xref: /linux/drivers/firmware/microchip/mpfs-auto-update.c (revision 55d0969c451159cff86949b38c39171cab962069)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Microchip Polarfire SoC "Auto Update" FPGA reprogramming.
4  *
5  * Documentation of this functionality is available in the "PolarFire® FPGA and
6  * PolarFire SoC FPGA Programming" User Guide.
7  *
8  * Copyright (c) 2022-2023 Microchip Corporation. All rights reserved.
9  *
10  * Author: Conor Dooley <conor.dooley@microchip.com>
11  */
12 #include <linux/cleanup.h>
13 #include <linux/debugfs.h>
14 #include <linux/firmware.h>
15 #include <linux/math.h>
16 #include <linux/module.h>
17 #include <linux/mtd/mtd.h>
18 #include <linux/platform_device.h>
19 #include <linux/sizes.h>
20 
21 #include <soc/microchip/mpfs.h>
22 
23 #define AUTO_UPDATE_DEFAULT_MBOX_OFFSET		0u
24 #define AUTO_UPDATE_DEFAULT_RESP_OFFSET		0u
25 
26 #define AUTO_UPDATE_FEATURE_CMD_OPCODE		0x05u
27 #define AUTO_UPDATE_FEATURE_CMD_DATA_SIZE	0u
28 #define AUTO_UPDATE_FEATURE_RESP_SIZE		33u
29 #define AUTO_UPDATE_FEATURE_CMD_DATA		NULL
30 #define AUTO_UPDATE_FEATURE_ENABLED		BIT(5)
31 
32 #define AUTO_UPDATE_AUTHENTICATE_CMD_OPCODE	0x22u
33 #define AUTO_UPDATE_AUTHENTICATE_CMD_DATA_SIZE	0u
34 #define AUTO_UPDATE_AUTHENTICATE_RESP_SIZE	1u
35 #define AUTO_UPDATE_AUTHENTICATE_CMD_DATA	NULL
36 
37 #define AUTO_UPDATE_PROGRAM_CMD_OPCODE		0x46u
38 #define AUTO_UPDATE_PROGRAM_CMD_DATA_SIZE	0u
39 #define AUTO_UPDATE_PROGRAM_RESP_SIZE		1u
40 #define AUTO_UPDATE_PROGRAM_CMD_DATA		NULL
41 
42 /*
43  * SPI Flash layout example:
44  * |------------------------------| 0x0000000
45  * | 1 KiB                        |
46  * | SPI "directories"            |
47  * |------------------------------| 0x0000400
48  * | 1 MiB                        |
49  * | Reserved area                |
50  * | Used for bitstream info      |
51  * |------------------------------| 0x0100400
52  * | 20 MiB                       |
53  * | Golden Image                 |
54  * |------------------------------| 0x1500400
55  * | 20 MiB                       |
56  * | Auto Upgrade Image           |
57  * |------------------------------| 0x2900400
58  * | 20 MiB                       |
59  * | Reserved for multi-image IAP |
60  * | Unused for Auto Upgrade      |
61  * |------------------------------| 0x3D00400
62  * | ? B                          |
63  * | Unused                       |
64  * |------------------------------| 0x?
65  */
66 #define AUTO_UPDATE_DIRECTORY_BASE	0u
67 #define AUTO_UPDATE_DIRECTORY_WIDTH	4u
68 #define AUTO_UPDATE_GOLDEN_INDEX	0u
69 #define AUTO_UPDATE_UPGRADE_INDEX	1u
70 #define AUTO_UPDATE_BLANK_INDEX		2u
71 #define AUTO_UPDATE_GOLDEN_DIRECTORY	(AUTO_UPDATE_DIRECTORY_WIDTH * AUTO_UPDATE_GOLDEN_INDEX)
72 #define AUTO_UPDATE_UPGRADE_DIRECTORY	(AUTO_UPDATE_DIRECTORY_WIDTH * AUTO_UPDATE_UPGRADE_INDEX)
73 #define AUTO_UPDATE_BLANK_DIRECTORY	(AUTO_UPDATE_DIRECTORY_WIDTH * AUTO_UPDATE_BLANK_INDEX)
74 #define AUTO_UPDATE_DIRECTORY_SIZE	SZ_1K
75 #define AUTO_UPDATE_INFO_BASE		AUTO_UPDATE_DIRECTORY_SIZE
76 #define AUTO_UPDATE_INFO_SIZE		SZ_1M
77 #define AUTO_UPDATE_BITSTREAM_BASE	(AUTO_UPDATE_DIRECTORY_SIZE + AUTO_UPDATE_INFO_SIZE)
78 
79 #define AUTO_UPDATE_TIMEOUT_MS		60000
80 
81 struct mpfs_auto_update_priv {
82 	struct mpfs_sys_controller *sys_controller;
83 	struct device *dev;
84 	struct mtd_info *flash;
85 	struct fw_upload *fw_uploader;
86 	struct completion programming_complete;
87 	size_t size_per_bitstream;
88 	bool cancel_request;
89 };
90 
91 static bool mpfs_auto_update_is_bitstream_info(const u8 *data, u32 size)
92 {
93 	if (size < 4)
94 		return false;
95 
96 	if (data[0] == 0x4d && data[1] == 0x43 && data[2] == 0x48 && data[3] == 0x50)
97 		return true;
98 
99 	return false;
100 }
101 
102 static enum fw_upload_err mpfs_auto_update_prepare(struct fw_upload *fw_uploader, const u8 *data,
103 						   u32 size)
104 {
105 	struct mpfs_auto_update_priv *priv = fw_uploader->dd_handle;
106 	size_t erase_size = AUTO_UPDATE_DIRECTORY_SIZE;
107 
108 	/*
109 	 * Verifying the Golden Image is idealistic. It will be evaluated
110 	 * against the currently programmed image and thus may fail - due to
111 	 * either rollback protection (if its an older version than that in use)
112 	 * or if the version is the same as that of the in-use image.
113 	 * Extracting the information as to why a failure occurred is not
114 	 * currently possible due to limitations of the system controller
115 	 * driver. If those are fixed, verification of the Golden Image should
116 	 * be added here.
117 	 */
118 
119 	priv->flash = mpfs_sys_controller_get_flash(priv->sys_controller);
120 	if (!priv->flash)
121 		return FW_UPLOAD_ERR_HW_ERROR;
122 
123 	erase_size = round_up(erase_size, (u64)priv->flash->erasesize);
124 
125 	/*
126 	 * We need to calculate if we have enough space in the flash for the
127 	 * new image.
128 	 * First, chop off the first 1 KiB as it's reserved for the directory.
129 	 * The 1 MiB reserved for design info needs to be ignored also.
130 	 * All that remains is carved into 3 & rounded down to the erasesize.
131 	 * If this is smaller than the image size, we abort.
132 	 * There's also no need to consume more than 20 MiB per image.
133 	 */
134 	priv->size_per_bitstream = priv->flash->size - SZ_1K - SZ_1M;
135 	priv->size_per_bitstream = round_down(priv->size_per_bitstream / 3, erase_size);
136 	if (priv->size_per_bitstream > 20 * SZ_1M)
137 		priv->size_per_bitstream = 20 * SZ_1M;
138 
139 	if (priv->size_per_bitstream < size) {
140 		dev_err(priv->dev,
141 			"flash device has insufficient capacity to store this bitstream\n");
142 		return FW_UPLOAD_ERR_INVALID_SIZE;
143 	}
144 
145 	priv->cancel_request = false;
146 
147 	return FW_UPLOAD_ERR_NONE;
148 }
149 
150 static void mpfs_auto_update_cancel(struct fw_upload *fw_uploader)
151 {
152 	struct mpfs_auto_update_priv *priv = fw_uploader->dd_handle;
153 
154 	priv->cancel_request = true;
155 }
156 
157 static enum fw_upload_err mpfs_auto_update_poll_complete(struct fw_upload *fw_uploader)
158 {
159 	struct mpfs_auto_update_priv *priv = fw_uploader->dd_handle;
160 	int ret;
161 
162 	/*
163 	 * There is no meaningful way to get the status of the programming while
164 	 * it is in progress, so attempting anything other than waiting for it
165 	 * to complete would be misplaced.
166 	 */
167 	ret = wait_for_completion_timeout(&priv->programming_complete,
168 					  msecs_to_jiffies(AUTO_UPDATE_TIMEOUT_MS));
169 	if (!ret)
170 		return FW_UPLOAD_ERR_TIMEOUT;
171 
172 	return FW_UPLOAD_ERR_NONE;
173 }
174 
175 static int mpfs_auto_update_verify_image(struct fw_upload *fw_uploader)
176 {
177 	struct mpfs_auto_update_priv *priv = fw_uploader->dd_handle;
178 	u32 *response_msg __free(kfree) =
179 		kzalloc(AUTO_UPDATE_FEATURE_RESP_SIZE * sizeof(*response_msg), GFP_KERNEL);
180 	struct mpfs_mss_response *response __free(kfree) =
181 		kzalloc(sizeof(struct mpfs_mss_response), GFP_KERNEL);
182 	struct mpfs_mss_msg *message __free(kfree) =
183 		kzalloc(sizeof(struct mpfs_mss_msg), GFP_KERNEL);
184 	int ret;
185 
186 	if (!response_msg || !response || !message)
187 		return -ENOMEM;
188 
189 	/*
190 	 * The system controller can verify that an image in the flash is valid.
191 	 * Rather than duplicate the check in this driver, call the relevant
192 	 * service from the system controller instead.
193 	 * This service has no command data and no response data. It overloads
194 	 * mbox_offset with the image index in the flash's SPI directory where
195 	 * the bitstream is located.
196 	 */
197 	response->resp_msg = response_msg;
198 	response->resp_size = AUTO_UPDATE_AUTHENTICATE_RESP_SIZE;
199 	message->cmd_opcode = AUTO_UPDATE_AUTHENTICATE_CMD_OPCODE;
200 	message->cmd_data_size = AUTO_UPDATE_AUTHENTICATE_CMD_DATA_SIZE;
201 	message->response = response;
202 	message->cmd_data = AUTO_UPDATE_AUTHENTICATE_CMD_DATA;
203 	message->mbox_offset = AUTO_UPDATE_UPGRADE_INDEX;
204 	message->resp_offset = AUTO_UPDATE_DEFAULT_RESP_OFFSET;
205 
206 	dev_info(priv->dev, "Running verification of Upgrade Image\n");
207 	ret = mpfs_blocking_transaction(priv->sys_controller, message);
208 	if (ret | response->resp_status) {
209 		dev_warn(priv->dev, "Verification of Upgrade Image failed!\n");
210 		return ret ? ret : -EBADMSG;
211 	}
212 
213 	dev_info(priv->dev, "Verification of Upgrade Image passed!\n");
214 
215 	return 0;
216 }
217 
218 static int mpfs_auto_update_set_image_address(struct mpfs_auto_update_priv *priv,
219 					      u32 image_address, loff_t directory_address)
220 {
221 	struct erase_info erase;
222 	size_t erase_size = round_up(AUTO_UPDATE_DIRECTORY_SIZE, (u64)priv->flash->erasesize);
223 	size_t bytes_written = 0, bytes_read = 0;
224 	char *buffer __free(kfree) = kzalloc(erase_size, GFP_KERNEL);
225 	int ret;
226 
227 	if (!buffer)
228 		return -ENOMEM;
229 
230 	erase.addr = AUTO_UPDATE_DIRECTORY_BASE;
231 	erase.len = erase_size;
232 
233 	/*
234 	 * We need to write the "SPI DIRECTORY" to the first 1 KiB, telling
235 	 * the system controller where to find the actual bitstream. Since
236 	 * this is spi-nor, we have to read the first eraseblock, erase that
237 	 * portion of the flash, modify the data and then write it back.
238 	 * There's no need to do this though if things are already the way they
239 	 * should be, so check and save the write in that case.
240 	 */
241 	ret = mtd_read(priv->flash, AUTO_UPDATE_DIRECTORY_BASE, erase_size, &bytes_read,
242 		       (u_char *)buffer);
243 	if (ret)
244 		return ret;
245 
246 	if (bytes_read != erase_size)
247 		return -EIO;
248 
249 	if ((*(u32 *)(buffer + AUTO_UPDATE_UPGRADE_DIRECTORY) == image_address) &&
250 	    !(*(u32 *)(buffer + AUTO_UPDATE_BLANK_DIRECTORY)))
251 		return 0;
252 
253 	ret = mtd_erase(priv->flash, &erase);
254 	if (ret)
255 		return ret;
256 
257 	/*
258 	 * Populate the image address and then zero out the next directory so
259 	 * that the system controller doesn't complain if in "Single Image"
260 	 * mode.
261 	 */
262 	memcpy(buffer + AUTO_UPDATE_UPGRADE_DIRECTORY, &image_address,
263 	       AUTO_UPDATE_DIRECTORY_WIDTH);
264 	memset(buffer + AUTO_UPDATE_BLANK_DIRECTORY, 0x0, AUTO_UPDATE_DIRECTORY_WIDTH);
265 
266 	dev_info(priv->dev, "Writing the image address (0x%x) to the flash directory (0x%llx)\n",
267 		 image_address, directory_address);
268 
269 	ret = mtd_write(priv->flash, 0x0, erase_size, &bytes_written, (u_char *)buffer);
270 	if (ret)
271 		return ret;
272 
273 	if (bytes_written != erase_size)
274 		return -EIO;
275 
276 	return 0;
277 }
278 
279 static int mpfs_auto_update_write_bitstream(struct fw_upload *fw_uploader, const u8 *data,
280 					    u32 offset, u32 size, u32 *written)
281 {
282 	struct mpfs_auto_update_priv *priv = fw_uploader->dd_handle;
283 	struct erase_info erase;
284 	loff_t directory_address = AUTO_UPDATE_UPGRADE_DIRECTORY;
285 	size_t erase_size = AUTO_UPDATE_DIRECTORY_SIZE;
286 	size_t bytes_written = 0;
287 	bool is_info = mpfs_auto_update_is_bitstream_info(data, size);
288 	u32 image_address;
289 	int ret;
290 
291 	erase_size = round_up(erase_size, (u64)priv->flash->erasesize);
292 
293 	if (is_info)
294 		image_address = AUTO_UPDATE_INFO_BASE;
295 	else
296 		image_address = AUTO_UPDATE_BITSTREAM_BASE +
297 				AUTO_UPDATE_UPGRADE_INDEX * priv->size_per_bitstream;
298 
299 	/*
300 	 * For bitstream info, the descriptor is written to a fixed offset,
301 	 * so there is no need to set the image address.
302 	 */
303 	if (!is_info) {
304 		ret = mpfs_auto_update_set_image_address(priv, image_address, directory_address);
305 		if (ret) {
306 			dev_err(priv->dev, "failed to set image address in the SPI directory: %d\n", ret);
307 			return ret;
308 		}
309 	} else {
310 		if (size > AUTO_UPDATE_INFO_SIZE) {
311 			dev_err(priv->dev, "bitstream info exceeds permitted size\n");
312 			return -ENOSPC;
313 		}
314 	}
315 
316 	/*
317 	 * Now the .spi image itself can be written to the flash. Preservation
318 	 * of contents here is not important here, unlike the spi "directory"
319 	 * which must be RMWed.
320 	 */
321 	erase.len = round_up(size, (size_t)priv->flash->erasesize);
322 	erase.addr = image_address;
323 
324 	dev_info(priv->dev, "Erasing the flash at address (0x%x)\n", image_address);
325 	ret = mtd_erase(priv->flash, &erase);
326 	if (ret)
327 		return ret;
328 
329 	/*
330 	 * No parsing etc of the bitstream is required. The system controller
331 	 * will do all of that itself - including verifying that the bitstream
332 	 * is valid.
333 	 */
334 	dev_info(priv->dev, "Writing the image to the flash at address (0x%x)\n", image_address);
335 	ret = mtd_write(priv->flash, (loff_t)image_address, size, &bytes_written, data);
336 	if (ret)
337 		return ret;
338 
339 	if (bytes_written != size)
340 		return -EIO;
341 
342 	*written = bytes_written;
343 	dev_info(priv->dev, "Wrote 0x%zx bytes to the flash\n", bytes_written);
344 
345 	return 0;
346 }
347 
348 static enum fw_upload_err mpfs_auto_update_write(struct fw_upload *fw_uploader, const u8 *data,
349 						 u32 offset, u32 size, u32 *written)
350 {
351 	struct mpfs_auto_update_priv *priv = fw_uploader->dd_handle;
352 	enum fw_upload_err err = FW_UPLOAD_ERR_NONE;
353 	int ret;
354 
355 	reinit_completion(&priv->programming_complete);
356 
357 	ret = mpfs_auto_update_write_bitstream(fw_uploader, data, offset, size, written);
358 	if (ret) {
359 		err = FW_UPLOAD_ERR_RW_ERROR;
360 		goto out;
361 	}
362 
363 	if (priv->cancel_request) {
364 		err = FW_UPLOAD_ERR_CANCELED;
365 		goto out;
366 	}
367 
368 	if (mpfs_auto_update_is_bitstream_info(data, size))
369 		goto out;
370 
371 	ret = mpfs_auto_update_verify_image(fw_uploader);
372 	if (ret)
373 		err = FW_UPLOAD_ERR_FW_INVALID;
374 
375 out:
376 	complete(&priv->programming_complete);
377 
378 	return err;
379 }
380 
381 static const struct fw_upload_ops mpfs_auto_update_ops = {
382 	.prepare = mpfs_auto_update_prepare,
383 	.write = mpfs_auto_update_write,
384 	.poll_complete = mpfs_auto_update_poll_complete,
385 	.cancel = mpfs_auto_update_cancel,
386 };
387 
388 static int mpfs_auto_update_available(struct mpfs_auto_update_priv *priv)
389 {
390 	u32 *response_msg __free(kfree) =
391 		kzalloc(AUTO_UPDATE_FEATURE_RESP_SIZE * sizeof(*response_msg), GFP_KERNEL);
392 	struct mpfs_mss_response *response __free(kfree) =
393 		kzalloc(sizeof(struct mpfs_mss_response), GFP_KERNEL);
394 	struct mpfs_mss_msg *message __free(kfree) =
395 		kzalloc(sizeof(struct mpfs_mss_msg), GFP_KERNEL);
396 	int ret;
397 
398 	if (!response_msg || !response || !message)
399 		return -ENOMEM;
400 
401 	/*
402 	 * To verify that Auto Update is possible, the "Query Security Service
403 	 * Request" is performed.
404 	 * This service has no command data & does not overload mbox_offset.
405 	 */
406 	response->resp_msg = response_msg;
407 	response->resp_size = AUTO_UPDATE_FEATURE_RESP_SIZE;
408 	message->cmd_opcode = AUTO_UPDATE_FEATURE_CMD_OPCODE;
409 	message->cmd_data_size = AUTO_UPDATE_FEATURE_CMD_DATA_SIZE;
410 	message->response = response;
411 	message->cmd_data = AUTO_UPDATE_FEATURE_CMD_DATA;
412 	message->mbox_offset = AUTO_UPDATE_DEFAULT_MBOX_OFFSET;
413 	message->resp_offset = AUTO_UPDATE_DEFAULT_RESP_OFFSET;
414 
415 	ret = mpfs_blocking_transaction(priv->sys_controller, message);
416 	if (ret)
417 		return ret;
418 
419 	/*
420 	 * Currently, the system controller's firmware does not generate any
421 	 * interrupts for failed services, so mpfs_blocking_transaction() should
422 	 * time out & therefore return an error.
423 	 * Hitting this check is highly unlikely at present, but if the system
424 	 * controller's behaviour changes so that it does generate interrupts
425 	 * for failed services, it will be required.
426 	 */
427 	if (response->resp_status)
428 		return -EIO;
429 
430 	/*
431 	 * Bit 5 of byte 1 is "UL_Auto Update" & if it is set, Auto Update is
432 	 * not possible.
433 	 */
434 	if (response_msg[1] & AUTO_UPDATE_FEATURE_ENABLED)
435 		return -EPERM;
436 
437 	return 0;
438 }
439 
440 static int mpfs_auto_update_probe(struct platform_device *pdev)
441 {
442 	struct device *dev = &pdev->dev;
443 	struct mpfs_auto_update_priv *priv;
444 	struct fw_upload *fw_uploader;
445 	int ret;
446 
447 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
448 	if (!priv)
449 		return -ENOMEM;
450 
451 	priv->sys_controller = mpfs_sys_controller_get(dev);
452 	if (IS_ERR(priv->sys_controller))
453 		return dev_err_probe(dev, PTR_ERR(priv->sys_controller),
454 				     "Could not register as a sub device of the system controller\n");
455 
456 	priv->dev = dev;
457 	platform_set_drvdata(pdev, priv);
458 
459 	ret = mpfs_auto_update_available(priv);
460 	if (ret)
461 		return dev_err_probe(dev, ret,
462 				     "The current bitstream does not support auto-update\n");
463 
464 	init_completion(&priv->programming_complete);
465 
466 	fw_uploader = firmware_upload_register(THIS_MODULE, dev, "mpfs-auto-update",
467 					       &mpfs_auto_update_ops, priv);
468 	if (IS_ERR(fw_uploader))
469 		return dev_err_probe(dev, PTR_ERR(fw_uploader),
470 				     "Failed to register the bitstream uploader\n");
471 
472 	priv->fw_uploader = fw_uploader;
473 
474 	return 0;
475 }
476 
477 static void mpfs_auto_update_remove(struct platform_device *pdev)
478 {
479 	struct mpfs_auto_update_priv *priv = platform_get_drvdata(pdev);
480 
481 	firmware_upload_unregister(priv->fw_uploader);
482 }
483 
484 static struct platform_driver mpfs_auto_update_driver = {
485 	.driver = {
486 		.name = "mpfs-auto-update",
487 	},
488 	.probe = mpfs_auto_update_probe,
489 	.remove_new = mpfs_auto_update_remove,
490 };
491 module_platform_driver(mpfs_auto_update_driver);
492 
493 MODULE_LICENSE("GPL");
494 MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
495 MODULE_DESCRIPTION("PolarFire SoC Auto Update FPGA reprogramming");
496