xref: /openbmc/linux/drivers/bus/mhi/host/boot.c (revision 6db6b729)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
4  *
5  */
6 
7 #include <linux/delay.h>
8 #include <linux/device.h>
9 #include <linux/dma-direction.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/firmware.h>
12 #include <linux/interrupt.h>
13 #include <linux/list.h>
14 #include <linux/mhi.h>
15 #include <linux/module.h>
16 #include <linux/random.h>
17 #include <linux/slab.h>
18 #include <linux/wait.h>
19 #include "internal.h"
20 
21 /* Setup RDDM vector table for RDDM transfer and program RXVEC */
22 int mhi_rddm_prepare(struct mhi_controller *mhi_cntrl,
23 		     struct image_info *img_info)
24 {
25 	struct mhi_buf *mhi_buf = img_info->mhi_buf;
26 	struct bhi_vec_entry *bhi_vec = img_info->bhi_vec;
27 	void __iomem *base = mhi_cntrl->bhie;
28 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
29 	u32 sequence_id;
30 	unsigned int i;
31 	int ret;
32 
33 	for (i = 0; i < img_info->entries - 1; i++, mhi_buf++, bhi_vec++) {
34 		bhi_vec->dma_addr = mhi_buf->dma_addr;
35 		bhi_vec->size = mhi_buf->len;
36 	}
37 
38 	dev_dbg(dev, "BHIe programming for RDDM\n");
39 
40 	mhi_write_reg(mhi_cntrl, base, BHIE_RXVECADDR_HIGH_OFFS,
41 		      upper_32_bits(mhi_buf->dma_addr));
42 
43 	mhi_write_reg(mhi_cntrl, base, BHIE_RXVECADDR_LOW_OFFS,
44 		      lower_32_bits(mhi_buf->dma_addr));
45 
46 	mhi_write_reg(mhi_cntrl, base, BHIE_RXVECSIZE_OFFS, mhi_buf->len);
47 	sequence_id = MHI_RANDOM_U32_NONZERO(BHIE_RXVECSTATUS_SEQNUM_BMSK);
48 
49 	ret = mhi_write_reg_field(mhi_cntrl, base, BHIE_RXVECDB_OFFS,
50 				  BHIE_RXVECDB_SEQNUM_BMSK, sequence_id);
51 	if (ret) {
52 		dev_err(dev, "Failed to write sequence ID for BHIE_RXVECDB\n");
53 		return ret;
54 	}
55 
56 	dev_dbg(dev, "Address: %p and len: 0x%zx sequence: %u\n",
57 		&mhi_buf->dma_addr, mhi_buf->len, sequence_id);
58 
59 	return 0;
60 }
61 
62 /* Collect RDDM buffer during kernel panic */
63 static int __mhi_download_rddm_in_panic(struct mhi_controller *mhi_cntrl)
64 {
65 	int ret;
66 	u32 rx_status;
67 	enum mhi_ee_type ee;
68 	const u32 delayus = 2000;
69 	u32 retry = (mhi_cntrl->timeout_ms * 1000) / delayus;
70 	const u32 rddm_timeout_us = 200000;
71 	int rddm_retry = rddm_timeout_us / delayus;
72 	void __iomem *base = mhi_cntrl->bhie;
73 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
74 
75 	dev_dbg(dev, "Entered with pm_state:%s dev_state:%s ee:%s\n",
76 		to_mhi_pm_state_str(mhi_cntrl->pm_state),
77 		mhi_state_str(mhi_cntrl->dev_state),
78 		TO_MHI_EXEC_STR(mhi_cntrl->ee));
79 
80 	/*
81 	 * This should only be executing during a kernel panic, we expect all
82 	 * other cores to shutdown while we're collecting RDDM buffer. After
83 	 * returning from this function, we expect the device to reset.
84 	 *
85 	 * Normaly, we read/write pm_state only after grabbing the
86 	 * pm_lock, since we're in a panic, skipping it. Also there is no
87 	 * gurantee that this state change would take effect since
88 	 * we're setting it w/o grabbing pm_lock
89 	 */
90 	mhi_cntrl->pm_state = MHI_PM_LD_ERR_FATAL_DETECT;
91 	/* update should take the effect immediately */
92 	smp_wmb();
93 
94 	/*
95 	 * Make sure device is not already in RDDM. In case the device asserts
96 	 * and a kernel panic follows, device will already be in RDDM.
97 	 * Do not trigger SYS ERR again and proceed with waiting for
98 	 * image download completion.
99 	 */
100 	ee = mhi_get_exec_env(mhi_cntrl);
101 	if (ee == MHI_EE_MAX)
102 		goto error_exit_rddm;
103 
104 	if (ee != MHI_EE_RDDM) {
105 		dev_dbg(dev, "Trigger device into RDDM mode using SYS ERR\n");
106 		mhi_set_mhi_state(mhi_cntrl, MHI_STATE_SYS_ERR);
107 
108 		dev_dbg(dev, "Waiting for device to enter RDDM\n");
109 		while (rddm_retry--) {
110 			ee = mhi_get_exec_env(mhi_cntrl);
111 			if (ee == MHI_EE_RDDM)
112 				break;
113 
114 			udelay(delayus);
115 		}
116 
117 		if (rddm_retry <= 0) {
118 			/* Hardware reset so force device to enter RDDM */
119 			dev_dbg(dev,
120 				"Did not enter RDDM, do a host req reset\n");
121 			mhi_soc_reset(mhi_cntrl);
122 			udelay(delayus);
123 		}
124 
125 		ee = mhi_get_exec_env(mhi_cntrl);
126 	}
127 
128 	dev_dbg(dev,
129 		"Waiting for RDDM image download via BHIe, current EE:%s\n",
130 		TO_MHI_EXEC_STR(ee));
131 
132 	while (retry--) {
133 		ret = mhi_read_reg_field(mhi_cntrl, base, BHIE_RXVECSTATUS_OFFS,
134 					 BHIE_RXVECSTATUS_STATUS_BMSK, &rx_status);
135 		if (ret)
136 			return -EIO;
137 
138 		if (rx_status == BHIE_RXVECSTATUS_STATUS_XFER_COMPL)
139 			return 0;
140 
141 		udelay(delayus);
142 	}
143 
144 	ee = mhi_get_exec_env(mhi_cntrl);
145 	ret = mhi_read_reg(mhi_cntrl, base, BHIE_RXVECSTATUS_OFFS, &rx_status);
146 
147 	dev_err(dev, "RXVEC_STATUS: 0x%x\n", rx_status);
148 
149 error_exit_rddm:
150 	dev_err(dev, "RDDM transfer failed. Current EE: %s\n",
151 		TO_MHI_EXEC_STR(ee));
152 
153 	return -EIO;
154 }
155 
156 /* Download RDDM image from device */
157 int mhi_download_rddm_image(struct mhi_controller *mhi_cntrl, bool in_panic)
158 {
159 	void __iomem *base = mhi_cntrl->bhie;
160 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
161 	u32 rx_status;
162 
163 	if (in_panic)
164 		return __mhi_download_rddm_in_panic(mhi_cntrl);
165 
166 	dev_dbg(dev, "Waiting for RDDM image download via BHIe\n");
167 
168 	/* Wait for the image download to complete */
169 	wait_event_timeout(mhi_cntrl->state_event,
170 			   mhi_read_reg_field(mhi_cntrl, base,
171 					      BHIE_RXVECSTATUS_OFFS,
172 					      BHIE_RXVECSTATUS_STATUS_BMSK,
173 					      &rx_status) || rx_status,
174 			   msecs_to_jiffies(mhi_cntrl->timeout_ms));
175 
176 	return (rx_status == BHIE_RXVECSTATUS_STATUS_XFER_COMPL) ? 0 : -EIO;
177 }
178 EXPORT_SYMBOL_GPL(mhi_download_rddm_image);
179 
180 static int mhi_fw_load_bhie(struct mhi_controller *mhi_cntrl,
181 			    const struct mhi_buf *mhi_buf)
182 {
183 	void __iomem *base = mhi_cntrl->bhie;
184 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
185 	rwlock_t *pm_lock = &mhi_cntrl->pm_lock;
186 	u32 tx_status, sequence_id;
187 	int ret;
188 
189 	read_lock_bh(pm_lock);
190 	if (!MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state)) {
191 		read_unlock_bh(pm_lock);
192 		return -EIO;
193 	}
194 
195 	sequence_id = MHI_RANDOM_U32_NONZERO(BHIE_TXVECSTATUS_SEQNUM_BMSK);
196 	dev_dbg(dev, "Starting image download via BHIe. Sequence ID: %u\n",
197 		sequence_id);
198 	mhi_write_reg(mhi_cntrl, base, BHIE_TXVECADDR_HIGH_OFFS,
199 		      upper_32_bits(mhi_buf->dma_addr));
200 
201 	mhi_write_reg(mhi_cntrl, base, BHIE_TXVECADDR_LOW_OFFS,
202 		      lower_32_bits(mhi_buf->dma_addr));
203 
204 	mhi_write_reg(mhi_cntrl, base, BHIE_TXVECSIZE_OFFS, mhi_buf->len);
205 
206 	ret = mhi_write_reg_field(mhi_cntrl, base, BHIE_TXVECDB_OFFS,
207 				  BHIE_TXVECDB_SEQNUM_BMSK, sequence_id);
208 	read_unlock_bh(pm_lock);
209 
210 	if (ret)
211 		return ret;
212 
213 	/* Wait for the image download to complete */
214 	ret = wait_event_timeout(mhi_cntrl->state_event,
215 				 MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state) ||
216 				 mhi_read_reg_field(mhi_cntrl, base,
217 						   BHIE_TXVECSTATUS_OFFS,
218 						   BHIE_TXVECSTATUS_STATUS_BMSK,
219 						   &tx_status) || tx_status,
220 				 msecs_to_jiffies(mhi_cntrl->timeout_ms));
221 	if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state) ||
222 	    tx_status != BHIE_TXVECSTATUS_STATUS_XFER_COMPL)
223 		return -EIO;
224 
225 	return (!ret) ? -ETIMEDOUT : 0;
226 }
227 
228 static int mhi_fw_load_bhi(struct mhi_controller *mhi_cntrl,
229 			   dma_addr_t dma_addr,
230 			   size_t size)
231 {
232 	u32 tx_status, val, session_id;
233 	int i, ret;
234 	void __iomem *base = mhi_cntrl->bhi;
235 	rwlock_t *pm_lock = &mhi_cntrl->pm_lock;
236 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
237 	struct {
238 		char *name;
239 		u32 offset;
240 	} error_reg[] = {
241 		{ "ERROR_CODE", BHI_ERRCODE },
242 		{ "ERROR_DBG1", BHI_ERRDBG1 },
243 		{ "ERROR_DBG2", BHI_ERRDBG2 },
244 		{ "ERROR_DBG3", BHI_ERRDBG3 },
245 		{ NULL },
246 	};
247 
248 	read_lock_bh(pm_lock);
249 	if (!MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state)) {
250 		read_unlock_bh(pm_lock);
251 		goto invalid_pm_state;
252 	}
253 
254 	session_id = MHI_RANDOM_U32_NONZERO(BHI_TXDB_SEQNUM_BMSK);
255 	dev_dbg(dev, "Starting image download via BHI. Session ID: %u\n",
256 		session_id);
257 	mhi_write_reg(mhi_cntrl, base, BHI_STATUS, 0);
258 	mhi_write_reg(mhi_cntrl, base, BHI_IMGADDR_HIGH,
259 		      upper_32_bits(dma_addr));
260 	mhi_write_reg(mhi_cntrl, base, BHI_IMGADDR_LOW,
261 		      lower_32_bits(dma_addr));
262 	mhi_write_reg(mhi_cntrl, base, BHI_IMGSIZE, size);
263 	mhi_write_reg(mhi_cntrl, base, BHI_IMGTXDB, session_id);
264 	read_unlock_bh(pm_lock);
265 
266 	/* Wait for the image download to complete */
267 	ret = wait_event_timeout(mhi_cntrl->state_event,
268 			   MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state) ||
269 			   mhi_read_reg_field(mhi_cntrl, base, BHI_STATUS,
270 					      BHI_STATUS_MASK, &tx_status) || tx_status,
271 			   msecs_to_jiffies(mhi_cntrl->timeout_ms));
272 	if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state))
273 		goto invalid_pm_state;
274 
275 	if (tx_status == BHI_STATUS_ERROR) {
276 		dev_err(dev, "Image transfer failed\n");
277 		read_lock_bh(pm_lock);
278 		if (MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state)) {
279 			for (i = 0; error_reg[i].name; i++) {
280 				ret = mhi_read_reg(mhi_cntrl, base,
281 						   error_reg[i].offset, &val);
282 				if (ret)
283 					break;
284 				dev_err(dev, "Reg: %s value: 0x%x\n",
285 					error_reg[i].name, val);
286 			}
287 		}
288 		read_unlock_bh(pm_lock);
289 		goto invalid_pm_state;
290 	}
291 
292 	return (!ret) ? -ETIMEDOUT : 0;
293 
294 invalid_pm_state:
295 
296 	return -EIO;
297 }
298 
299 void mhi_free_bhie_table(struct mhi_controller *mhi_cntrl,
300 			 struct image_info *image_info)
301 {
302 	int i;
303 	struct mhi_buf *mhi_buf = image_info->mhi_buf;
304 
305 	for (i = 0; i < image_info->entries; i++, mhi_buf++)
306 		dma_free_coherent(mhi_cntrl->cntrl_dev, mhi_buf->len,
307 				  mhi_buf->buf, mhi_buf->dma_addr);
308 
309 	kfree(image_info->mhi_buf);
310 	kfree(image_info);
311 }
312 
313 int mhi_alloc_bhie_table(struct mhi_controller *mhi_cntrl,
314 			 struct image_info **image_info,
315 			 size_t alloc_size)
316 {
317 	size_t seg_size = mhi_cntrl->seg_len;
318 	int segments = DIV_ROUND_UP(alloc_size, seg_size) + 1;
319 	int i;
320 	struct image_info *img_info;
321 	struct mhi_buf *mhi_buf;
322 
323 	img_info = kzalloc(sizeof(*img_info), GFP_KERNEL);
324 	if (!img_info)
325 		return -ENOMEM;
326 
327 	/* Allocate memory for entries */
328 	img_info->mhi_buf = kcalloc(segments, sizeof(*img_info->mhi_buf),
329 				    GFP_KERNEL);
330 	if (!img_info->mhi_buf)
331 		goto error_alloc_mhi_buf;
332 
333 	/* Allocate and populate vector table */
334 	mhi_buf = img_info->mhi_buf;
335 	for (i = 0; i < segments; i++, mhi_buf++) {
336 		size_t vec_size = seg_size;
337 
338 		/* Vector table is the last entry */
339 		if (i == segments - 1)
340 			vec_size = sizeof(struct bhi_vec_entry) * i;
341 
342 		mhi_buf->len = vec_size;
343 		mhi_buf->buf = dma_alloc_coherent(mhi_cntrl->cntrl_dev,
344 						  vec_size, &mhi_buf->dma_addr,
345 						  GFP_KERNEL);
346 		if (!mhi_buf->buf)
347 			goto error_alloc_segment;
348 	}
349 
350 	img_info->bhi_vec = img_info->mhi_buf[segments - 1].buf;
351 	img_info->entries = segments;
352 	*image_info = img_info;
353 
354 	return 0;
355 
356 error_alloc_segment:
357 	for (--i, --mhi_buf; i >= 0; i--, mhi_buf--)
358 		dma_free_coherent(mhi_cntrl->cntrl_dev, mhi_buf->len,
359 				  mhi_buf->buf, mhi_buf->dma_addr);
360 
361 error_alloc_mhi_buf:
362 	kfree(img_info);
363 
364 	return -ENOMEM;
365 }
366 
367 static void mhi_firmware_copy(struct mhi_controller *mhi_cntrl,
368 			      const u8 *buf, size_t remainder,
369 			      struct image_info *img_info)
370 {
371 	size_t to_cpy;
372 	struct mhi_buf *mhi_buf = img_info->mhi_buf;
373 	struct bhi_vec_entry *bhi_vec = img_info->bhi_vec;
374 
375 	while (remainder) {
376 		to_cpy = min(remainder, mhi_buf->len);
377 		memcpy(mhi_buf->buf, buf, to_cpy);
378 		bhi_vec->dma_addr = mhi_buf->dma_addr;
379 		bhi_vec->size = to_cpy;
380 
381 		buf += to_cpy;
382 		remainder -= to_cpy;
383 		bhi_vec++;
384 		mhi_buf++;
385 	}
386 }
387 
388 void mhi_fw_load_handler(struct mhi_controller *mhi_cntrl)
389 {
390 	const struct firmware *firmware = NULL;
391 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
392 	enum mhi_pm_state new_state;
393 	const char *fw_name;
394 	const u8 *fw_data;
395 	void *buf;
396 	dma_addr_t dma_addr;
397 	size_t size, fw_sz;
398 	int i, ret;
399 
400 	if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
401 		dev_err(dev, "Device MHI is not in valid state\n");
402 		return;
403 	}
404 
405 	/* save hardware info from BHI */
406 	ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_SERIALNU,
407 			   &mhi_cntrl->serial_number);
408 	if (ret)
409 		dev_err(dev, "Could not capture serial number via BHI\n");
410 
411 	for (i = 0; i < ARRAY_SIZE(mhi_cntrl->oem_pk_hash); i++) {
412 		ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_OEMPKHASH(i),
413 				   &mhi_cntrl->oem_pk_hash[i]);
414 		if (ret) {
415 			dev_err(dev, "Could not capture OEM PK HASH via BHI\n");
416 			break;
417 		}
418 	}
419 
420 	/* wait for ready on pass through or any other execution environment */
421 	if (!MHI_FW_LOAD_CAPABLE(mhi_cntrl->ee))
422 		goto fw_load_ready_state;
423 
424 	fw_name = (mhi_cntrl->ee == MHI_EE_EDL) ?
425 		mhi_cntrl->edl_image : mhi_cntrl->fw_image;
426 
427 	/* check if the driver has already provided the firmware data */
428 	if (!fw_name && mhi_cntrl->fbc_download &&
429 	    mhi_cntrl->fw_data && mhi_cntrl->fw_sz) {
430 		if (!mhi_cntrl->sbl_size) {
431 			dev_err(dev, "fw_data provided but no sbl_size\n");
432 			goto error_fw_load;
433 		}
434 
435 		size = mhi_cntrl->sbl_size;
436 		fw_data = mhi_cntrl->fw_data;
437 		fw_sz = mhi_cntrl->fw_sz;
438 		goto skip_req_fw;
439 	}
440 
441 	if (!fw_name || (mhi_cntrl->fbc_download && (!mhi_cntrl->sbl_size ||
442 						     !mhi_cntrl->seg_len))) {
443 		dev_err(dev,
444 			"No firmware image defined or !sbl_size || !seg_len\n");
445 		goto error_fw_load;
446 	}
447 
448 	ret = request_firmware(&firmware, fw_name, dev);
449 	if (ret) {
450 		dev_err(dev, "Error loading firmware: %d\n", ret);
451 		goto error_fw_load;
452 	}
453 
454 	size = (mhi_cntrl->fbc_download) ? mhi_cntrl->sbl_size : firmware->size;
455 
456 	/* SBL size provided is maximum size, not necessarily the image size */
457 	if (size > firmware->size)
458 		size = firmware->size;
459 
460 	fw_data = firmware->data;
461 	fw_sz = firmware->size;
462 
463 skip_req_fw:
464 	buf = dma_alloc_coherent(mhi_cntrl->cntrl_dev, size, &dma_addr,
465 				 GFP_KERNEL);
466 	if (!buf) {
467 		release_firmware(firmware);
468 		goto error_fw_load;
469 	}
470 
471 	/* Download image using BHI */
472 	memcpy(buf, fw_data, size);
473 	ret = mhi_fw_load_bhi(mhi_cntrl, dma_addr, size);
474 	dma_free_coherent(mhi_cntrl->cntrl_dev, size, buf, dma_addr);
475 
476 	/* Error or in EDL mode, we're done */
477 	if (ret) {
478 		dev_err(dev, "MHI did not load image over BHI, ret: %d\n", ret);
479 		release_firmware(firmware);
480 		goto error_fw_load;
481 	}
482 
483 	/* Wait for ready since EDL image was loaded */
484 	if (fw_name && fw_name == mhi_cntrl->edl_image) {
485 		release_firmware(firmware);
486 		goto fw_load_ready_state;
487 	}
488 
489 	write_lock_irq(&mhi_cntrl->pm_lock);
490 	mhi_cntrl->dev_state = MHI_STATE_RESET;
491 	write_unlock_irq(&mhi_cntrl->pm_lock);
492 
493 	/*
494 	 * If we're doing fbc, populate vector tables while
495 	 * device transitioning into MHI READY state
496 	 */
497 	if (mhi_cntrl->fbc_download) {
498 		ret = mhi_alloc_bhie_table(mhi_cntrl, &mhi_cntrl->fbc_image, fw_sz);
499 		if (ret) {
500 			release_firmware(firmware);
501 			goto error_fw_load;
502 		}
503 
504 		/* Load the firmware into BHIE vec table */
505 		mhi_firmware_copy(mhi_cntrl, fw_data, fw_sz, mhi_cntrl->fbc_image);
506 	}
507 
508 	release_firmware(firmware);
509 
510 fw_load_ready_state:
511 	/* Transitioning into MHI RESET->READY state */
512 	ret = mhi_ready_state_transition(mhi_cntrl);
513 	if (ret) {
514 		dev_err(dev, "MHI did not enter READY state\n");
515 		goto error_ready_state;
516 	}
517 
518 	dev_info(dev, "Wait for device to enter SBL or Mission mode\n");
519 	return;
520 
521 error_ready_state:
522 	if (mhi_cntrl->fbc_download) {
523 		mhi_free_bhie_table(mhi_cntrl, mhi_cntrl->fbc_image);
524 		mhi_cntrl->fbc_image = NULL;
525 	}
526 
527 error_fw_load:
528 	write_lock_irq(&mhi_cntrl->pm_lock);
529 	new_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_FW_DL_ERR);
530 	write_unlock_irq(&mhi_cntrl->pm_lock);
531 	if (new_state == MHI_PM_FW_DL_ERR)
532 		wake_up_all(&mhi_cntrl->state_event);
533 }
534 
535 int mhi_download_amss_image(struct mhi_controller *mhi_cntrl)
536 {
537 	struct image_info *image_info = mhi_cntrl->fbc_image;
538 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
539 	enum mhi_pm_state new_state;
540 	int ret;
541 
542 	if (!image_info)
543 		return -EIO;
544 
545 	ret = mhi_fw_load_bhie(mhi_cntrl,
546 			       /* Vector table is the last entry */
547 			       &image_info->mhi_buf[image_info->entries - 1]);
548 	if (ret) {
549 		dev_err(dev, "MHI did not load AMSS, ret:%d\n", ret);
550 		write_lock_irq(&mhi_cntrl->pm_lock);
551 		new_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_FW_DL_ERR);
552 		write_unlock_irq(&mhi_cntrl->pm_lock);
553 		if (new_state == MHI_PM_FW_DL_ERR)
554 			wake_up_all(&mhi_cntrl->state_event);
555 	}
556 
557 	return ret;
558 }
559