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v6.2
  1// SPDX-License-Identifier: MIT
  2/*
  3 * AMD Trusted Execution Environment (TEE) interface
  4 *
  5 * Author: Rijo Thomas <Rijo-john.Thomas@amd.com>
  6 * Author: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
  7 *
  8 * Copyright (C) 2019,2021 Advanced Micro Devices, Inc.
  9 */
 10
 
 11#include <linux/types.h>
 12#include <linux/mutex.h>
 13#include <linux/delay.h>
 14#include <linux/slab.h>
 15#include <linux/gfp.h>
 16#include <linux/psp-sev.h>
 17#include <linux/psp-tee.h>
 18
 19#include "psp-dev.h"
 20#include "tee-dev.h"
 21
 22static bool psp_dead;
 23
 24static int tee_alloc_ring(struct psp_tee_device *tee, int ring_size)
 25{
 26	struct ring_buf_manager *rb_mgr = &tee->rb_mgr;
 27	void *start_addr;
 28
 29	if (!ring_size)
 30		return -EINVAL;
 31
 32	/* We need actual physical address instead of DMA address, since
 33	 * Trusted OS running on AMD Secure Processor will map this region
 34	 */
 35	start_addr = (void *)__get_free_pages(GFP_KERNEL, get_order(ring_size));
 36	if (!start_addr)
 37		return -ENOMEM;
 38
 39	memset(start_addr, 0x0, ring_size);
 40	rb_mgr->ring_start = start_addr;
 41	rb_mgr->ring_size = ring_size;
 42	rb_mgr->ring_pa = __psp_pa(start_addr);
 43	mutex_init(&rb_mgr->mutex);
 44
 45	return 0;
 46}
 47
 48static void tee_free_ring(struct psp_tee_device *tee)
 49{
 50	struct ring_buf_manager *rb_mgr = &tee->rb_mgr;
 51
 52	if (!rb_mgr->ring_start)
 53		return;
 54
 55	free_pages((unsigned long)rb_mgr->ring_start,
 56		   get_order(rb_mgr->ring_size));
 57
 58	rb_mgr->ring_start = NULL;
 59	rb_mgr->ring_size = 0;
 60	rb_mgr->ring_pa = 0;
 61	mutex_destroy(&rb_mgr->mutex);
 62}
 63
 64static int tee_wait_cmd_poll(struct psp_tee_device *tee, unsigned int timeout,
 65			     unsigned int *reg)
 66{
 67	/* ~10ms sleep per loop => nloop = timeout * 100 */
 68	int nloop = timeout * 100;
 69
 70	while (--nloop) {
 71		*reg = ioread32(tee->io_regs + tee->vdata->cmdresp_reg);
 72		if (*reg & PSP_CMDRESP_RESP)
 73			return 0;
 74
 75		usleep_range(10000, 10100);
 76	}
 77
 78	dev_err(tee->dev, "tee: command timed out, disabling PSP\n");
 79	psp_dead = true;
 80
 81	return -ETIMEDOUT;
 82}
 83
 84static
 85struct tee_init_ring_cmd *tee_alloc_cmd_buffer(struct psp_tee_device *tee)
 86{
 87	struct tee_init_ring_cmd *cmd;
 88
 89	cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
 90	if (!cmd)
 91		return NULL;
 92
 93	cmd->hi_addr = upper_32_bits(tee->rb_mgr.ring_pa);
 94	cmd->low_addr = lower_32_bits(tee->rb_mgr.ring_pa);
 95	cmd->size = tee->rb_mgr.ring_size;
 96
 97	dev_dbg(tee->dev, "tee: ring address: high = 0x%x low = 0x%x size = %u\n",
 98		cmd->hi_addr, cmd->low_addr, cmd->size);
 99
100	return cmd;
101}
102
103static inline void tee_free_cmd_buffer(struct tee_init_ring_cmd *cmd)
104{
105	kfree(cmd);
106}
107
108static int tee_init_ring(struct psp_tee_device *tee)
109{
110	int ring_size = MAX_RING_BUFFER_ENTRIES * sizeof(struct tee_ring_cmd);
111	struct tee_init_ring_cmd *cmd;
112	phys_addr_t cmd_buffer;
113	unsigned int reg;
114	int ret;
115
116	BUILD_BUG_ON(sizeof(struct tee_ring_cmd) != 1024);
117
118	ret = tee_alloc_ring(tee, ring_size);
119	if (ret) {
120		dev_err(tee->dev, "tee: ring allocation failed %d\n", ret);
121		return ret;
122	}
123
124	tee->rb_mgr.wptr = 0;
125
126	cmd = tee_alloc_cmd_buffer(tee);
127	if (!cmd) {
128		tee_free_ring(tee);
129		return -ENOMEM;
130	}
131
132	cmd_buffer = __psp_pa((void *)cmd);
133
134	/* Send command buffer details to Trusted OS by writing to
135	 * CPU-PSP message registers
136	 */
137
138	iowrite32(lower_32_bits(cmd_buffer),
139		  tee->io_regs + tee->vdata->cmdbuff_addr_lo_reg);
140	iowrite32(upper_32_bits(cmd_buffer),
141		  tee->io_regs + tee->vdata->cmdbuff_addr_hi_reg);
142	iowrite32(TEE_RING_INIT_CMD,
143		  tee->io_regs + tee->vdata->cmdresp_reg);
144
145	ret = tee_wait_cmd_poll(tee, TEE_DEFAULT_TIMEOUT, &reg);
146	if (ret) {
147		dev_err(tee->dev, "tee: ring init command timed out\n");
148		tee_free_ring(tee);
 
149		goto free_buf;
150	}
151
152	if (reg & PSP_CMDRESP_ERR_MASK) {
153		dev_err(tee->dev, "tee: ring init command failed (%#010x)\n",
154			reg & PSP_CMDRESP_ERR_MASK);
155		tee_free_ring(tee);
156		ret = -EIO;
157	}
158
159free_buf:
160	tee_free_cmd_buffer(cmd);
161
162	return ret;
163}
164
165static void tee_destroy_ring(struct psp_tee_device *tee)
166{
167	unsigned int reg;
168	int ret;
169
170	if (!tee->rb_mgr.ring_start)
171		return;
172
173	if (psp_dead)
174		goto free_ring;
175
176	iowrite32(TEE_RING_DESTROY_CMD,
177		  tee->io_regs + tee->vdata->cmdresp_reg);
178
179	ret = tee_wait_cmd_poll(tee, TEE_DEFAULT_TIMEOUT, &reg);
180	if (ret) {
181		dev_err(tee->dev, "tee: ring destroy command timed out\n");
182	} else if (reg & PSP_CMDRESP_ERR_MASK) {
183		dev_err(tee->dev, "tee: ring destroy command failed (%#010x)\n",
184			reg & PSP_CMDRESP_ERR_MASK);
 
185	}
186
187free_ring:
188	tee_free_ring(tee);
189}
190
191int tee_dev_init(struct psp_device *psp)
192{
193	struct device *dev = psp->dev;
194	struct psp_tee_device *tee;
195	int ret;
196
197	ret = -ENOMEM;
198	tee = devm_kzalloc(dev, sizeof(*tee), GFP_KERNEL);
199	if (!tee)
200		goto e_err;
201
202	psp->tee_data = tee;
203
204	tee->dev = dev;
205	tee->psp = psp;
206
207	tee->io_regs = psp->io_regs;
208
209	tee->vdata = (struct tee_vdata *)psp->vdata->tee;
210	if (!tee->vdata) {
211		ret = -ENODEV;
212		dev_err(dev, "tee: missing driver data\n");
213		goto e_err;
214	}
215
216	ret = tee_init_ring(tee);
217	if (ret) {
218		dev_err(dev, "tee: failed to init ring buffer\n");
219		goto e_err;
220	}
221
222	dev_notice(dev, "tee enabled\n");
223
224	return 0;
225
226e_err:
227	psp->tee_data = NULL;
228
229	dev_notice(dev, "tee initialization failed\n");
230
231	return ret;
232}
233
234void tee_dev_destroy(struct psp_device *psp)
235{
236	struct psp_tee_device *tee = psp->tee_data;
237
238	if (!tee)
239		return;
240
241	tee_destroy_ring(tee);
242}
243
244static int tee_submit_cmd(struct psp_tee_device *tee, enum tee_cmd_id cmd_id,
245			  void *buf, size_t len, struct tee_ring_cmd **resp)
246{
247	struct tee_ring_cmd *cmd;
248	int nloop = 1000, ret = 0;
249	u32 rptr;
250
251	*resp = NULL;
252
253	mutex_lock(&tee->rb_mgr.mutex);
254
255	/* Loop until empty entry found in ring buffer */
256	do {
257		/* Get pointer to ring buffer command entry */
258		cmd = (struct tee_ring_cmd *)
259			(tee->rb_mgr.ring_start + tee->rb_mgr.wptr);
260
261		rptr = ioread32(tee->io_regs + tee->vdata->ring_rptr_reg);
262
263		/* Check if ring buffer is full or command entry is waiting
264		 * for response from TEE
265		 */
266		if (!(tee->rb_mgr.wptr + sizeof(struct tee_ring_cmd) == rptr ||
267		      cmd->flag == CMD_WAITING_FOR_RESPONSE))
268			break;
269
270		dev_dbg(tee->dev, "tee: ring buffer full. rptr = %u wptr = %u\n",
271			rptr, tee->rb_mgr.wptr);
272
273		/* Wait if ring buffer is full or TEE is processing data */
274		mutex_unlock(&tee->rb_mgr.mutex);
275		schedule_timeout_interruptible(msecs_to_jiffies(10));
276		mutex_lock(&tee->rb_mgr.mutex);
277
278	} while (--nloop);
279
280	if (!nloop &&
281	    (tee->rb_mgr.wptr + sizeof(struct tee_ring_cmd) == rptr ||
282	     cmd->flag == CMD_WAITING_FOR_RESPONSE)) {
283		dev_err(tee->dev, "tee: ring buffer full. rptr = %u wptr = %u response flag %u\n",
284			rptr, tee->rb_mgr.wptr, cmd->flag);
285		ret = -EBUSY;
286		goto unlock;
287	}
288
289	/* Do not submit command if PSP got disabled while processing any
290	 * command in another thread
291	 */
292	if (psp_dead) {
293		ret = -EBUSY;
294		goto unlock;
295	}
296
297	/* Write command data into ring buffer */
298	cmd->cmd_id = cmd_id;
299	cmd->cmd_state = TEE_CMD_STATE_INIT;
300	memset(&cmd->buf[0], 0, sizeof(cmd->buf));
301	memcpy(&cmd->buf[0], buf, len);
302
303	/* Indicate driver is waiting for response */
304	cmd->flag = CMD_WAITING_FOR_RESPONSE;
305
306	/* Update local copy of write pointer */
307	tee->rb_mgr.wptr += sizeof(struct tee_ring_cmd);
308	if (tee->rb_mgr.wptr >= tee->rb_mgr.ring_size)
309		tee->rb_mgr.wptr = 0;
310
311	/* Trigger interrupt to Trusted OS */
312	iowrite32(tee->rb_mgr.wptr, tee->io_regs + tee->vdata->ring_wptr_reg);
313
314	/* The response is provided by Trusted OS in same
315	 * location as submitted data entry within ring buffer.
316	 */
317	*resp = cmd;
318
319unlock:
320	mutex_unlock(&tee->rb_mgr.mutex);
321
322	return ret;
323}
324
325static int tee_wait_cmd_completion(struct psp_tee_device *tee,
326				   struct tee_ring_cmd *resp,
327				   unsigned int timeout)
328{
329	/* ~1ms sleep per loop => nloop = timeout * 1000 */
330	int nloop = timeout * 1000;
331
332	while (--nloop) {
333		if (resp->cmd_state == TEE_CMD_STATE_COMPLETED)
334			return 0;
335
336		usleep_range(1000, 1100);
337	}
338
339	dev_err(tee->dev, "tee: command 0x%x timed out, disabling PSP\n",
340		resp->cmd_id);
341
342	psp_dead = true;
343
344	return -ETIMEDOUT;
345}
346
347int psp_tee_process_cmd(enum tee_cmd_id cmd_id, void *buf, size_t len,
348			u32 *status)
349{
350	struct psp_device *psp = psp_get_master_device();
351	struct psp_tee_device *tee;
352	struct tee_ring_cmd *resp;
353	int ret;
354
355	if (!buf || !status || !len || len > sizeof(resp->buf))
356		return -EINVAL;
357
358	*status = 0;
359
360	if (!psp || !psp->tee_data)
361		return -ENODEV;
362
363	if (psp_dead)
364		return -EBUSY;
365
366	tee = psp->tee_data;
367
368	ret = tee_submit_cmd(tee, cmd_id, buf, len, &resp);
369	if (ret)
370		return ret;
371
372	ret = tee_wait_cmd_completion(tee, resp, TEE_DEFAULT_TIMEOUT);
373	if (ret) {
374		resp->flag = CMD_RESPONSE_TIMEDOUT;
375		return ret;
376	}
377
378	memcpy(buf, &resp->buf[0], len);
379	*status = resp->status;
380
381	resp->flag = CMD_RESPONSE_COPIED;
382
383	return 0;
384}
385EXPORT_SYMBOL(psp_tee_process_cmd);
386
387int psp_check_tee_status(void)
388{
389	struct psp_device *psp = psp_get_master_device();
390
391	if (!psp || !psp->tee_data)
392		return -ENODEV;
393
394	return 0;
395}
396EXPORT_SYMBOL(psp_check_tee_status);
v6.9.4
  1// SPDX-License-Identifier: MIT
  2/*
  3 * AMD Trusted Execution Environment (TEE) interface
  4 *
  5 * Author: Rijo Thomas <Rijo-john.Thomas@amd.com>
  6 * Author: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
  7 *
  8 * Copyright (C) 2019,2021 Advanced Micro Devices, Inc.
  9 */
 10
 11#include <linux/bitfield.h>
 12#include <linux/types.h>
 13#include <linux/mutex.h>
 14#include <linux/delay.h>
 15#include <linux/slab.h>
 16#include <linux/gfp.h>
 17#include <linux/psp.h>
 18#include <linux/psp-tee.h>
 19
 20#include "psp-dev.h"
 21#include "tee-dev.h"
 22
 23static bool psp_dead;
 24
 25static int tee_alloc_ring(struct psp_tee_device *tee, int ring_size)
 26{
 27	struct ring_buf_manager *rb_mgr = &tee->rb_mgr;
 28	void *start_addr;
 29
 30	if (!ring_size)
 31		return -EINVAL;
 32
 33	/* We need actual physical address instead of DMA address, since
 34	 * Trusted OS running on AMD Secure Processor will map this region
 35	 */
 36	start_addr = (void *)__get_free_pages(GFP_KERNEL, get_order(ring_size));
 37	if (!start_addr)
 38		return -ENOMEM;
 39
 40	memset(start_addr, 0x0, ring_size);
 41	rb_mgr->ring_start = start_addr;
 42	rb_mgr->ring_size = ring_size;
 43	rb_mgr->ring_pa = __psp_pa(start_addr);
 44	mutex_init(&rb_mgr->mutex);
 45
 46	return 0;
 47}
 48
 49static void tee_free_ring(struct psp_tee_device *tee)
 50{
 51	struct ring_buf_manager *rb_mgr = &tee->rb_mgr;
 52
 53	if (!rb_mgr->ring_start)
 54		return;
 55
 56	free_pages((unsigned long)rb_mgr->ring_start,
 57		   get_order(rb_mgr->ring_size));
 58
 59	rb_mgr->ring_start = NULL;
 60	rb_mgr->ring_size = 0;
 61	rb_mgr->ring_pa = 0;
 62	mutex_destroy(&rb_mgr->mutex);
 63}
 64
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 65static
 66struct tee_init_ring_cmd *tee_alloc_cmd_buffer(struct psp_tee_device *tee)
 67{
 68	struct tee_init_ring_cmd *cmd;
 69
 70	cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
 71	if (!cmd)
 72		return NULL;
 73
 74	cmd->hi_addr = upper_32_bits(tee->rb_mgr.ring_pa);
 75	cmd->low_addr = lower_32_bits(tee->rb_mgr.ring_pa);
 76	cmd->size = tee->rb_mgr.ring_size;
 77
 78	dev_dbg(tee->dev, "tee: ring address: high = 0x%x low = 0x%x size = %u\n",
 79		cmd->hi_addr, cmd->low_addr, cmd->size);
 80
 81	return cmd;
 82}
 83
 84static inline void tee_free_cmd_buffer(struct tee_init_ring_cmd *cmd)
 85{
 86	kfree(cmd);
 87}
 88
 89static int tee_init_ring(struct psp_tee_device *tee)
 90{
 91	int ring_size = MAX_RING_BUFFER_ENTRIES * sizeof(struct tee_ring_cmd);
 92	struct tee_init_ring_cmd *cmd;
 
 93	unsigned int reg;
 94	int ret;
 95
 96	BUILD_BUG_ON(sizeof(struct tee_ring_cmd) != 1024);
 97
 98	ret = tee_alloc_ring(tee, ring_size);
 99	if (ret) {
100		dev_err(tee->dev, "tee: ring allocation failed %d\n", ret);
101		return ret;
102	}
103
104	tee->rb_mgr.wptr = 0;
105
106	cmd = tee_alloc_cmd_buffer(tee);
107	if (!cmd) {
108		tee_free_ring(tee);
109		return -ENOMEM;
110	}
111
 
 
112	/* Send command buffer details to Trusted OS by writing to
113	 * CPU-PSP message registers
114	 */
115	ret = psp_mailbox_command(tee->psp, PSP_CMD_TEE_RING_INIT, cmd,
116				  TEE_DEFAULT_CMD_TIMEOUT, &reg);
 
 
 
 
 
 
 
117	if (ret) {
118		dev_err(tee->dev, "tee: ring init command timed out, disabling TEE support\n");
119		tee_free_ring(tee);
120		psp_dead = true;
121		goto free_buf;
122	}
123
124	if (FIELD_GET(PSP_CMDRESP_STS, reg)) {
125		dev_err(tee->dev, "tee: ring init command failed (%#010lx)\n",
126			FIELD_GET(PSP_CMDRESP_STS, reg));
127		tee_free_ring(tee);
128		ret = -EIO;
129	}
130
131free_buf:
132	tee_free_cmd_buffer(cmd);
133
134	return ret;
135}
136
137static void tee_destroy_ring(struct psp_tee_device *tee)
138{
139	unsigned int reg;
140	int ret;
141
142	if (!tee->rb_mgr.ring_start)
143		return;
144
145	if (psp_dead)
146		goto free_ring;
147
148	ret = psp_mailbox_command(tee->psp, PSP_CMD_TEE_RING_DESTROY, NULL,
149				  TEE_DEFAULT_CMD_TIMEOUT, &reg);
 
 
150	if (ret) {
151		dev_err(tee->dev, "tee: ring destroy command timed out, disabling TEE support\n");
152		psp_dead = true;
153	} else if (FIELD_GET(PSP_CMDRESP_STS, reg)) {
154		dev_err(tee->dev, "tee: ring destroy command failed (%#010lx)\n",
155			FIELD_GET(PSP_CMDRESP_STS, reg));
156	}
157
158free_ring:
159	tee_free_ring(tee);
160}
161
162int tee_dev_init(struct psp_device *psp)
163{
164	struct device *dev = psp->dev;
165	struct psp_tee_device *tee;
166	int ret;
167
168	ret = -ENOMEM;
169	tee = devm_kzalloc(dev, sizeof(*tee), GFP_KERNEL);
170	if (!tee)
171		goto e_err;
172
173	psp->tee_data = tee;
174
175	tee->dev = dev;
176	tee->psp = psp;
177
178	tee->io_regs = psp->io_regs;
179
180	tee->vdata = (struct tee_vdata *)psp->vdata->tee;
181	if (!tee->vdata) {
182		ret = -ENODEV;
183		dev_err(dev, "tee: missing driver data\n");
184		goto e_err;
185	}
186
187	ret = tee_init_ring(tee);
188	if (ret) {
189		dev_err(dev, "tee: failed to init ring buffer\n");
190		goto e_err;
191	}
192
193	dev_notice(dev, "tee enabled\n");
194
195	return 0;
196
197e_err:
198	psp->tee_data = NULL;
199
200	dev_notice(dev, "tee initialization failed\n");
201
202	return ret;
203}
204
205void tee_dev_destroy(struct psp_device *psp)
206{
207	struct psp_tee_device *tee = psp->tee_data;
208
209	if (!tee)
210		return;
211
212	tee_destroy_ring(tee);
213}
214
215static int tee_submit_cmd(struct psp_tee_device *tee, enum tee_cmd_id cmd_id,
216			  void *buf, size_t len, struct tee_ring_cmd **resp)
217{
218	struct tee_ring_cmd *cmd;
219	int nloop = 1000, ret = 0;
220	u32 rptr;
221
222	*resp = NULL;
223
224	mutex_lock(&tee->rb_mgr.mutex);
225
226	/* Loop until empty entry found in ring buffer */
227	do {
228		/* Get pointer to ring buffer command entry */
229		cmd = (struct tee_ring_cmd *)
230			(tee->rb_mgr.ring_start + tee->rb_mgr.wptr);
231
232		rptr = ioread32(tee->io_regs + tee->vdata->ring_rptr_reg);
233
234		/* Check if ring buffer is full or command entry is waiting
235		 * for response from TEE
236		 */
237		if (!(tee->rb_mgr.wptr + sizeof(struct tee_ring_cmd) == rptr ||
238		      cmd->flag == CMD_WAITING_FOR_RESPONSE))
239			break;
240
241		dev_dbg(tee->dev, "tee: ring buffer full. rptr = %u wptr = %u\n",
242			rptr, tee->rb_mgr.wptr);
243
244		/* Wait if ring buffer is full or TEE is processing data */
245		mutex_unlock(&tee->rb_mgr.mutex);
246		schedule_timeout_interruptible(msecs_to_jiffies(10));
247		mutex_lock(&tee->rb_mgr.mutex);
248
249	} while (--nloop);
250
251	if (!nloop &&
252	    (tee->rb_mgr.wptr + sizeof(struct tee_ring_cmd) == rptr ||
253	     cmd->flag == CMD_WAITING_FOR_RESPONSE)) {
254		dev_err(tee->dev, "tee: ring buffer full. rptr = %u wptr = %u response flag %u\n",
255			rptr, tee->rb_mgr.wptr, cmd->flag);
256		ret = -EBUSY;
257		goto unlock;
258	}
259
260	/* Do not submit command if PSP got disabled while processing any
261	 * command in another thread
262	 */
263	if (psp_dead) {
264		ret = -EBUSY;
265		goto unlock;
266	}
267
268	/* Write command data into ring buffer */
269	cmd->cmd_id = cmd_id;
270	cmd->cmd_state = TEE_CMD_STATE_INIT;
271	memset(&cmd->buf[0], 0, sizeof(cmd->buf));
272	memcpy(&cmd->buf[0], buf, len);
273
274	/* Indicate driver is waiting for response */
275	cmd->flag = CMD_WAITING_FOR_RESPONSE;
276
277	/* Update local copy of write pointer */
278	tee->rb_mgr.wptr += sizeof(struct tee_ring_cmd);
279	if (tee->rb_mgr.wptr >= tee->rb_mgr.ring_size)
280		tee->rb_mgr.wptr = 0;
281
282	/* Trigger interrupt to Trusted OS */
283	iowrite32(tee->rb_mgr.wptr, tee->io_regs + tee->vdata->ring_wptr_reg);
284
285	/* The response is provided by Trusted OS in same
286	 * location as submitted data entry within ring buffer.
287	 */
288	*resp = cmd;
289
290unlock:
291	mutex_unlock(&tee->rb_mgr.mutex);
292
293	return ret;
294}
295
296static int tee_wait_cmd_completion(struct psp_tee_device *tee,
297				   struct tee_ring_cmd *resp,
298				   unsigned int timeout)
299{
300	/* ~1ms sleep per loop => nloop = timeout * 1000 */
301	int nloop = timeout * 1000;
302
303	while (--nloop) {
304		if (resp->cmd_state == TEE_CMD_STATE_COMPLETED)
305			return 0;
306
307		usleep_range(1000, 1100);
308	}
309
310	dev_err(tee->dev, "tee: command 0x%x timed out, disabling PSP\n",
311		resp->cmd_id);
312
313	psp_dead = true;
314
315	return -ETIMEDOUT;
316}
317
318int psp_tee_process_cmd(enum tee_cmd_id cmd_id, void *buf, size_t len,
319			u32 *status)
320{
321	struct psp_device *psp = psp_get_master_device();
322	struct psp_tee_device *tee;
323	struct tee_ring_cmd *resp;
324	int ret;
325
326	if (!buf || !status || !len || len > sizeof(resp->buf))
327		return -EINVAL;
328
329	*status = 0;
330
331	if (!psp || !psp->tee_data)
332		return -ENODEV;
333
334	if (psp_dead)
335		return -EBUSY;
336
337	tee = psp->tee_data;
338
339	ret = tee_submit_cmd(tee, cmd_id, buf, len, &resp);
340	if (ret)
341		return ret;
342
343	ret = tee_wait_cmd_completion(tee, resp, TEE_DEFAULT_RING_TIMEOUT);
344	if (ret) {
345		resp->flag = CMD_RESPONSE_TIMEDOUT;
346		return ret;
347	}
348
349	memcpy(buf, &resp->buf[0], len);
350	*status = resp->status;
351
352	resp->flag = CMD_RESPONSE_COPIED;
353
354	return 0;
355}
356EXPORT_SYMBOL(psp_tee_process_cmd);
357
358int psp_check_tee_status(void)
359{
360	struct psp_device *psp = psp_get_master_device();
361
362	if (!psp || !psp->tee_data)
363		return -ENODEV;
364
365	return 0;
366}
367EXPORT_SYMBOL(psp_check_tee_status);