attr);
-	size = le32_to_cpu(resp->chan_size);
-	if (!scmi_perf_fc_size_is_valid(message_id, size))
-		goto err_xfer;
-
-	phys_addr = le32_to_cpu(resp->chan_addr_low);
-	phys_addr |= (u64)le32_to_cpu(resp->chan_addr_high) << 32;
-	addr = devm_ioremap(ph->dev, phys_addr, size);
-	if (!addr)
-		goto err_xfer;
-	*p_addr = addr;
-
-	if (p_db && SUPPORTS_DOORBELL(flags)) {
-		db = devm_kzalloc(ph->dev, sizeof(*db), GFP_KERNEL);
-		if (!db)
-			goto err_xfer;
-
-		size = 1 << DOORBELL_REG_WIDTH(flags);
-		phys_addr = le32_to_cpu(resp->db_addr_low);
-		phys_addr |= (u64)le32_to_cpu(resp->db_addr_high) << 32;
-		addr = devm_ioremap(ph->dev, phys_addr, size);
-		if (!addr)
-			goto err_xfer;
-
-		db->addr = addr;
-		db->width = size;
-		db->set = le32_to_cpu(resp->db_set_lmask);
-		db->set |= (u64)le32_to_cpu(resp->db_set_hmask) << 32;
-		db->mask = le32_to_cpu(resp->db_preserve_lmask);
-		db->mask |= (u64)le32_to_cpu(resp->db_preserve_hmask) << 32;
-		*p_db = db;
-	}
-err_xfer:
-	ph->xops->xfer_put(ph, t);
-}
-
 static void scmi_perf_domain_init_fc(const struct scmi_protocol_handle *ph,
 				     u32 domain, struct scmi_fc_info **p_fc)
 {
 	struct scmi_fc_info *fc;
 
-	fc = devm_kzalloc(ph->dev, sizeof(*fc), GFP_KERNEL);
+	fc = devm_kcalloc(ph->dev, PERF_FC_MAX, sizeof(*fc), GFP_KERNEL);
 	if (!fc)
 		return;
 
-	scmi_perf_domain_desc_fc(ph, domain, PERF_LEVEL_SET,
-				 &fc->level_set_addr, &fc->level_set_db);
-	scmi_perf_domain_desc_fc(ph, domain, PERF_LEVEL_GET,
-				 &fc->level_get_addr, NULL);
-	scmi_perf_domain_desc_fc(ph, domain, PERF_LIMITS_SET,
-				 &fc->limit_set_addr, &fc->limit_set_db);
-	scmi_perf_domain_desc_fc(ph, domain, PERF_LIMITS_GET,
-				 &fc->limit_get_addr, NULL);
+	ph->hops->fastchannel_init(ph, PERF_DESCRIBE_FASTCHANNEL,
+				   PERF_LEVEL_SET, 4, domain,
+				   &fc[PERF_FC_LEVEL].set_addr,
+				   &fc[PERF_FC_LEVEL].set_db);
+
+	ph->hops->fastchannel_init(ph, PERF_DESCRIBE_FASTCHANNEL,
+				   PERF_LEVEL_GET, 4, domain,
+				   &fc[PERF_FC_LEVEL].get_addr, NULL);
+
+	ph->hops->fastchannel_init(ph, PERF_DESCRIBE_FASTCHANNEL,
+				   PERF_LIMITS_SET, 8, domain,
+				   &fc[PERF_FC_LIMIT].set_addr,
+				   &fc[PERF_FC_LIMIT].set_db);
+
+	ph->hops->fastchannel_init(ph, PERF_DESCRIBE_FASTCHANNEL,
+				   PERF_LIMITS_GET, 8, domain,
+				   &fc[PERF_FC_LIMIT].get_addr, NULL);
+
 	*p_fc = fc;
 }
 
@@ -789,7 +672,7 @@ static bool scmi_fast_switch_possible(const struct scmi_protocol_handle *ph,
 
 	dom = pi->dom_info + scmi_dev_domain_id(dev);
 
-	return dom->fc_info && dom->fc_info->level_set_addr;
+	return dom->fc_info && dom->fc_info[PERF_FC_LEVEL].set_addr;
 }
 
 static bool scmi_power_scale_mw_get(const struct scmi_protocol_handle *ph)
diff --git a/drivers/firmware/arm_scmi/powercap.c b/drivers/firmware/arm_scmi/powercap.c
new file mode 100644
index 000000000000..83b90bde755c
--- /dev/null
+++ b/drivers/firmware/arm_scmi/powercap.c
@@ -0,0 +1,866 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * System Control and Management Interface (SCMI) Powercap Protocol
+ *
+ * Copyright (C) 2022 ARM Ltd.
+ */
+
+#define pr_fmt(fmt) "SCMI Notifications POWERCAP - " fmt
+
+#include <linux/bitfield.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/scmi_protocol.h>
+
+#include <trace/events/scmi.h>
+
+#include "protocols.h"
+#include "notify.h"
+
+enum scmi_powercap_protocol_cmd {
+	POWERCAP_DOMAIN_ATTRIBUTES = 0x3,
+	POWERCAP_CAP_GET = 0x4,
+	POWERCAP_CAP_SET = 0x5,
+	POWERCAP_PAI_GET = 0x6,
+	POWERCAP_PAI_SET = 0x7,
+	POWERCAP_DOMAIN_NAME_GET = 0x8,
+	POWERCAP_MEASUREMENTS_GET = 0x9,
+	POWERCAP_CAP_NOTIFY = 0xa,
+	POWERCAP_MEASUREMENTS_NOTIFY = 0xb,
+	POWERCAP_DESCRIBE_FASTCHANNEL = 0xc,
+};
+
+enum {
+	POWERCAP_FC_CAP,
+	POWERCAP_FC_PAI,
+	POWERCAP_FC_MAX,
+};
+
+struct scmi_msg_resp_powercap_domain_attributes {
+	__le32 attributes;
+#define SUPPORTS_POWERCAP_CAP_CHANGE_NOTIFY(x)		((x) & BIT(31))
+#define SUPPORTS_POWERCAP_MEASUREMENTS_CHANGE_NOTIFY(x)	((x) & BIT(30))
+#define SUPPORTS_ASYNC_POWERCAP_CAP_SET(x)		((x) & BIT(29))
+#define SUPPORTS_EXTENDED_NAMES(x)			((x) & BIT(28))
+#define SUPPORTS_POWERCAP_CAP_CONFIGURATION(x)		((x) & BIT(27))
+#define SUPPORTS_POWERCAP_MONITORING(x)			((x) & BIT(26))
+#define SUPPORTS_POWERCAP_PAI_CONFIGURATION(x)		((x) & BIT(25))
+#define SUPPORTS_POWERCAP_FASTCHANNELS(x)		((x) & BIT(22))
+#define POWERCAP_POWER_UNIT(x)				\
+		(FIELD_GET(GENMASK(24, 23), (x)))
+#define	SUPPORTS_POWER_UNITS_MW(x)			\
+		(POWERCAP_POWER_UNIT(x) == 0x2)
+#define	SUPPORTS_POWER_UNITS_UW(x)			\
+		(POWERCAP_POWER_UNIT(x) == 0x1)
+	u8 name[SCMI_SHORT_NAME_MAX_SIZE];
+	__le32 min_pai;
+	__le32 max_pai;
+	__le32 pai_step;
+	__le32 min_power_cap;
+	__le32 max_power_cap;
+	__le32 power_cap_step;
+	__le32 sustainable_power;
+	__le32 accuracy;
+	__le32 parent_id;
+};
+
+struct scmi_msg_powercap_set_cap_or_pai {
+	__le32 domain;
+	__le32 flags;
+#define CAP_SET_ASYNC		BIT(1)
+#define CAP_SET_IGNORE_DRESP	BIT(0)
+	__le32 value;
+};
+
+struct scmi_msg_resp_powercap_cap_set_complete {
+	__le32 domain;
+	__le32 power_cap;
+};
+
+struct scmi_msg_resp_powercap_meas_get {
+	__le32 power;
+	__le32 pai;
+};
+
+struct scmi_msg_powercap_notify_cap {
+	__le32 domain;
+	__le32 notify_enable;
+};
+
+struct scmi_msg_powercap_notify_thresh {
+	__le32 domain;
+	__le32 notify_enable;
+	__le32 power_thresh_low;
+	__le32 power_thresh_high;
+};
+
+struct scmi_powercap_cap_changed_notify_payld {
+	__le32 agent_id;
+	__le32 domain_id;
+	__le32 power_cap;
+	__le32 pai;
+};
+
+struct scmi_powercap_meas_changed_notify_payld {
+	__le32 agent_id;
+	__le32 domain_id;
+	__le32 power;
+};
+
+struct scmi_powercap_state {
+	bool meas_notif_enabled;
+	u64 thresholds;
+#define THRESH_LOW(p, id)				\
+	(lower_32_bits((p)->states[(id)].thresholds))
+#define THRESH_HIGH(p, id)				\
+	(upper_32_bits((p)->states[(id)].thresholds))
+};
+
+struct powercap_info {
+	u32 version;
+	int num_domains;
+	struct scmi_powercap_state *states;
+	struct scmi_powercap_info *powercaps;
+};
+
+static enum scmi_powercap_protocol_cmd evt_2_cmd[] = {
+	POWERCAP_CAP_NOTIFY,
+	POWERCAP_MEASUREMENTS_NOTIFY,
+};
+
+static int scmi_powercap_notify(const struct scmi_protocol_handle *ph,
+				u32 domain, int message_id, bool enable);
+
+static int
+scmi_powercap_attributes_get(const struct scmi_protocol_handle *ph,
+			     struct powercap_info *pi)
+{
+	int ret;
+	struct scmi_xfer *t;
+
+	ret = ph->xops->xfer_get_init(ph, PROTOCOL_ATTRIBUTES, 0,
+				      sizeof(u32), &t);
+	if (ret)
+		return ret;
+
+	ret = ph->xops->do_xfer(ph, t);
+	if (!ret) {
+		u32 attributes;
+
+		attributes = get_unaligned_le32(t->rx.buf);
+		pi->num_domains = FIELD_GET(GENMASK(15, 0), attributes);
+	}
+
+	ph->xops->xfer_put(ph, t);
+	return ret;
+}
+
+static inline int
+scmi_powercap_validate(unsigned int min_val, unsigned int max_val,
+		       unsigned int step_val, bool configurable)
+{
+	if (!min_val || !max_val)
+		return -EPROTO;
+
+	if ((configurable && min_val == max_val) ||
+	    (!configurable && min_val != max_val))
+		return -EPROTO;
+
+	if (min_val != max_val && !step_val)
+		return -EPROTO;
+
+	return 0;
+}
+
+static int
+scmi_powercap_domain_attributes_get(const struct scmi_protocol_handle *ph,
+				    struct powercap_info *pinfo, u32 domain)
+{
+	int ret;
+	u32 flags;
+	struct scmi_xfer *t;
+	struct scmi_powercap_info *dom_info = pinfo->powercaps + domain;
+	struct scmi_msg_resp_powercap_domain_attributes *resp;
+
+	ret = ph->xops->xfer_get_init(ph, POWERCAP_DOMAIN_ATTRIBUTES,
+				      sizeof(domain), sizeof(*resp), &t);
+	if (ret)
+		return ret;
+
+	put_unaligned_le32(domain, t->tx.buf);
+	resp = t->rx.buf;
+
+	ret = ph->xops->do_xfer(ph, t);
+	if (!ret) {
+		flags = le32_to_cpu(resp->attributes);
+
+		dom_info->id = domain;
+		dom_info->notify_powercap_cap_change =
+			SUPPORTS_POWERCAP_CAP_CHANGE_NOTIFY(flags);
+		dom_info->notify_powercap_measurement_change =
+			SUPPORTS_POWERCAP_MEASUREMENTS_CHANGE_NOTIFY(flags);
+		dom_info->async_powercap_cap_set =
+			SUPPORTS_ASYNC_POWERCAP_CAP_SET(flags);
+		dom_info->powercap_cap_config =
+			SUPPORTS_POWERCAP_CAP_CONFIGURATION(flags);
+		dom_info->powercap_monitoring =
+			SUPPORTS_POWERCAP_MONITORING(flags);
+		dom_info->powercap_pai_config =
+			SUPPORTS_POWERCAP_PAI_CONFIGURATION(flags);
+		dom_info->powercap_scale_mw =
+			SUPPORTS_POWER_UNITS_MW(flags);
+		dom_info->powercap_scale_uw =
+			SUPPORTS_POWER_UNITS_UW(flags);
+		dom_info->fastchannels =
+			SUPPORTS_POWERCAP_FASTCHANNELS(flags);
+
+		strscpy(dom_info->name, resp->name, SCMI_SHORT_NAME_MAX_SIZE);
+
+		dom_info->min_pai = le32_to_cpu(resp->min_pai);
+		dom_info->max_pai = le32_to_cpu(resp->max_pai);
+		dom_info->pai_step = le32_to_cpu(resp->pai_step);
+		ret = scmi_powercap_validate(dom_info->min_pai,
+					     dom_info->max_pai,
+					     dom_info->pai_step,
+					     dom_info->powercap_pai_config);
+		if (ret) {
+			dev_err(ph->dev,
+				"Platform reported inconsistent PAI config for domain %d - %s\n",
+				dom_info->id, dom_info->name);
+			goto clean;
+		}
+
+		dom_info->min_power_cap = le32_to_cpu(resp->min_power_cap);
+		dom_info->max_power_cap = le32_to_cpu(resp->max_power_cap);
+		dom_info->power_cap_step = le32_to_cpu(resp->power_cap_step);
+		ret = scmi_powercap_validate(dom_info->min_power_cap,
+					     dom_info->max_power_cap,
+					     dom_info->power_cap_step,
+					     dom_info->powercap_cap_config);
+		if (ret) {
+			dev_err(ph->dev,
+				"Platform reported inconsistent CAP config for domain %d - %s\n",
+				dom_info->id, dom_info->name);
+			goto clean;
+		}
+
+		dom_info->sustainable_power =
+			le32_to_cpu(resp->sustainable_power);
+		dom_info->accuracy = le32_to_cpu(resp->accuracy);
+
+		dom_info->parent_id = le32_to_cpu(resp->parent_id);
+		if (dom_info->parent_id != SCMI_POWERCAP_ROOT_ZONE_ID &&
+		    (dom_info->parent_id >= pinfo->num_domains ||
+		     dom_info->parent_id == dom_info->id)) {
+			dev_err(ph->dev,
+				"Platform reported inconsistent parent ID for domain %d - %s\n",
+				dom_info->id, dom_info->name);
+			ret = -ENODEV;
+		}
+	}
+
+clean:
+	ph->xops->xfer_put(ph, t);
+
+	/*
+	 * If supported overwrite short name with the extended one;
+	 * on error just carry on and use already provided short name.
+	 */
+	if (!ret && SUPPORTS_EXTENDED_NAMES(flags))
+		ph->hops->extended_name_get(ph, POWERCAP_DOMAIN_NAME_GET,
+					    domain, dom_info->name,
+					    SCMI_MAX_STR_SIZE);
+
+	return ret;
+}
+
+static int scmi_powercap_num_domains_get(const struct scmi_protocol_handle *ph)
+{
+	struct powercap_info *pi = ph->get_priv(ph);
+
+	return pi->num_domains;
+}
+
+static const struct scmi_powercap_info *
+scmi_powercap_dom_info_get(const struct scmi_protocol_handle *ph, u32 domain_id)
+{
+	struct powercap_info *pi = ph->get_priv(ph);
+
+	if (domain_id >= pi->num_domains)
+		return NULL;
+
+	return pi->powercaps + domain_id;
+}
+
+static int scmi_powercap_xfer_cap_get(const struct scmi_protocol_handle *ph,
+				      u32 domain_id, u32 *power_cap)
+{
+	int ret;
+	struct scmi_xfer *t;
+
+	ret = ph->xops->xfer_get_init(ph, POWERCAP_CAP_GET, sizeof(u32),
+				      sizeof(u32), &t);
+	if (ret)
+		return ret;
+
+	put_unaligned_le32(domain_id, t->tx.buf);
+	ret = ph->xops->do_xfer(ph, t);
+	if (!ret)
+		*power_cap = get_unaligned_le32(t->rx.buf);
+
+	ph->xops->xfer_put(ph, t);
+
+	return ret;
+}
+
+static int scmi_powercap_cap_get(const struct scmi_protocol_handle *ph,
+				 u32 domain_id, u32 *power_cap)
+{
+	struct scmi_powercap_info *dom;
+	struct powercap_info *pi = ph->get_priv(ph);
+
+	if (!power_cap || domain_id >= pi->num_domains)
+		return -EINVAL;
+
+	dom = pi->powercaps + domain_id;
+	if (dom->fc_info && dom->fc_info[POWERCAP_FC_CAP].get_addr) {
+		*power_cap = ioread32(dom->fc_info[POWERCAP_FC_CAP].get_addr);
+		trace_scmi_fc_call(SCMI_PROTOCOL_POWERCAP, POWERCAP_CAP_GET,
+				   domain_id, *power_cap, 0);
+		return 0;
+	}
+
+	return scmi_powercap_xfer_cap_get(ph, domain_id, power_cap);
+}
+
+static int scmi_powercap_xfer_cap_set(const struct scmi_protocol_handle *ph,
+				      const struct scmi_powercap_info *pc,
+				      u32 power_cap, bool ignore_dresp)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_msg_powercap_set_cap_or_pai *msg;
+
+	ret = ph->xops->xfer_get_init(ph, POWERCAP_CAP_SET,
+				      sizeof(*msg), 0, &t);
+	if (ret)
+		return ret;
+
+	msg = t->tx.buf;
+	msg->domain = cpu_to_le32(pc->id);
+	msg->flags =
+		cpu_to_le32(FIELD_PREP(CAP_SET_ASYNC, !!pc->async_powercap_cap_set) |
+			    FIELD_PREP(CAP_SET_IGNORE_DRESP, !!ignore_dresp));
+	msg->value = cpu_to_le32(power_cap);
+
+	if (!pc->async_powercap_cap_set || ignore_dresp) {
+		ret = ph->xops->do_xfer(ph, t);
+	} else {
+		ret = ph->xops->do_xfer_with_response(ph, t);
+		if (!ret) {
+			struct scmi_msg_resp_powercap_cap_set_complete *resp;
+
+			resp = t->rx.buf;
+			if (le32_to_cpu(resp->domain) == pc->id)
+				dev_dbg(ph->dev,
+					"Powercap ID %d CAP set async to %u\n",
+					pc->id,
+					get_unaligned_le32(&resp->power_cap));
+			else
+				ret = -EPROTO;
+		}
+	}
+
+	ph->xops->xfer_put(ph, t);
+	return ret;
+}
+
+static int scmi_powercap_cap_set(const struct scmi_protocol_handle *ph,
+				 u32 domain_id, u32 power_cap,
+				 bool ignore_dresp)
+{
+	const struct scmi_powercap_info *pc;
+
+	pc = scmi_powercap_dom_info_get(ph, domain_id);
+	if (!pc || !pc->powercap_cap_config || !power_cap ||
+	    power_cap < pc->min_power_cap ||
+	    power_cap > pc->max_power_cap)
+		return -EINVAL;
+
+	if (pc->fc_info && pc->fc_info[POWERCAP_FC_CAP].set_addr) {
+		struct scmi_fc_info *fci = &pc->fc_info[POWERCAP_FC_CAP];
+
+		iowrite32(power_cap, fci->set_addr);
+		ph->hops->fastchannel_db_ring(fci->set_db);
+		trace_scmi_fc_call(SCMI_PROTOCOL_POWERCAP, POWERCAP_CAP_SET,
+				   domain_id, power_cap, 0);
+		return 0;
+	}
+
+	return scmi_powercap_xfer_cap_set(ph, pc, power_cap, ignore_dresp);
+}
+
+static int scmi_powercap_xfer_pai_get(const struct scmi_protocol_handle *ph,
+				      u32 domain_id, u32 *pai)
+{
+	int ret;
+	struct scmi_xfer *t;
+
+	ret = ph->xops->xfer_get_init(ph, POWERCAP_PAI_GET, sizeof(u32),
+				      sizeof(u32), &t);
+	if (ret)
+		return ret;
+
+	put_unaligned_le32(domain_id, t->tx.buf);
+	ret = ph->xops->do_xfer(ph, t);
+	if (!ret)
+		*pai = get_unaligned_le32(t->rx.buf);
+
+	ph->xops->xfer_put(ph, t);
+
+	return ret;
+}
+
+static int scmi_powercap_pai_get(const struct scmi_protocol_handle *ph,
+				 u32 domain_id, u32 *pai)
+{
+	struct scmi_powercap_info *dom;
+	struct powercap_info *pi = ph->get_priv(ph);
+
+	if (!pai || domain_id >= pi->num_domains)
+		return -EINVAL;
+
+	dom = pi->powercaps + domain_id;
+	if (dom->fc_info && dom->fc_info[POWERCAP_FC_PAI].get_addr) {
+		*pai = ioread32(dom->fc_info[POWERCAP_FC_PAI].get_addr);
+		trace_scmi_fc_call(SCMI_PROTOCOL_POWERCAP, POWERCAP_PAI_GET,
+				   domain_id, *pai, 0);
+		return 0;
+	}
+
+	return scmi_powercap_xfer_pai_get(ph, domain_id, pai);
+}
+
+static int scmi_powercap_xfer_pai_set(const struct scmi_protocol_handle *ph,
+				      u32 domain_id, u32 pai)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_msg_powercap_set_cap_or_pai *msg;
+
+	ret = ph->xops->xfer_get_init(ph, POWERCAP_PAI_SET,
+				      sizeof(*msg), 0, &t);
+	if (ret)
+		return ret;
+
+	msg = t->tx.buf;
+	msg->domain = cpu_to_le32(domain_id);
+	msg->flags = cpu_to_le32(0);
+	msg->value = cpu_to_le32(pai);
+
+	ret = ph->xops->do_xfer(ph, t);
+
+	ph->xops->xfer_put(ph, t);
+	return ret;
+}
+
+static int scmi_powercap_pai_set(const struct scmi_protocol_handle *ph,
+				 u32 domain_id, u32 pai)
+{
+	const struct scmi_powercap_info *pc;
+
+	pc = scmi_powercap_dom_info_get(ph, domain_id);
+	if (!pc || !pc->powercap_pai_config || !pai ||
+	    pai < pc->min_pai || pai > pc->max_pai)
+		return -EINVAL;
+
+	if (pc->fc_info && pc->fc_info[POWERCAP_FC_PAI].set_addr) {
+		struct scmi_fc_info *fci = &pc->fc_info[POWERCAP_FC_PAI];
+
+		trace_scmi_fc_call(SCMI_PROTOCOL_POWERCAP, POWERCAP_PAI_SET,
+				   domain_id, pai, 0);
+		iowrite32(pai, fci->set_addr);
+		ph->hops->fastchannel_db_ring(fci->set_db);
+		return 0;
+	}
+
+	return scmi_powercap_xfer_pai_set(ph, domain_id, pai);
+}
+
+static int scmi_powercap_measurements_get(const struct scmi_protocol_handle *ph,
+					  u32 domain_id, u32 *average_power,
+					  u32 *pai)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_msg_resp_powercap_meas_get *resp;
+	const struct scmi_powercap_info *pc;
+
+	pc = scmi_powercap_dom_info_get(ph, domain_id);
+	if (!pc || !pc->powercap_monitoring || !pai || !average_power)
+		return -EINVAL;
+
+	ret = ph->xops->xfer_get_init(ph, POWERCAP_MEASUREMENTS_GET,
+				      sizeof(u32), sizeof(*resp), &t);
+	if (ret)
+		return ret;
+
+	resp = t->rx.buf;
+	put_unaligned_le32(domain_id, t->tx.buf);
+	ret = ph->xops->do_xfer(ph, t);
+	if (!ret) {
+		*average_power = le32_to_cpu(resp->power);
+		*pai = le32_to_cpu(resp->pai);
+	}
+
+	ph->xops->xfer_put(ph, t);
+	return ret;
+}
+
+static int
+scmi_powercap_measurements_threshold_get(const struct scmi_protocol_handle *ph,
+					 u32 domain_id, u32 *power_thresh_low,
+					 u32 *power_thresh_high)
+{
+	struct powercap_info *pi = ph->get_priv(ph);
+
+	if (!power_thresh_low || !power_thresh_high ||
+	    domain_id >= pi->num_domains)
+		return -EINVAL;
+
+	*power_thresh_low =  THRESH_LOW(pi, domain_id);
+	*power_thresh_high = THRESH_HIGH(pi, domain_id);
+
+	return 0;
+}
+
+static int
+scmi_powercap_measurements_threshold_set(const struct scmi_protocol_handle *ph,
+					 u32 domain_id, u32 power_thresh_low,
+					 u32 power_thresh_high)
+{
+	int ret = 0;
+	struct powercap_info *pi = ph->get_priv(ph);
+
+	if (domain_id >= pi->num_domains ||
+	    power_thresh_low > power_thresh_high)
+		return -EINVAL;
+
+	/* Anything to do ? */
+	if (THRESH_LOW(pi, domain_id) == power_thresh_low &&
+	    THRESH_HIGH(pi, domain_id) == power_thresh_high)
+		return ret;
+
+	pi->states[domain_id].thresholds =
+		(FIELD_PREP(GENMASK_ULL(31, 0), power_thresh_low) |
+		 FIELD_PREP(GENMASK_ULL(63, 32), power_thresh_high));
+
+	/* Update thresholds if notification already enabled */
+	if (pi->states[domain_id].meas_notif_enabled)
+		ret = scmi_powercap_notify(ph, domain_id,
+					   POWERCAP_MEASUREMENTS_NOTIFY,
+					   true);
+
+	return ret;
+}
+
+static const struct scmi_powercap_proto_ops powercap_proto_ops = {
+	.num_domains_get = scmi_powercap_num_domains_get,
+	.info_get = scmi_powercap_dom_info_get,
+	.cap_get = scmi_powercap_cap_get,
+	.cap_set = scmi_powercap_cap_set,
+	.pai_get = scmi_powercap_pai_get,
+	.pai_set = scmi_powercap_pai_set,
+	.measurements_get = scmi_powercap_measurements_get,
+	.measurements_threshold_set = scmi_powercap_measurements_threshold_set,
+	.measurements_threshold_get = scmi_powercap_measurements_threshold_get,
+};
+
+static void scmi_powercap_domain_init_fc(const struct scmi_protocol_handle *ph,
+					 u32 domain, struct scmi_fc_info **p_fc)
+{
+	struct scmi_fc_info *fc;
+
+	fc = devm_kcalloc(ph->dev, POWERCAP_FC_MAX, sizeof(*fc), GFP_KERNEL);
+	if (!fc)
+		return;
+
+	ph->hops->fastchannel_init(ph, POWERCAP_DESCRIBE_FASTCHANNEL,
+				   POWERCAP_CAP_SET, 4, domain,
+				   &fc[POWERCAP_FC_CAP].set_addr,
+				   &fc[POWERCAP_FC_CAP].set_db);
+
+	ph->hops->fastchannel_init(ph, POWERCAP_DESCRIBE_FASTCHANNEL,
+				   POWERCAP_CAP_GET, 4, domain,
+				   &fc[POWERCAP_FC_CAP].get_addr, NULL);
+
+	ph->hops->fastchannel_init(ph, POWERCAP_DESCRIBE_FASTCHANNEL,
+				   POWERCAP_PAI_SET, 4, domain,
+				   &fc[POWERCAP_FC_PAI].set_addr,
+				   &fc[POWERCAP_FC_PAI].set_db);
+
+	ph->hops->fastchannel_init(ph, POWERCAP_DESCRIBE_FASTCHANNEL,
+				   POWERCAP_PAI_GET, 4, domain,
+				   &fc[POWERCAP_FC_PAI].get_addr, NULL);
+
+	*p_fc = fc;
+}
+
+static int scmi_powercap_notify(const struct scmi_protocol_handle *ph,
+				u32 domain, int message_id, bool enable)
+{
+	int ret;
+	struct scmi_xfer *t;
+
+	switch (message_id) {
+	case POWERCAP_CAP_NOTIFY:
+	{
+		struct scmi_msg_powercap_notify_cap *notify;
+
+		ret = ph->xops->xfer_get_init(ph, message_id,
+					      sizeof(*notify), 0, &t);
+		if (ret)
+			return ret;
+
+		notify = t->tx.buf;
+		notify->domain = cpu_to_le32(domain);
+		notify->notify_enable = cpu_to_le32(enable ? BIT(0) : 0);
+		break;
+	}
+	case POWERCAP_MEASUREMENTS_NOTIFY:
+	{
+		u32 low, high;
+		struct scmi_msg_powercap_notify_thresh *notify;
+
+		/*
+		 * Note that we have to pick the most recently configured
+		 * thresholds to build a proper POWERCAP_MEASUREMENTS_NOTIFY
+		 * enable request and we fail, complaining, if no thresholds
+		 * were ever set, since this is an indication the API has been
+		 * used wrongly.
+		 */
+		ret = scmi_powercap_measurements_threshold_get(ph, domain,
+							       &low, &high);
+		if (ret)
+			return ret;
+
+		if (enable && !low && !high) {
+			dev_err(ph->dev,
+				"Invalid Measurements Notify thresholds: %u/%u\n",
+				low, high);
+			return -EINVAL;
+		}
+
+		ret = ph->xops->xfer_get_init(ph, message_id,
+					      sizeof(*notify), 0, &t);
+		if (ret)
+			return ret;
+
+		notify = t->tx.buf;
+		notify->domain = cpu_to_le32(domain);
+		notify->notify_enable = cpu_to_le32(enable ? BIT(0) : 0);
+		notify->power_thresh_low = cpu_to_le32(low);
+		notify->power_thresh_high = cpu_to_le32(high);
+		break;
+	}
+	default:
+		return -EINVAL;
+	}
+
+	ret = ph->xops->do_xfer(ph, t);
+
+	ph->xops->xfer_put(ph, t);
+	return ret;
+}
+
+static int
+scmi_powercap_set_notify_enabled(const struct scmi_protocol_handle *ph,
+				 u8 evt_id, u32 src_id, bool enable)
+{
+	int ret, cmd_id;
+	struct powercap_info *pi = ph->get_priv(ph);
+
+	if (evt_id >= ARRAY_SIZE(evt_2_cmd) || src_id >= pi->num_domains)
+		return -EINVAL;
+
+	cmd_id = evt_2_cmd[evt_id];
+	ret = scmi_powercap_notify(ph, src_id, cmd_id, enable);
+	if (ret)
+		pr_debug("FAIL_ENABLED - evt[%X] dom[%d] - ret:%d\n",
+			 evt_id, src_id, ret);
+	else if (cmd_id == POWERCAP_MEASUREMENTS_NOTIFY)
+		/*
+		 * On success save the current notification enabled state, so
+		 * as to be able to properly update the notification thresholds
+		 * when they are modified on a domain for which measurement
+		 * notifications were currently enabled.
+		 *
+		 * This is needed because the SCMI Notification core machinery
+		 * and API does not support passing per-notification custom
+		 * arguments at callback registration time.
+		 *
+		 * Note that this can be done here with a simple flag since the
+		 * SCMI core Notifications code takes care of keeping proper
+		 * per-domain enables refcounting, so that this helper function
+		 * will be called only once (for enables) when the first user
+		 * registers a callback on this domain and once more (disable)
+		 * when the last user de-registers its callback.
+		 */
+		pi->states[src_id].meas_notif_enabled = enable;
+
+	return ret;
+}
+
+static void *
+scmi_powercap_fill_custom_report(const struct scmi_protocol_handle *ph,
+				 u8 evt_id, ktime_t timestamp,
+				 const void *payld, size_t payld_sz,
+				 void *report, u32 *src_id)
+{
+	void *rep = NULL;
+
+	switch (evt_id) {
+	case SCMI_EVENT_POWERCAP_CAP_CHANGED:
+	{
+		const struct scmi_powercap_cap_changed_notify_payld *p = payld;
+		struct scmi_powercap_cap_changed_report *r = report;
+
+		if (sizeof(*p) != payld_sz)
+			break;
+
+		r->timestamp = timestamp;
+		r->agent_id = le32_to_cpu(p->agent_id);
+		r->domain_id = le32_to_cpu(p->domain_id);
+		r->power_cap = le32_to_cpu(p->power_cap);
+		r->pai = le32_to_cpu(p->pai);
+		*src_id = r->domain_id;
+		rep = r;
+		break;
+	}
+	case SCMI_EVENT_POWERCAP_MEASUREMENTS_CHANGED:
+	{
+		const struct scmi_powercap_meas_changed_notify_payld *p = payld;
+		struct scmi_powercap_meas_changed_report *r = report;
+
+		if (sizeof(*p) != payld_sz)
+			break;
+
+		r->timestamp = timestamp;
+		r->agent_id = le32_to_cpu(p->agent_id);
+		r->domain_id = le32_to_cpu(p->domain_id);
+		r->power = le32_to_cpu(p->power);
+		*src_id = r->domain_id;
+		rep = r;
+		break;
+	}
+	default:
+		break;
+	}
+
+	return rep;
+}
+
+static int
+scmi_powercap_get_num_sources(const struct scmi_protocol_handle *ph)
+{
+	struct powercap_info *pi = ph->get_priv(ph);
+
+	if (!pi)
+		return -EINVAL;
+
+	return pi->num_domains;
+}
+
+static const struct scmi_event powercap_events[] = {
+	{
+		.id = SCMI_EVENT_POWERCAP_CAP_CHANGED,
+		.max_payld_sz =
+			sizeof(struct scmi_powercap_cap_changed_notify_payld),
+		.max_report_sz =
+			sizeof(struct scmi_powercap_cap_changed_report),
+	},
+	{
+		.id = SCMI_EVENT_POWERCAP_MEASUREMENTS_CHANGED,
+		.max_payld_sz =
+			sizeof(struct scmi_powercap_meas_changed_notify_payld),
+		.max_report_sz =
+			sizeof(struct scmi_powercap_meas_changed_report),
+	},
+};
+
+static const struct scmi_event_ops powercap_event_ops = {
+	.get_num_sources = scmi_powercap_get_num_sources,
+	.set_notify_enabled = scmi_powercap_set_notify_enabled,
+	.fill_custom_report = scmi_powercap_fill_custom_report,
+};
+
+static const struct scmi_protocol_events powercap_protocol_events = {
+	.queue_sz = SCMI_PROTO_QUEUE_SZ,
+	.ops = &powercap_event_ops,
+	.evts = powercap_events,
+	.num_events = ARRAY_SIZE(powercap_events),
+};
+
+static int
+scmi_powercap_protocol_init(const struct scmi_protocol_handle *ph)
+{
+	int domain, ret;
+	u32 version;
+	struct powercap_info *pinfo;
+
+	ret = ph->xops->version_get(ph, &version);
+	if (ret)
+		return ret;
+
+	dev_dbg(ph->dev, "Powercap Version %d.%d\n",
+		PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
+
+	pinfo = devm_kzalloc(ph->dev, sizeof(*pinfo), GFP_KERNEL);
+	if (!pinfo)
+		return -ENOMEM;
+
+	ret = scmi_powercap_attributes_get(ph, pinfo);
+	if (ret)
+		return ret;
+
+	pinfo->powercaps = devm_kcalloc(ph->dev, pinfo->num_domains,
+					sizeof(*pinfo->powercaps),
+					GFP_KERNEL);
+	if (!pinfo->powercaps)
+		return -ENOMEM;
+
+	/*
+	 * Note that any failure in retrieving any domain attribute leads to
+	 * the whole Powercap protocol initialization failure: this way the
+	 * reported Powercap domains are all assured, when accessed, to be well
+	 * formed and correlated by sane parent-child relationship (if any).
+	 */
+	for (domain = 0; domain < pinfo->num_domains; domain++) {
+		ret = scmi_powercap_domain_attributes_get(ph, pinfo, domain);
+		if (ret)
+			return ret;
+
+		if (pinfo->powercaps[domain].fastchannels)
+			scmi_powercap_domain_init_fc(ph, domain,
+						     &pinfo->powercaps[domain].fc_info);
+	}
+
+	pinfo->states = devm_kcalloc(ph->dev, pinfo->num_domains,
+				     sizeof(*pinfo->states), GFP_KERNEL);
+	if (!pinfo->states)
+		return -ENOMEM;
+
+	pinfo->version = version;
+
+	return ph->set_priv(ph, pinfo);
+}
+
+static const struct scmi_protocol scmi_powercap = {
+	.id = SCMI_PROTOCOL_POWERCAP,
+	.owner = THIS_MODULE,
+	.instance_init = &scmi_powercap_protocol_init,
+	.ops = &powercap_proto_ops,
+	.events = &powercap_protocol_events,
+};
+
+DEFINE_SCMI_PROTOCOL_REGISTER_UNREGISTER(powercap, scmi_powercap)
diff --git a/drivers/firmware/arm_scmi/protocols.h b/drivers/firmware/arm_scmi/protocols.h
index 51c31379f9b3..2f3bf691db7c 100644
--- a/drivers/firmware/arm_scmi/protocols.h
+++ b/drivers/firmware/arm_scmi/protocols.h
@@ -215,6 +215,19 @@ struct scmi_iterator_ops {
 				struct scmi_iterator_state *st, void *priv);
 };
 
+struct scmi_fc_db_info {
+	int width;
+	u64 set;
+	u64 mask;
+	void __iomem *addr;
+};
+
+struct scmi_fc_info {
+	void __iomem *set_addr;
+	void __iomem *get_addr;
+	struct scmi_fc_db_info *set_db;
+};
+
 /**
  * struct scmi_proto_helpers_ops  - References to common protocol helpers
  * @extended_name_get: A common helper function to retrieve extended naming
@@ -230,6 +243,9 @@ struct scmi_iterator_ops {
  *			provided in @ops.
  * @iter_response_run: A common helper to trigger the run of a previously
  *		       initialized iterator.
+ * @fastchannel_init: A common helper used to initialize FC descriptors by
+ *		      gathering FC descriptions from the SCMI platform server.
+ * @fastchannel_db_ring: A common helper to ring a FC doorbell.
  */
 struct scmi_proto_helpers_ops {
 	int (*extended_name_get)(const struct scmi_protocol_handle *ph,
@@ -239,6 +255,12 @@ struct scmi_proto_helpers_ops {
 				    unsigned int max_resources, u8 msg_id,
 				    size_t tx_size, void *priv);
 	int (*iter_response_run)(void *iter);
+	void (*fastchannel_init)(const struct scmi_protocol_handle *ph,
+				 u8 describe_id, u32 message_id,
+				 u32 valid_size, u32 domain,
+				 void __iomem **p_addr,
+				 struct scmi_fc_db_info **p_db);
+	void (*fastchannel_db_ring)(struct scmi_fc_db_info *db);
 };
 
 /**
@@ -315,5 +337,6 @@ DECLARE_SCMI_REGISTER_UNREGISTER(reset);
 DECLARE_SCMI_REGISTER_UNREGISTER(sensors);
 DECLARE_SCMI_REGISTER_UNREGISTER(voltage);
 DECLARE_SCMI_REGISTER_UNREGISTER(system);
+DECLARE_SCMI_REGISTER_UNREGISTER(powercap);
 
 #endif /* _SCMI_PROTOCOLS_H */
diff --git a/drivers/firmware/arm_scmi/scmi_power_control.c b/drivers/firmware/arm_scmi/scmi_power_control.c
new file mode 100644
index 000000000000..6eb7d2a4b6b1
--- /dev/null
+++ b/drivers/firmware/arm_scmi/scmi_power_control.c
@@ -0,0 +1,362 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SCMI Generic SystemPower Control driver.
+ *
+ * Copyright (C) 2020-2022 ARM Ltd.
+ */
+/*
+ * In order to handle platform originated SCMI SystemPower requests (like
+ * shutdowns or cold/warm resets) we register an SCMI Notification notifier
+ * block to react when such SCMI SystemPower events are emitted by platform.
+ *
+ * Once such a notification is received we act accordingly to perform the
+ * required system transition depending on the kind of request.
+ *
+ * Graceful requests are routed to userspace through the same API methods
+ * (orderly_poweroff/reboot()) used by ACPI when handling ACPI Shutdown bus
+ * events.
+ *
+ * Direct forceful requests are not supported since are not meant to be sent
+ * by the SCMI platform to an OSPM like Linux.
+ *
+ * Additionally, graceful request notifications can carry an optional timeout
+ * field stating the maximum amount of time allowed by the platform for
+ * completion after which they are converted to forceful ones: the assumption
+ * here is that even graceful requests can be upper-bound by a maximum final
+ * timeout strictly enforced by the platform itself which can ultimately cut
+ * the power off at will anytime; in order to avoid such extreme scenario, we
+ * track progress of graceful requests through the means of a reboot notifier
+ * converting timed-out graceful requests to forceful ones, so at least we
+ * try to perform a clean sync and shutdown/restart before the power is cut.
+ *
+ * Given the peculiar nature of SCMI SystemPower protocol, that is being in
+ * charge of triggering system wide shutdown/reboot events, there should be
+ * only one SCMI platform actively emitting SystemPower events.
+ * For this reason the SCMI core takes care to enforce the creation of one
+ * single unique device associated to the SCMI System Power protocol; no matter
+ * how many SCMI platforms are defined on the system, only one can be designated
+ * to support System Power: as a consequence this driver will never be probed
+ * more than once.
+ *
+ * For similar reasons as soon as the first valid SystemPower is received by
+ * this driver and the shutdown/reboot is started, any further notification
+ * possibly emitted by the platform will be ignored.
+ */
+
+#include <linux/math.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/printk.h>
+#include <linux/reboot.h>
+#include <linux/scmi_protocol.h>
+#include <linux/slab.h>
+#include <linux/time64.h>
+#include <linux/timer.h>
+#include <linux/types.h>
+#include <linux/workqueue.h>
+
+#ifndef MODULE
+#include <linux/fs.h>
+#endif
+
+enum scmi_syspower_state {
+	SCMI_SYSPOWER_IDLE,
+	SCMI_SYSPOWER_IN_PROGRESS,
+	SCMI_SYSPOWER_REBOOTING
+};
+
+/**
+ * struct scmi_syspower_conf  -  Common configuration
+ *
+ * @dev: A reference device
+ * @state: Current SystemPower state
+ * @state_mtx: @state related mutex
+ * @required_transition: The requested transition as decribed in the received
+ *			 SCMI SystemPower notification
+ * @userspace_nb: The notifier_block registered against the SCMI SystemPower
+ *		  notification to start the needed userspace interactions.
+ * @reboot_nb: A notifier_block optionally used to track reboot progress
+ * @forceful_work: A worker used to trigger a forceful transition once a
+ *		   graceful has timed out.
+ */
+struct scmi_syspower_conf {
+	struct device *dev;
+	enum scmi_syspower_state state;
+	/* Protect access to state */
+	struct mutex state_mtx;
+	enum scmi_system_events required_transition;
+
+	struct notifier_block userspace_nb;
+	struct notifier_block reboot_nb;
+
+	struct delayed_work forceful_work;
+};
+
+#define userspace_nb_to_sconf(x)	\
+	container_of(x, struct scmi_syspower_conf, userspace_nb)
+
+#define reboot_nb_to_sconf(x)		\
+	container_of(x, struct scmi_syspower_conf, reboot_nb)
+
+#define dwork_to_sconf(x)		\
+	container_of(x, struct scmi_syspower_conf, forceful_work)
+
+/**
+ * scmi_reboot_notifier  - A reboot notifier to catch an ongoing successful
+ * system transition
+ * @nb: Reference to the related notifier block
+ * @reason: The reason for the ongoing reboot
+ * @__unused: The cmd being executed on a restart request (unused)
+ *
+ * When an ongoing system transition is detected, compatible with the one
+ * requested by SCMI, cancel the delayed work.
+ *
+ * Return: NOTIFY_OK in any case
+ */
+static int scmi_reboot_notifier(struct notifier_block *nb,
+				unsigned long reason, void *__unused)
+{
+	struct scmi_syspower_conf *sc = reboot_nb_to_sconf(nb);
+
+	mutex_lock(&sc->state_mtx);
+	switch (reason) {
+	case SYS_HALT:
+	case SYS_POWER_OFF:
+		if (sc->required_transition == SCMI_SYSTEM_SHUTDOWN)
+			sc->state = SCMI_SYSPOWER_REBOOTING;
+		break;
+	case SYS_RESTART:
+		if (sc->required_transition == SCMI_SYSTEM_COLDRESET ||
+		    sc->required_transition == SCMI_SYSTEM_WARMRESET)
+			sc->state = SCMI_SYSPOWER_REBOOTING;
+		break;
+	default:
+		break;
+	}
+
+	if (sc->state == SCMI_SYSPOWER_REBOOTING) {
+		dev_dbg(sc->dev, "Reboot in progress...cancel delayed work.\n");
+		cancel_delayed_work_sync(&sc->forceful_work);
+	}
+	mutex_unlock(&sc->state_mtx);
+
+	return NOTIFY_OK;
+}
+
+/**
+ * scmi_request_forceful_transition  - Request forceful SystemPower transition
+ * @sc: A reference to the configuration data
+ *
+ * Initiates the required SystemPower transition without involving userspace:
+ * just trigger the action at the kernel level after issuing an emergency
+ * sync. (if possible at all)
+ */
+static inline void
+scmi_request_forceful_transition(struct scmi_syspower_conf *sc)
+{
+	dev_dbg(sc->dev, "Serving forceful request:%d\n",
+		sc->required_transition);
+
+#ifndef MODULE
+	emergency_sync();
+#endif
+	switch (sc->required_transition) {
+	case SCMI_SYSTEM_SHUTDOWN:
+		kernel_power_off();
+		break;
+	case SCMI_SYSTEM_COLDRESET:
+	case SCMI_SYSTEM_WARMRESET:
+		kernel_restart(NULL);
+		break;
+	default:
+		break;
+	}
+}
+
+static void scmi_forceful_work_func(struct work_struct *work)
+{
+	struct scmi_syspower_conf *sc;
+	struct delayed_work *dwork;
+
+	if (system_state > SYSTEM_RUNNING)
+		return;
+
+	dwork = to_delayed_work(work);
+	sc = dwork_to_sconf(dwork);
+
+	dev_dbg(sc->dev, "Graceful request timed out...forcing !\n");
+	mutex_lock(&sc->state_mtx);
+	/* avoid deadlock by unregistering reboot notifier first */
+	unregister_reboot_notifier(&sc->reboot_nb);
+	if (sc->state == SCMI_SYSPOWER_IN_PROGRESS)
+		scmi_request_forceful_transition(sc);
+	mutex_unlock(&sc->state_mtx);
+}
+
+/**
+ * scmi_request_graceful_transition  - Request graceful SystemPower transition
+ * @sc: A reference to the configuration data
+ * @timeout_ms: The desired timeout to wait for the shutdown to complete before
+ *		system is forcibly shutdown.
+ *
+ * Initiates the required SystemPower transition, requesting userspace
+ * co-operation: it uses the same orderly_ methods used by ACPI Shutdown event
+ * processing.
+ *
+ * Takes care also to register a reboot notifier and to schedule a delayed work
+ * in order to detect if userspace actions are taking too long and in such a
+ * case to trigger a forceful transition.
+ */
+static void scmi_request_graceful_transition(struct scmi_syspower_conf *sc,
+					     unsigned int timeout_ms)
+{
+	unsigned int adj_timeout_ms = 0;
+
+	if (timeout_ms) {
+		int ret;
+
+		sc->reboot_nb.notifier_call = &scmi_reboot_notifier;
+		ret = register_reboot_notifier(&sc->reboot_nb);
+		if (!ret) {
+			/* Wait only up to 75% of the advertised timeout */
+			adj_timeout_ms = mult_frac(timeout_ms, 3, 4);
+			INIT_DELAYED_WORK(&sc->forceful_work,
+					  scmi_forceful_work_func);
+			schedule_delayed_work(&sc->forceful_work,
+					      msecs_to_jiffies(adj_timeout_ms));
+		} else {
+			/* Carry on best effort even without a reboot notifier */
+			dev_warn(sc->dev,
+				 "Cannot register reboot notifier !\n");
+		}
+	}
+
+	dev_dbg(sc->dev,
+		"Serving graceful req:%d (timeout_ms:%u  adj_timeout_ms:%u)\n",
+		sc->required_transition, timeout_ms, adj_timeout_ms);
+
+	switch (sc->required_transition) {
+	case SCMI_SYSTEM_SHUTDOWN:
+		/*
+		 * When triggered early at boot-time the 'orderly' call will
+		 * partially fail due to the lack of userspace itself, but
+		 * the force=true argument will start anyway a successful
+		 * forced shutdown.
+		 */
+		orderly_poweroff(true);
+		break;
+	case SCMI_SYSTEM_COLDRESET:
+	case SCMI_SYSTEM_WARMRESET:
+		orderly_reboot();
+		break;
+	default:
+		break;
+	}
+}
+
+/**
+ * scmi_userspace_notifier  - Notifier callback to act on SystemPower
+ * Notifications
+ * @nb: Reference to the related notifier block
+ * @event: The SystemPower notification event id
+ * @data: The SystemPower event report
+ *
+ * This callback is in charge of decoding the received SystemPower report
+ * and act accordingly triggering a graceful or forceful system transition.
+ *
+ * Note that once a valid SCMI SystemPower event starts being served, any
+ * other following SystemPower notification received from the same SCMI
+ * instance (handle) will be ignored.
+ *
+ * Return: NOTIFY_OK once a valid SystemPower event has been successfully
+ * processed.
+ */
+static int scmi_userspace_notifier(struct notifier_block *nb,
+				   unsigned long event, void *data)
+{
+	struct scmi_system_power_state_notifier_report *er = data;
+	struct scmi_syspower_conf *sc = userspace_nb_to_sconf(nb);
+
+	if (er->system_state >= SCMI_SYSTEM_POWERUP) {
+		dev_err(sc->dev, "Ignoring unsupported system_state: 0x%X\n",
+			er->system_state);
+		return NOTIFY_DONE;
+	}
+
+	if (!SCMI_SYSPOWER_IS_REQUEST_GRACEFUL(er->flags)) {
+		dev_err(sc->dev, "Ignoring forceful notification.\n");
+		return NOTIFY_DONE;
+	}
+
+	/*
+	 * Bail out if system is already shutting down or an SCMI SystemPower
+	 * requested is already being served.
+	 */
+	if (system_state > SYSTEM_RUNNING)
+		return NOTIFY_DONE;
+	mutex_lock(&sc->state_mtx);
+	if (sc->state != SCMI_SYSPOWER_IDLE) {
+		dev_dbg(sc->dev,
+			"Transition already in progress...ignore.\n");
+		mutex_unlock(&sc->state_mtx);
+		return NOTIFY_DONE;
+	}
+	sc->state = SCMI_SYSPOWER_IN_PROGRESS;
+	mutex_unlock(&sc->state_mtx);
+
+	sc->required_transition = er->system_state;
+
+	/* Leaving a trace in logs of who triggered the shutdown/reboot. */
+	dev_info(sc->dev, "Serving shutdown/reboot request: %d\n",
+		 sc->required_transition);
+
+	scmi_request_graceful_transition(sc, er->timeout);
+
+	return NOTIFY_OK;
+}
+
+static int scmi_syspower_probe(struct scmi_device *sdev)
+{
+	int ret;
+	struct scmi_syspower_conf *sc;
+	struct scmi_handle *handle = sdev->handle;
+
+	if (!handle)
+		return -ENODEV;
+
+	ret = handle->devm_protocol_acquire(sdev, SCMI_PROTOCOL_SYSTEM);
+	if (ret)
+		return ret;
+
+	sc = devm_kzalloc(&sdev->dev, sizeof(*sc), GFP_KERNEL);
+	if (!sc)
+		return -ENOMEM;
+
+	sc->state = SCMI_SYSPOWER_IDLE;
+	mutex_init(&sc->state_mtx);
+	sc->required_transition = SCMI_SYSTEM_MAX;
+	sc->userspace_nb.notifier_call = &scmi_userspace_notifier;
+	sc->dev = &sdev->dev;
+
+	return handle->notify_ops->devm_event_notifier_register(sdev,
+							   SCMI_PROTOCOL_SYSTEM,
+					 SCMI_EVENT_SYSTEM_POWER_STATE_NOTIFIER,
+						       NULL, &sc->userspace_nb);
+}
+
+static const struct scmi_device_id scmi_id_table[] = {
+	{ SCMI_PROTOCOL_SYSTEM, "syspower" },
+	{ },
+};
+MODULE_DEVICE_TABLE(scmi, scmi_id_table);
+
+static struct scmi_driver scmi_system_power_driver = {
+	.name = "scmi-system-power",
+	.probe = scmi_syspower_probe,
+	.id_table = scmi_id_table,
+};
+module_scmi_driver(scmi_system_power_driver);
+
+MODULE_AUTHOR("Cristian Marussi <cristian.marussi@arm.com>");
+MODULE_DESCRIPTION("ARM SCMI SystemPower Control driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/firmware/arm_scmi/system.c b/drivers/firmware/arm_scmi/system.c
index 220e399118ad..9383d7584539 100644
--- a/drivers/firmware/arm_scmi/system.c
+++ b/drivers/firmware/arm_scmi/system.c
@@ -27,10 +27,12 @@ struct scmi_system_power_state_notifier_payld {
 	__le32 agent_id;
 	__le32 flags;
 	__le32 system_state;
+	__le32 timeout;
 };
 
 struct scmi_system_info {
 	u32 version;
+	bool graceful_timeout_supported;
 };
 
 static int scmi_system_request_notify(const struct scmi_protocol_handle *ph,
@@ -72,17 +74,27 @@ scmi_system_fill_custom_report(const struct scmi_protocol_handle *ph,
 			       const void *payld, size_t payld_sz,
 			       void *report, u32 *src_id)
 {
+	size_t expected_sz;
 	const struct scmi_system_power_state_notifier_payld *p = payld;
 	struct scmi_system_power_state_notifier_report *r = report;
+	struct scmi_system_info *pinfo = ph->get_priv(ph);
 
+	expected_sz = pinfo->graceful_timeout_supported ?
+			sizeof(*p) : sizeof(*p) - sizeof(__le32);
 	if (evt_id != SCMI_EVENT_SYSTEM_POWER_STATE_NOTIFIER ||
-	    sizeof(*p) != payld_sz)
+	    payld_sz != expected_sz)
 		return NULL;
 
 	r->timestamp = timestamp;
 	r->agent_id = le32_to_cpu(p->agent_id);
 	r->flags = le32_to_cpu(p->flags);
 	r->system_state = le32_to_cpu(p->system_state);
+	if (pinfo->graceful_timeout_supported &&
+	    r->system_state == SCMI_SYSTEM_SHUTDOWN &&
+	    SCMI_SYSPOWER_IS_REQUEST_GRACEFUL(r->flags))
+		r->timeout = le32_to_cpu(p->timeout);
+	else
+		r->timeout = 0x00;
 	*src_id = 0;
 
 	return r;
@@ -129,6 +141,9 @@ static int scmi_system_protocol_init(const struct scmi_protocol_handle *ph)
 		return -ENOMEM;
 
 	pinfo->version = version;
+	if (PROTOCOL_REV_MAJOR(pinfo->version) >= 0x2)
+		pinfo->graceful_timeout_supported = true;
+
 	return ph->set_priv(ph, pinfo);
 }
 
diff --git a/drivers/firmware/arm_scpi.c b/drivers/firmware/arm_scpi.c
index ddf0b9ff9e15..435d0e2658a4 100644
--- a/drivers/firmware/arm_scpi.c
+++ b/drivers/firmware/arm_scpi.c
@@ -815,7 +815,7 @@ static int scpi_init_versions(struct scpi_drvinfo *info)
 		info->firmware_version = le32_to_cpu(caps.platform_version);
 	}
 	/* Ignore error if not implemented */
-	if (scpi_info->is_legacy && ret == -EOPNOTSUPP)
+	if (info->is_legacy && ret == -EOPNOTSUPP)
 		return 0;
 
 	return ret;
@@ -913,13 +913,14 @@ static int scpi_probe(struct platform_device *pdev)
 	struct resource res;
 	struct device *dev = &pdev->dev;
 	struct device_node *np = dev->of_node;
+	struct scpi_drvinfo *scpi_drvinfo;
 
-	scpi_info = devm_kzalloc(dev, sizeof(*scpi_info), GFP_KERNEL);
-	if (!scpi_info)
+	scpi_drvinfo = devm_kzalloc(dev, sizeof(*scpi_drvinfo), GFP_KERNEL);
+	if (!scpi_drvinfo)
 		return -ENOMEM;
 
 	if (of_match_device(legacy_scpi_of_match, &pdev->dev))
-		scpi_info->is_legacy = true;
+		scpi_drvinfo->is_legacy = true;
 
 	count = of_count_phandle_with_args(np, "mboxes", "#mbox-cells");
 	if (count < 0) {
@@ -927,19 +928,19 @@ static int scpi_probe(struct platform_device *pdev)
 		return -ENODEV;
 	}
 
-	scpi_info->channels = devm_kcalloc(dev, count, sizeof(struct scpi_chan),
-					   GFP_KERNEL);
-	if (!scpi_info->channels)
+	scpi_drvinfo->channels =
+		devm_kcalloc(dev, count, sizeof(struct scpi_chan), GFP_KERNEL);
+	if (!scpi_drvinfo->channels)
 		return -ENOMEM;
 
-	ret = devm_add_action(dev, scpi_free_channels, scpi_info);
+	ret = devm_add_action(dev, scpi_free_channels, scpi_drvinfo);
 	if (ret)
 		return ret;
 
-	for (; scpi_info->num_chans < count; scpi_info->num_chans++) {
+	for (; scpi_drvinfo->num_chans < count; scpi_drvinfo->num_chans++) {
 		resource_size_t size;
-		int idx = scpi_info->num_chans;
-		struct scpi_chan *pchan = scpi_info->channels + idx;
+		int idx = scpi_drvinfo->num_chans;
+		struct scpi_chan *pchan = scpi_drvinfo->channels + idx;
 		struct mbox_client *cl = &pchan->cl;
 		struct device_node *shmem = of_parse_phandle(np, "shmem", idx);
 
@@ -986,45 +987,53 @@ static int scpi_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	scpi_info->commands = scpi_std_commands;
+	scpi_drvinfo->commands = scpi_std_commands;
 
-	platform_set_drvdata(pdev, scpi_info);
+	platform_set_drvdata(pdev, scpi_drvinfo);
 
-	if (scpi_info->is_legacy) {
+	if (scpi_drvinfo->is_legacy) {
 		/* Replace with legacy variants */
 		scpi_ops.clk_set_val = legacy_scpi_clk_set_val;
-		scpi_info->commands = scpi_legacy_commands;
+		scpi_drvinfo->commands = scpi_legacy_commands;
 
 		/* Fill priority bitmap */
 		for (idx = 0; idx < ARRAY_SIZE(legacy_hpriority_cmds); idx++)
 			set_bit(legacy_hpriority_cmds[idx],
-				scpi_info->cmd_priority);
+				scpi_drvinfo->cmd_priority);
 	}
 
-	ret = scpi_init_versions(scpi_info);
+	scpi_info = scpi_drvinfo;
+
+	ret = scpi_init_versions(scpi_drvinfo);
 	if (ret) {
 		dev_err(dev, "incorrect or no SCP firmware found\n");
+		scpi_info = NULL;
 		return ret;
 	}
 
-	if (scpi_info->is_legacy && !scpi_info->protocol_version &&
-	    !scpi_info->firmware_version)
+	if (scpi_drvinfo->is_legacy && !scpi_drvinfo->protocol_version &&
+	    !scpi_drvinfo->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),
+				   scpi_drvinfo->protocol_version),
 			 FIELD_GET(PROTO_REV_MINOR_MASK,
-				   scpi_info->protocol_version),
+				   scpi_drvinfo->protocol_version),
 			 FIELD_GET(FW_REV_MAJOR_MASK,
-				   scpi_info->firmware_version),
+				   scpi_drvinfo->firmware_version),
 			 FIELD_GET(FW_REV_MINOR_MASK,
-				   scpi_info->firmware_version),
+				   scpi_drvinfo->firmware_version),
 			 FIELD_GET(FW_REV_PATCH_MASK,
-				   scpi_info->firmware_version));
-	scpi_info->scpi_ops = &scpi_ops;
+				   scpi_drvinfo->firmware_version));
+
+	scpi_drvinfo->scpi_ops = &scpi_ops;
 
-	return devm_of_platform_populate(dev);
+	ret = devm_of_platform_populate(dev);
+	if (ret)
+		scpi_info = NULL;
+
+	return ret;
 }
 
 static const struct of_device_id scpi_of_match[] = {
diff --git a/drivers/firmware/qcom_scm-legacy.c b/drivers/firmware/qcom_scm-legacy.c
index 1829ba220576..9f918b9e6f8f 100644
--- a/drivers/firmware/qcom_scm-legacy.c
+++ b/drivers/firmware/qcom_scm-legacy.c
@@ -120,6 +120,9 @@ static void __scm_legacy_do(const struct arm_smccc_args *smc,
 /**
  * scm_legacy_call() - Sends a command to the SCM and waits for the command to
  * finish processing.
+ * @dev:	device
+ * @desc:	descriptor structure containing arguments and return values
+ * @res:        results from SMC call
  *
  * A note on cache maintenance:
  * Note that any buffers that are expected to be accessed by the secure world
@@ -211,6 +214,7 @@ out:
 /**
  * scm_legacy_call_atomic() - Send an atomic SCM command with up to 5 arguments
  * and 3 return values
+ * @unused: device, legacy argument, not used, can be NULL
  * @desc: SCM call descriptor containing arguments
  * @res:  SCM call return values
  *
diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c
index 3163660fa8e2..cdbfe54c8146 100644
--- a/drivers/firmware/qcom_scm.c
+++ b/drivers/firmware/qcom_scm.c
@@ -7,6 +7,7 @@
 #include <linux/cpumask.h>
 #include <linux/export.h>
 #include <linux/dma-mapping.h>
+#include <linux/interconnect.h>
 #include <linux/module.h>
 #include <linux/types.h>
 #include <linux/qcom_scm.h>
@@ -31,8 +32,13 @@ struct qcom_scm {
 	struct clk *core_clk;
 	struct clk *iface_clk;
 	struct clk *bus_clk;
+	struct icc_path *path;
 	struct reset_controller_dev reset;
 
+	/* control access to the interconnect path */
+	struct mutex scm_bw_lock;
+	int scm_vote_count;
+
 	u64 dload_mode_addr;
 };
 
@@ -99,6 +105,42 @@ static void qcom_scm_clk_disable(void)
 	clk_disable_unprepare(__scm->bus_clk);
 }
 
+static int qcom_scm_bw_enable(void)
+{
+	int ret = 0;
+
+	if (!__scm->path)
+		return 0;
+
+	if (IS_ERR(__scm->path))
+		return -EINVAL;
+
+	mutex_lock(&__scm->scm_bw_lock);
+	if (!__scm->scm_vote_count) {
+		ret = icc_set_bw(__scm->path, 0, UINT_MAX);
+		if (ret < 0) {
+			dev_err(__scm->dev, "failed to set bandwidth request\n");
+			goto err_bw;
+		}
+	}
+	__scm->scm_vote_count++;
+err_bw:
+	mutex_unlock(&__scm->scm_bw_lock);
+
+	return ret;
+}
+
+static void qcom_scm_bw_disable(void)
+{
+	if (IS_ERR_OR_NULL(__scm->path))
+		return;
+
+	mutex_lock(&__scm->scm_bw_lock);
+	if (__scm->scm_vote_count-- == 1)
+		icc_set_bw(__scm->path, 0, 0);
+	mutex_unlock(&__scm->scm_bw_lock);
+}
+
 enum qcom_scm_convention qcom_scm_convention = SMC_CONVENTION_UNKNOWN;
 static DEFINE_SPINLOCK(scm_query_lock);
 
@@ -444,10 +486,15 @@ int qcom_scm_pas_init_image(u32 peripheral, const void *metadata, size_t size,
 	if (ret)
 		goto out;
 
+	ret = qcom_scm_bw_enable();
+	if (ret)
+		return ret;
+
 	desc.args[1] = mdata_phys;
 
 	ret = qcom_scm_call(__scm->dev, &desc, &res);
 
+	qcom_scm_bw_disable();
 	qcom_scm_clk_disable();
 
 out:
@@ -507,7 +554,12 @@ int qcom_scm_pas_mem_setup(u32 peripheral, phys_addr_t addr, phys_addr_t size)
 	if (ret)
 		return ret;
 
+	ret = qcom_scm_bw_enable();
+	if (ret)
+		return ret;
+
 	ret = qcom_scm_call(__scm->dev, &desc, &res);
+	qcom_scm_bw_disable();
 	qcom_scm_clk_disable();
 
 	return ret ? : res.result[0];
@@ -537,7 +589,12 @@ int qcom_scm_pas_auth_and_reset(u32 peripheral)
 	if (ret)
 		return ret;
 
+	ret = qcom_scm_bw_enable();
+	if (ret)
+		return ret;
+
 	ret = qcom_scm_call(__scm->dev, &desc, &res);
+	qcom_scm_bw_disable();
 	qcom_scm_clk_disable();
 
 	return ret ? : res.result[0];
@@ -566,8 +623,13 @@ int qcom_scm_pas_shutdown(u32 peripheral)
 	if (ret)
 		return ret;
 
+	ret = qcom_scm_bw_enable();
+	if (ret)
+		return ret;
+
 	ret = qcom_scm_call(__scm->dev, &desc, &res);
 
+	qcom_scm_bw_disable();
 	qcom_scm_clk_disable();
 
 	return ret ? : res.result[0];
@@ -1277,8 +1339,15 @@ static int qcom_scm_probe(struct platform_device *pdev)
 	if (ret < 0)
 		return ret;
 
+	mutex_init(&scm->scm_bw_lock);
+
 	clks = (unsigned long)of_device_get_match_data(&pdev->dev);
 
+	scm->path = devm_of_icc_get(&pdev->dev, NULL);
+	if (IS_ERR(scm->path))
+		return dev_err_probe(&pdev->dev, PTR_ERR(scm->path),
+				     "failed to acquire interconnect path\n");
+
 	scm->core_clk = devm_clk_get(&pdev->dev, "core");
 	if (IS_ERR(scm->core_clk)) {
 		if (PTR_ERR(scm->core_clk) == -EPROBE_DEFER)
@@ -1337,7 +1406,7 @@ static int qcom_scm_probe(struct platform_device *pdev)
 
 	/*
 	 * If requested enable "download mode", from this point on warmboot
-	 * will cause the the boot stages to enter download mode, unless
+	 * will cause the boot stages to enter download mode, unless
 	 * disabled below by a clean shutdown/reboot.
 	 */
 	if (download_mode)
diff --git a/drivers/firmware/tegra/bpmp-debugfs.c b/drivers/firmware/tegra/bpmp-debugfs.c
index fd89899aeeed..0c440afd5224 100644
--- a/drivers/firmware/tegra/bpmp-debugfs.c
+++ b/drivers/firmware/tegra/bpmp-debugfs.c
@@ -474,7 +474,7 @@ static int bpmp_populate_debugfs_inband(struct tegra_bpmp *bpmp,
 			mode |= attrs & DEBUGFS_S_IWUSR ? 0200 : 0;
 			dentry = debugfs_create_file(name, mode, parent, bpmp,
 						     &bpmp_debug_fops);
-			if (!dentry) {
+			if (IS_ERR(dentry)) {
 				err = -ENOMEM;
 				goto out;
 			}
@@ -725,7 +725,7 @@ static int bpmp_populate_dir(struct tegra_bpmp *bpmp, struct seqbuf *seqbuf,
 
 		if (t & DEBUGFS_S_ISDIR) {
 			dentry = debugfs_create_dir(name, parent);
-			if (!dentry)
+			if (IS_ERR(dentry))
 				return -ENOMEM;
 			err = bpmp_populate_dir(bpmp, seqbuf, dentry, depth+1);
 			if (err < 0)
@@ -738,7 +738,7 @@ static int bpmp_populate_dir(struct tegra_bpmp *bpmp, struct seqbuf *seqbuf,
 			dentry = debugfs_create_file(name, mode,
 						     parent, bpmp,
 						     &debugfs_fops);
-			if (!dentry)
+			if (IS_ERR(dentry))
 				return -ENOMEM;
 		}
 	}
@@ -788,11 +788,11 @@ int tegra_bpmp_init_debugfs(struct tegra_bpmp *bpmp)
 		return 0;
 
 	root = debugfs_create_dir("bpmp", NULL);
-	if (!root)
+	if (IS_ERR(root))
 		return -ENOMEM;
 
 	bpmp->debugfs_mirror = debugfs_create_dir("debug", root);
-	if (!bpmp->debugfs_mirror) {
+	if (IS_ERR(bpmp->debugfs_mirror)) {
 		err = -ENOMEM;
 		goto out;
 	}
diff --git a/drivers/firmware/tegra/bpmp.c b/drivers/firmware/tegra/bpmp.c
index 5654c5e9862b..037db21de510 100644
--- a/drivers/firmware/tegra/bpmp.c
+++ b/drivers/firmware/tegra/bpmp.c
@@ -201,7 +201,7 @@ static ssize_t __tegra_bpmp_channel_read(struct tegra_bpmp_channel *channel,
 	int err;
 
 	if (data && size > 0)
-		memcpy(data, channel->ib->data, size);
+		memcpy_fromio(data, channel->ib->data, size);
 
 	err = tegra_bpmp_ack_response(channel);
 	if (err < 0)
@@ -245,7 +245,7 @@ static ssize_t __tegra_bpmp_channel_write(struct tegra_bpmp_channel *channel,
 	channel->ob->flags = flags;
 
 	if (data && size > 0)
-		memcpy(channel->ob->data, data, size);
+		memcpy_toio(channel->ob->data, data, size);
 
 	return tegra_bpmp_post_request(channel);
 }
@@ -420,7 +420,7 @@ void tegra_bpmp_mrq_return(struct tegra_bpmp_channel *channel, int code,
 	channel->ob->code = code;
 
 	if (data && size > 0)
-		memcpy(channel->ob->data, data, size);
+		memcpy_toio(channel->ob->data, data, size);
 
 	err = tegra_bpmp_post_response(channel);
 	if (WARN_ON(err < 0))