xref: /linux/drivers/firmware/microchip/mpfs-auto-update.c (revision bfe62a454542cfad3379f6ef5680b125f41e20f4)
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 struct mpfs_auto_update_priv {
80 	struct mpfs_sys_controller *sys_controller;
81 	struct device *dev;
82 	struct mtd_info *flash;
83 	struct fw_upload *fw_uploader;
84 	size_t size_per_bitstream;
85 	bool cancel_request;
86 };
87 
mpfs_auto_update_is_bitstream_info(const u8 * data,u32 size)88 static bool mpfs_auto_update_is_bitstream_info(const u8 *data, u32 size)
89 {
90 	if (size < 4)
91 		return false;
92 
93 	if (data[0] == 0x4d && data[1] == 0x43 && data[2] == 0x48 && data[3] == 0x50)
94 		return true;
95 
96 	return false;
97 }
98 
mpfs_auto_update_prepare(struct fw_upload * fw_uploader,const u8 * data,u32 size)99 static enum fw_upload_err mpfs_auto_update_prepare(struct fw_upload *fw_uploader, const u8 *data,
100 						   u32 size)
101 {
102 	struct mpfs_auto_update_priv *priv = fw_uploader->dd_handle;
103 	size_t erase_size = AUTO_UPDATE_DIRECTORY_SIZE;
104 
105 	/*
106 	 * Verifying the Golden Image is idealistic. It will be evaluated
107 	 * against the currently programmed image and thus may fail - due to
108 	 * either rollback protection (if its an older version than that in use)
109 	 * or if the version is the same as that of the in-use image.
110 	 * Extracting the information as to why a failure occurred is not
111 	 * currently possible due to limitations of the system controller
112 	 * driver. If those are fixed, verification of the Golden Image should
113 	 * be added here.
114 	 */
115 
116 	erase_size = round_up(erase_size, (u64)priv->flash->erasesize);
117 
118 	/*
119 	 * We need to calculate if we have enough space in the flash for the
120 	 * new image.
121 	 * First, chop off the first 1 KiB as it's reserved for the directory.
122 	 * The 1 MiB reserved for design info needs to be ignored also.
123 	 * All that remains is carved into 3 & rounded down to the erasesize.
124 	 * If this is smaller than the image size, we abort.
125 	 * There's also no need to consume more than 20 MiB per image.
126 	 */
127 	priv->size_per_bitstream = priv->flash->size - SZ_1K - SZ_1M;
128 	priv->size_per_bitstream = round_down(priv->size_per_bitstream / 3, erase_size);
129 	if (priv->size_per_bitstream > 20 * SZ_1M)
130 		priv->size_per_bitstream = 20 * SZ_1M;
131 
132 	if (priv->size_per_bitstream < size) {
133 		dev_err(priv->dev,
134 			"flash device has insufficient capacity to store this bitstream\n");
135 		return FW_UPLOAD_ERR_INVALID_SIZE;
136 	}
137 
138 	priv->cancel_request = false;
139 
140 	return FW_UPLOAD_ERR_NONE;
141 }
142 
mpfs_auto_update_cancel(struct fw_upload * fw_uploader)143 static void mpfs_auto_update_cancel(struct fw_upload *fw_uploader)
144 {
145 	struct mpfs_auto_update_priv *priv = fw_uploader->dd_handle;
146 
147 	priv->cancel_request = true;
148 }
149 
mpfs_auto_update_poll_complete(struct fw_upload * fw_uploader)150 static enum fw_upload_err mpfs_auto_update_poll_complete(struct fw_upload *fw_uploader)
151 {
152 	return FW_UPLOAD_ERR_NONE;
153 }
154 
mpfs_auto_update_verify_image(struct fw_upload * fw_uploader)155 static int mpfs_auto_update_verify_image(struct fw_upload *fw_uploader)
156 {
157 	struct mpfs_auto_update_priv *priv = fw_uploader->dd_handle;
158 	u32 *response_msg __free(kfree) =
159 		kzalloc(AUTO_UPDATE_FEATURE_RESP_SIZE * sizeof(*response_msg), GFP_KERNEL);
160 	struct mpfs_mss_response *response __free(kfree) =
161 		kzalloc_obj(struct mpfs_mss_response);
162 	struct mpfs_mss_msg *message __free(kfree) =
163 		kzalloc_obj(struct mpfs_mss_msg);
164 	int ret;
165 
166 	if (!response_msg || !response || !message)
167 		return -ENOMEM;
168 
169 	/*
170 	 * The system controller can verify that an image in the flash is valid.
171 	 * Rather than duplicate the check in this driver, call the relevant
172 	 * service from the system controller instead.
173 	 * This service has no command data and no response data. It overloads
174 	 * mbox_offset with the image index in the flash's SPI directory where
175 	 * the bitstream is located.
176 	 */
177 	response->resp_msg = response_msg;
178 	response->resp_size = AUTO_UPDATE_AUTHENTICATE_RESP_SIZE;
179 	message->cmd_opcode = AUTO_UPDATE_AUTHENTICATE_CMD_OPCODE;
180 	message->cmd_data_size = AUTO_UPDATE_AUTHENTICATE_CMD_DATA_SIZE;
181 	message->response = response;
182 	message->cmd_data = AUTO_UPDATE_AUTHENTICATE_CMD_DATA;
183 	message->mbox_offset = AUTO_UPDATE_UPGRADE_INDEX;
184 	message->resp_offset = AUTO_UPDATE_DEFAULT_RESP_OFFSET;
185 
186 	dev_info(priv->dev, "Running verification of Upgrade Image\n");
187 	ret = mpfs_blocking_transaction(priv->sys_controller, message);
188 	if (ret | response->resp_status) {
189 		dev_warn(priv->dev, "Verification of Upgrade Image failed!\n");
190 		return ret ? ret : -EBADMSG;
191 	}
192 
193 	dev_info(priv->dev, "Verification of Upgrade Image passed!\n");
194 
195 	return 0;
196 }
197 
mpfs_auto_update_set_image_address(struct mpfs_auto_update_priv * priv,u32 image_address,loff_t directory_address)198 static int mpfs_auto_update_set_image_address(struct mpfs_auto_update_priv *priv,
199 					      u32 image_address, loff_t directory_address)
200 {
201 	struct erase_info erase;
202 	size_t erase_size = round_up(AUTO_UPDATE_DIRECTORY_SIZE, (u64)priv->flash->erasesize);
203 	size_t bytes_written = 0, bytes_read = 0;
204 	char *buffer __free(kfree) = kzalloc(erase_size, GFP_KERNEL);
205 	int ret;
206 
207 	if (!buffer)
208 		return -ENOMEM;
209 
210 	erase.addr = AUTO_UPDATE_DIRECTORY_BASE;
211 	erase.len = erase_size;
212 
213 	/*
214 	 * We need to write the "SPI DIRECTORY" to the first 1 KiB, telling
215 	 * the system controller where to find the actual bitstream. Since
216 	 * this is spi-nor, we have to read the first eraseblock, erase that
217 	 * portion of the flash, modify the data and then write it back.
218 	 * There's no need to do this though if things are already the way they
219 	 * should be, so check and save the write in that case.
220 	 */
221 	ret = mtd_read(priv->flash, AUTO_UPDATE_DIRECTORY_BASE, erase_size, &bytes_read,
222 		       (u_char *)buffer);
223 	if (ret)
224 		return ret;
225 
226 	if (bytes_read != erase_size)
227 		return -EIO;
228 
229 	if ((*(u32 *)(buffer + AUTO_UPDATE_UPGRADE_DIRECTORY) == image_address) &&
230 	    !(*(u32 *)(buffer + AUTO_UPDATE_BLANK_DIRECTORY)))
231 		return 0;
232 
233 	ret = mtd_erase(priv->flash, &erase);
234 	if (ret)
235 		return ret;
236 
237 	/*
238 	 * Populate the image address and then zero out the next directory so
239 	 * that the system controller doesn't complain if in "Single Image"
240 	 * mode.
241 	 */
242 	memcpy(buffer + AUTO_UPDATE_UPGRADE_DIRECTORY, &image_address,
243 	       AUTO_UPDATE_DIRECTORY_WIDTH);
244 	memset(buffer + AUTO_UPDATE_BLANK_DIRECTORY, 0x0, AUTO_UPDATE_DIRECTORY_WIDTH);
245 
246 	dev_info(priv->dev, "Writing the image address (0x%x) to the flash directory (0x%llx)\n",
247 		 image_address, directory_address);
248 
249 	ret = mtd_write(priv->flash, 0x0, erase_size, &bytes_written, (u_char *)buffer);
250 	if (ret)
251 		return ret;
252 
253 	if (bytes_written != erase_size)
254 		return -EIO;
255 
256 	return 0;
257 }
258 
mpfs_auto_update_write_bitstream(struct fw_upload * fw_uploader,const u8 * data,u32 offset,u32 size,u32 * written)259 static int mpfs_auto_update_write_bitstream(struct fw_upload *fw_uploader, const u8 *data,
260 					    u32 offset, u32 size, u32 *written)
261 {
262 	struct mpfs_auto_update_priv *priv = fw_uploader->dd_handle;
263 	struct erase_info erase;
264 	loff_t directory_address = AUTO_UPDATE_UPGRADE_DIRECTORY;
265 	size_t erase_size = AUTO_UPDATE_DIRECTORY_SIZE;
266 	size_t bytes_written = 0;
267 	bool is_info = mpfs_auto_update_is_bitstream_info(data, size);
268 	u32 image_address;
269 	int ret;
270 
271 	erase_size = round_up(erase_size, (u64)priv->flash->erasesize);
272 
273 	if (is_info)
274 		image_address = AUTO_UPDATE_INFO_BASE;
275 	else
276 		image_address = AUTO_UPDATE_BITSTREAM_BASE +
277 				AUTO_UPDATE_UPGRADE_INDEX * priv->size_per_bitstream;
278 
279 	/*
280 	 * For bitstream info, the descriptor is written to a fixed offset,
281 	 * so there is no need to set the image address.
282 	 */
283 	if (!is_info) {
284 		ret = mpfs_auto_update_set_image_address(priv, image_address, directory_address);
285 		if (ret) {
286 			dev_err(priv->dev, "failed to set image address in the SPI directory: %d\n", ret);
287 			return ret;
288 		}
289 	} else {
290 		if (size > AUTO_UPDATE_INFO_SIZE) {
291 			dev_err(priv->dev, "bitstream info exceeds permitted size\n");
292 			return -ENOSPC;
293 		}
294 	}
295 
296 	/*
297 	 * Now the .spi image itself can be written to the flash. Preservation
298 	 * of contents here is not important here, unlike the spi "directory"
299 	 * which must be RMWed.
300 	 */
301 	erase.len = round_up(size, (size_t)priv->flash->erasesize);
302 	erase.addr = image_address;
303 
304 	dev_info(priv->dev, "Erasing the flash at address (0x%x)\n", image_address);
305 	ret = mtd_erase(priv->flash, &erase);
306 	if (ret)
307 		return ret;
308 
309 	/*
310 	 * No parsing etc of the bitstream is required. The system controller
311 	 * will do all of that itself - including verifying that the bitstream
312 	 * is valid.
313 	 */
314 	dev_info(priv->dev, "Writing the image to the flash at address (0x%x)\n", image_address);
315 	ret = mtd_write(priv->flash, (loff_t)image_address, size, &bytes_written, data);
316 	if (ret)
317 		return ret;
318 
319 	if (bytes_written != size)
320 		return -EIO;
321 
322 	*written = bytes_written;
323 	dev_info(priv->dev, "Wrote 0x%zx bytes to the flash\n", bytes_written);
324 
325 	return 0;
326 }
327 
mpfs_auto_update_write(struct fw_upload * fw_uploader,const u8 * data,u32 offset,u32 size,u32 * written)328 static enum fw_upload_err mpfs_auto_update_write(struct fw_upload *fw_uploader, const u8 *data,
329 						 u32 offset, u32 size, u32 *written)
330 {
331 	struct mpfs_auto_update_priv *priv = fw_uploader->dd_handle;
332 	int ret;
333 
334 	ret = mpfs_auto_update_write_bitstream(fw_uploader, data, offset, size, written);
335 	if (ret)
336 		return FW_UPLOAD_ERR_RW_ERROR;
337 
338 	if (priv->cancel_request)
339 		return FW_UPLOAD_ERR_CANCELED;
340 
341 	if (mpfs_auto_update_is_bitstream_info(data, size))
342 		return FW_UPLOAD_ERR_NONE;
343 
344 	ret = mpfs_auto_update_verify_image(fw_uploader);
345 	if (ret)
346 		return FW_UPLOAD_ERR_FW_INVALID;
347 
348 	return FW_UPLOAD_ERR_NONE;
349 }
350 
351 static const struct fw_upload_ops mpfs_auto_update_ops = {
352 	.prepare = mpfs_auto_update_prepare,
353 	.write = mpfs_auto_update_write,
354 	.poll_complete = mpfs_auto_update_poll_complete,
355 	.cancel = mpfs_auto_update_cancel,
356 };
357 
mpfs_auto_update_available(struct mpfs_auto_update_priv * priv)358 static int mpfs_auto_update_available(struct mpfs_auto_update_priv *priv)
359 {
360 	u32 *response_msg __free(kfree) =
361 		kzalloc(AUTO_UPDATE_FEATURE_RESP_SIZE * sizeof(*response_msg), GFP_KERNEL);
362 	struct mpfs_mss_response *response __free(kfree) =
363 		kzalloc_obj(struct mpfs_mss_response);
364 	struct mpfs_mss_msg *message __free(kfree) =
365 		kzalloc_obj(struct mpfs_mss_msg);
366 	int ret;
367 
368 	if (!response_msg || !response || !message)
369 		return -ENOMEM;
370 
371 	/*
372 	 * To verify that Auto Update is possible, the "Query Security Service
373 	 * Request" is performed.
374 	 * This service has no command data & does not overload mbox_offset.
375 	 */
376 	response->resp_msg = response_msg;
377 	response->resp_size = AUTO_UPDATE_FEATURE_RESP_SIZE;
378 	message->cmd_opcode = AUTO_UPDATE_FEATURE_CMD_OPCODE;
379 	message->cmd_data_size = AUTO_UPDATE_FEATURE_CMD_DATA_SIZE;
380 	message->response = response;
381 	message->cmd_data = AUTO_UPDATE_FEATURE_CMD_DATA;
382 	message->mbox_offset = AUTO_UPDATE_DEFAULT_MBOX_OFFSET;
383 	message->resp_offset = AUTO_UPDATE_DEFAULT_RESP_OFFSET;
384 
385 	ret = mpfs_blocking_transaction(priv->sys_controller, message);
386 	if (ret)
387 		return ret;
388 
389 	/*
390 	 * Currently, the system controller's firmware does not generate any
391 	 * interrupts for failed services, so mpfs_blocking_transaction() should
392 	 * time out & therefore return an error.
393 	 * Hitting this check is highly unlikely at present, but if the system
394 	 * controller's behaviour changes so that it does generate interrupts
395 	 * for failed services, it will be required.
396 	 */
397 	if (response->resp_status)
398 		return -EIO;
399 
400 	/*
401 	 * Bit 5 of byte 1 is "UL_IAP" & if it is set, Auto Update is
402 	 * not possible.
403 	 */
404 	if ((((u8 *)response_msg)[1] & AUTO_UPDATE_FEATURE_ENABLED))
405 		return -EPERM;
406 
407 	return 0;
408 }
409 
mpfs_auto_update_probe(struct platform_device * pdev)410 static int mpfs_auto_update_probe(struct platform_device *pdev)
411 {
412 	struct device *dev = &pdev->dev;
413 	struct mpfs_auto_update_priv *priv;
414 	struct fw_upload *fw_uploader;
415 	int ret;
416 
417 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
418 	if (!priv)
419 		return -ENOMEM;
420 
421 	priv->sys_controller = mpfs_sys_controller_get(dev);
422 	if (IS_ERR(priv->sys_controller))
423 		return dev_err_probe(dev, PTR_ERR(priv->sys_controller),
424 				     "Could not register as a sub device of the system controller\n");
425 
426 	priv->flash = mpfs_sys_controller_get_flash(priv->sys_controller);
427 	if (IS_ERR_OR_NULL(priv->flash)) {
428 		dev_dbg(dev, "No flash connected to the system controller, auto-update not supported\n");
429 		return -ENODEV;
430 	}
431 
432 	priv->dev = dev;
433 	platform_set_drvdata(pdev, priv);
434 
435 	ret = mpfs_auto_update_available(priv);
436 	if (ret)
437 		return dev_err_probe(dev, ret,
438 				     "The current bitstream does not support auto-update\n");
439 
440 	fw_uploader = firmware_upload_register(THIS_MODULE, dev, "mpfs-auto-update",
441 					       &mpfs_auto_update_ops, priv);
442 	if (IS_ERR(fw_uploader))
443 		return dev_err_probe(dev, PTR_ERR(fw_uploader),
444 				     "Failed to register the bitstream uploader\n");
445 
446 	priv->fw_uploader = fw_uploader;
447 
448 	return 0;
449 }
450 
mpfs_auto_update_remove(struct platform_device * pdev)451 static void mpfs_auto_update_remove(struct platform_device *pdev)
452 {
453 	struct mpfs_auto_update_priv *priv = platform_get_drvdata(pdev);
454 
455 	firmware_upload_unregister(priv->fw_uploader);
456 }
457 
458 static struct platform_driver mpfs_auto_update_driver = {
459 	.driver = {
460 		.name = "mpfs-auto-update",
461 	},
462 	.probe = mpfs_auto_update_probe,
463 	.remove = mpfs_auto_update_remove,
464 };
465 module_platform_driver(mpfs_auto_update_driver);
466 
467 MODULE_LICENSE("GPL");
468 MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
469 MODULE_DESCRIPTION("PolarFire SoC Auto Update FPGA reprogramming");
470