Re: [RFC PATCH 2/2] tee: add AMD-TEE driver

Thomas, Rijo-john
2019-11-26T13:01:40Z

Hi Jens,

On 05/11/19 8:58 PM, Jens Wiklander wrote:
> Hi Rijo,
>
> On Wed, Oct 23, 2019 at 11:31:01AM +0000, Thomas, Rijo-john wrote:
>> 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
>>
>> Signed-off-by: Rijo Thomas <Rijo-john.Thomas@amd.com>
>> Signed-off-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
>> ---
>> drivers/tee/Kconfig | 2 +-
>> drivers/tee/Makefile | 1 +
>> drivers/tee/amdtee/Kconfig | 8 +
>> drivers/tee/amdtee/Makefile | 5 +
>> drivers/tee/amdtee/amdtee_if.h | 183 +++++++++++++
>> drivers/tee/amdtee/amdtee_private.h | 159 +++++++++++
>> drivers/tee/amdtee/call.c | 370 ++++++++++++++++++++++++++
>> drivers/tee/amdtee/core.c | 510 ++++++++++++++++++++++++++++++++++++
>> drivers/tee/amdtee/shm_pool.c | 130 +++++++++
>> include/uapi/linux/tee.h | 1 +
>> 10 files changed, 1368 insertions(+), 1 deletion(-)
>> create mode 100644 drivers/tee/amdtee/Kconfig
>> create mode 100644 drivers/tee/amdtee/Makefile
>> create mode 100644 drivers/tee/amdtee/amdtee_if.h
>> create mode 100644 drivers/tee/amdtee/amdtee_private.h
>> create mode 100644 drivers/tee/amdtee/call.c
>> create mode 100644 drivers/tee/amdtee/core.c
>> create mode 100644 drivers/tee/amdtee/shm_pool.c
>>
>> diff --git a/drivers/tee/Kconfig b/drivers/tee/Kconfig
>> index 4f3197d..8da63f3 100644
>> --- a/drivers/tee/Kconfig
>> +++ b/drivers/tee/Kconfig
>> @@ -14,7 +14,7 @@ if TEE
>> menu "TEE drivers"
>>
>> source "drivers/tee/optee/Kconfig"
>> -
>> +source "drivers/tee/amdtee/Kconfig"
>> endmenu
>>
>> endif
>> diff --git a/drivers/tee/Makefile b/drivers/tee/Makefile
>> index 21f51fd..68da044 100644
>> --- a/drivers/tee/Makefile
>> +++ b/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/
>> diff --git a/drivers/tee/amdtee/Kconfig b/drivers/tee/amdtee/Kconfig
>> new file mode 100644
>> index 0000000..4e32b64
>> --- /dev/null
>> +++ b/drivers/tee/amdtee/Kconfig
>> @@ -0,0 +1,8 @@
>> +# 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.
>> diff --git a/drivers/tee/amdtee/Makefile b/drivers/tee/amdtee/Makefile
>> new file mode 100644
>> index 0000000..ff14852
>> --- /dev/null
>> +++ b/drivers/tee/amdtee/Makefile
>> @@ -0,0 +1,5 @@
>> +# SPDX-License-Identifier: MIT
>> +obj-$(CONFIG_AMDTEE) += amdtee.o
>> +amdtee-objs += core.o
>> +amdtee-objs += call.o
>> +amdtee-objs += shm_pool.o
>> diff --git a/drivers/tee/amdtee/amdtee_if.h b/drivers/tee/amdtee/amdtee_if.h
>> new file mode 100644
>> index 0000000..ff48c3e
>> --- /dev/null
>> +++ b/drivers/tee/amdtee/amdtee_if.h
>> @@ -0,0 +1,183 @@
>> +/* 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
>
> These are the same as TEE_IOCTL_PARAM_ATTR_TYPE_* in include/uapi/linux/tee.h
> except that TEE_OP_PARAM_TYPE_INVALID is added. The latter is not defined in
> the GP spec.
>

We added TEE_OP_PARAM_TYPE_INVALID to avoid magic numbers in code. The rest are,
as you said, based on GP spec.

Do you want us to use the macros (TEE_IOCTL_PARAM_ATTR_TYPE_*) defined in
include/uapi/linux/tee.h instead of redefining them?

>> +
>> +#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*/
>> diff --git a/drivers/tee/amdtee/amdtee_private.h b/drivers/tee/amdtee/amdtee_private.h
>> new file mode 100644
>> index 0000000..d7f798c
>> --- /dev/null
>> +++ b/drivers/tee/amdtee/amdtee_private.h
>> @@ -0,0 +1,159 @@
>> +/* 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*/
>> diff --git a/drivers/tee/amdtee/call.c b/drivers/tee/amdtee/call.c
>> new file mode 100644
>> index 0000000..e87b0d1
>> --- /dev/null
>> +++ b/drivers/tee/amdtee/call.c
>> @@ -0,0 +1,370 @@
>> +// 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 "../tee_private.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->param_types |= ((tee[i].attr & 0xF) << i * 4);
>
> tee[i].attr holds values defined by TEE_IOCTL_PARAM_ATTR_* in
> include/uapi/linux/tee.h so it can currently be 9 bits wide, by masking
> out the lower 4 bits you accept some invalid values
>

Agreed, with 9 bits wide attribute value, current code will not work as
expected. I shall correct this in next patch revision.

>> +
>> + 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)
>> + 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[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;
>> +}
>> diff --git a/drivers/tee/amdtee/core.c b/drivers/tee/amdtee/core.c
>> new file mode 100644
>> index 0000000..b184463
>> --- /dev/null
>> +++ b/drivers/tee/amdtee/core.c
>> @@ -0,0 +1,510 @@
>> +// 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);
>> +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;
>
> It seems that this driver assumes that there's a TEE to talk to if this
> function is called. What is the expected behavoir if there's no TEE
> available?
>

The expected behavior if there is no TEE is: amdtee_driver_init() should
fail with -ENODEV. The driver should check for the availability of TEE on
the platform before doing shared pool configuration followed by
tee_device_alloc() and tee_device_register().

I agree in the current design, the driver assumes that there is a TEE to
talk to. This will be fixed in next patch revision.

>> +
>> + 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");
>> diff --git a/drivers/tee/amdtee/shm_pool.c b/drivers/tee/amdtee/shm_pool.c
>> new file mode 100644
>> index 0000000..10392d6
>> --- /dev/null
>> +++ b/drivers/tee/amdtee/shm_pool.c
>> @@ -0,0 +1,130 @@
>> +// 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 "../tee_private.h"
>
> Drivers aren't supposed to need to include this file, if there's
> something needed by drivers we could consider moving that part to
> <linux/tee_drv.h>
>

Sure, I will remove references to tee_private.h in driver code.
The driver needs access to : "struct device dev" member of "struct tee_device"
Can you please add a helper function to access this device structure?
The 'struct device dev' is passed as an argument to request_firmware().
Please refer file: drivers/tee/amdtee/core.c for usage.

>> +#include "amdtee_private.h"
>> +
>> +static int pool_op_alloc(struct tee_shm_pool_mgr *poolm, struct tee_shm *shm,
>> + size_t size)
>> +{
>> + unsigned long va;
>> + int min_alloc_order = *(int *)poolm->private_data;
>> + size_t s = roundup(size, 1 << min_alloc_order);
>> + int rc;
>> +
>> + va = __get_free_pages(GFP_KERNEL, get_order(s));
>> + if (!va)
>> + return -ENOMEM;
>> +
>> + memset((void *)va, 0, s);
>> + shm->kaddr = (void *)va;
>> + shm->paddr = __psp_pa((void *)va);
>> + shm->size = s;
>> +
>> + /* Map the allocated memory in to TEE */
>> + rc = amdtee_map_shmem(shm);
>> + if (rc) {
>> + free_pages(va, get_order(s));
>> + 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)
>> +{
>> + if (poolm && poolm->private_data) {
>> + kfree(poolm->private_data);
>> + poolm->private_data = NULL;
>> + }
>> +
>> + 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 int pool_mem_mgr_init(struct tee_shm_pool_mgr *mgr, int min_alloc_order)
>> +{
>> + int *order;
>> +
>> + order = kmalloc(sizeof(min_alloc_order), GFP_KERNEL);
>> + if (!order)
>> + return -ENOMEM;
>> +
>> + *order = min_alloc_order;
>> + mgr->private_data = order;
>> + mgr->ops = &pool_ops;
>> + return 0;
>> +}
>> +
>> +struct tee_shm_pool *amdtee_config_shm(void)
>> +{
>> + struct tee_shm_pool *pool = NULL;
>> + struct tee_shm_pool_mgr *priv_mgr;
>> + struct tee_shm_pool_mgr *dmabuf_mgr;
>> + int ret;
>> +
>> + pool = kzalloc(sizeof(*pool), GFP_KERNEL);
>
> Why isn't tee_shm_pool_alloc() used instead?
>

That's a good question!
tee_shm_pool_alloc() was not available initally, and was added later to tee subsystem.
I shall update the driver to use this API in my next patch revision.

>> + if (!pool) {
>> + ret = -ENOMEM;
>> + goto err;
>> + }
>> +
>> + priv_mgr = kzalloc(sizeof(*priv_mgr), GFP_KERNEL);
>> + if (!priv_mgr) {
>> + ret = -ENOMEM;
>> + goto err;
>> + }
>> +
>> + dmabuf_mgr = kzalloc(sizeof(*dmabuf_mgr), GFP_KERNEL);
>> + if (!dmabuf_mgr) {
>> + ret = -ENOMEM;
>> + goto err;
>> + }
>> +
>> + pool->private_mgr = priv_mgr;
>> + pool->dma_buf_mgr = dmabuf_mgr;
>> + /*
>> + * Initialize memory manager for driver private shared memory
>> + */
>> + ret = pool_mem_mgr_init(pool->private_mgr, 3 /* 8 byte aligned */);
>> + if (ret)
>> + goto err;
>> +
>> + /*
>> + * Initialize memory manager for dma_buf shared memory
>> + */
>> + ret = pool_mem_mgr_init(pool->dma_buf_mgr, PAGE_SHIFT);
>> + if (ret)
>> + goto err;
>> +
>> + return pool;
>> +err:
>> + if (ret == -ENOMEM)
>> + pr_err("%s: failed to configure shared memory pool\n",
>> + __func__);
>> + if (pool && pool->private_mgr->private_data)
>> + kfree(pool->private_mgr->private_data);
>> + kfree(pool);
>> + kfree(priv_mgr);
>> + kfree(dmabuf_mgr);
>> + return ERR_PTR(ret);
>> +}
>> diff --git a/include/uapi/linux/tee.h b/include/uapi/linux/tee.h
>> index 4b9eb06..6596f3a 100644
>> --- a/include/uapi/linux/tee.h
>> +++ b/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
>> --
>> 1.9.1
>>
>
> Cheers,
> Jens
>

Thanks,
Rijo