[PATCH v4 0/7] firmware: Add initial support for Arm FF-A

@@ -0,0 +1,58 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/arm/arm,ffa.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Arm Firmware Framework for Arm v8-A (in-kernel users)
+
+maintainers:
+  - Sudeep Holla <sudeep.holla@arm.com>
+
+description: |
+  Firmware frameworks implementing partition according to the FF-A
+  specification defined by ARM document number ARM DEN 0077A ("Arm Firmware
+  Framework for Arm v8-A") [0], providing services to be used by other
+  partitions.
+
+  [0] https://developer.arm.com/docs/den0077/latest
+
+properties:
+  $nodename:
+    const: ffa
+
+  compatible:
+    oneOf:
+      - const: arm,ffa-1.0
+
+patternProperties:
+  "^ffa_partition[0-9]+$":
+    type: object
+    description: One or more child nodes, each describing an FFA partition.
+    properties:
+      $nodename:
+        const: ffa_partition
+
+      compatible:
+        oneOf:
+          - const: arm,ffa-1.0-partition
+
+      uuid:
+        $ref: '/schemas/types.yaml#definitions/string'
+        description: |
+          The 128-bit UUID [2] of the service implemented by this partition.
+
+          [2] https://tools.ietf.org/html/rfc4122
+
+additionalProperties: false
+
+examples:
+  - |
+    ffa {
+      compatible = "arm,ffa-1.0";
+
+      ffa_partition0 {
+        compatible = "arm,ffa-1.0-partition";
+        uuid = "12345678-9abc-def0-1234-56789abcdef0";
+      };
+    };

@@ -129,6 +129,10 @@ int main(void)
   DEFINE(ARM_SMCCC_RES_X2_OFFS,		offsetof(struct arm_smccc_res, a2));
   DEFINE(ARM_SMCCC_QUIRK_ID_OFFS,	offsetof(struct arm_smccc_quirk, id));
   DEFINE(ARM_SMCCC_QUIRK_STATE_OFFS,	offsetof(struct arm_smccc_quirk, state));
+  DEFINE(ARM_SMCCC_V1_2_RES_X0_OFFS,	offsetof(struct arm_smccc_v1_2_res, a0));
+  DEFINE(ARM_SMCCC_V1_2_RES_X2_OFFS,	offsetof(struct arm_smccc_v1_2_res, a2));
+  DEFINE(ARM_SMCCC_V1_2_RES_X4_OFFS,	offsetof(struct arm_smccc_v1_2_res, a4));
+  DEFINE(ARM_SMCCC_V1_2_RES_X6_OFFS,	offsetof(struct arm_smccc_v1_2_res, a6));
   BLANK();
   DEFINE(HIBERN_PBE_ORIG,	offsetof(struct pbe, orig_address));
   DEFINE(HIBERN_PBE_ADDR,	offsetof(struct pbe, address));

@@ -43,3 +43,25 @@ SYM_FUNC_START(__arm_smccc_hvc)
 	SMCCC	hvc
 SYM_FUNC_END(__arm_smccc_hvc)
 EXPORT_SYMBOL(__arm_smccc_hvc)
+
+	.macro SMCCC_v1_2 instr
+	.cfi_startproc
+	\instr #0
+	ldr x8, [sp]
+	stp x0, x1, [x8, #ARM_SMCCC_V1_2_RES_X0_OFFS]
+	stp x2, x3, [x8, #ARM_SMCCC_V1_2_RES_X2_OFFS]
+	stp x4, x5, [x8, #ARM_SMCCC_V1_2_RES_X4_OFFS]
+	stp x6, x7, [x8, #ARM_SMCCC_V1_2_RES_X6_OFFS]
+	ret
+	.cfi_endproc
+.endm
+
+SYM_FUNC_START(arm_smccc_v1_2_hvc)
+	SMCCC_v1_2 hvc
+SYM_FUNC_END(arm_smccc_v1_2_hvc)
+EXPORT_SYMBOL(arm_smccc_v1_2_hvc)
+
+SYM_FUNC_START(arm_smccc_v1_2_smc)
+	SMCCC_v1_2 smc
+SYM_FUNC_END(arm_smccc_v1_2_smc)
+EXPORT_SYMBOL(arm_smccc_v1_2_smc)

@@ -155,6 +155,56 @@ struct arm_smccc_res {
 	unsigned long a3;
 };
 
+#ifdef CONFIG_ARM64
+/* TODO Need to implement for ARM too */
+/**
+ * struct arm_smccc_v1_2_res - Result from SMC/HVC call
+ * @a0-a7 result values from registers 0 to 7
+ */
+struct arm_smccc_v1_2_res {
+	unsigned long a0;
+	unsigned long a1;
+	unsigned long a2;
+	unsigned long a3;
+	unsigned long a4;
+	unsigned long a5;
+	unsigned long a6;
+	unsigned long a7;
+};
+
+/**
+ * arm_smccc_v1_2_hvc() - make HVC calls
+ * @a0-a7: arguments passed in registers 0 to 7
+ * @res: result values from registers 0 to 7
+ *
+ * This function is used to make HVC calls following SMC Calling Convention
+ * v1.2 or above. The content of the supplied param are copied to registers
+ * 0 to 7 prior to the HVC instruction. The return values are updated with
+ * the content from register 0 to 7 on return from the HVC instruction.
+ */
+asmlinkage
+void arm_smccc_v1_2_hvc(unsigned long a0, unsigned long a1, unsigned long a2,
+			unsigned long a3, unsigned long a4, unsigned long a5,
+			unsigned long a6, unsigned long a7,
+			struct arm_smccc_v1_2_res  *res);
+
+/**
+ * arm_smccc_v1_2_smc() - make SMC calls
+ * @a0-a7: arguments passed in registers 0 to 7
+ * @res: result values from registers 0 to 7
+ *
+ * This function is used to make SMC calls following SMC Calling Convention
+ * v1.2 or above. The content of the supplied param are copied to registers
+ * 0 to 7 prior to the SMC instruction. The return values are updated with
+ * the content from register 0 to 7 on return from the SMC instruction.
+ */
+asmlinkage
+void arm_smccc_v1_2_smc(unsigned long a0, unsigned long a1, unsigned long a2,
+			unsigned long a3, unsigned long a4, unsigned long a5,
+			unsigned long a6, unsigned long a7,
+			struct arm_smccc_v1_2_res  *res);
+#endif
+
 /**
  * struct arm_smccc_quirk - Contains quirk information
  * @id: quirk identification

@@ -295,6 +295,7 @@ 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"

@@ -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/

@@ -0,0 +1,16 @@
+# 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.

@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
+ffa-bus-y = bus.o
+ffa-module-objs := $(ffa-bus-y)
+obj-$(CONFIG_ARM_FFA_TRANSPORT) = ffa-module.o

@@ -0,0 +1,187 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020 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>
+
+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)) {
+		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)
+{
+	uuid_t *dev_id = &to_ffa_dev(dev)->uuid;
+
+	return add_uevent_var(env, "MODALIAS=arm_ffa:%pUb", dev_id);
+}
+
+struct bus_type ffa_bus_type = {
+	.name		= "arm_ffa",
+	.match		= ffa_device_match,
+	.probe		= ffa_device_probe,
+	.uevent		= ffa_device_uevent,
+};
+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;
+	struct ffa_device *tmp_dev;
+
+	do {
+		dev = bus_find_next_device(&ffa_bus_type, NULL);
+		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 char *name, int vm_id)
+{
+	int ret;
+	struct device *dev;
+	struct ffa_device *ffa_dev;
+	uuid_t uuid = UUID_INIT(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
+
+	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, name);
+
+	ffa_dev->vm_id = vm_id;
+	if (uuid_parse(name, &uuid)) {
+		dev_err(dev, "invalid uuid (%s)\n", name);
+		kfree(ffa_dev);
+		return NULL;
+	}
+
+	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);
+
+static int __init arm_ffa_bus_init(void)
+{
+	return bus_register(&ffa_bus_type);
+}
+module_init(arm_ffa_bus_init);
+
+static void __exit arm_ffa_bus_exit(void)
+{
+	ffa_devices_unregister();
+	bus_unregister(&ffa_bus_type);
+}
+
+module_exit(arm_ffa_bus_exit);
+
+MODULE_ALIAS("arm-ffa-bus");
+MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
+MODULE_DESCRIPTION("Arm FF-A bus driver");
+MODULE_LICENSE("GPL v2");

@@ -0,0 +1,91 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2020 ARM Ltd.
+ */
+
+#ifndef _LINUX_ARM_FFA_H
+#define _LINUX_ARM_FFA_H
+
+#include <linux/cdev.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/uuid.h>
+
+/* FFA Bus/Device/Driver related */
+struct ffa_device {
+	int vm_id;
+	uuid_t uuid;
+	struct device dev;
+};
+
+#define to_ffa_dev(d) container_of(d, struct ffa_device, dev)
+
+struct ffa_device_id {
+	uuid_t uuid;
+};
+
+struct ffa_driver {
+	const char *name;
+	int (*probe)(struct ffa_device *sdev);
+	void (*remove)(struct ffa_device *sdev);
+	const struct ffa_device_id *id_table;
+
+	struct device_driver driver;
+};
+
+#define to_ffa_driver(d) container_of(d, struct ffa_driver, driver)
+
+static inline void ffa_dev_set_drvdata(struct ffa_device *fdev, void *data)
+{
+	fdev->dev.driver_data = data;
+}
+
+#if IS_REACHABLE(CONFIG_ARM_FFA_TRANSPORT)
+struct ffa_device *ffa_device_register(const char *name, int vm_id);
+void ffa_device_unregister(struct ffa_device *ffa_dev);
+int ffa_driver_register(struct ffa_driver *driver, struct module *owner,
+			const char *mod_name);
+void ffa_driver_unregister(struct ffa_driver *driver);
+bool ffa_device_is_valid(struct ffa_device *ffa_dev);
+
+#else
+static inline
+struct ffa_device *ffa_device_register(const char *name, int vm_id)
+{
+	return NULL;
+}
+
+static inline void ffa_device_unregister(struct ffa_device *dev) {}
+
+static inline int
+ffa_driver_register(struct ffa_driver *driver, struct module *owner,
+		    const char *mod_name)
+{
+	return -EINVAL;
+}
+
+static inline void ffa_driver_unregister(struct ffa_driver *driver) {}
+
+static inline
+bool ffa_device_is_valid(struct ffa_device *ffa_dev) { return false; }
+
+#endif /* CONFIG_ARM_FFA_TRANSPORT */
+
+#define ffa_register(driver) \
+	ffa_driver_register(driver, THIS_MODULE, KBUILD_MODNAME)
+#define ffa_unregister(driver) \
+	ffa_driver_unregister(driver)
+
+/**
+ * module_ffa_driver() - Helper macro for registering a psa_ffa driver
+ * @__ffa_driver: ffa_driver structure
+ *
+ * Helper macro for psa_ffa drivers to set up proper module init / exit
+ * functions.  Replaces module_init() and module_exit() and keeps people from
+ * printing pointless things to the kernel log when their driver is loaded.
+ */
+#define module_ffa_driver(__ffa_driver)	\
+	module_driver(__ffa_driver, ffa_register, ffa_unregister)
+
+#endif /* _LINUX_ARM_FFA_H */

@@ -1,4 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0-only
 ffa-bus-y = bus.o
-ffa-module-objs := $(ffa-bus-y)
+ffa-driver-y = driver.o
+ffa-module-objs := $(ffa-bus-y) $(ffa-driver-y)
 obj-$(CONFIG_ARM_FFA_TRANSPORT) = ffa-module.o

@@ -13,6 +13,8 @@
 #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;

@@ -167,21 +169,13 @@ void ffa_device_unregister(struct ffa_device *ffa_dev)
 }
 EXPORT_SYMBOL_GPL(ffa_device_unregister);
 
-static int __init arm_ffa_bus_init(void)
+int __init arm_ffa_bus_init(void)
 {
 	return bus_register(&ffa_bus_type);
 }
-module_init(arm_ffa_bus_init);
 
-static void __exit arm_ffa_bus_exit(void)
+void __exit arm_ffa_bus_exit(void)
 {
 	ffa_devices_unregister();
 	bus_unregister(&ffa_bus_type);
 }
-
-module_exit(arm_ffa_bus_exit);
-
-MODULE_ALIAS("arm-ffa-bus");
-MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
-MODULE_DESCRIPTION("Arm FF-A bus driver");
-MODULE_LICENSE("GPL v2");

@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020 ARM Ltd.
+ */
+
+#ifndef _FFA_COMMON_H
+#define _FFA_COMMON_H
+
+#include <linux/arm-smccc.h>
+#include <linux/err.h>
+
+typedef struct arm_smccc_v1_2_res ffa_res_t;
+
+typedef ffa_res_t
+(ffa_fn)(unsigned long, unsigned long, unsigned long, unsigned long,
+	 unsigned long, unsigned long, unsigned long, unsigned long);
+
+int __init arm_ffa_bus_init(void);
+void __exit arm_ffa_bus_exit(void);
+
+static inline int __init ffa_transport_init(ffa_fn **invoke_ffa_fn)
+{
+	return -EOPNOTSUPP;
+}
+
+#endif /* _FFA_COMMON_H */

@@ -0,0 +1,297 @@
+// 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) 2020 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/io.h>
+#include <linux/module.h>
+#include <linux/slab.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_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_res_t ver;
+
+	ver = invoke_ffa_fn(FFA_VERSION, FFA_DRIVER_VERSION, 0, 0, 0, 0, 0, 0);
+
+	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_rxtx_map(phys_addr_t tx_buf, phys_addr_t rx_buf, u32 pg_cnt)
+{
+	ffa_res_t ret;
+
+	ret = invoke_ffa_fn(FFA_RXTX_MAP, tx_buf, rx_buf, pg_cnt, 0, 0, 0, 0);
+
+	if (ret.a0 == FFA_ERROR)
+		return ffa_to_linux_errno((int)ret.a2);
+
+	return 0;
+}
+
+static int ffa_rxtx_unmap(u16 vm_id)
+{
+	ffa_res_t ret;
+
+	ret = invoke_ffa_fn(FFA_RXTX_UNMAP, vm_id, 0, 0, 0, 0, 0, 0);
+
+	if (ret.a0 == FFA_ERROR)
+		return ffa_to_linux_errno((int)ret.a2);
+
+	return 0;
+}
+
+#define VM_ID_MASK	GENMASK(15, 0)
+static int ffa_id_get(u16 *vm_id)
+{
+	ffa_res_t id;
+
+	id = invoke_ffa_fn(FFA_ID_GET, 0, 0, 0, 0, 0, 0, 0);
+
+	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 __init ffa_init(void)
+{
+	int ret;
+
+	ret = arm_ffa_bus_init();
+	if (ret)
+		return ret;
+
+	ret = ffa_transport_init(&invoke_ffa_fn);
+	if (ret)
+		return ret;
+
+	drv_info = kzalloc(sizeof(*drv_info), GFP_KERNEL);
+	if (!drv_info)
+		return -ENOMEM;
+
+	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);
+
+	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);
+	return ret;
+}
+module_init(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");

@@ -14,3 +14,8 @@ config ARM_FFA_TRANSPORT
 
 	  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

@@ -1,5 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0-only
 ffa-bus-y = bus.o
 ffa-driver-y = driver.o
-ffa-module-objs := $(ffa-bus-y) $(ffa-driver-y)
+ffa-transport-$(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

@@ -18,9 +18,13 @@ typedef ffa_res_t
 int __init arm_ffa_bus_init(void);
 void __exit arm_ffa_bus_exit(void);
 
+#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 */

@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020 ARM Ltd.
+ */
+
+#include <linux/printk.h>
+
+#include "common.h"
+
+static struct arm_smccc_v1_2_res
+__arm_ffa_fn_smc(unsigned long function_id, unsigned long arg0,
+		 unsigned long arg1, unsigned long arg2, unsigned long arg3,
+		 unsigned long arg4, unsigned long arg5, unsigned long arg6)
+{
+	struct arm_smccc_v1_2_res res;
+
+	arm_smccc_v1_2_smc(function_id, arg0, arg1, arg2, arg3, arg4, arg5,
+			   arg6, &res);
+
+	return res;
+}
+
+static struct arm_smccc_v1_2_res
+__arm_ffa_fn_hvc(unsigned long function_id, unsigned long arg0,
+		 unsigned long arg1, unsigned long arg2, unsigned long arg3,
+		 unsigned long arg4, unsigned long arg5, unsigned long arg6)
+{
+	struct arm_smccc_v1_2_res res;
+
+	arm_smccc_v1_2_hvc(function_id, arg0, arg1, arg2, arg3, arg4, arg5,
+			   arg6, &res);
+	return 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;
+}

@@ -6,6 +6,7 @@
 #ifndef _FFA_COMMON_H
 #define _FFA_COMMON_H
 
+#include <linux/arm_ffa.h>
 #include <linux/arm-smccc.h>
 #include <linux/err.h>
 

@@ -17,6 +18,7 @@ typedef ffa_res_t
 
 int __init arm_ffa_bus_init(void);
 void __exit arm_ffa_bus_exit(void);
+bool ffa_device_is_valid(struct ffa_device *ffa_dev);
 
 #ifdef CONFIG_ARM_FFA_SMCCC
 int __init ffa_transport_init(ffa_fn **invoke_ffa_fn);

@@ -24,9 +24,13 @@
 
 #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/of.h>
 #include <linux/slab.h>
+#include <linux/uuid.h>
 
 #include "common.h"
 

@@ -182,6 +186,20 @@ static int ffa_version_check(u32 *version)
 	return 0;
 }
 
+static int ffa_rx_release(void)
+{
+	ffa_res_t ret;
+
+	ret = invoke_ffa_fn(FFA_RX_RELEASE, 0, 0, 0, 0, 0, 0, 0);
+
+	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_res_t ret;

@@ -206,6 +224,52 @@ static int ffa_rxtx_unmap(u16 vm_id)
 	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_res_t partition_info;
+
+	mutex_lock(&drv_info->rx_lock);
+	partition_info = invoke_ffa_fn(FFA_PARTITION_INFO_GET, uuid0, uuid1,
+				       uuid2, uuid3, 0, 0, 0);
+
+	if (partition_info.a0 == FFA_ERROR)
+		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;
+}
+
+static int ffa_partition_probe(const char *uuid_str,
+			       struct ffa_partition_info *buffer)
+{
+	int count;
+	uuid_t uuid;
+	u32 uuid0_4[4] = { 0 };
+
+	if (uuid_parse(uuid_str, &uuid)) {
+		pr_err("invalid uuid (%s)\n", uuid_str);
+		return -ENODEV;
+	}
+
+	export_uuid((u8 *)uuid0_4, &uuid);
+	count = __ffa_partition_info_get(uuid0_4[0], uuid0_4[1], uuid0_4[2],
+					 uuid0_4[3], &buffer, 1);
+
+	return count != 1;
+}
+
 #define VM_ID_MASK	GENMASK(15, 0)
 static int ffa_id_get(u16 *vm_id)
 {

@@ -221,9 +285,125 @@ static int ffa_id_get(u16 *vm_id)
 	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_res_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);
+	}
+
+	ret = invoke_ffa_fn(req_id, src_dst_ids, 0, data->data0, data->data1,
+			    data->data2, data->data3, data->data4);
+
+	while (ret.a0 == FFA_INTERRUPT)
+		ret = invoke_ffa_fn(FFA_RUN, ret.a1, 0, 0, 0, 0, 0, 0);
+	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;
+}
+
+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)
+{
+	if (ffa_partition_probe(uuid_str, buffer))
+		return -ENOENT;
+	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 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,
+};
+
+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);
+
+static void ffa_setup_partitions(struct device_node *np)
+{
+	int ret;
+	struct device_node *child;
+	struct ffa_device *ffa_dev;
+	struct ffa_partition_info pbuf;
+	const char *p_uuid, *pfx = "Ignoring FFA partition";
+	uuid_t uuid = UUID_INIT(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
+
+	for_each_child_of_node(np, child) {
+		if (!of_device_is_compatible(child, "arm,ffa-1.0-partition"))
+			continue;
+
+		if (of_property_read_string(child, "uuid", &p_uuid)) {
+			pr_err("%s: failed to parse \"uuid\" property\n", pfx);
+			continue;
+		}
+
+		if (uuid_parse(p_uuid, &uuid)) {
+			pr_err("%s: invalid \"uuid\" property (%s)\n",
+			       pfx, p_uuid);
+			continue;
+		}
+
+		ret = ffa_partition_probe(p_uuid, &pbuf);
+		if (ret) {
+			pr_err("%s: %s partition info probe failed\n",
+			       pfx, p_uuid);
+			continue;
+		}
+
+		ffa_dev = ffa_device_register(p_uuid, pbuf.id);
+		if (!ffa_dev) {
+			pr_err("%s: failed to register %s\n", pfx, p_uuid);
+			continue;
+		}
+
+		ffa_dev_set_drvdata(ffa_dev, drv_info);
+	}
+}
+
 static int __init ffa_init(void)
 {
 	int ret;
+	struct device_node *np;
 
 	ret = arm_ffa_bus_init();
 	if (ret)