xref: /openbmc/linux/drivers/bus/mhi/host/boot.c (revision fbb6b31a)
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 void 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 
32 	for (i = 0; i < img_info->entries - 1; i++, mhi_buf++, bhi_vec++) {
33 		bhi_vec->dma_addr = mhi_buf->dma_addr;
34 		bhi_vec->size = mhi_buf->len;
35 	}
36 
37 	dev_dbg(dev, "BHIe programming for RDDM\n");
38 
39 	mhi_write_reg(mhi_cntrl, base, BHIE_RXVECADDR_HIGH_OFFS,
40 		      upper_32_bits(mhi_buf->dma_addr));
41 
42 	mhi_write_reg(mhi_cntrl, base, BHIE_RXVECADDR_LOW_OFFS,
43 		      lower_32_bits(mhi_buf->dma_addr));
44 
45 	mhi_write_reg(mhi_cntrl, base, BHIE_RXVECSIZE_OFFS, mhi_buf->len);
46 	sequence_id = MHI_RANDOM_U32_NONZERO(BHIE_RXVECSTATUS_SEQNUM_BMSK);
47 
48 	mhi_write_reg_field(mhi_cntrl, base, BHIE_RXVECDB_OFFS,
49 			    BHIE_RXVECDB_SEQNUM_BMSK, sequence_id);
50 
51 	dev_dbg(dev, "Address: %p and len: 0x%zx sequence: %u\n",
52 		&mhi_buf->dma_addr, mhi_buf->len, sequence_id);
53 }
54 
55 /* Collect RDDM buffer during kernel panic */
56 static int __mhi_download_rddm_in_panic(struct mhi_controller *mhi_cntrl)
57 {
58 	int ret;
59 	u32 rx_status;
60 	enum mhi_ee_type ee;
61 	const u32 delayus = 2000;
62 	u32 retry = (mhi_cntrl->timeout_ms * 1000) / delayus;
63 	const u32 rddm_timeout_us = 200000;
64 	int rddm_retry = rddm_timeout_us / delayus;
65 	void __iomem *base = mhi_cntrl->bhie;
66 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
67 
68 	dev_dbg(dev, "Entered with pm_state:%s dev_state:%s ee:%s\n",
69 		to_mhi_pm_state_str(mhi_cntrl->pm_state),
70 		mhi_state_str(mhi_cntrl->dev_state),
71 		TO_MHI_EXEC_STR(mhi_cntrl->ee));
72 
73 	/*
74 	 * This should only be executing during a kernel panic, we expect all
75 	 * other cores to shutdown while we're collecting RDDM buffer. After
76 	 * returning from this function, we expect the device to reset.
77 	 *
78 	 * Normaly, we read/write pm_state only after grabbing the
79 	 * pm_lock, since we're in a panic, skipping it. Also there is no
80 	 * gurantee that this state change would take effect since
81 	 * we're setting it w/o grabbing pm_lock
82 	 */
83 	mhi_cntrl->pm_state = MHI_PM_LD_ERR_FATAL_DETECT;
84 	/* update should take the effect immediately */
85 	smp_wmb();
86 
87 	/*
88 	 * Make sure device is not already in RDDM. In case the device asserts
89 	 * and a kernel panic follows, device will already be in RDDM.
90 	 * Do not trigger SYS ERR again and proceed with waiting for
91 	 * image download completion.
92 	 */
93 	ee = mhi_get_exec_env(mhi_cntrl);
94 	if (ee == MHI_EE_MAX)
95 		goto error_exit_rddm;
96 
97 	if (ee != MHI_EE_RDDM) {
98 		dev_dbg(dev, "Trigger device into RDDM mode using SYS ERR\n");
99 		mhi_set_mhi_state(mhi_cntrl, MHI_STATE_SYS_ERR);
100 
101 		dev_dbg(dev, "Waiting for device to enter RDDM\n");
102 		while (rddm_retry--) {
103 			ee = mhi_get_exec_env(mhi_cntrl);
104 			if (ee == MHI_EE_RDDM)
105 				break;
106 
107 			udelay(delayus);
108 		}
109 
110 		if (rddm_retry <= 0) {
111 			/* Hardware reset so force device to enter RDDM */
112 			dev_dbg(dev,
113 				"Did not enter RDDM, do a host req reset\n");
114 			mhi_write_reg(mhi_cntrl, mhi_cntrl->regs,
115 				      MHI_SOC_RESET_REQ_OFFSET,
116 				      MHI_SOC_RESET_REQ);
117 			udelay(delayus);
118 		}
119 
120 		ee = mhi_get_exec_env(mhi_cntrl);
121 	}
122 
123 	dev_dbg(dev,
124 		"Waiting for RDDM image download via BHIe, current EE:%s\n",
125 		TO_MHI_EXEC_STR(ee));
126 
127 	while (retry--) {
128 		ret = mhi_read_reg_field(mhi_cntrl, base, BHIE_RXVECSTATUS_OFFS,
129 					 BHIE_RXVECSTATUS_STATUS_BMSK, &rx_status);
130 		if (ret)
131 			return -EIO;
132 
133 		if (rx_status == BHIE_RXVECSTATUS_STATUS_XFER_COMPL)
134 			return 0;
135 
136 		udelay(delayus);
137 	}
138 
139 	ee = mhi_get_exec_env(mhi_cntrl);
140 	ret = mhi_read_reg(mhi_cntrl, base, BHIE_RXVECSTATUS_OFFS, &rx_status);
141 
142 	dev_err(dev, "RXVEC_STATUS: 0x%x\n", rx_status);
143 
144 error_exit_rddm:
145 	dev_err(dev, "RDDM transfer failed. Current EE: %s\n",
146 		TO_MHI_EXEC_STR(ee));
147 
148 	return -EIO;
149 }
150 
151 /* Download RDDM image from device */
152 int mhi_download_rddm_image(struct mhi_controller *mhi_cntrl, bool in_panic)
153 {
154 	void __iomem *base = mhi_cntrl->bhie;
155 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
156 	u32 rx_status;
157 
158 	if (in_panic)
159 		return __mhi_download_rddm_in_panic(mhi_cntrl);
160 
161 	dev_dbg(dev, "Waiting for RDDM image download via BHIe\n");
162 
163 	/* Wait for the image download to complete */
164 	wait_event_timeout(mhi_cntrl->state_event,
165 			   mhi_read_reg_field(mhi_cntrl, base,
166 					      BHIE_RXVECSTATUS_OFFS,
167 					      BHIE_RXVECSTATUS_STATUS_BMSK,
168 					      &rx_status) || rx_status,
169 			   msecs_to_jiffies(mhi_cntrl->timeout_ms));
170 
171 	return (rx_status == BHIE_RXVECSTATUS_STATUS_XFER_COMPL) ? 0 : -EIO;
172 }
173 EXPORT_SYMBOL_GPL(mhi_download_rddm_image);
174 
175 static int mhi_fw_load_bhie(struct mhi_controller *mhi_cntrl,
176 			    const struct mhi_buf *mhi_buf)
177 {
178 	void __iomem *base = mhi_cntrl->bhie;
179 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
180 	rwlock_t *pm_lock = &mhi_cntrl->pm_lock;
181 	u32 tx_status, sequence_id;
182 	int ret;
183 
184 	read_lock_bh(pm_lock);
185 	if (!MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state)) {
186 		read_unlock_bh(pm_lock);
187 		return -EIO;
188 	}
189 
190 	sequence_id = MHI_RANDOM_U32_NONZERO(BHIE_TXVECSTATUS_SEQNUM_BMSK);
191 	dev_dbg(dev, "Starting image download via BHIe. Sequence ID: %u\n",
192 		sequence_id);
193 	mhi_write_reg(mhi_cntrl, base, BHIE_TXVECADDR_HIGH_OFFS,
194 		      upper_32_bits(mhi_buf->dma_addr));
195 
196 	mhi_write_reg(mhi_cntrl, base, BHIE_TXVECADDR_LOW_OFFS,
197 		      lower_32_bits(mhi_buf->dma_addr));
198 
199 	mhi_write_reg(mhi_cntrl, base, BHIE_TXVECSIZE_OFFS, mhi_buf->len);
200 
201 	mhi_write_reg_field(mhi_cntrl, base, BHIE_TXVECDB_OFFS,
202 			    BHIE_TXVECDB_SEQNUM_BMSK, sequence_id);
203 	read_unlock_bh(pm_lock);
204 
205 	/* Wait for the image download to complete */
206 	ret = wait_event_timeout(mhi_cntrl->state_event,
207 				 MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state) ||
208 				 mhi_read_reg_field(mhi_cntrl, base,
209 						   BHIE_TXVECSTATUS_OFFS,
210 						   BHIE_TXVECSTATUS_STATUS_BMSK,
211 						   &tx_status) || tx_status,
212 				 msecs_to_jiffies(mhi_cntrl->timeout_ms));
213 	if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state) ||
214 	    tx_status != BHIE_TXVECSTATUS_STATUS_XFER_COMPL)
215 		return -EIO;
216 
217 	return (!ret) ? -ETIMEDOUT : 0;
218 }
219 
220 static int mhi_fw_load_bhi(struct mhi_controller *mhi_cntrl,
221 			   dma_addr_t dma_addr,
222 			   size_t size)
223 {
224 	u32 tx_status, val, session_id;
225 	int i, ret;
226 	void __iomem *base = mhi_cntrl->bhi;
227 	rwlock_t *pm_lock = &mhi_cntrl->pm_lock;
228 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
229 	struct {
230 		char *name;
231 		u32 offset;
232 	} error_reg[] = {
233 		{ "ERROR_CODE", BHI_ERRCODE },
234 		{ "ERROR_DBG1", BHI_ERRDBG1 },
235 		{ "ERROR_DBG2", BHI_ERRDBG2 },
236 		{ "ERROR_DBG3", BHI_ERRDBG3 },
237 		{ NULL },
238 	};
239 
240 	read_lock_bh(pm_lock);
241 	if (!MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state)) {
242 		read_unlock_bh(pm_lock);
243 		goto invalid_pm_state;
244 	}
245 
246 	session_id = MHI_RANDOM_U32_NONZERO(BHI_TXDB_SEQNUM_BMSK);
247 	dev_dbg(dev, "Starting image download via BHI. Session ID: %u\n",
248 		session_id);
249 	mhi_write_reg(mhi_cntrl, base, BHI_STATUS, 0);
250 	mhi_write_reg(mhi_cntrl, base, BHI_IMGADDR_HIGH,
251 		      upper_32_bits(dma_addr));
252 	mhi_write_reg(mhi_cntrl, base, BHI_IMGADDR_LOW,
253 		      lower_32_bits(dma_addr));
254 	mhi_write_reg(mhi_cntrl, base, BHI_IMGSIZE, size);
255 	mhi_write_reg(mhi_cntrl, base, BHI_IMGTXDB, session_id);
256 	read_unlock_bh(pm_lock);
257 
258 	/* Wait for the image download to complete */
259 	ret = wait_event_timeout(mhi_cntrl->state_event,
260 			   MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state) ||
261 			   mhi_read_reg_field(mhi_cntrl, base, BHI_STATUS,
262 					      BHI_STATUS_MASK, &tx_status) || tx_status,
263 			   msecs_to_jiffies(mhi_cntrl->timeout_ms));
264 	if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state))
265 		goto invalid_pm_state;
266 
267 	if (tx_status == BHI_STATUS_ERROR) {
268 		dev_err(dev, "Image transfer failed\n");
269 		read_lock_bh(pm_lock);
270 		if (MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state)) {
271 			for (i = 0; error_reg[i].name; i++) {
272 				ret = mhi_read_reg(mhi_cntrl, base,
273 						   error_reg[i].offset, &val);
274 				if (ret)
275 					break;
276 				dev_err(dev, "Reg: %s value: 0x%x\n",
277 					error_reg[i].name, val);
278 			}
279 		}
280 		read_unlock_bh(pm_lock);
281 		goto invalid_pm_state;
282 	}
283 
284 	return (!ret) ? -ETIMEDOUT : 0;
285 
286 invalid_pm_state:
287 
288 	return -EIO;
289 }
290 
291 void mhi_free_bhie_table(struct mhi_controller *mhi_cntrl,
292 			 struct image_info *image_info)
293 {
294 	int i;
295 	struct mhi_buf *mhi_buf = image_info->mhi_buf;
296 
297 	for (i = 0; i < image_info->entries; i++, mhi_buf++)
298 		dma_free_coherent(mhi_cntrl->cntrl_dev, mhi_buf->len,
299 				  mhi_buf->buf, mhi_buf->dma_addr);
300 
301 	kfree(image_info->mhi_buf);
302 	kfree(image_info);
303 }
304 
305 int mhi_alloc_bhie_table(struct mhi_controller *mhi_cntrl,
306 			 struct image_info **image_info,
307 			 size_t alloc_size)
308 {
309 	size_t seg_size = mhi_cntrl->seg_len;
310 	int segments = DIV_ROUND_UP(alloc_size, seg_size) + 1;
311 	int i;
312 	struct image_info *img_info;
313 	struct mhi_buf *mhi_buf;
314 
315 	img_info = kzalloc(sizeof(*img_info), GFP_KERNEL);
316 	if (!img_info)
317 		return -ENOMEM;
318 
319 	/* Allocate memory for entries */
320 	img_info->mhi_buf = kcalloc(segments, sizeof(*img_info->mhi_buf),
321 				    GFP_KERNEL);
322 	if (!img_info->mhi_buf)
323 		goto error_alloc_mhi_buf;
324 
325 	/* Allocate and populate vector table */
326 	mhi_buf = img_info->mhi_buf;
327 	for (i = 0; i < segments; i++, mhi_buf++) {
328 		size_t vec_size = seg_size;
329 
330 		/* Vector table is the last entry */
331 		if (i == segments - 1)
332 			vec_size = sizeof(struct bhi_vec_entry) * i;
333 
334 		mhi_buf->len = vec_size;
335 		mhi_buf->buf = dma_alloc_coherent(mhi_cntrl->cntrl_dev,
336 						  vec_size, &mhi_buf->dma_addr,
337 						  GFP_KERNEL);
338 		if (!mhi_buf->buf)
339 			goto error_alloc_segment;
340 	}
341 
342 	img_info->bhi_vec = img_info->mhi_buf[segments - 1].buf;
343 	img_info->entries = segments;
344 	*image_info = img_info;
345 
346 	return 0;
347 
348 error_alloc_segment:
349 	for (--i, --mhi_buf; i >= 0; i--, mhi_buf--)
350 		dma_free_coherent(mhi_cntrl->cntrl_dev, mhi_buf->len,
351 				  mhi_buf->buf, mhi_buf->dma_addr);
352 
353 error_alloc_mhi_buf:
354 	kfree(img_info);
355 
356 	return -ENOMEM;
357 }
358 
359 static void mhi_firmware_copy(struct mhi_controller *mhi_cntrl,
360 			      const struct firmware *firmware,
361 			      struct image_info *img_info)
362 {
363 	size_t remainder = firmware->size;
364 	size_t to_cpy;
365 	const u8 *buf = firmware->data;
366 	struct mhi_buf *mhi_buf = img_info->mhi_buf;
367 	struct bhi_vec_entry *bhi_vec = img_info->bhi_vec;
368 
369 	while (remainder) {
370 		to_cpy = min(remainder, mhi_buf->len);
371 		memcpy(mhi_buf->buf, buf, to_cpy);
372 		bhi_vec->dma_addr = mhi_buf->dma_addr;
373 		bhi_vec->size = to_cpy;
374 
375 		buf += to_cpy;
376 		remainder -= to_cpy;
377 		bhi_vec++;
378 		mhi_buf++;
379 	}
380 }
381 
382 void mhi_fw_load_handler(struct mhi_controller *mhi_cntrl)
383 {
384 	const struct firmware *firmware = NULL;
385 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
386 	const char *fw_name;
387 	void *buf;
388 	dma_addr_t dma_addr;
389 	size_t size;
390 	int i, ret;
391 
392 	if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
393 		dev_err(dev, "Device MHI is not in valid state\n");
394 		return;
395 	}
396 
397 	/* save hardware info from BHI */
398 	ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_SERIALNU,
399 			   &mhi_cntrl->serial_number);
400 	if (ret)
401 		dev_err(dev, "Could not capture serial number via BHI\n");
402 
403 	for (i = 0; i < ARRAY_SIZE(mhi_cntrl->oem_pk_hash); i++) {
404 		ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_OEMPKHASH(i),
405 				   &mhi_cntrl->oem_pk_hash[i]);
406 		if (ret) {
407 			dev_err(dev, "Could not capture OEM PK HASH via BHI\n");
408 			break;
409 		}
410 	}
411 
412 	/* wait for ready on pass through or any other execution environment */
413 	if (!MHI_FW_LOAD_CAPABLE(mhi_cntrl->ee))
414 		goto fw_load_ready_state;
415 
416 	fw_name = (mhi_cntrl->ee == MHI_EE_EDL) ?
417 		mhi_cntrl->edl_image : mhi_cntrl->fw_image;
418 
419 	if (!fw_name || (mhi_cntrl->fbc_download && (!mhi_cntrl->sbl_size ||
420 						     !mhi_cntrl->seg_len))) {
421 		dev_err(dev,
422 			"No firmware image defined or !sbl_size || !seg_len\n");
423 		goto error_fw_load;
424 	}
425 
426 	ret = request_firmware(&firmware, fw_name, dev);
427 	if (ret) {
428 		dev_err(dev, "Error loading firmware: %d\n", ret);
429 		goto error_fw_load;
430 	}
431 
432 	size = (mhi_cntrl->fbc_download) ? mhi_cntrl->sbl_size : firmware->size;
433 
434 	/* SBL size provided is maximum size, not necessarily the image size */
435 	if (size > firmware->size)
436 		size = firmware->size;
437 
438 	buf = dma_alloc_coherent(mhi_cntrl->cntrl_dev, size, &dma_addr,
439 				 GFP_KERNEL);
440 	if (!buf) {
441 		release_firmware(firmware);
442 		goto error_fw_load;
443 	}
444 
445 	/* Download image using BHI */
446 	memcpy(buf, firmware->data, size);
447 	ret = mhi_fw_load_bhi(mhi_cntrl, dma_addr, size);
448 	dma_free_coherent(mhi_cntrl->cntrl_dev, size, buf, dma_addr);
449 
450 	/* Error or in EDL mode, we're done */
451 	if (ret) {
452 		dev_err(dev, "MHI did not load image over BHI, ret: %d\n", ret);
453 		release_firmware(firmware);
454 		goto error_fw_load;
455 	}
456 
457 	/* Wait for ready since EDL image was loaded */
458 	if (fw_name == mhi_cntrl->edl_image) {
459 		release_firmware(firmware);
460 		goto fw_load_ready_state;
461 	}
462 
463 	write_lock_irq(&mhi_cntrl->pm_lock);
464 	mhi_cntrl->dev_state = MHI_STATE_RESET;
465 	write_unlock_irq(&mhi_cntrl->pm_lock);
466 
467 	/*
468 	 * If we're doing fbc, populate vector tables while
469 	 * device transitioning into MHI READY state
470 	 */
471 	if (mhi_cntrl->fbc_download) {
472 		ret = mhi_alloc_bhie_table(mhi_cntrl, &mhi_cntrl->fbc_image,
473 					   firmware->size);
474 		if (ret) {
475 			release_firmware(firmware);
476 			goto error_fw_load;
477 		}
478 
479 		/* Load the firmware into BHIE vec table */
480 		mhi_firmware_copy(mhi_cntrl, firmware, mhi_cntrl->fbc_image);
481 	}
482 
483 	release_firmware(firmware);
484 
485 fw_load_ready_state:
486 	/* Transitioning into MHI RESET->READY state */
487 	ret = mhi_ready_state_transition(mhi_cntrl);
488 	if (ret) {
489 		dev_err(dev, "MHI did not enter READY state\n");
490 		goto error_ready_state;
491 	}
492 
493 	dev_info(dev, "Wait for device to enter SBL or Mission mode\n");
494 	return;
495 
496 error_ready_state:
497 	if (mhi_cntrl->fbc_download) {
498 		mhi_free_bhie_table(mhi_cntrl, mhi_cntrl->fbc_image);
499 		mhi_cntrl->fbc_image = NULL;
500 	}
501 
502 error_fw_load:
503 	mhi_cntrl->pm_state = MHI_PM_FW_DL_ERR;
504 	wake_up_all(&mhi_cntrl->state_event);
505 }
506 
507 int mhi_download_amss_image(struct mhi_controller *mhi_cntrl)
508 {
509 	struct image_info *image_info = mhi_cntrl->fbc_image;
510 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
511 	int ret;
512 
513 	if (!image_info)
514 		return -EIO;
515 
516 	ret = mhi_fw_load_bhie(mhi_cntrl,
517 			       /* Vector table is the last entry */
518 			       &image_info->mhi_buf[image_info->entries - 1]);
519 	if (ret) {
520 		dev_err(dev, "MHI did not load AMSS, ret:%d\n", ret);
521 		mhi_cntrl->pm_state = MHI_PM_FW_DL_ERR;
522 		wake_up_all(&mhi_cntrl->state_event);
523 	}
524 
525 	return ret;
526 }
527