xref: /linux/drivers/usb/host/xhci-pci-renesas.c (revision 02680c23d7b3febe45ea3d4f9818c2b2dc89020a)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (C) 2019-2020 Linaro Limited */
3 
4 #include <linux/acpi.h>
5 #include <linux/firmware.h>
6 #include <linux/module.h>
7 #include <linux/pci.h>
8 #include <linux/slab.h>
9 #include <asm/unaligned.h>
10 
11 #include "xhci.h"
12 #include "xhci-trace.h"
13 #include "xhci-pci.h"
14 
15 #define RENESAS_FW_VERSION				0x6C
16 #define RENESAS_ROM_CONFIG				0xF0
17 #define RENESAS_FW_STATUS				0xF4
18 #define RENESAS_FW_STATUS_MSB				0xF5
19 #define RENESAS_ROM_STATUS				0xF6
20 #define RENESAS_ROM_STATUS_MSB				0xF7
21 #define RENESAS_DATA0					0xF8
22 #define RENESAS_DATA1					0xFC
23 
24 #define RENESAS_FW_VERSION_FIELD			GENMASK(23, 7)
25 #define RENESAS_FW_VERSION_OFFSET			8
26 
27 #define RENESAS_FW_STATUS_DOWNLOAD_ENABLE		BIT(0)
28 #define RENESAS_FW_STATUS_LOCK				BIT(1)
29 #define RENESAS_FW_STATUS_RESULT			GENMASK(6, 4)
30   #define RENESAS_FW_STATUS_INVALID			0
31   #define RENESAS_FW_STATUS_SUCCESS			BIT(4)
32   #define RENESAS_FW_STATUS_ERROR			BIT(5)
33 #define RENESAS_FW_STATUS_SET_DATA0			BIT(8)
34 #define RENESAS_FW_STATUS_SET_DATA1			BIT(9)
35 
36 #define RENESAS_ROM_STATUS_ACCESS			BIT(0)
37 #define RENESAS_ROM_STATUS_ERASE			BIT(1)
38 #define RENESAS_ROM_STATUS_RELOAD			BIT(2)
39 #define RENESAS_ROM_STATUS_RESULT			GENMASK(6, 4)
40   #define RENESAS_ROM_STATUS_NO_RESULT			0
41   #define RENESAS_ROM_STATUS_SUCCESS			BIT(4)
42   #define RENESAS_ROM_STATUS_ERROR			BIT(5)
43 #define RENESAS_ROM_STATUS_SET_DATA0			BIT(8)
44 #define RENESAS_ROM_STATUS_SET_DATA1			BIT(9)
45 #define RENESAS_ROM_STATUS_ROM_EXISTS			BIT(15)
46 
47 #define RENESAS_ROM_ERASE_MAGIC				0x5A65726F
48 #define RENESAS_ROM_WRITE_MAGIC				0x53524F4D
49 
50 #define RENESAS_RETRY	10000
51 #define RENESAS_DELAY	10
52 
53 static int renesas_fw_download_image(struct pci_dev *dev,
54 				     const u32 *fw, size_t step, bool rom)
55 {
56 	size_t i;
57 	int err;
58 	u8 fw_status;
59 	bool data0_or_data1;
60 	u32 status_reg;
61 
62 	if (rom)
63 		status_reg = RENESAS_ROM_STATUS_MSB;
64 	else
65 		status_reg = RENESAS_FW_STATUS_MSB;
66 
67 	/*
68 	 * The hardware does alternate between two 32-bit pages.
69 	 * (This is because each row of the firmware is 8 bytes).
70 	 *
71 	 * for even steps we use DATA0, for odd steps DATA1.
72 	 */
73 	data0_or_data1 = (step & 1) == 1;
74 
75 	/* step+1. Read "Set DATAX" and confirm it is cleared. */
76 	for (i = 0; i < RENESAS_RETRY; i++) {
77 		err = pci_read_config_byte(dev, status_reg, &fw_status);
78 		if (err) {
79 			dev_err(&dev->dev, "Read Status failed: %d\n",
80 				pcibios_err_to_errno(err));
81 			return pcibios_err_to_errno(err);
82 		}
83 		if (!(fw_status & BIT(data0_or_data1)))
84 			break;
85 
86 		udelay(RENESAS_DELAY);
87 	}
88 	if (i == RENESAS_RETRY) {
89 		dev_err(&dev->dev, "Timeout for Set DATAX step: %zd\n", step);
90 		return -ETIMEDOUT;
91 	}
92 
93 	/*
94 	 * step+2. Write FW data to "DATAX".
95 	 * "LSB is left" => force little endian
96 	 */
97 	err = pci_write_config_dword(dev, data0_or_data1 ?
98 				     RENESAS_DATA1 : RENESAS_DATA0,
99 				     (__force u32)cpu_to_le32(fw[step]));
100 	if (err) {
101 		dev_err(&dev->dev, "Write to DATAX failed: %d\n",
102 			pcibios_err_to_errno(err));
103 		return pcibios_err_to_errno(err);
104 	}
105 
106 	udelay(100);
107 
108 	/* step+3. Set "Set DATAX". */
109 	err = pci_write_config_byte(dev, status_reg, BIT(data0_or_data1));
110 	if (err) {
111 		dev_err(&dev->dev, "Write config for DATAX failed: %d\n",
112 			pcibios_err_to_errno(err));
113 		return pcibios_err_to_errno(err);
114 	}
115 
116 	return 0;
117 }
118 
119 static int renesas_fw_verify(const void *fw_data,
120 			     size_t length)
121 {
122 	u16 fw_version_pointer;
123 	u16 fw_version;
124 
125 	/*
126 	 * The Firmware's Data Format is describe in
127 	 * "6.3 Data Format" R19UH0078EJ0500 Rev.5.00 page 124
128 	 */
129 
130 	/*
131 	 * The bootrom chips of the big brother have sizes up to 64k, let's
132 	 * assume that's the biggest the firmware can get.
133 	 */
134 	if (length < 0x1000 || length >= 0x10000) {
135 		pr_err("firmware is size %zd is not (4k - 64k).",
136 			length);
137 		return -EINVAL;
138 	}
139 
140 	/* The First 2 bytes are fixed value (55aa). "LSB on Left" */
141 	if (get_unaligned_le16(fw_data) != 0x55aa) {
142 		pr_err("no valid firmware header found.");
143 		return -EINVAL;
144 	}
145 
146 	/* verify the firmware version position and print it. */
147 	fw_version_pointer = get_unaligned_le16(fw_data + 4);
148 	if (fw_version_pointer + 2 >= length) {
149 		pr_err("fw ver pointer is outside of the firmware image");
150 		return -EINVAL;
151 	}
152 
153 	fw_version = get_unaligned_le16(fw_data + fw_version_pointer);
154 	pr_err("got firmware version: %02x.", fw_version);
155 
156 	return 0;
157 }
158 
159 static bool renesas_check_rom(struct pci_dev *pdev)
160 {
161 	u16 rom_status;
162 	int retval;
163 
164 	/* Check if external ROM exists */
165 	retval = pci_read_config_word(pdev, RENESAS_ROM_STATUS, &rom_status);
166 	if (retval)
167 		return false;
168 
169 	rom_status &= RENESAS_ROM_STATUS_ROM_EXISTS;
170 	if (rom_status) {
171 		dev_dbg(&pdev->dev, "External ROM exists\n");
172 		return true; /* External ROM exists */
173 	}
174 
175 	return false;
176 }
177 
178 static int renesas_check_rom_state(struct pci_dev *pdev)
179 {
180 	u16 rom_state;
181 	u32 version;
182 	int err;
183 
184 	/* check FW version */
185 	err = pci_read_config_dword(pdev, RENESAS_FW_VERSION, &version);
186 	if (err)
187 		return pcibios_err_to_errno(err);
188 
189 	version &= RENESAS_FW_VERSION_FIELD;
190 	version = version >> RENESAS_FW_VERSION_OFFSET;
191 	dev_dbg(&pdev->dev, "Found ROM version: %x\n", version);
192 
193 	/*
194 	 * Test if ROM is present and loaded, if so we can skip everything
195 	 */
196 	err = pci_read_config_word(pdev, RENESAS_ROM_STATUS, &rom_state);
197 	if (err)
198 		return pcibios_err_to_errno(err);
199 
200 	if (rom_state & BIT(15)) {
201 		/* ROM exists */
202 		dev_dbg(&pdev->dev, "ROM exists\n");
203 
204 		/* Check the "Result Code" Bits (6:4) and act accordingly */
205 		switch (rom_state & RENESAS_ROM_STATUS_RESULT) {
206 		case RENESAS_ROM_STATUS_SUCCESS:
207 			return 0;
208 
209 		case RENESAS_ROM_STATUS_NO_RESULT: /* No result yet */
210 			return 0;
211 
212 		case RENESAS_ROM_STATUS_ERROR: /* Error State */
213 		default: /* All other states are marked as "Reserved states" */
214 			dev_err(&pdev->dev, "Invalid ROM..");
215 			break;
216 		}
217 	}
218 
219 	return -EIO;
220 }
221 
222 static int renesas_fw_check_running(struct pci_dev *pdev)
223 {
224 	u8 fw_state;
225 	int err;
226 
227 	/* Check if device has ROM and loaded, if so skip everything */
228 	err = renesas_check_rom(pdev);
229 	if (err) { /* we have rom */
230 		err = renesas_check_rom_state(pdev);
231 		if (!err)
232 			return err;
233 	}
234 
235 	/*
236 	 * Test if the device is actually needing the firmware. As most
237 	 * BIOSes will initialize the device for us. If the device is
238 	 * initialized.
239 	 */
240 	err = pci_read_config_byte(pdev, RENESAS_FW_STATUS, &fw_state);
241 	if (err)
242 		return pcibios_err_to_errno(err);
243 
244 	/*
245 	 * Check if "FW Download Lock" is locked. If it is and the FW is
246 	 * ready we can simply continue. If the FW is not ready, we have
247 	 * to give up.
248 	 */
249 	if (fw_state & RENESAS_FW_STATUS_LOCK) {
250 		dev_dbg(&pdev->dev, "FW Download Lock is engaged.");
251 
252 		if (fw_state & RENESAS_FW_STATUS_SUCCESS)
253 			return 0;
254 
255 		dev_err(&pdev->dev,
256 			"FW Download Lock is set and FW is not ready. Giving Up.");
257 		return -EIO;
258 	}
259 
260 	/*
261 	 * Check if "FW Download Enable" is set. If someone (us?) tampered
262 	 * with it and it can't be reset, we have to give up too... and
263 	 * ask for a forgiveness and a reboot.
264 	 */
265 	if (fw_state & RENESAS_FW_STATUS_DOWNLOAD_ENABLE) {
266 		dev_err(&pdev->dev,
267 			"FW Download Enable is stale. Giving Up (poweroff/reboot needed).");
268 		return -EIO;
269 	}
270 
271 	/* Otherwise, Check the "Result Code" Bits (6:4) and act accordingly */
272 	switch (fw_state & RENESAS_FW_STATUS_RESULT) {
273 	case 0: /* No result yet */
274 		dev_dbg(&pdev->dev, "FW is not ready/loaded yet.");
275 
276 		/* tell the caller, that this device needs the firmware. */
277 		return 1;
278 
279 	case RENESAS_FW_STATUS_SUCCESS: /* Success, device should be working. */
280 		dev_dbg(&pdev->dev, "FW is ready.");
281 		return 0;
282 
283 	case RENESAS_FW_STATUS_ERROR: /* Error State */
284 		dev_err(&pdev->dev,
285 			"hardware is in an error state. Giving up (poweroff/reboot needed).");
286 		return -ENODEV;
287 
288 	default: /* All other states are marked as "Reserved states" */
289 		dev_err(&pdev->dev,
290 			"hardware is in an invalid state %lx. Giving up (poweroff/reboot needed).",
291 			(fw_state & RENESAS_FW_STATUS_RESULT) >> 4);
292 		return -EINVAL;
293 	}
294 }
295 
296 static int renesas_fw_download(struct pci_dev *pdev,
297 			       const struct firmware *fw)
298 {
299 	const u32 *fw_data = (const u32 *)fw->data;
300 	size_t i;
301 	int err;
302 	u8 fw_status;
303 
304 	/*
305 	 * For more information and the big picture: please look at the
306 	 * "Firmware Download Sequence" in "7.1 FW Download Interface"
307 	 * of R19UH0078EJ0500 Rev.5.00 page 131
308 	 */
309 
310 	/*
311 	 * 0. Set "FW Download Enable" bit in the
312 	 * "FW Download Control & Status Register" at 0xF4
313 	 */
314 	err = pci_write_config_byte(pdev, RENESAS_FW_STATUS,
315 				    RENESAS_FW_STATUS_DOWNLOAD_ENABLE);
316 	if (err)
317 		return pcibios_err_to_errno(err);
318 
319 	/* 1 - 10 follow one step after the other. */
320 	for (i = 0; i < fw->size / 4; i++) {
321 		err = renesas_fw_download_image(pdev, fw_data, i, false);
322 		if (err) {
323 			dev_err(&pdev->dev,
324 				"Firmware Download Step %zd failed at position %zd bytes with (%d).",
325 				i, i * 4, err);
326 			return err;
327 		}
328 	}
329 
330 	/*
331 	 * This sequence continues until the last data is written to
332 	 * "DATA0" or "DATA1". Naturally, we wait until "SET DATA0/1"
333 	 * is cleared by the hardware beforehand.
334 	 */
335 	for (i = 0; i < RENESAS_RETRY; i++) {
336 		err = pci_read_config_byte(pdev, RENESAS_FW_STATUS_MSB,
337 					   &fw_status);
338 		if (err)
339 			return pcibios_err_to_errno(err);
340 		if (!(fw_status & (BIT(0) | BIT(1))))
341 			break;
342 
343 		udelay(RENESAS_DELAY);
344 	}
345 	if (i == RENESAS_RETRY)
346 		dev_warn(&pdev->dev, "Final Firmware Download step timed out.");
347 
348 	/*
349 	 * 11. After finishing writing the last data of FW, the
350 	 * System Software must clear "FW Download Enable"
351 	 */
352 	err = pci_write_config_byte(pdev, RENESAS_FW_STATUS, 0);
353 	if (err)
354 		return pcibios_err_to_errno(err);
355 
356 	/* 12. Read "Result Code" and confirm it is good. */
357 	for (i = 0; i < RENESAS_RETRY; i++) {
358 		err = pci_read_config_byte(pdev, RENESAS_FW_STATUS, &fw_status);
359 		if (err)
360 			return pcibios_err_to_errno(err);
361 		if (fw_status & RENESAS_FW_STATUS_SUCCESS)
362 			break;
363 
364 		udelay(RENESAS_DELAY);
365 	}
366 	if (i == RENESAS_RETRY) {
367 		/* Timed out / Error - let's see if we can fix this */
368 		err = renesas_fw_check_running(pdev);
369 		switch (err) {
370 		case 0: /*
371 			 * we shouldn't end up here.
372 			 * maybe it took a little bit longer.
373 			 * But all should be well?
374 			 */
375 			break;
376 
377 		case 1: /* (No result yet! */
378 			dev_err(&pdev->dev, "FW Load timedout");
379 			return -ETIMEDOUT;
380 
381 		default:
382 			return err;
383 		}
384 	}
385 
386 	return 0;
387 }
388 
389 static void renesas_rom_erase(struct pci_dev *pdev)
390 {
391 	int retval, i;
392 	u8 status;
393 
394 	dev_dbg(&pdev->dev, "Performing ROM Erase...\n");
395 	retval = pci_write_config_dword(pdev, RENESAS_DATA0,
396 					RENESAS_ROM_ERASE_MAGIC);
397 	if (retval) {
398 		dev_err(&pdev->dev, "ROM erase, magic word write failed: %d\n",
399 			pcibios_err_to_errno(retval));
400 		return;
401 	}
402 
403 	retval = pci_read_config_byte(pdev, RENESAS_ROM_STATUS, &status);
404 	if (retval) {
405 		dev_err(&pdev->dev, "ROM status read failed: %d\n",
406 			pcibios_err_to_errno(retval));
407 		return;
408 	}
409 	status |= RENESAS_ROM_STATUS_ERASE;
410 	retval = pci_write_config_byte(pdev, RENESAS_ROM_STATUS, status);
411 	if (retval) {
412 		dev_err(&pdev->dev, "ROM erase set word write failed\n");
413 		return;
414 	}
415 
416 	/* sleep a bit while ROM is erased */
417 	msleep(20);
418 
419 	for (i = 0; i < RENESAS_RETRY; i++) {
420 		retval = pci_read_config_byte(pdev, RENESAS_ROM_STATUS,
421 					      &status);
422 		status &= RENESAS_ROM_STATUS_ERASE;
423 		if (!status)
424 			break;
425 
426 		mdelay(RENESAS_DELAY);
427 	}
428 
429 	if (i == RENESAS_RETRY)
430 		dev_dbg(&pdev->dev, "Chip erase timedout: %x\n", status);
431 
432 	dev_dbg(&pdev->dev, "ROM Erase... Done success\n");
433 }
434 
435 static bool renesas_setup_rom(struct pci_dev *pdev, const struct firmware *fw)
436 {
437 	const u32 *fw_data = (const u32 *)fw->data;
438 	int err, i;
439 	u8 status;
440 
441 	/* 2. Write magic word to Data0 */
442 	err = pci_write_config_dword(pdev, RENESAS_DATA0,
443 				     RENESAS_ROM_WRITE_MAGIC);
444 	if (err)
445 		return false;
446 
447 	/* 3. Set External ROM access */
448 	err = pci_write_config_byte(pdev, RENESAS_ROM_STATUS,
449 				    RENESAS_ROM_STATUS_ACCESS);
450 	if (err)
451 		goto remove_bypass;
452 
453 	/* 4. Check the result */
454 	err = pci_read_config_byte(pdev, RENESAS_ROM_STATUS, &status);
455 	if (err)
456 		goto remove_bypass;
457 	status &= GENMASK(6, 4);
458 	if (status) {
459 		dev_err(&pdev->dev,
460 			"setting external rom failed: %x\n", status);
461 		goto remove_bypass;
462 	}
463 
464 	/* 5 to 16 Write FW to DATA0/1 while checking SetData0/1 */
465 	for (i = 0; i < fw->size / 4; i++) {
466 		err = renesas_fw_download_image(pdev, fw_data, i, true);
467 		if (err) {
468 			dev_err(&pdev->dev,
469 				"ROM Download Step %d failed at position %d bytes with (%d)\n",
470 				 i, i * 4, err);
471 			goto remove_bypass;
472 		}
473 	}
474 
475 	/*
476 	 * wait till DATA0/1 is cleared
477 	 */
478 	for (i = 0; i < RENESAS_RETRY; i++) {
479 		err = pci_read_config_byte(pdev, RENESAS_ROM_STATUS_MSB,
480 					   &status);
481 		if (err)
482 			goto remove_bypass;
483 		if (!(status & (BIT(0) | BIT(1))))
484 			break;
485 
486 		udelay(RENESAS_DELAY);
487 	}
488 	if (i == RENESAS_RETRY) {
489 		dev_err(&pdev->dev, "Final Firmware ROM Download step timed out\n");
490 		goto remove_bypass;
491 	}
492 
493 	/* 17. Remove bypass */
494 	err = pci_write_config_byte(pdev, RENESAS_ROM_STATUS, 0);
495 	if (err)
496 		return false;
497 
498 	udelay(10);
499 
500 	/* 18. check result */
501 	for (i = 0; i < RENESAS_RETRY; i++) {
502 		err = pci_read_config_byte(pdev, RENESAS_ROM_STATUS, &status);
503 		if (err) {
504 			dev_err(&pdev->dev, "Read ROM status failed:%d\n",
505 				pcibios_err_to_errno(err));
506 			return false;
507 		}
508 		status &= RENESAS_ROM_STATUS_RESULT;
509 		if (status ==  RENESAS_ROM_STATUS_SUCCESS) {
510 			dev_dbg(&pdev->dev, "Download ROM success\n");
511 			break;
512 		}
513 		udelay(RENESAS_DELAY);
514 	}
515 	if (i == RENESAS_RETRY) { /* Timed out */
516 		dev_err(&pdev->dev,
517 			"Download to external ROM TO: %x\n", status);
518 		return false;
519 	}
520 
521 	dev_dbg(&pdev->dev, "Download to external ROM succeeded\n");
522 
523 	/* Last step set Reload */
524 	err = pci_write_config_byte(pdev, RENESAS_ROM_STATUS,
525 				    RENESAS_ROM_STATUS_RELOAD);
526 	if (err) {
527 		dev_err(&pdev->dev, "Set ROM execute failed: %d\n",
528 			pcibios_err_to_errno(err));
529 		return false;
530 	}
531 
532 	/*
533 	 * wait till Reload is cleared
534 	 */
535 	for (i = 0; i < RENESAS_RETRY; i++) {
536 		err = pci_read_config_byte(pdev, RENESAS_ROM_STATUS, &status);
537 		if (err)
538 			return false;
539 		if (!(status & RENESAS_ROM_STATUS_RELOAD))
540 			break;
541 
542 		udelay(RENESAS_DELAY);
543 	}
544 	if (i == RENESAS_RETRY) {
545 		dev_err(&pdev->dev, "ROM Exec timed out: %x\n", status);
546 		return false;
547 	}
548 
549 	return true;
550 
551 remove_bypass:
552 	pci_write_config_byte(pdev, RENESAS_ROM_STATUS, 0);
553 	return false;
554 }
555 
556 static int renesas_load_fw(struct pci_dev *pdev, const struct firmware *fw)
557 {
558 	int err = 0;
559 	bool rom;
560 
561 	/* Check if the device has external ROM */
562 	rom = renesas_check_rom(pdev);
563 	if (rom) {
564 		/* perform chip erase first */
565 		renesas_rom_erase(pdev);
566 
567 		/* lets try loading fw on ROM first */
568 		rom = renesas_setup_rom(pdev, fw);
569 		if (!rom) {
570 			dev_dbg(&pdev->dev,
571 				"ROM load failed, falling back on FW load\n");
572 		} else {
573 			dev_dbg(&pdev->dev,
574 				"ROM load success\n");
575 			goto exit;
576 		}
577 	}
578 
579 	err = renesas_fw_download(pdev, fw);
580 
581 exit:
582 	if (err)
583 		dev_err(&pdev->dev, "firmware failed to download (%d).", err);
584 	return err;
585 }
586 
587 int renesas_xhci_check_request_fw(struct pci_dev *pdev,
588 				  const struct pci_device_id *id)
589 {
590 	struct xhci_driver_data *driver_data =
591 			(struct xhci_driver_data *)id->driver_data;
592 	const char *fw_name = driver_data->firmware;
593 	const struct firmware *fw;
594 	int err;
595 
596 	err = renesas_fw_check_running(pdev);
597 	/* Continue ahead, if the firmware is already running. */
598 	if (err == 0)
599 		return 0;
600 
601 	if (err != 1)
602 		return err;
603 
604 	pci_dev_get(pdev);
605 	err = request_firmware(&fw, fw_name, &pdev->dev);
606 	pci_dev_put(pdev);
607 	if (err) {
608 		dev_err(&pdev->dev, "request_firmware failed: %d\n", err);
609 		return err;
610 	}
611 
612 	err = renesas_fw_verify(fw->data, fw->size);
613 	if (err)
614 		goto exit;
615 
616 	err = renesas_load_fw(pdev, fw);
617 exit:
618 	release_firmware(fw);
619 	return err;
620 }
621 EXPORT_SYMBOL_GPL(renesas_xhci_check_request_fw);
622 
623 void renesas_xhci_pci_exit(struct pci_dev *dev)
624 {
625 }
626 EXPORT_SYMBOL_GPL(renesas_xhci_pci_exit);
627 
628 MODULE_LICENSE("GPL v2");
629