Merge tag 'arm-ffa-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux into arm/drivers

Arm Firmware Framework for ARMv8-A(FFA) interface driver

The Arm FFA specification describes a software architecture to
leverages the virtualization extension to isolate software images
provided by an ecosystem of vendors from each other and describes
interfaces that standardize communication between the various software
images including communication between images in the Secure world and
Normal world. Any Hypervisor could use the FFA interfaces to enable
communication between VMs it manages.

The Hypervisor a.k.a Partition managers in FFA terminology can assign
system resources(Memory regions, Devices, CPU cycles) to the partitions
and manage isolation amongst them.

This is the initial and minimal support for the FFA interface to enable
communication between secure partitions and the normal world OS.

* tag 'arm-ffa-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux:
  firmware: arm_ffa: Add support for MEM_* interfaces
  firmware: arm_ffa: Setup in-kernel users of FFA partitions
  firmware: arm_ffa: Add support for SMCCC as transport to FFA driver
  firmware: arm_ffa: Add initial Arm FFA driver support
  firmware: arm_ffa: Add initial FFA bus support for device enumeration
  arm64: smccc: Add support for SMCCCv1.2 extended input/output registers

Link: https://lore.kernel.org/r/20210601095838.GA838783@bogus
Signed-off-by: Olof Johansson <olof@lixom.net>

8 files changed, 1040 insertions, 0 deletions

diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig
index a9c613c32282..1db738d5b301 100644
--- a/drivers/firmware/Kconfig
+++ b/drivers/firmware/Kconfig
@@ -296,6 +296,7 @@ config TURRIS_MOX_RWTM
 	  other manufacturing data and also utilize the Entropy Bit Generator
 	  for hardware random number generation.
 
+source "drivers/firmware/arm_ffa/Kconfig"
 source "drivers/firmware/broadcom/Kconfig"
 source "drivers/firmware/google/Kconfig"
 source "drivers/firmware/efi/Kconfig"
diff --git a/drivers/firmware/Makefile b/drivers/firmware/Makefile
index 5e013b6a3692..546ac8e7f6d0 100644
--- a/drivers/firmware/Makefile
+++ b/drivers/firmware/Makefile
@@ -22,6 +22,7 @@ obj-$(CONFIG_TI_SCI_PROTOCOL)	+= ti_sci.o
 obj-$(CONFIG_TRUSTED_FOUNDATIONS) += trusted_foundations.o
 obj-$(CONFIG_TURRIS_MOX_RWTM)	+= turris-mox-rwtm.o
 
+obj-y				+= arm_ffa/
 obj-y				+= arm_scmi/
 obj-y				+= broadcom/
 obj-y				+= meson/
diff --git a/drivers/firmware/arm_ffa/Kconfig b/drivers/firmware/arm_ffa/Kconfig
new file mode 100644
index 000000000000..5e3ae5cf82e8
--- /dev/null
+++ b/drivers/firmware/arm_ffa/Kconfig
@@ -0,0 +1,21 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config ARM_FFA_TRANSPORT
+	tristate "Arm Firmware Framework for Armv8-A"
+	depends on OF
+	depends on ARM64
+	default n
+	help
+	  This Firmware Framework(FF) for Arm A-profile processors describes
+	  interfaces that standardize communication between the various
+	  software images which includes communication between images in
+	  the Secure world and Normal world. It also leverages the
+	  virtualization extension to isolate software images provided
+	  by an ecosystem of vendors from each other.
+
+	  This driver provides interface for all the client drivers making
+	  use of the features offered by ARM FF-A.
+
+config ARM_FFA_SMCCC
+	bool
+	default ARM_FFA_TRANSPORT
+	depends on ARM64 && HAVE_ARM_SMCCC_DISCOVERY
diff --git a/drivers/firmware/arm_ffa/Makefile b/drivers/firmware/arm_ffa/Makefile
new file mode 100644
index 000000000000..9d9f37523200
--- /dev/null
+++ b/drivers/firmware/arm_ffa/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0-only
+ffa-bus-y = bus.o
+ffa-driver-y = driver.o
+ffa-transport-$(CONFIG_ARM_FFA_SMCCC) += smccc.o
+ffa-module-objs := $(ffa-bus-y) $(ffa-driver-y) $(ffa-transport-y)
+obj-$(CONFIG_ARM_FFA_TRANSPORT) = ffa-module.o
diff --git a/drivers/firmware/arm_ffa/bus.c b/drivers/firmware/arm_ffa/bus.c
new file mode 100644
index 000000000000..83166e02b191
--- /dev/null
+++ b/drivers/firmware/arm_ffa/bus.c
@@ -0,0 +1,210 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2021 ARM Ltd.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/arm_ffa.h>
+#include <linux/device.h>
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#include "common.h"
+
+static int ffa_device_match(struct device *dev, struct device_driver *drv)
+{
+	const struct ffa_device_id *id_table;
+	struct ffa_device *ffa_dev;
+
+	id_table = to_ffa_driver(drv)->id_table;
+	ffa_dev = to_ffa_dev(dev);
+
+	while (!uuid_is_null(&id_table->uuid)) {
+		/*
+		 * FF-A v1.0 doesn't provide discovery of UUIDs, just the
+		 * partition IDs, so fetch the partitions IDs for this
+		 * id_table UUID and assign the UUID to the device if the
+		 * partition ID matches
+		 */
+		if (uuid_is_null(&ffa_dev->uuid))
+			ffa_device_match_uuid(ffa_dev, &id_table->uuid);
+
+		if (uuid_equal(&ffa_dev->uuid, &id_table->uuid))
+			return 1;
+		id_table++;
+	}
+
+	return 0;
+}
+
+static int ffa_device_probe(struct device *dev)
+{
+	struct ffa_driver *ffa_drv = to_ffa_driver(dev->driver);
+	struct ffa_device *ffa_dev = to_ffa_dev(dev);
+
+	if (!ffa_device_match(dev, dev->driver))
+		return -ENODEV;
+
+	return ffa_drv->probe(ffa_dev);
+}
+
+static int ffa_device_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	struct ffa_device *ffa_dev = to_ffa_dev(dev);
+
+	return add_uevent_var(env, "MODALIAS=arm_ffa:%04x:%pUb",
+			      ffa_dev->vm_id, &ffa_dev->uuid);
+}
+
+static ssize_t partition_id_show(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	struct ffa_device *ffa_dev = to_ffa_dev(dev);
+
+	return sprintf(buf, "0x%04x\n", ffa_dev->vm_id);
+}
+static DEVICE_ATTR_RO(partition_id);
+
+static ssize_t uuid_show(struct device *dev, struct device_attribute *attr,
+			 char *buf)
+{
+	struct ffa_device *ffa_dev = to_ffa_dev(dev);
+
+	return sprintf(buf, "%pUb\n", &ffa_dev->uuid);
+}
+static DEVICE_ATTR_RO(uuid);
+
+static struct attribute *ffa_device_attributes_attrs[] = {
+	&dev_attr_partition_id.attr,
+	&dev_attr_uuid.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(ffa_device_attributes);
+
+struct bus_type ffa_bus_type = {
+	.name		= "arm_ffa",
+	.match		= ffa_device_match,
+	.probe		= ffa_device_probe,
+	.uevent		= ffa_device_uevent,
+	.dev_groups	= ffa_device_attributes_groups,
+};
+EXPORT_SYMBOL_GPL(ffa_bus_type);
+
+int ffa_driver_register(struct ffa_driver *driver, struct module *owner,
+			const char *mod_name)
+{
+	int ret;
+
+	driver->driver.bus = &ffa_bus_type;
+	driver->driver.name = driver->name;
+	driver->driver.owner = owner;
+	driver->driver.mod_name = mod_name;
+
+	ret = driver_register(&driver->driver);
+	if (!ret)
+		pr_debug("registered new ffa driver %s\n", driver->name);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(ffa_driver_register);
+
+void ffa_driver_unregister(struct ffa_driver *driver)
+{
+	driver_unregister(&driver->driver);
+}
+EXPORT_SYMBOL_GPL(ffa_driver_unregister);
+
+static void ffa_release_device(struct device *dev)
+{
+	struct ffa_device *ffa_dev = to_ffa_dev(dev);
+
+	kfree(ffa_dev);
+}
+
+static int __ffa_devices_unregister(struct device *dev, void *data)
+{
+	ffa_release_device(dev);
+
+	return 0;
+}
+
+static void ffa_devices_unregister(void)
+{
+	bus_for_each_dev(&ffa_bus_type, NULL, NULL,
+			 __ffa_devices_unregister);
+}
+
+bool ffa_device_is_valid(struct ffa_device *ffa_dev)
+{
+	bool valid = false;
+	struct device *dev = NULL;
+	struct ffa_device *tmp_dev;
+
+	do {
+		dev = bus_find_next_device(&ffa_bus_type, dev);
+		tmp_dev = to_ffa_dev(dev);
+		if (tmp_dev == ffa_dev) {
+			valid = true;
+			break;
+		}
+		put_device(dev);
+	} while (dev);
+
+	put_device(dev);
+
+	return valid;
+}
+
+struct ffa_device *ffa_device_register(const uuid_t *uuid, int vm_id)
+{
+	int ret;
+	struct device *dev;
+	struct ffa_device *ffa_dev;
+
+	ffa_dev = kzalloc(sizeof(*ffa_dev), GFP_KERNEL);
+	if (!ffa_dev)
+		return NULL;
+
+	dev = &ffa_dev->dev;
+	dev->bus = &ffa_bus_type;
+	dev->release = ffa_release_device;
+	dev_set_name(&ffa_dev->dev, "arm-ffa-%04x", vm_id);
+
+	ffa_dev->vm_id = vm_id;
+	uuid_copy(&ffa_dev->uuid, uuid);
+
+	ret = device_register(&ffa_dev->dev);
+	if (ret) {
+		dev_err(dev, "unable to register device %s err=%d\n",
+			dev_name(dev), ret);
+		put_device(dev);
+		return NULL;
+	}
+
+	return ffa_dev;
+}
+EXPORT_SYMBOL_GPL(ffa_device_register);
+
+void ffa_device_unregister(struct ffa_device *ffa_dev)
+{
+	if (!ffa_dev)
+		return;
+
+	device_unregister(&ffa_dev->dev);
+}
+EXPORT_SYMBOL_GPL(ffa_device_unregister);
+
+int arm_ffa_bus_init(void)
+{
+	return bus_register(&ffa_bus_type);
+}
+
+void arm_ffa_bus_exit(void)
+{
+	ffa_devices_unregister();
+	bus_unregister(&ffa_bus_type);
+}
diff --git a/drivers/firmware/arm_ffa/common.h b/drivers/firmware/arm_ffa/common.h
new file mode 100644
index 000000000000..d6eccf1fd3f6
--- /dev/null
+++ b/drivers/firmware/arm_ffa/common.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2021 ARM Ltd.
+ */
+
+#ifndef _FFA_COMMON_H
+#define _FFA_COMMON_H
+
+#include <linux/arm_ffa.h>
+#include <linux/arm-smccc.h>
+#include <linux/err.h>
+
+typedef struct arm_smccc_1_2_regs ffa_value_t;
+
+typedef void (ffa_fn)(ffa_value_t, ffa_value_t *);
+
+int arm_ffa_bus_init(void);
+void arm_ffa_bus_exit(void);
+bool ffa_device_is_valid(struct ffa_device *ffa_dev);
+void ffa_device_match_uuid(struct ffa_device *ffa_dev, const uuid_t *uuid);
+
+#ifdef CONFIG_ARM_FFA_SMCCC
+int __init ffa_transport_init(ffa_fn **invoke_ffa_fn);
+#else
+static inline int __init ffa_transport_init(ffa_fn **invoke_ffa_fn)
+{
+	return -EOPNOTSUPP;
+}
+#endif
+
+#endif /* _FFA_COMMON_H */
diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c
new file mode 100644
index 000000000000..b1edb4b2e94a
--- /dev/null
+++ b/drivers/firmware/arm_ffa/driver.c
@@ -0,0 +1,731 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Arm Firmware Framework for ARMv8-A(FFA) interface driver
+ *
+ * The Arm FFA specification[1] describes a software architecture to
+ * leverages the virtualization extension to isolate software images
+ * provided by an ecosystem of vendors from each other and describes
+ * interfaces that standardize communication between the various software
+ * images including communication between images in the Secure world and
+ * Normal world. Any Hypervisor could use the FFA interfaces to enable
+ * communication between VMs it manages.
+ *
+ * The Hypervisor a.k.a Partition managers in FFA terminology can assign
+ * system resources(Memory regions, Devices, CPU cycles) to the partitions
+ * and manage isolation amongst them.
+ *
+ * [1] https://developer.arm.com/docs/den0077/latest
+ *
+ * Copyright (C) 2021 ARM Ltd.
+ */
+
+#define DRIVER_NAME "ARM FF-A"
+#define pr_fmt(fmt) DRIVER_NAME ": " fmt
+
+#include <linux/arm_ffa.h>
+#include <linux/bitfield.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include <linux/uuid.h>
+
+#include "common.h"
+
+#define FFA_DRIVER_VERSION	FFA_VERSION_1_0
+
+#define FFA_SMC(calling_convention, func_num)				\
+	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, (calling_convention),	\
+			   ARM_SMCCC_OWNER_STANDARD, (func_num))
+
+#define FFA_SMC_32(func_num)	FFA_SMC(ARM_SMCCC_SMC_32, (func_num))
+#define FFA_SMC_64(func_num)	FFA_SMC(ARM_SMCCC_SMC_64, (func_num))
+
+#define FFA_ERROR			FFA_SMC_32(0x60)
+#define FFA_SUCCESS			FFA_SMC_32(0x61)
+#define FFA_INTERRUPT			FFA_SMC_32(0x62)
+#define FFA_VERSION			FFA_SMC_32(0x63)
+#define FFA_FEATURES			FFA_SMC_32(0x64)
+#define FFA_RX_RELEASE			FFA_SMC_32(0x65)
+#define FFA_RXTX_MAP			FFA_SMC_32(0x66)
+#define FFA_FN64_RXTX_MAP		FFA_SMC_64(0x66)
+#define FFA_RXTX_UNMAP			FFA_SMC_32(0x67)
+#define FFA_PARTITION_INFO_GET		FFA_SMC_32(0x68)
+#define FFA_ID_GET			FFA_SMC_32(0x69)
+#define FFA_MSG_POLL			FFA_SMC_32(0x6A)
+#define FFA_MSG_WAIT			FFA_SMC_32(0x6B)
+#define FFA_YIELD			FFA_SMC_32(0x6C)
+#define FFA_RUN				FFA_SMC_32(0x6D)
+#define FFA_MSG_SEND			FFA_SMC_32(0x6E)
+#define FFA_MSG_SEND_DIRECT_REQ		FFA_SMC_32(0x6F)
+#define FFA_FN64_MSG_SEND_DIRECT_REQ	FFA_SMC_64(0x6F)
+#define FFA_MSG_SEND_DIRECT_RESP	FFA_SMC_32(0x70)
+#define FFA_FN64_MSG_SEND_DIRECT_RESP	FFA_SMC_64(0x70)
+#define FFA_MEM_DONATE			FFA_SMC_32(0x71)
+#define FFA_FN64_MEM_DONATE		FFA_SMC_64(0x71)
+#define FFA_MEM_LEND			FFA_SMC_32(0x72)
+#define FFA_FN64_MEM_LEND		FFA_SMC_64(0x72)
+#define FFA_MEM_SHARE			FFA_SMC_32(0x73)
+#define FFA_FN64_MEM_SHARE		FFA_SMC_64(0x73)
+#define FFA_MEM_RETRIEVE_REQ		FFA_SMC_32(0x74)
+#define FFA_FN64_MEM_RETRIEVE_REQ	FFA_SMC_64(0x74)
+#define FFA_MEM_RETRIEVE_RESP		FFA_SMC_32(0x75)
+#define FFA_MEM_RELINQUISH		FFA_SMC_32(0x76)
+#define FFA_MEM_RECLAIM			FFA_SMC_32(0x77)
+#define FFA_MEM_OP_PAUSE		FFA_SMC_32(0x78)
+#define FFA_MEM_OP_RESUME		FFA_SMC_32(0x79)
+#define FFA_MEM_FRAG_RX			FFA_SMC_32(0x7A)
+#define FFA_MEM_FRAG_TX			FFA_SMC_32(0x7B)
+#define FFA_NORMAL_WORLD_RESUME		FFA_SMC_32(0x7C)
+
+/*
+ * For some calls it is necessary to use SMC64 to pass or return 64-bit values.
+ * For such calls FFA_FN_NATIVE(name) will choose the appropriate
+ * (native-width) function ID.
+ */
+#ifdef CONFIG_64BIT
+#define FFA_FN_NATIVE(name)	FFA_FN64_##name
+#else
+#define FFA_FN_NATIVE(name)	FFA_##name
+#endif
+
+/* FFA error codes. */
+#define FFA_RET_SUCCESS            (0)
+#define FFA_RET_NOT_SUPPORTED      (-1)
+#define FFA_RET_INVALID_PARAMETERS (-2)
+#define FFA_RET_NO_MEMORY          (-3)
+#define FFA_RET_BUSY               (-4)
+#define FFA_RET_INTERRUPTED        (-5)
+#define FFA_RET_DENIED             (-6)
+#define FFA_RET_RETRY              (-7)
+#define FFA_RET_ABORTED            (-8)
+
+#define MAJOR_VERSION_MASK	GENMASK(30, 16)
+#define MINOR_VERSION_MASK	GENMASK(15, 0)
+#define MAJOR_VERSION(x)	((u16)(FIELD_GET(MAJOR_VERSION_MASK, (x))))
+#define MINOR_VERSION(x)	((u16)(FIELD_GET(MINOR_VERSION_MASK, (x))))
+#define PACK_VERSION_INFO(major, minor)			\
+	(FIELD_PREP(MAJOR_VERSION_MASK, (major)) |	\
+	 FIELD_PREP(MINOR_VERSION_MASK, (minor)))
+#define FFA_VERSION_1_0		PACK_VERSION_INFO(1, 0)
+#define FFA_MIN_VERSION		FFA_VERSION_1_0
+
+#define SENDER_ID_MASK		GENMASK(31, 16)
+#define RECEIVER_ID_MASK	GENMASK(15, 0)
+#define SENDER_ID(x)		((u16)(FIELD_GET(SENDER_ID_MASK, (x))))
+#define RECEIVER_ID(x)		((u16)(FIELD_GET(RECEIVER_ID_MASK, (x))))
+#define PACK_TARGET_INFO(s, r)		\
+	(FIELD_PREP(SENDER_ID_MASK, (s)) | FIELD_PREP(RECEIVER_ID_MASK, (r)))
+
+/**
+ * FF-A specification mentions explicitly about '4K pages'. This should
+ * not be confused with the kernel PAGE_SIZE, which is the translation
+ * granule kernel is configured and may be one among 4K, 16K and 64K.
+ */
+#define FFA_PAGE_SIZE		SZ_4K
+/*
+ * Keeping RX TX buffer size as 4K for now
+ * 64K may be preferred to keep it min a page in 64K PAGE_SIZE config
+ */
+#define RXTX_BUFFER_SIZE	SZ_4K
+
+static ffa_fn *invoke_ffa_fn;
+
+static const int ffa_linux_errmap[] = {
+	/* better than switch case as long as return value is continuous */
+	0,		/* FFA_RET_SUCCESS */
+	-EOPNOTSUPP,	/* FFA_RET_NOT_SUPPORTED */
+	-EINVAL,	/* FFA_RET_INVALID_PARAMETERS */
+	-ENOMEM,	/* FFA_RET_NO_MEMORY */
+	-EBUSY,		/* FFA_RET_BUSY */
+	-EINTR,		/* FFA_RET_INTERRUPTED */
+	-EACCES,	/* FFA_RET_DENIED */
+	-EAGAIN,	/* FFA_RET_RETRY */
+	-ECANCELED,	/* FFA_RET_ABORTED */
+};
+
+static inline int ffa_to_linux_errno(int errno)
+{
+	if (errno < FFA_RET_SUCCESS && errno >= -ARRAY_SIZE(ffa_linux_errmap))
+		return ffa_linux_errmap[-errno];
+	return -EINVAL;
+}
+
+struct ffa_drv_info {
+	u32 version;
+	u16 vm_id;
+	struct mutex rx_lock; /* lock to protect Rx buffer */
+	struct mutex tx_lock; /* lock to protect Tx buffer */
+	void *rx_buffer;
+	void *tx_buffer;
+};
+
+static struct ffa_drv_info *drv_info;
+
+static int ffa_version_check(u32 *version)
+{
+	ffa_value_t ver;
+
+	invoke_ffa_fn((ffa_value_t){
+		      .a0 = FFA_VERSION, .a1 = FFA_DRIVER_VERSION,
+		      }, &ver);
+
+	if (ver.a0 == FFA_RET_NOT_SUPPORTED) {
+		pr_info("FFA_VERSION returned not supported\n");
+		return -EOPNOTSUPP;
+	}
+
+	if (ver.a0 < FFA_MIN_VERSION || ver.a0 > FFA_DRIVER_VERSION) {
+		pr_err("Incompatible version %d.%d found\n",
+		       MAJOR_VERSION(ver.a0), MINOR_VERSION(ver.a0));
+		return -EINVAL;
+	}
+
+	*version = ver.a0;
+	pr_info("Version %d.%d found\n", MAJOR_VERSION(ver.a0),
+		MINOR_VERSION(ver.a0));
+	return 0;
+}
+
+static int ffa_rx_release(void)
+{
+	ffa_value_t ret;
+
+	invoke_ffa_fn((ffa_value_t){
+		      .a0 = FFA_RX_RELEASE,
+		      }, &ret);
+
+	if (ret.a0 == FFA_ERROR)
+		return ffa_to_linux_errno((int)ret.a2);
+
+	/* check for ret.a0 == FFA_RX_RELEASE ? */
+
+	return 0;
+}
+
+static int ffa_rxtx_map(phys_addr_t tx_buf, phys_addr_t rx_buf, u32 pg_cnt)
+{
+	ffa_value_t ret;
+
+	invoke_ffa_fn((ffa_value_t){
+		      .a0 = FFA_FN_NATIVE(RXTX_MAP),
+		      .a1 = tx_buf, .a2 = rx_buf, .a3 = pg_cnt,
+		      }, &ret);
+
+	if (ret.a0 == FFA_ERROR)
+		return ffa_to_linux_errno((int)ret.a2);
+
+	return 0;
+}
+
+static int ffa_rxtx_unmap(u16 vm_id)
+{
+	ffa_value_t ret;
+
+	invoke_ffa_fn((ffa_value_t){
+		      .a0 = FFA_RXTX_UNMAP, .a1 = PACK_TARGET_INFO(vm_id, 0),
+		      }, &ret);
+
+	if (ret.a0 == FFA_ERROR)
+		return ffa_to_linux_errno((int)ret.a2);
+
+	return 0;
+}
+
+/* buffer must be sizeof(struct ffa_partition_info) * num_partitions */
+static int
+__ffa_partition_info_get(u32 uuid0, u32 uuid1, u32 uuid2, u32 uuid3,
+			 struct ffa_partition_info *buffer, int num_partitions)
+{
+	int count;
+	ffa_value_t partition_info;
+
+	mutex_lock(&drv_info->rx_lock);
+	invoke_ffa_fn((ffa_value_t){
+		      .a0 = FFA_PARTITION_INFO_GET,
+		      .a1 = uuid0, .a2 = uuid1, .a3 = uuid2, .a4 = uuid3,
+		      }, &partition_info);
+
+	if (partition_info.a0 == FFA_ERROR) {
+		mutex_unlock(&drv_info->rx_lock);
+		return ffa_to_linux_errno((int)partition_info.a2);
+	}
+
+	count = partition_info.a2;
+
+	if (buffer && count <= num_partitions)
+		memcpy(buffer, drv_info->rx_buffer, sizeof(*buffer) * count);
+
+	ffa_rx_release();
+
+	mutex_unlock(&drv_info->rx_lock);
+
+	return count;
+}
+
+/* buffer is allocated and caller must free the same if returned count > 0 */
+static int
+ffa_partition_probe(const uuid_t *uuid, struct ffa_partition_info **buffer)
+{
+	int count;
+	u32 uuid0_4[4];
+	struct ffa_partition_info *pbuf;
+
+	export_uuid((u8 *)uuid0_4, uuid);
+	count = __ffa_partition_info_get(uuid0_4[0], uuid0_4[1], uuid0_4[2],
+					 uuid0_4[3], NULL, 0);
+	if (count <= 0)
+		return count;
+
+	pbuf = kcalloc(count, sizeof(*pbuf), GFP_KERNEL);
+	if (!pbuf)
+		return -ENOMEM;
+
+	count = __ffa_partition_info_get(uuid0_4[0], uuid0_4[1], uuid0_4[2],
+					 uuid0_4[3], pbuf, count);
+	if (count <= 0)
+		kfree(pbuf);
+	else
+		*buffer = pbuf;
+
+	return count;
+}
+
+#define VM_ID_MASK	GENMASK(15, 0)
+static int ffa_id_get(u16 *vm_id)
+{
+	ffa_value_t id;
+
+	invoke_ffa_fn((ffa_value_t){
+		      .a0 = FFA_ID_GET,
+		      }, &id);
+
+	if (id.a0 == FFA_ERROR)
+		return ffa_to_linux_errno((int)id.a2);
+
+	*vm_id = FIELD_GET(VM_ID_MASK, (id.a2));
+
+	return 0;
+}
+
+static int ffa_msg_send_direct_req(u16 src_id, u16 dst_id, bool mode_32bit,
+				   struct ffa_send_direct_data *data)
+{
+	u32 req_id, resp_id, src_dst_ids = PACK_TARGET_INFO(src_id, dst_id);
+	ffa_value_t ret;
+
+	if (mode_32bit) {
+		req_id = FFA_MSG_SEND_DIRECT_REQ;
+		resp_id = FFA_MSG_SEND_DIRECT_RESP;
+	} else {
+		req_id = FFA_FN_NATIVE(MSG_SEND_DIRECT_REQ);
+		resp_id = FFA_FN_NATIVE(MSG_SEND_DIRECT_RESP);
+	}
+
+	invoke_ffa_fn((ffa_value_t){
+		      .a0 = req_id, .a1 = src_dst_ids, .a2 = 0,
+		      .a3 = data->data0, .a4 = data->data1, .a5 = data->data2,
+		      .a6 = data->data3, .a7 = data->data4,
+		      }, &ret);
+
+	while (ret.a0 == FFA_INTERRUPT)
+		invoke_ffa_fn((ffa_value_t){
+			      .a0 = FFA_RUN, .a1 = ret.a1,
+			      }, &ret);
+
+	if (ret.a0 == FFA_ERROR)
+		return ffa_to_linux_errno((int)ret.a2);
+
+	if (ret.a0 == resp_id) {
+		data->data0 = ret.a3;
+		data->data1 = ret.a4;
+		data->data2 = ret.a5;
+		data->data3 = ret.a6;
+		data->data4 = ret.a7;
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static int ffa_mem_first_frag(u32 func_id, phys_addr_t buf, u32 buf_sz,
+			      u32 frag_len, u32 len, u64 *handle)
+{
+	ffa_value_t ret;
+
+	invoke_ffa_fn((ffa_value_t){
+		      .a0 = func_id, .a1 = len, .a2 = frag_len,
+		      .a3 = buf, .a4 = buf_sz,
+		      }, &ret);
+
+	while (ret.a0 == FFA_MEM_OP_PAUSE)
+		invoke_ffa_fn((ffa_value_t){
+			      .a0 = FFA_MEM_OP_RESUME,
+			      .a1 = ret.a1, .a2 = ret.a2,
+			      }, &ret);
+
+	if (ret.a0 == FFA_ERROR)
+		return ffa_to_linux_errno((int)ret.a2);
+
+	if (ret.a0 != FFA_SUCCESS)
+		return -EOPNOTSUPP;
+
+	if (handle)
+		*handle = PACK_HANDLE(ret.a2, ret.a3);
+
+	return frag_len;
+}
+
+static int ffa_mem_next_frag(u64 handle, u32 frag_len)
+{
+	ffa_value_t ret;
+
+	invoke_ffa_fn((ffa_value_t){
+		      .a0 = FFA_MEM_FRAG_TX,
+		      .a1 = HANDLE_LOW(handle), .a2 = HANDLE_HIGH(handle),
+		      .a3 = frag_len,
+		      }, &ret);
+
+	while (ret.a0 == FFA_MEM_OP_PAUSE)
+		invoke_ffa_fn((ffa_value_t){
+			      .a0 = FFA_MEM_OP_RESUME,
+			      .a1 = ret.a1, .a2 = ret.a2,
+			      }, &ret);
+
+	if (ret.a0 == FFA_ERROR)
+		return ffa_to_linux_errno((int)ret.a2);
+
+	if (ret.a0 != FFA_MEM_FRAG_RX)
+		return -EOPNOTSUPP;
+
+	return ret.a3;
+}
+
+static int
+ffa_transmit_fragment(u32 func_id, phys_addr_t buf, u32 buf_sz, u32 frag_len,
+		      u32 len, u64 *handle, bool first)
+{
+	if (!first)
+		return ffa_mem_next_frag(*handle, frag_len);
+
+	return ffa_mem_first_frag(func_id, buf, buf_sz, frag_len, len, handle);
+}
+
+static u32 ffa_get_num_pages_sg(struct scatterlist *sg)
+{
+	u32 num_pages = 0;
+
+	do {
+		num_pages += sg->length / FFA_PAGE_SIZE;
+	} while ((sg = sg_next(sg)));
+
+	return num_pages;
+}
+
+static int
+ffa_setup_and_transmit(u32 func_id, void *buffer, u32 max_fragsize,
+		       struct ffa_mem_ops_args *args)
+{
+	int rc = 0;
+	bool first = true;
+	phys_addr_t addr = 0;
+	struct ffa_composite_mem_region *composite;
+	struct ffa_mem_region_addr_range *constituents;
+	struct ffa_mem_region_attributes *ep_mem_access;
+	struct ffa_mem_region *mem_region = buffer;
+	u32 idx, frag_len, length, buf_sz = 0, num_entries = sg_nents(args->sg);
+
+	mem_region->tag = args->tag;
+	mem_region->flags = args->flags;
+	mem_region->sender_id = drv_info->vm_id;
+	mem_region->attributes = FFA_MEM_NORMAL | FFA_MEM_WRITE_BACK |
+				 FFA_MEM_INNER_SHAREABLE;
+	ep_mem_access = &mem_region->ep_mem_access[0];
+
+	for (idx = 0; idx < args->nattrs; idx++, ep_mem_access++) {
+		ep_mem_access->receiver = args->attrs[idx].receiver;
+		ep_mem_access->attrs = args->attrs[idx].attrs;
+		ep_mem_access->composite_off = COMPOSITE_OFFSET(args->nattrs);
+	}
+	mem_region->ep_count = args->nattrs;
+
+	composite = buffer + COMPOSITE_OFFSET(args->nattrs);
+	composite->total_pg_cnt = ffa_get_num_pages_sg(args->sg);
+	composite->addr_range_cnt = num_entries;
+
+	length = COMPOSITE_CONSTITUENTS_OFFSET(args->nattrs, num_entries);
+	frag_len = COMPOSITE_CONSTITUENTS_OFFSET(args->nattrs, 0);
+	if (frag_len > max_fragsize)
+		return -ENXIO;
+
+	if (!args->use_txbuf) {
+		addr = virt_to_phys(buffer);
+		buf_sz = max_fragsize / FFA_PAGE_SIZE;
+	}
+
+	constituents = buffer + frag_len;
+	idx = 0;
+	do {
+		if (frag_len == max_fragsize) {
+			rc = ffa_transmit_fragment(func_id, addr, buf_sz,
+						   frag_len, length,
+						   &args->g_handle, first);
+			if (rc < 0)
+				return -ENXIO;
+
+			first = false;
+			idx = 0;
+			frag_len = 0;
+			constituents = buffer;
+		}
+
+		if ((void *)constituents - buffer > max_fragsize) {
+			pr_err("Memory Region Fragment > Tx Buffer size\n");
+			return -EFAULT;
+		}
+
+		constituents->address = sg_phys(args->sg);
+		constituents->pg_cnt = args->sg->length / FFA_PAGE_SIZE;
+		constituents++;
+		frag_len += sizeof(struct ffa_mem_region_addr_range);
+	} while ((args->sg = sg_next(args->sg)));
+
+	return ffa_transmit_fragment(func_id, addr, buf_sz, frag_len,
+				     length, &args->g_handle, first);
+}
+
+static int ffa_memory_ops(u32 func_id, struct ffa_mem_ops_args *args)
+{
+	int ret;
+	void *buffer;
+
+	if (!args->use_txbuf) {
+		buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL);
+		if (!buffer)
+			return -ENOMEM;
+	} else {
+		buffer = drv_info->tx_buffer;
+		mutex_lock(&drv_info->tx_lock);
+	}
+
+	ret = ffa_setup_and_transmit(func_id, buffer, RXTX_BUFFER_SIZE, args);
+
+	if (args->use_txbuf)
+		mutex_unlock(&drv_info->tx_lock);
+	else
+		free_pages_exact(buffer, RXTX_BUFFER_SIZE);
+
+	return ret < 0 ? ret : 0;
+}
+
+static int ffa_memory_reclaim(u64 g_handle, u32 flags)
+{
+	ffa_value_t ret;
+
+	invoke_ffa_fn((ffa_value_t){
+		      .a0 = FFA_MEM_RECLAIM,
+		      .a1 = HANDLE_LOW(g_handle), .a2 = HANDLE_HIGH(g_handle),
+		      .a3 = flags,
+		      }, &ret);
+
+	if (ret.a0 == FFA_ERROR)
+		return ffa_to_linux_errno((int)ret.a2);
+
+	return 0;
+}
+
+static u32 ffa_api_version_get(void)
+{
+	return drv_info->version;
+}
+
+static int ffa_partition_info_get(const char *uuid_str,
+				  struct ffa_partition_info *buffer)
+{
+	int count;
+	uuid_t uuid;
+	struct ffa_partition_info *pbuf;
+
+	if (uuid_parse(uuid_str, &uuid)) {
+		pr_err("invalid uuid (%s)\n", uuid_str);
+		return -ENODEV;
+	}
+
+	count = ffa_partition_probe(&uuid_null, &pbuf);
+	if (count <= 0)
+		return -ENOENT;
+
+	memcpy(buffer, pbuf, sizeof(*pbuf) * count);
+	kfree(pbuf);
+	return 0;
+}
+
+static void ffa_mode_32bit_set(struct ffa_device *dev)
+{
+	dev->mode_32bit = true;
+}
+
+static int ffa_sync_send_receive(struct ffa_device *dev,
+				 struct ffa_send_direct_data *data)
+{
+	return ffa_msg_send_direct_req(drv_info->vm_id, dev->vm_id,
+				       dev->mode_32bit, data);
+}
+
+static int
+ffa_memory_share(struct ffa_device *dev, struct ffa_mem_ops_args *args)
+{
+	if (dev->mode_32bit)
+		return ffa_memory_ops(FFA_MEM_SHARE, args);
+
+	return ffa_memory_ops(FFA_FN_NATIVE(MEM_SHARE), args);
+}
+
+static const struct ffa_dev_ops ffa_ops = {
+	.api_version_get = ffa_api_version_get,
+	.partition_info_get = ffa_partition_info_get,
+	.mode_32bit_set = ffa_mode_32bit_set,
+	.sync_send_receive = ffa_sync_send_receive,
+	.memory_reclaim = ffa_memory_reclaim,
+	.memory_share = ffa_memory_share,
+};
+
+const struct ffa_dev_ops *ffa_dev_ops_get(struct ffa_device *dev)
+{
+	if (ffa_device_is_valid(dev))
+		return &ffa_ops;
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(ffa_dev_ops_get);
+
+void ffa_device_match_uuid(struct ffa_device *ffa_dev, const uuid_t *uuid)
+{
+	int count, idx;
+	struct ffa_partition_info *pbuf, *tpbuf;
+
+	count = ffa_partition_probe(uuid, &pbuf);
+	if (count <= 0)
+		return;
+
+	for (idx = 0, tpbuf = pbuf; idx < count; idx++, tpbuf++)
+		if (tpbuf->id == ffa_dev->vm_id)
+			uuid_copy(&ffa_dev->uuid, uuid);
+	kfree(pbuf);
+}
+
+static void ffa_setup_partitions(void)
+{
+	int count, idx;
+	struct ffa_device *ffa_dev;
+	struct ffa_partition_info *pbuf, *tpbuf;
+
+	count = ffa_partition_probe(&uuid_null, &pbuf);
+	if (count <= 0) {
+		pr_info("%s: No partitions found, error %d\n", __func__, count);
+		return;
+	}
+
+	for (idx = 0, tpbuf = pbuf; idx < count; idx++, tpbuf++) {
+		/* Note that the &uuid_null parameter will require
+		 * ffa_device_match() to find the UUID of this partition id
+		 * with help of ffa_device_match_uuid(). Once the FF-A spec
+		 * is updated to provide correct UUID here for each partition
+		 * as part of the discovery API, we need to pass the
+		 * discovered UUID here instead.
+		 */
+		ffa_dev = ffa_device_register(&uuid_null, tpbuf->id);
+		if (!ffa_dev) {
+			pr_err("%s: failed to register partition ID 0x%x\n",
+			       __func__, tpbuf->id);
+			continue;
+		}
+
+		ffa_dev_set_drvdata(ffa_dev, drv_info);
+	}
+	kfree(pbuf);
+}
+
+static int __init ffa_init(void)
+{
+	int ret;
+
+	ret = ffa_transport_init(&invoke_ffa_fn);
+	if (ret)
+		return ret;
+
+	ret = arm_ffa_bus_init();
+	if (ret)
+		return ret;
+
+	drv_info = kzalloc(sizeof(*drv_info), GFP_KERNEL);
+	if (!drv_info) {
+		ret = -ENOMEM;
+		goto ffa_bus_exit;
+	}
+
+	ret = ffa_version_check(&drv_info->version);
+	if (ret)
+		goto free_drv_info;
+
+	if (ffa_id_get(&drv_info->vm_id)) {
+		pr_err("failed to obtain VM id for self\n");
+		ret = -ENODEV;
+		goto free_drv_info;
+	}
+
+	drv_info->rx_buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL);
+	if (!drv_info->rx_buffer) {
+		ret = -ENOMEM;
+		goto free_pages;
+	}
+
+	drv_info->tx_buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL);
+	if (!drv_info->tx_buffer) {
+		ret = -ENOMEM;
+		goto free_pages;
+	}
+
+	ret = ffa_rxtx_map(virt_to_phys(drv_info->tx_buffer),
+			   virt_to_phys(drv_info->rx_buffer),
+			   RXTX_BUFFER_SIZE / FFA_PAGE_SIZE);
+	if (ret) {
+		pr_err("failed to register FFA RxTx buffers\n");
+		goto free_pages;
+	}
+
+	mutex_init(&drv_info->rx_lock);
+	mutex_init(&drv_info->tx_lock);
+
+	ffa_setup_partitions();
+
+	return 0;
+free_pages:
+	if (drv_info->tx_buffer)
+		free_pages_exact(drv_info->tx_buffer, RXTX_BUFFER_SIZE);
+	free_pages_exact(drv_info->rx_buffer, RXTX_BUFFER_SIZE);
+free_drv_info:
+	kfree(drv_info);
+ffa_bus_exit:
+	arm_ffa_bus_exit();
+	return ret;
+}
+subsys_initcall(ffa_init);
+
+static void __exit ffa_exit(void)
+{
+	ffa_rxtx_unmap(drv_info->vm_id);
+	free_pages_exact(drv_info->tx_buffer, RXTX_BUFFER_SIZE);
+	free_pages_exact(drv_info->rx_buffer, RXTX_BUFFER_SIZE);
+	kfree(drv_info);
+	arm_ffa_bus_exit();
+}
+module_exit(ffa_exit);
+
+MODULE_ALIAS("arm-ffa");
+MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
+MODULE_DESCRIPTION("Arm FF-A interface driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/firmware/arm_ffa/smccc.c b/drivers/firmware/arm_ffa/smccc.c
new file mode 100644
index 000000000000..4d85bfff0a4e
--- /dev/null
+++ b/drivers/firmware/arm_ffa/smccc.c
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2021 ARM Ltd.
+ */
+
+#include <linux/printk.h>
+
+#include "common.h"
+
+static void __arm_ffa_fn_smc(ffa_value_t args, ffa_value_t *res)
+{
+	arm_smccc_1_2_smc(&args, res);
+}
+
+static void __arm_ffa_fn_hvc(ffa_value_t args, ffa_value_t *res)
+{
+	arm_smccc_1_2_hvc(&args, res);
+}
+
+int __init ffa_transport_init(ffa_fn **invoke_ffa_fn)
+{
+	enum arm_smccc_conduit conduit;
+
+	if (arm_smccc_get_version() < ARM_SMCCC_VERSION_1_2)
+		return -EOPNOTSUPP;
+
+	conduit = arm_smccc_1_1_get_conduit();
+	if (conduit == SMCCC_CONDUIT_NONE) {
+		pr_err("%s: invalid SMCCC conduit\n", __func__);
+		return -EOPNOTSUPP;
+	}
+
+	if (conduit == SMCCC_CONDUIT_SMC)
+		*invoke_ffa_fn = __arm_ffa_fn_smc;
+	else
+		*invoke_ffa_fn = __arm_ffa_fn_hvc;
+
+	return 0;
+}