tee: add AMD-TEE driver

Adds AMD-TEE driver.
* targets AMD APUs which has AMD Secure Processor with software-based
  Trusted Execution Environment (TEE) support
* registers with TEE subsystem
* defines tee_driver_ops function callbacks
* kernel allocated memory is used as shared memory between normal
  world and secure world.
* acts as REE (Rich Execution Environment) communication agent, which
  uses the services of AMD Secure Processor driver to submit commands
  for processing in TEE environment

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Acked-by: NJens Wiklander <jens.wiklander@linaro.org>
Co-developed-by: NDevaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: NDevaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: NRijo Thomas <Rijo-john.Thomas@amd.com>
Reviewed-by: NGary R Hook <gary.hook@amd.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

drivers/tee/Kconfig

@@ -14,7 +14,7 @@ if TEE
 menu "TEE drivers"
 
 source "drivers/tee/optee/Kconfig"
-
+source "drivers/tee/amdtee/Kconfig"
 endmenu
 
 endif

drivers/tee/Makefile

@@ -4,3 +4,4 @@ tee-objs += tee_core.o
 tee-objs += tee_shm.o
 tee-objs += tee_shm_pool.o
 obj-$(CONFIG_OPTEE) += optee/
+obj-$(CONFIG_AMDTEE) += amdtee/

drivers/tee/amdtee/Kconfig

+# SPDX-License-Identifier: MIT
+# AMD-TEE Trusted Execution Environment Configuration
+config AMDTEE
+	tristate "AMD-TEE"
+	default m
+	depends on CRYPTO_DEV_SP_PSP
+	help
+	  This implements AMD's Trusted Execution Environment (TEE) driver.

drivers/tee/amdtee/Makefile

+# SPDX-License-Identifier: MIT
+obj-$(CONFIG_AMDTEE) += amdtee.o
+amdtee-objs += core.o
+amdtee-objs += call.o
+amdtee-objs += shm_pool.o

drivers/tee/amdtee/amdtee_if.h

+/* SPDX-License-Identifier: MIT */
+
+/*
+ * Copyright 2019 Advanced Micro Devices, Inc.
+ */
+
+/*
+ * This file has definitions related to Host and AMD-TEE Trusted OS interface.
+ * These definitions must match the definitions on the TEE side.
+ */
+
+#ifndef AMDTEE_IF_H
+#define AMDTEE_IF_H
+
+#include <linux/types.h>
+
+/*****************************************************************************
+ ** TEE Param
+ ******************************************************************************/
+#define TEE_MAX_PARAMS		4
+
+/**
+ * struct memref - memory reference structure
+ * @buf_id:    buffer ID of the buffer mapped by TEE_CMD_ID_MAP_SHARED_MEM
+ * @offset:    offset in bytes from beginning of the buffer
+ * @size:      data size in bytes
+ */
+struct memref {
+	u32 buf_id;
+	u32 offset;
+	u32 size;
+};
+
+struct value {
+	u32 a;
+	u32 b;
+};
+
+/*
+ * Parameters passed to open_session or invoke_command
+ */
+union tee_op_param {
+	struct memref mref;
+	struct value val;
+};
+
+struct tee_operation {
+	u32 param_types;
+	union tee_op_param params[TEE_MAX_PARAMS];
+};
+
+/* Must be same as in GP TEE specification */
+#define TEE_OP_PARAM_TYPE_NONE                  0
+#define TEE_OP_PARAM_TYPE_VALUE_INPUT           1
+#define TEE_OP_PARAM_TYPE_VALUE_OUTPUT          2
+#define TEE_OP_PARAM_TYPE_VALUE_INOUT           3
+#define TEE_OP_PARAM_TYPE_INVALID               4
+#define TEE_OP_PARAM_TYPE_MEMREF_INPUT          5
+#define TEE_OP_PARAM_TYPE_MEMREF_OUTPUT         6
+#define TEE_OP_PARAM_TYPE_MEMREF_INOUT          7
+
+#define TEE_PARAM_TYPE_GET(t, i)        (((t) >> ((i) * 4)) & 0xF)
+#define TEE_PARAM_TYPES(t0, t1, t2, t3) \
+	((t0) | ((t1) << 4) | ((t2) << 8) | ((t3) << 12))
+
+/*****************************************************************************
+ ** TEE Commands
+ *****************************************************************************/
+
+/*
+ * The shared memory between rich world and secure world may be physically
+ * non-contiguous. Below structures are meant to describe a shared memory region
+ * via scatter/gather (sg) list
+ */
+
+/**
+ * struct tee_sg_desc - sg descriptor for a physically contiguous buffer
+ * @low_addr: [in] bits[31:0] of buffer's physical address. Must be 4KB aligned
+ * @hi_addr:  [in] bits[63:32] of the buffer's physical address
+ * @size:     [in] size in bytes (must be multiple of 4KB)
+ */
+struct tee_sg_desc {
+	u32 low_addr;
+	u32 hi_addr;
+	u32 size;
+};
+
+/**
+ * struct tee_sg_list - structure describing a scatter/gather list
+ * @count:   [in] number of sg descriptors
+ * @size:    [in] total size of all buffers in the list. Must be multiple of 4KB
+ * @buf:     [in] list of sg buffer descriptors
+ */
+#define TEE_MAX_SG_DESC 64
+struct tee_sg_list {
+	u32 count;
+	u32 size;
+	struct tee_sg_desc buf[TEE_MAX_SG_DESC];
+};
+
+/**
+ * struct tee_cmd_map_shared_mem - command to map shared memory
+ * @buf_id:    [out] return buffer ID value
+ * @sg_list:   [in] list describing memory to be mapped
+ */
+struct tee_cmd_map_shared_mem {
+	u32 buf_id;
+	struct tee_sg_list sg_list;
+};
+
+/**
+ * struct tee_cmd_unmap_shared_mem - command to unmap shared memory
+ * @buf_id:    [in] buffer ID of memory to be unmapped
+ */
+struct tee_cmd_unmap_shared_mem {
+	u32 buf_id;
+};
+
+/**
+ * struct tee_cmd_load_ta - load Trusted Application (TA) binary into TEE
+ * @low_addr:    [in] bits [31:0] of the physical address of the TA binary
+ * @hi_addr:     [in] bits [63:32] of the physical address of the TA binary
+ * @size:        [in] size of TA binary in bytes
+ * @ta_handle:   [out] return handle of the loaded TA
+ */
+struct tee_cmd_load_ta {
+	u32 low_addr;
+	u32 hi_addr;
+	u32 size;
+	u32 ta_handle;
+};
+
+/**
+ * struct tee_cmd_unload_ta - command to unload TA binary from TEE environment
+ * @ta_handle:    [in] handle of the loaded TA to be unloaded
+ */
+struct tee_cmd_unload_ta {
+	u32 ta_handle;
+};
+
+/**
+ * struct tee_cmd_open_session - command to call TA_OpenSessionEntryPoint in TA
+ * @ta_handle:      [in] handle of the loaded TA
+ * @session_info:   [out] pointer to TA allocated session data
+ * @op:             [in/out] operation parameters
+ * @return_origin:  [out] origin of return code after TEE processing
+ */
+struct tee_cmd_open_session {
+	u32 ta_handle;
+	u32 session_info;
+	struct tee_operation op;
+	u32 return_origin;
+};
+
+/**
+ * struct tee_cmd_close_session - command to call TA_CloseSessionEntryPoint()
+ *                                in TA
+ * @ta_handle:      [in] handle of the loaded TA
+ * @session_info:   [in] pointer to TA allocated session data
+ */
+struct tee_cmd_close_session {
+	u32 ta_handle;
+	u32 session_info;
+};
+
+/**
+ * struct tee_cmd_invoke_cmd - command to call TA_InvokeCommandEntryPoint() in
+ *                             TA
+ * @ta_handle:     [in] handle of the loaded TA
+ * @cmd_id:        [in] TA command ID
+ * @session_info:  [in] pointer to TA allocated session data
+ * @op:            [in/out] operation parameters
+ * @return_origin: [out] origin of return code after TEE processing
+ */
+struct tee_cmd_invoke_cmd {
+	u32 ta_handle;
+	u32 cmd_id;
+	u32 session_info;
+	struct tee_operation op;
+	u32 return_origin;
+};
+
+#endif /*AMDTEE_IF_H*/

drivers/tee/amdtee/amdtee_private.h

+/* SPDX-License-Identifier: MIT */
+
+/*
+ * Copyright 2019 Advanced Micro Devices, Inc.
+ */
+
+#ifndef AMDTEE_PRIVATE_H
+#define AMDTEE_PRIVATE_H
+
+#include <linux/mutex.h>
+#include <linux/spinlock.h>
+#include <linux/tee_drv.h>
+#include <linux/kref.h>
+#include <linux/types.h>
+#include "amdtee_if.h"
+
+#define DRIVER_NAME	"amdtee"
+#define DRIVER_AUTHOR   "AMD-TEE Linux driver team"
+
+/* Some GlobalPlatform error codes used in this driver */
+#define TEEC_SUCCESS			0x00000000
+#define TEEC_ERROR_GENERIC		0xFFFF0000
+#define TEEC_ERROR_BAD_PARAMETERS	0xFFFF0006
+#define TEEC_ERROR_COMMUNICATION	0xFFFF000E
+
+#define TEEC_ORIGIN_COMMS		0x00000002
+
+/* Maximum number of sessions which can be opened with a Trusted Application */
+#define TEE_NUM_SESSIONS			32
+
+#define TA_LOAD_PATH				"/amdtee"
+#define TA_PATH_MAX				60
+
+/**
+ * struct amdtee - main service struct
+ * @teedev:		client device
+ * @pool:		shared memory pool
+ */
+struct amdtee {
+	struct tee_device *teedev;
+	struct tee_shm_pool *pool;
+};
+
+/**
+ * struct amdtee_session - Trusted Application (TA) session related information.
+ * @ta_handle:     handle to Trusted Application (TA) loaded in TEE environment
+ * @refcount:      counter to keep track of sessions opened for the TA instance
+ * @session_info:  an array pointing to TA allocated session data.
+ * @sess_mask:     session usage bit-mask. If a particular bit is set, then the
+ *                 corresponding @session_info entry is in use or valid.
+ *
+ * Session structure is updated on open_session and this information is used for
+ * subsequent operations with the Trusted Application.
+ */
+struct amdtee_session {
+	struct list_head list_node;
+	u32 ta_handle;
+	struct kref refcount;
+	u32 session_info[TEE_NUM_SESSIONS];
+	DECLARE_BITMAP(sess_mask, TEE_NUM_SESSIONS);
+	spinlock_t lock;	/* synchronizes access to @sess_mask */
+};
+
+/**
+ * struct amdtee_context_data - AMD-TEE driver context data
+ * @sess_list:    Keeps track of sessions opened in current TEE context
+ */
+struct amdtee_context_data {
+	struct list_head sess_list;
+};
+
+struct amdtee_driver_data {
+	struct amdtee *amdtee;
+};
+
+struct shmem_desc {
+	void *kaddr;
+	u64 size;
+};
+
+/**
+ * struct amdtee_shm_data - Shared memory data
+ * @kaddr:	Kernel virtual address of shared memory
+ * @buf_id:	Buffer id of memory mapped by TEE_CMD_ID_MAP_SHARED_MEM
+ */
+struct amdtee_shm_data {
+	struct  list_head shm_node;
+	void    *kaddr;
+	u32     buf_id;
+};
+
+struct amdtee_shm_context {
+	struct list_head shmdata_list;
+};
+
+#define LOWER_TWO_BYTE_MASK	0x0000FFFF
+
+/**
+ * set_session_id() - Sets the session identifier.
+ * @ta_handle:      [in] handle of the loaded Trusted Application (TA)
+ * @session_index:  [in] Session index. Range: 0 to (TEE_NUM_SESSIONS - 1).
+ * @session:        [out] Pointer to session id
+ *
+ * Lower two bytes of the session identifier represents the TA handle and the
+ * upper two bytes is session index.
+ */
+static inline void set_session_id(u32 ta_handle, u32 session_index,
+				  u32 *session)
+{
+	*session = (session_index << 16) | (LOWER_TWO_BYTE_MASK & ta_handle);
+}
+
+static inline u32 get_ta_handle(u32 session)
+{
+	return session & LOWER_TWO_BYTE_MASK;
+}
+
+static inline u32 get_session_index(u32 session)
+{
+	return (session >> 16) & LOWER_TWO_BYTE_MASK;
+}
+
+int amdtee_open_session(struct tee_context *ctx,
+			struct tee_ioctl_open_session_arg *arg,
+			struct tee_param *param);
+
+int amdtee_close_session(struct tee_context *ctx, u32 session);
+
+int amdtee_invoke_func(struct tee_context *ctx,
+		       struct tee_ioctl_invoke_arg *arg,
+		       struct tee_param *param);
+
+int amdtee_cancel_req(struct tee_context *ctx, u32 cancel_id, u32 session);
+
+int amdtee_map_shmem(struct tee_shm *shm);
+
+void amdtee_unmap_shmem(struct tee_shm *shm);
+
+int handle_load_ta(void *data, u32 size,
+		   struct tee_ioctl_open_session_arg *arg);
+
+int handle_unload_ta(u32 ta_handle);
+
+int handle_open_session(struct tee_ioctl_open_session_arg *arg, u32 *info,
+			struct tee_param *p);
+
+int handle_close_session(u32 ta_handle, u32 info);
+
+int handle_map_shmem(u32 count, struct shmem_desc *start, u32 *buf_id);
+
+void handle_unmap_shmem(u32 buf_id);
+
+int handle_invoke_cmd(struct tee_ioctl_invoke_arg *arg, u32 sinfo,
+		      struct tee_param *p);
+
+struct tee_shm_pool *amdtee_config_shm(void);
+
+u32 get_buffer_id(struct tee_shm *shm);
+#endif /*AMDTEE_PRIVATE_H*/

drivers/tee/amdtee/call.c

+// SPDX-License-Identifier: MIT
+/*
+ * Copyright 2019 Advanced Micro Devices, Inc.
+ */
+
+#include <linux/device.h>
+#include <linux/tee.h>
+#include <linux/tee_drv.h>
+#include <linux/psp-tee.h>
+#include <linux/slab.h>
+#include <linux/psp-sev.h>
+#include "amdtee_if.h"
+#include "amdtee_private.h"
+
+static int tee_params_to_amd_params(struct tee_param *tee, u32 count,
+				    struct tee_operation *amd)
+{
+	int i, ret = 0;
+	u32 type;
+
+	if (!count)
+		return 0;
+
+	if (!tee || !amd || count > TEE_MAX_PARAMS)
+		return -EINVAL;
+
+	amd->param_types = 0;
+	for (i = 0; i < count; i++) {
+		/* AMD TEE does not support meta parameter */
+		if (tee[i].attr > TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT)
+			return -EINVAL;
+
+		amd->param_types |= ((tee[i].attr & 0xF) << i * 4);
+	}
+
+	for (i = 0; i < count; i++) {
+		type = TEE_PARAM_TYPE_GET(amd->param_types, i);
+		pr_debug("%s: type[%d] = 0x%x\n", __func__, i, type);
+
+		if (type == TEE_OP_PARAM_TYPE_INVALID)
+			return -EINVAL;
+
+		if (type == TEE_OP_PARAM_TYPE_NONE)
+			continue;
+
+		/* It is assumed that all values are within 2^32-1 */
+		if (type > TEE_OP_PARAM_TYPE_VALUE_INOUT) {
+			u32 buf_id = get_buffer_id(tee[i].u.memref.shm);
+
+			amd->params[i].mref.buf_id = buf_id;
+			amd->params[i].mref.offset = tee[i].u.memref.shm_offs;
+			amd->params[i].mref.size = tee[i].u.memref.size;
+			pr_debug("%s: bufid[%d] = 0x%x, offset[%d] = 0x%x, size[%d] = 0x%x\n",
+				 __func__,
+				 i, amd->params[i].mref.buf_id,
+				 i, amd->params[i].mref.offset,
+				 i, amd->params[i].mref.size);
+		} else {
+			if (tee[i].u.value.c)
+				pr_warn("%s: Discarding value c", __func__);
+
+			amd->params[i].val.a = tee[i].u.value.a;
+			amd->params[i].val.b = tee[i].u.value.b;
+			pr_debug("%s: a[%d] = 0x%x, b[%d] = 0x%x\n", __func__,
+				 i, amd->params[i].val.a,
+				 i, amd->params[i].val.b);
+		}
+	}
+	return ret;
+}
+
+static int amd_params_to_tee_params(struct tee_param *tee, u32 count,
+				    struct tee_operation *amd)
+{
+	int i, ret = 0;
+	u32 type;
+
+	if (!count)
+		return 0;
+
+	if (!tee || !amd || count > TEE_MAX_PARAMS)
+		return -EINVAL;
+
+	/* Assumes amd->param_types is valid */
+	for (i = 0; i < count; i++) {
+		type = TEE_PARAM_TYPE_GET(amd->param_types, i);
+		pr_debug("%s: type[%d] = 0x%x\n", __func__, i, type);
+
+		if (type == TEE_OP_PARAM_TYPE_INVALID ||
+		    type > TEE_OP_PARAM_TYPE_MEMREF_INOUT)
+			return -EINVAL;
+
+		if (type == TEE_OP_PARAM_TYPE_NONE ||
+		    type == TEE_OP_PARAM_TYPE_VALUE_INPUT ||
+		    type == TEE_OP_PARAM_TYPE_MEMREF_INPUT)
+			continue;
+
+		/*
+		 * It is assumed that buf_id remains unchanged for
+		 * both open_session and invoke_cmd call
+		 */
+		if (type > TEE_OP_PARAM_TYPE_MEMREF_INPUT) {
+			tee[i].u.memref.shm_offs = amd->params[i].mref.offset;
+			tee[i].u.memref.size = amd->params[i].mref.size;
+			pr_debug("%s: bufid[%d] = 0x%x, offset[%d] = 0x%x, size[%d] = 0x%x\n",
+				 __func__,
+				 i, amd->params[i].mref.buf_id,
+				 i, amd->params[i].mref.offset,
+				 i, amd->params[i].mref.size);
+		} else {
+			/* field 'c' not supported by AMD TEE */
+			tee[i].u.value.a = amd->params[i].val.a;
+			tee[i].u.value.b = amd->params[i].val.b;
+			tee[i].u.value.c = 0;
+			pr_debug("%s: a[%d] = 0x%x, b[%d] = 0x%x\n",
+				 __func__,
+				 i, amd->params[i].val.a,
+				 i, amd->params[i].val.b);
+		}
+	}
+	return ret;
+}
+
+int handle_unload_ta(u32 ta_handle)
+{
+	struct tee_cmd_unload_ta cmd = {0};
+	int ret = 0;
+	u32 status;
+
+	if (!ta_handle)
+		return -EINVAL;
+
+	cmd.ta_handle = ta_handle;
+
+	ret = psp_tee_process_cmd(TEE_CMD_ID_UNLOAD_TA, (void *)&cmd,
+				  sizeof(cmd), &status);
+	if (!ret && status != 0) {
+		pr_err("unload ta: status = 0x%x\n", status);
+		ret = -EBUSY;
+	}
+
+	return ret;
+}
+
+int handle_close_session(u32 ta_handle, u32 info)
+{
+	struct tee_cmd_close_session cmd = {0};
+	int ret = 0;
+	u32 status;
+
+	if (ta_handle == 0)
+		return -EINVAL;
+
+	cmd.ta_handle = ta_handle;
+	cmd.session_info = info;
+
+	ret = psp_tee_process_cmd(TEE_CMD_ID_CLOSE_SESSION, (void *)&cmd,
+				  sizeof(cmd), &status);
+	if (!ret && status != 0) {
+		pr_err("close session: status = 0x%x\n", status);
+		ret = -EBUSY;
+	}
+
+	return ret;
+}
+
+void handle_unmap_shmem(u32 buf_id)
+{
+	struct tee_cmd_unmap_shared_mem cmd = {0};
+	int ret = 0;
+	u32 status;
+
+	cmd.buf_id = buf_id;
+
+	ret = psp_tee_process_cmd(TEE_CMD_ID_UNMAP_SHARED_MEM, (void *)&cmd,
+				  sizeof(cmd), &status);
+	if (!ret)
+		pr_debug("unmap shared memory: buf_id %u status = 0x%x\n",
+			 buf_id, status);
+}
+
+int handle_invoke_cmd(struct tee_ioctl_invoke_arg *arg, u32 sinfo,
+		      struct tee_param *p)
+{
+	struct tee_cmd_invoke_cmd cmd = {0};
+	int ret = 0;
+
+	if (!arg || (!p && arg->num_params))
+		return -EINVAL;
+
+	arg->ret_origin = TEEC_ORIGIN_COMMS;
+
+	if (arg->session == 0) {
+		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
+		return -EINVAL;
+	}
+
+	ret = tee_params_to_amd_params(p, arg->num_params, &cmd.op);
+	if (ret) {
+		pr_err("invalid Params. Abort invoke command\n");
+		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
+		return ret;
+	}
+
+	cmd.ta_handle = get_ta_handle(arg->session);
+	cmd.cmd_id = arg->func;
+	cmd.session_info = sinfo;
+
+	ret = psp_tee_process_cmd(TEE_CMD_ID_INVOKE_CMD, (void *)&cmd,
+				  sizeof(cmd), &arg->ret);
+	if (ret) {
+		arg->ret = TEEC_ERROR_COMMUNICATION;
+	} else {
+		ret = amd_params_to_tee_params(p, arg->num_params, &cmd.op);
+		if (unlikely(ret)) {
+			pr_err("invoke command: failed to copy output\n");
+			arg->ret = TEEC_ERROR_GENERIC;
+			return ret;
+		}
+		arg->ret_origin = cmd.return_origin;
+		pr_debug("invoke command: RO = 0x%x ret = 0x%x\n",
+			 arg->ret_origin, arg->ret);
+	}
+
+	return ret;
+}
+
+int handle_map_shmem(u32 count, struct shmem_desc *start, u32 *buf_id)
+{
+	struct tee_cmd_map_shared_mem *cmd;
+	phys_addr_t paddr;
+	int ret = 0, i;
+	u32 status;
+
+	if (!count || !start || !buf_id)
+		return -EINVAL;
+
+	cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
+	if (!cmd)
+		return -ENOMEM;
+
+	/* Size must be page aligned */
+	for (i = 0; i < count ; i++) {
+		if (!start[i].kaddr || (start[i].size & (PAGE_SIZE - 1))) {
+			ret = -EINVAL;
+			goto free_cmd;
+		}
+
+		if ((u64)start[i].kaddr & (PAGE_SIZE - 1)) {
+			pr_err("map shared memory: page unaligned. addr 0x%llx",
+			       (u64)start[i].kaddr);
+			ret = -EINVAL;
+			goto free_cmd;
+		}
+	}
+
+	cmd->sg_list.count = count;
+
+	/* Create buffer list */
+	for (i = 0; i < count ; i++) {
+		paddr = __psp_pa(start[i].kaddr);
+		cmd->sg_list.buf[i].hi_addr = upper_32_bits(paddr);
+		cmd->sg_list.buf[i].low_addr = lower_32_bits(paddr);
+		cmd->sg_list.buf[i].size = start[i].size;
+		cmd->sg_list.size += cmd->sg_list.buf[i].size;
+
+		pr_debug("buf[%d]:hi addr = 0x%x\n", i,
+			 cmd->sg_list.buf[i].hi_addr);
+		pr_debug("buf[%d]:low addr = 0x%x\n", i,
+			 cmd->sg_list.buf[i].low_addr);
+		pr_debug("buf[%d]:size = 0x%x\n", i, cmd->sg_list.buf[i].size);
+		pr_debug("list size = 0x%x\n", cmd->sg_list.size);
+	}
+
+	*buf_id = 0;
+
+	ret = psp_tee_process_cmd(TEE_CMD_ID_MAP_SHARED_MEM, (void *)cmd,
+				  sizeof(*cmd), &status);
+	if (!ret && !status) {
+		*buf_id = cmd->buf_id;
+		pr_debug("mapped buffer ID = 0x%x\n", *buf_id);
+	} else {
+		pr_err("map shared memory: status = 0x%x\n", status);
+		ret = -ENOMEM;
+	}
+
+free_cmd:
+	kfree(cmd);
+
+	return ret;
+}
+
+int handle_open_session(struct tee_ioctl_open_session_arg *arg, u32 *info,
+			struct tee_param *p)
+{
+	struct tee_cmd_open_session cmd = {0};
+	int ret = 0;
+
+	if (!arg || !info || (!p && arg->num_params))
+		return -EINVAL;
+
+	arg->ret_origin = TEEC_ORIGIN_COMMS;
+
+	if (arg->session == 0) {
+		arg->ret = TEEC_ERROR_GENERIC;
+		return -EINVAL;
+	}
+
+	ret = tee_params_to_amd_params(p, arg->num_params, &cmd.op);
+	if (ret) {
+		pr_err("invalid Params. Abort open session\n");
+		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
+		return ret;
+	}
+
+	cmd.ta_handle = get_ta_handle(arg->session);
+	*info = 0;
+
+	ret = psp_tee_process_cmd(TEE_CMD_ID_OPEN_SESSION, (void *)&cmd,
+				  sizeof(cmd), &arg->ret);
+	if (ret) {
+		arg->ret = TEEC_ERROR_COMMUNICATION;
+	} else {
+		ret = amd_params_to_tee_params(p, arg->num_params, &cmd.op);
+		if (unlikely(ret)) {
+			pr_err("open session: failed to copy output\n");
+			arg->ret = TEEC_ERROR_GENERIC;
+			return ret;
+		}
+		arg->ret_origin = cmd.return_origin;
+		*info = cmd.session_info;
+		pr_debug("open session: session info = 0x%x\n", *info);
+	}
+
+	pr_debug("open session: ret = 0x%x RO = 0x%x\n", arg->ret,
+		 arg->ret_origin);
+
+	return ret;
+}
+
+int handle_load_ta(void *data, u32 size, struct tee_ioctl_open_session_arg *arg)
+{
+	struct tee_cmd_load_ta cmd = {0};
+	phys_addr_t blob;
+	int ret = 0;
+
+	if (size == 0 || !data || !arg)
+		return -EINVAL;
+
+	blob = __psp_pa(data);
+	if (blob & (PAGE_SIZE - 1)) {
+		pr_err("load TA: page unaligned. blob 0x%llx", blob);
+		return -EINVAL;
+	}
+
+	cmd.hi_addr = upper_32_bits(blob);
+	cmd.low_addr = lower_32_bits(blob);
+	cmd.size = size;
+
+	ret = psp_tee_process_cmd(TEE_CMD_ID_LOAD_TA, (void *)&cmd,
+				  sizeof(cmd), &arg->ret);
+	if (ret) {
+		arg->ret_origin = TEEC_ORIGIN_COMMS;
+		arg->ret = TEEC_ERROR_COMMUNICATION;
+	} else {
+		set_session_id(cmd.ta_handle, 0, &arg->session);
+	}
+
+	pr_debug("load TA: TA handle = 0x%x, RO = 0x%x, ret = 0x%x\n",
+		 cmd.ta_handle, arg->ret_origin, arg->ret);
+
+	return 0;
+}

drivers/tee/amdtee/core.c

+// SPDX-License-Identifier: MIT
+/*
+ * Copyright 2019 Advanced Micro Devices, Inc.
+ */
+
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/device.h>
+#include <linux/tee_drv.h>
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/uaccess.h>
+#include <linux/firmware.h>
+#include "amdtee_private.h"
+#include "../tee_private.h"
+
+static struct amdtee_driver_data *drv_data;
+static DEFINE_MUTEX(session_list_mutex);
+static struct amdtee_shm_context shmctx;
+
+static void amdtee_get_version(struct tee_device *teedev,
+			       struct tee_ioctl_version_data *vers)
+{
+	struct tee_ioctl_version_data v = {
+		.impl_id = TEE_IMPL_ID_AMDTEE,
+		.impl_caps = 0,
+		.gen_caps = TEE_GEN_CAP_GP,
+	};
+	*vers = v;
+}
+
+static int amdtee_open(struct tee_context *ctx)
+{
+	struct amdtee_context_data *ctxdata;
+
+	ctxdata = kzalloc(sizeof(*ctxdata), GFP_KERNEL);
+	if (!ctxdata)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&ctxdata->sess_list);
+	INIT_LIST_HEAD(&shmctx.shmdata_list);
+
+	ctx->data = ctxdata;
+	return 0;
+}
+
+static void release_session(struct amdtee_session *sess)
+{
+	int i = 0;
+
+	/* Close any open session */
+	for (i = 0; i < TEE_NUM_SESSIONS; ++i) {
+		/* Check if session entry 'i' is valid */
+		if (!test_bit(i, sess->sess_mask))
+			continue;
+
+		handle_close_session(sess->ta_handle, sess->session_info[i]);
+	}
+
+	/* Unload Trusted Application once all sessions are closed */
+	handle_unload_ta(sess->ta_handle);
+	kfree(sess);
+}
+
+static void amdtee_release(struct tee_context *ctx)
+{
+	struct amdtee_context_data *ctxdata = ctx->data;
+
+	if (!ctxdata)
+		return;
+
+	while (true) {
+		struct amdtee_session *sess;
+
+		sess = list_first_entry_or_null(&ctxdata->sess_list,
+						struct amdtee_session,
+						list_node);
+
+		if (!sess)
+			break;
+
+		list_del(&sess->list_node);
+		release_session(sess);
+	}
+	kfree(ctxdata);
+
+	ctx->data = NULL;
+}
+
+/**
+ * alloc_session() - Allocate a session structure
+ * @ctxdata:    TEE Context data structure
+ * @session:    Session ID for which 'struct amdtee_session' structure is to be
+ *              allocated.
+ *
+ * Scans the TEE context's session list to check if TA is already loaded in to
+ * TEE. If yes, returns the 'session' structure for that TA. Else allocates,
+ * initializes a new 'session' structure and adds it to context's session list.
+ *
+ * The caller must hold a mutex.
+ *
+ * Returns:
+ * 'struct amdtee_session *' on success and NULL on failure.
+ */
+static struct amdtee_session *alloc_session(struct amdtee_context_data *ctxdata,
+					    u32 session)
+{
+	struct amdtee_session *sess;
+	u32 ta_handle = get_ta_handle(session);
+
+	/* Scan session list to check if TA is already loaded in to TEE */
+	list_for_each_entry(sess, &ctxdata->sess_list, list_node)
+		if (sess->ta_handle == ta_handle) {
+			kref_get(&sess->refcount);
+			return sess;
+		}
+
+	/* Allocate a new session and add to list */
+	sess = kzalloc(sizeof(*sess), GFP_KERNEL);
+	if (sess) {
+		sess->ta_handle = ta_handle;
+		kref_init(&sess->refcount);
+		spin_lock_init(&sess->lock);
+		list_add(&sess->list_node, &ctxdata->sess_list);
+	}
+
+	return sess;
+}
+
+/* Requires mutex to be held */
+static struct amdtee_session *find_session(struct amdtee_context_data *ctxdata,
+					   u32 session)
+{
+	u32 ta_handle = get_ta_handle(session);
+	u32 index = get_session_index(session);
+	struct amdtee_session *sess;
+
+	list_for_each_entry(sess, &ctxdata->sess_list, list_node)
+		if (ta_handle == sess->ta_handle &&
+		    test_bit(index, sess->sess_mask))
+			return sess;
+
+	return NULL;
+}
+
+u32 get_buffer_id(struct tee_shm *shm)
+{
+	u32 buf_id = 0;
+	struct amdtee_shm_data *shmdata;
+
+	list_for_each_entry(shmdata, &shmctx.shmdata_list, shm_node)
+		if (shmdata->kaddr == shm->kaddr) {
+			buf_id = shmdata->buf_id;
+			break;
+		}
+
+	return buf_id;
+}
+
+static DEFINE_MUTEX(drv_mutex);
+static int copy_ta_binary(struct tee_context *ctx, void *ptr, void **ta,
+			  size_t *ta_size)
+{
+	const struct firmware *fw;
+	char fw_name[TA_PATH_MAX];
+	struct {
+		u32 lo;
+		u16 mid;
+		u16 hi_ver;
+		u8 seq_n[8];
+	} *uuid = ptr;
+	int n = 0, rc = 0;
+
+	n = snprintf(fw_name, TA_PATH_MAX,
+		     "%s/%08x-%04x-%04x-%02x%02x%02x%02x%02x%02x%02x%02x.bin",
+		     TA_LOAD_PATH, uuid->lo, uuid->mid, uuid->hi_ver,
+		     uuid->seq_n[0], uuid->seq_n[1],
+		     uuid->seq_n[2], uuid->seq_n[3],
+		     uuid->seq_n[4], uuid->seq_n[5],
+		     uuid->seq_n[6], uuid->seq_n[7]);
+	if (n < 0 || n >= TA_PATH_MAX) {
+		pr_err("failed to get firmware name\n");
+		return -EINVAL;
+	}
+
+	mutex_lock(&drv_mutex);
+	n = request_firmware(&fw, fw_name, &ctx->teedev->dev);
+	if (n) {
+		pr_err("failed to load firmware %s\n", fw_name);
+		rc = -ENOMEM;
+		goto unlock;
+	}
+
+	*ta_size = roundup(fw->size, PAGE_SIZE);
+	*ta = (void *)__get_free_pages(GFP_KERNEL, get_order(*ta_size));
+	if (IS_ERR(*ta)) {
+		pr_err("%s: get_free_pages failed 0x%llx\n", __func__,
+		       (u64)*ta);
+		rc = -ENOMEM;
+		goto rel_fw;
+	}
+
+	memcpy(*ta, fw->data, fw->size);
+rel_fw:
+	release_firmware(fw);
+unlock:
+	mutex_unlock(&drv_mutex);
+	return rc;
+}
+
+int amdtee_open_session(struct tee_context *ctx,
+			struct tee_ioctl_open_session_arg *arg,
+			struct tee_param *param)
+{
+	struct amdtee_context_data *ctxdata = ctx->data;
+	struct amdtee_session *sess = NULL;
+	u32 session_info;
+	void *ta = NULL;
+	size_t ta_size;
+	int rc = 0, i;
+
+	if (arg->clnt_login != TEE_IOCTL_LOGIN_PUBLIC) {
+		pr_err("unsupported client login method\n");
+		return -EINVAL;
+	}
+
+	rc = copy_ta_binary(ctx, &arg->uuid[0], &ta, &ta_size);
+	if (rc) {
+		pr_err("failed to copy TA binary\n");
+		return rc;
+	}
+
+	/* Load the TA binary into TEE environment */
+	handle_load_ta(ta, ta_size, arg);
+	if (arg->ret == TEEC_SUCCESS) {
+		mutex_lock(&session_list_mutex);
+		sess = alloc_session(ctxdata, arg->session);
+		mutex_unlock(&session_list_mutex);
+	}
+
+	if (arg->ret != TEEC_SUCCESS)
+		goto out;
+
+	if (!sess) {
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	/* Find an empty session index for the given TA */
+	spin_lock(&sess->lock);
+	i = find_first_zero_bit(sess->sess_mask, TEE_NUM_SESSIONS);
+	if (i < TEE_NUM_SESSIONS)
+		set_bit(i, sess->sess_mask);
+	spin_unlock(&sess->lock);
+
+	if (i >= TEE_NUM_SESSIONS) {
+		pr_err("reached maximum session count %d\n", TEE_NUM_SESSIONS);
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	/* Open session with loaded TA */
+	handle_open_session(arg, &session_info, param);
+
+	if (arg->ret == TEEC_SUCCESS) {
+		sess->session_info[i] = session_info;
+		set_session_id(sess->ta_handle, i, &arg->session);
+	} else {
+		pr_err("open_session failed %d\n", arg->ret);
+		spin_lock(&sess->lock);
+		clear_bit(i, sess->sess_mask);
+		spin_unlock(&sess->lock);
+	}
+out:
+	free_pages((u64)ta, get_order(ta_size));
+	return rc;
+}
+
+static void destroy_session(struct kref *ref)
+{
+	struct amdtee_session *sess = container_of(ref, struct amdtee_session,
+						   refcount);
+
+	/* Unload the TA from TEE */
+	handle_unload_ta(sess->ta_handle);
+	mutex_lock(&session_list_mutex);
+	list_del(&sess->list_node);
+	mutex_unlock(&session_list_mutex);
+	kfree(sess);
+}
+
+int amdtee_close_session(struct tee_context *ctx, u32 session)
+{
+	struct amdtee_context_data *ctxdata = ctx->data;
+	u32 i, ta_handle, session_info;
+	struct amdtee_session *sess;
+
+	pr_debug("%s: sid = 0x%x\n", __func__, session);
+
+	/*
+	 * Check that the session is valid and clear the session
+	 * usage bit
+	 */
+	mutex_lock(&session_list_mutex);
+	sess = find_session(ctxdata, session);
+	if (sess) {
+		ta_handle = get_ta_handle(session);
+		i = get_session_index(session);
+		session_info = sess->session_info[i];
+		spin_lock(&sess->lock);
+		clear_bit(i, sess->sess_mask);
+		spin_unlock(&sess->lock);
+	}
+	mutex_unlock(&session_list_mutex);
+
+	if (!sess)
+		return -EINVAL;
+
+	/* Close the session */
+	handle_close_session(ta_handle, session_info);
+
+	kref_put(&sess->refcount, destroy_session);
+
+	return 0;
+}
+
+int amdtee_map_shmem(struct tee_shm *shm)
+{
+	struct shmem_desc shmem;
+	struct amdtee_shm_data *shmnode;
+	int rc, count;
+	u32 buf_id;
+
+	if (!shm)
+		return -EINVAL;
+
+	shmnode = kmalloc(sizeof(*shmnode), GFP_KERNEL);
+	if (!shmnode)
+		return -ENOMEM;
+
+	count = 1;
+	shmem.kaddr = shm->kaddr;
+	shmem.size = shm->size;
+
+	/*
+	 * Send a MAP command to TEE and get the corresponding
+	 * buffer Id
+	 */
+	rc = handle_map_shmem(count, &shmem, &buf_id);
+	if (rc) {
+		pr_err("map_shmem failed: ret = %d\n", rc);
+		kfree(shmnode);
+		return rc;
+	}
+
+	shmnode->kaddr = shm->kaddr;
+	shmnode->buf_id = buf_id;
+	list_add(&shmnode->shm_node, &shmctx.shmdata_list);
+
+	pr_debug("buf_id :[%x] kaddr[%p]\n", shmnode->buf_id, shmnode->kaddr);
+
+	return 0;
+}
+
+void amdtee_unmap_shmem(struct tee_shm *shm)
+{
+	u32 buf_id;
+	struct amdtee_shm_data *shmnode = NULL;
+
+	if (!shm)
+		return;
+
+	buf_id = get_buffer_id(shm);
+	/* Unmap the shared memory from TEE */
+	handle_unmap_shmem(buf_id);
+
+	list_for_each_entry(shmnode, &shmctx.shmdata_list, shm_node)
+		if (buf_id == shmnode->buf_id) {
+			list_del(&shmnode->shm_node);
+			kfree(shmnode);
+			break;
+		}
+}
+
+int amdtee_invoke_func(struct tee_context *ctx,
+		       struct tee_ioctl_invoke_arg *arg,
+		       struct tee_param *param)
+{
+	struct amdtee_context_data *ctxdata = ctx->data;
+	struct amdtee_session *sess;
+	u32 i, session_info;
+
+	/* Check that the session is valid */
+	mutex_lock(&session_list_mutex);
+	sess = find_session(ctxdata, arg->session);
+	if (sess) {
+		i = get_session_index(arg->session);
+		session_info = sess->session_info[i];
+	}
+	mutex_unlock(&session_list_mutex);
+
+	if (!sess)
+		return -EINVAL;
+
+	handle_invoke_cmd(arg, session_info, param);
+
+	return 0;
+}
+
+int amdtee_cancel_req(struct tee_context *ctx, u32 cancel_id, u32 session)
+{
+	return -EINVAL;
+}
+
+static const struct tee_driver_ops amdtee_ops = {
+	.get_version = amdtee_get_version,
+	.open = amdtee_open,
+	.release = amdtee_release,
+	.open_session = amdtee_open_session,
+	.close_session = amdtee_close_session,
+	.invoke_func = amdtee_invoke_func,
+	.cancel_req = amdtee_cancel_req,
+};
+
+static const struct tee_desc amdtee_desc = {
+	.name = DRIVER_NAME "-clnt",
+	.ops = &amdtee_ops,
+	.owner = THIS_MODULE,
+};
+
+static int __init amdtee_driver_init(void)
+{
+	struct amdtee *amdtee = NULL;
+	struct tee_device *teedev;
+	struct tee_shm_pool *pool = ERR_PTR(-EINVAL);
+	int rc;
+
+	drv_data = kzalloc(sizeof(*drv_data), GFP_KERNEL);
+	if (IS_ERR(drv_data))
+		return -ENOMEM;
+
+	amdtee = kzalloc(sizeof(*amdtee), GFP_KERNEL);
+	if (IS_ERR(amdtee)) {
+		rc = -ENOMEM;
+		goto err_kfree_drv_data;
+	}
+
+	pool = amdtee_config_shm();
+	if (IS_ERR(pool)) {
+		pr_err("shared pool configuration error\n");
+		rc = PTR_ERR(pool);
+		goto err_kfree_amdtee;
+	}
+
+	teedev = tee_device_alloc(&amdtee_desc, NULL, pool, amdtee);
+	if (IS_ERR(teedev)) {
+		rc = PTR_ERR(teedev);
+		goto err;
+	}
+	amdtee->teedev = teedev;
+
+	rc = tee_device_register(amdtee->teedev);
+	if (rc)
+		goto err;
+
+	amdtee->pool = pool;
+
+	drv_data->amdtee = amdtee;
+
+	pr_info("amd-tee driver initialization successful\n");
+	return 0;
+
+err:
+	tee_device_unregister(amdtee->teedev);
+	if (pool)
+		tee_shm_pool_free(pool);
+
+err_kfree_amdtee:
+	kfree(amdtee);
+
+err_kfree_drv_data:
+	kfree(drv_data);
+	drv_data = NULL;
+
+	pr_err("amd-tee driver initialization failed\n");
+	return rc;
+}
+module_init(amdtee_driver_init);
+
+static void __exit amdtee_driver_exit(void)
+{
+	struct amdtee *amdtee;
+
+	if (!drv_data || !drv_data->amdtee)
+		return;
+
+	amdtee = drv_data->amdtee;
+
+	tee_device_unregister(amdtee->teedev);
+	tee_shm_pool_free(amdtee->pool);
+}
+module_exit(amdtee_driver_exit);
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION("AMD-TEE driver");
+MODULE_VERSION("1.0");
+MODULE_LICENSE("Dual MIT/GPL");

drivers/tee/amdtee/shm_pool.c

+// SPDX-License-Identifier: MIT
+/*
+ * Copyright 2019 Advanced Micro Devices, Inc.
+ */
+
+#include <linux/slab.h>
+#include <linux/tee_drv.h>
+#include <linux/psp-sev.h>
+#include "amdtee_private.h"
+
+static int pool_op_alloc(struct tee_shm_pool_mgr *poolm, struct tee_shm *shm,
+			 size_t size)
+{
+	unsigned int order = get_order(size);
+	unsigned long va;
+	int rc;
+
+	va = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
+	if (!va)
+		return -ENOMEM;
+
+	shm->kaddr = (void *)va;
+	shm->paddr = __psp_pa((void *)va);
+	shm->size = PAGE_SIZE << order;
+
+	/* Map the allocated memory in to TEE */
+	rc = amdtee_map_shmem(shm);
+	if (rc) {
+		free_pages(va, order);
+		shm->kaddr = NULL;
+		return rc;
+	}
+
+	return 0;
+}
+
+static void pool_op_free(struct tee_shm_pool_mgr *poolm, struct tee_shm *shm)
+{
+	/* Unmap the shared memory from TEE */
+	amdtee_unmap_shmem(shm);
+	free_pages((unsigned long)shm->kaddr, get_order(shm->size));
+	shm->kaddr = NULL;
+}
+
+static void pool_op_destroy_poolmgr(struct tee_shm_pool_mgr *poolm)
+{
+	kfree(poolm);
+}
+
+static const struct tee_shm_pool_mgr_ops pool_ops = {
+	.alloc = pool_op_alloc,
+	.free = pool_op_free,
+	.destroy_poolmgr = pool_op_destroy_poolmgr,
+};
+
+static struct tee_shm_pool_mgr *pool_mem_mgr_alloc(void)
+{
+	struct tee_shm_pool_mgr *mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
+
+	if (!mgr)
+		return ERR_PTR(-ENOMEM);
+
+	mgr->ops = &pool_ops;
+
+	return mgr;
+}
+
+struct tee_shm_pool *amdtee_config_shm(void)
+{
+	struct tee_shm_pool_mgr *priv_mgr;
+	struct tee_shm_pool_mgr *dmabuf_mgr;
+	void *rc;
+
+	rc = pool_mem_mgr_alloc();
+	if (IS_ERR(rc))
+		return rc;
+	priv_mgr = rc;
+
+	rc = pool_mem_mgr_alloc();
+	if (IS_ERR(rc)) {
+		tee_shm_pool_mgr_destroy(priv_mgr);
+		return rc;
+	}
+	dmabuf_mgr = rc;
+
+	rc = tee_shm_pool_alloc(priv_mgr, dmabuf_mgr);
+	if (IS_ERR(rc)) {
+		tee_shm_pool_mgr_destroy(priv_mgr);
+		tee_shm_pool_mgr_destroy(dmabuf_mgr);
+	}
+
+	return rc;
+}

include/uapi/linux/tee.h

@@ -56,6 +56,7 @@
  * TEE Implementation ID
  */
 #define TEE_IMPL_ID_OPTEE	1
+#define TEE_IMPL_ID_AMDTEE	2
 
 /*
  * OP-TEE specific capabilities