Linux Audio

Check our new training course

Loading...
Note: File does not exist in v3.1.
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * BOOTROM Greybus driver.
  4 *
  5 * Copyright 2016 Google Inc.
  6 * Copyright 2016 Linaro Ltd.
  7 */
  8
  9#include <linux/firmware.h>
 10#include <linux/jiffies.h>
 11#include <linux/mutex.h>
 12#include <linux/workqueue.h>
 13
 14#include "greybus.h"
 15#include "firmware.h"
 16
 17/* Timeout, in jiffies, within which the next request must be received */
 18#define NEXT_REQ_TIMEOUT_MS	1000
 19
 20/*
 21 * FIXME: Reduce this timeout once svc core handles parallel processing of
 22 * events from the SVC, which are handled sequentially today.
 23 */
 24#define MODE_SWITCH_TIMEOUT_MS	10000
 25
 26enum next_request_type {
 27	NEXT_REQ_FIRMWARE_SIZE,
 28	NEXT_REQ_GET_FIRMWARE,
 29	NEXT_REQ_READY_TO_BOOT,
 30	NEXT_REQ_MODE_SWITCH,
 31};
 32
 33struct gb_bootrom {
 34	struct gb_connection	*connection;
 35	const struct firmware	*fw;
 36	u8			protocol_major;
 37	u8			protocol_minor;
 38	enum next_request_type	next_request;
 39	struct delayed_work	dwork;
 40	struct mutex		mutex; /* Protects bootrom->fw */
 41};
 42
 43static void free_firmware(struct gb_bootrom *bootrom)
 44{
 45	if (!bootrom->fw)
 46		return;
 47
 48	release_firmware(bootrom->fw);
 49	bootrom->fw = NULL;
 50}
 51
 52static void gb_bootrom_timedout(struct work_struct *work)
 53{
 54	struct delayed_work *dwork = to_delayed_work(work);
 55	struct gb_bootrom *bootrom = container_of(dwork,
 56						  struct gb_bootrom, dwork);
 57	struct device *dev = &bootrom->connection->bundle->dev;
 58	const char *reason;
 59
 60	switch (bootrom->next_request) {
 61	case NEXT_REQ_FIRMWARE_SIZE:
 62		reason = "Firmware Size Request";
 63		break;
 64	case NEXT_REQ_GET_FIRMWARE:
 65		reason = "Get Firmware Request";
 66		break;
 67	case NEXT_REQ_READY_TO_BOOT:
 68		reason = "Ready to Boot Request";
 69		break;
 70	case NEXT_REQ_MODE_SWITCH:
 71		reason = "Interface Mode Switch";
 72		break;
 73	default:
 74		reason = NULL;
 75		dev_err(dev, "Invalid next-request: %u", bootrom->next_request);
 76		break;
 77	}
 78
 79	dev_err(dev, "Timed out waiting for %s from the Module\n", reason);
 80
 81	mutex_lock(&bootrom->mutex);
 82	free_firmware(bootrom);
 83	mutex_unlock(&bootrom->mutex);
 84
 85	/* TODO: Power-off Module ? */
 86}
 87
 88static void gb_bootrom_set_timeout(struct gb_bootrom *bootrom,
 89			enum next_request_type next, unsigned long timeout)
 90{
 91	bootrom->next_request = next;
 92	schedule_delayed_work(&bootrom->dwork, msecs_to_jiffies(timeout));
 93}
 94
 95static void gb_bootrom_cancel_timeout(struct gb_bootrom *bootrom)
 96{
 97	cancel_delayed_work_sync(&bootrom->dwork);
 98}
 99
100/*
101 * The es2 chip doesn't have VID/PID programmed into the hardware and we need to
102 * hack that up to distinguish different modules and their firmware blobs.
103 *
104 * This fetches VID/PID (over bootrom protocol) for es2 chip only, when VID/PID
105 * already sent during hotplug are 0.
106 *
107 * Otherwise, we keep intf->vendor_id/product_id same as what's passed
108 * during hotplug.
109 */
110static void bootrom_es2_fixup_vid_pid(struct gb_bootrom *bootrom)
111{
112	struct gb_bootrom_get_vid_pid_response response;
113	struct gb_connection *connection = bootrom->connection;
114	struct gb_interface *intf = connection->bundle->intf;
115	int ret;
116
117	if (!(intf->quirks & GB_INTERFACE_QUIRK_NO_GMP_IDS))
118		return;
119
120	ret = gb_operation_sync(connection, GB_BOOTROM_TYPE_GET_VID_PID,
121				NULL, 0, &response, sizeof(response));
122	if (ret) {
123		dev_err(&connection->bundle->dev,
124			"Bootrom get vid/pid operation failed (%d)\n", ret);
125		return;
126	}
127
128	/*
129	 * NOTE: This is hacked, so that the same values of VID/PID can be used
130	 * by next firmware level as well. The uevent for bootrom will still
131	 * have VID/PID as 0, though after this point the sysfs files will start
132	 * showing the updated values. But yeah, that's a bit racy as the same
133	 * sysfs files would be showing 0 before this point.
134	 */
135	intf->vendor_id = le32_to_cpu(response.vendor_id);
136	intf->product_id = le32_to_cpu(response.product_id);
137
138	dev_dbg(&connection->bundle->dev, "Bootrom got vid (0x%x)/pid (0x%x)\n",
139		intf->vendor_id, intf->product_id);
140}
141
142/* This returns path of the firmware blob on the disk */
143static int find_firmware(struct gb_bootrom *bootrom, u8 stage)
144{
145	struct gb_connection *connection = bootrom->connection;
146	struct gb_interface *intf = connection->bundle->intf;
147	char firmware_name[49];
148	int rc;
149
150	/* Already have a firmware, free it */
151	free_firmware(bootrom);
152
153	/* Bootrom protocol is only supported for loading Stage 2 firmware */
154	if (stage != 2) {
155		dev_err(&connection->bundle->dev, "Invalid boot stage: %u\n",
156			stage);
157		return -EINVAL;
158	}
159
160	/*
161	 * Create firmware name
162	 *
163	 * XXX Name it properly..
164	 */
165	snprintf(firmware_name, sizeof(firmware_name),
166		 FW_NAME_PREFIX "%08x_%08x_%08x_%08x_s2l.tftf",
167		 intf->ddbl1_manufacturer_id, intf->ddbl1_product_id,
168		 intf->vendor_id, intf->product_id);
169
170	// FIXME:
171	// Turn to dev_dbg later after everyone has valid bootloaders with good
172	// ids, but leave this as dev_info for now to make it easier to track
173	// down "empty" vid/pid modules.
174	dev_info(&connection->bundle->dev, "Firmware file '%s' requested\n",
175		 firmware_name);
176
177	rc = request_firmware(&bootrom->fw, firmware_name,
178		&connection->bundle->dev);
179	if (rc) {
180		dev_err(&connection->bundle->dev,
181			"failed to find %s firmware (%d)\n", firmware_name, rc);
182	}
183
184	return rc;
185}
186
187static int gb_bootrom_firmware_size_request(struct gb_operation *op)
188{
189	struct gb_bootrom *bootrom = gb_connection_get_data(op->connection);
190	struct gb_bootrom_firmware_size_request *size_request =
191		op->request->payload;
192	struct gb_bootrom_firmware_size_response *size_response;
193	struct device *dev = &op->connection->bundle->dev;
194	int ret;
195
196	/* Disable timeouts */
197	gb_bootrom_cancel_timeout(bootrom);
198
199	if (op->request->payload_size != sizeof(*size_request)) {
200		dev_err(dev, "%s: illegal size of firmware size request (%zu != %zu)\n",
201			__func__, op->request->payload_size,
202			sizeof(*size_request));
203		ret = -EINVAL;
204		goto queue_work;
205	}
206
207	mutex_lock(&bootrom->mutex);
208
209	ret = find_firmware(bootrom, size_request->stage);
210	if (ret)
211		goto unlock;
212
213	if (!gb_operation_response_alloc(op, sizeof(*size_response),
214					 GFP_KERNEL)) {
215		dev_err(dev, "%s: error allocating response\n", __func__);
216		free_firmware(bootrom);
217		ret = -ENOMEM;
218		goto unlock;
219	}
220
221	size_response = op->response->payload;
222	size_response->size = cpu_to_le32(bootrom->fw->size);
223
224	dev_dbg(dev, "%s: firmware size %d bytes\n",
225		__func__, size_response->size);
226
227unlock:
228	mutex_unlock(&bootrom->mutex);
229
230queue_work:
231	if (!ret) {
232		/* Refresh timeout */
233		gb_bootrom_set_timeout(bootrom, NEXT_REQ_GET_FIRMWARE,
234				       NEXT_REQ_TIMEOUT_MS);
235	}
236
237	return ret;
238}
239
240static int gb_bootrom_get_firmware(struct gb_operation *op)
241{
242	struct gb_bootrom *bootrom = gb_connection_get_data(op->connection);
243	const struct firmware *fw;
244	struct gb_bootrom_get_firmware_request *firmware_request;
245	struct gb_bootrom_get_firmware_response *firmware_response;
246	struct device *dev = &op->connection->bundle->dev;
247	unsigned int offset, size;
248	enum next_request_type next_request;
249	int ret = 0;
250
251	/* Disable timeouts */
252	gb_bootrom_cancel_timeout(bootrom);
253
254	if (op->request->payload_size != sizeof(*firmware_request)) {
255		dev_err(dev, "%s: Illegal size of get firmware request (%zu %zu)\n",
256			__func__, op->request->payload_size,
257			sizeof(*firmware_request));
258		ret = -EINVAL;
259		goto queue_work;
260	}
261
262	mutex_lock(&bootrom->mutex);
263
264	fw = bootrom->fw;
265	if (!fw) {
266		dev_err(dev, "%s: firmware not available\n", __func__);
267		ret = -EINVAL;
268		goto unlock;
269	}
270
271	firmware_request = op->request->payload;
272	offset = le32_to_cpu(firmware_request->offset);
273	size = le32_to_cpu(firmware_request->size);
274
275	if (offset >= fw->size || size > fw->size - offset) {
276		dev_warn(dev, "bad firmware request (offs = %u, size = %u)\n",
277				offset, size);
278		ret = -EINVAL;
279		goto unlock;
280	}
281
282	if (!gb_operation_response_alloc(op, sizeof(*firmware_response) + size,
283					 GFP_KERNEL)) {
284		dev_err(dev, "%s: error allocating response\n", __func__);
285		ret = -ENOMEM;
286		goto unlock;
287	}
288
289	firmware_response = op->response->payload;
290	memcpy(firmware_response->data, fw->data + offset, size);
291
292	dev_dbg(dev, "responding with firmware (offs = %u, size = %u)\n",
293		offset, size);
294
295unlock:
296	mutex_unlock(&bootrom->mutex);
297
298queue_work:
299	/* Refresh timeout */
300	if (!ret && (offset + size == fw->size))
301		next_request = NEXT_REQ_READY_TO_BOOT;
302	else
303		next_request = NEXT_REQ_GET_FIRMWARE;
304
305	gb_bootrom_set_timeout(bootrom, next_request, NEXT_REQ_TIMEOUT_MS);
306
307	return ret;
308}
309
310static int gb_bootrom_ready_to_boot(struct gb_operation *op)
311{
312	struct gb_connection *connection = op->connection;
313	struct gb_bootrom *bootrom = gb_connection_get_data(connection);
314	struct gb_bootrom_ready_to_boot_request *rtb_request;
315	struct device *dev = &connection->bundle->dev;
316	u8 status;
317	int ret = 0;
318
319	/* Disable timeouts */
320	gb_bootrom_cancel_timeout(bootrom);
321
322	if (op->request->payload_size != sizeof(*rtb_request)) {
323		dev_err(dev, "%s: Illegal size of ready to boot request (%zu %zu)\n",
324			__func__, op->request->payload_size,
325			sizeof(*rtb_request));
326		ret = -EINVAL;
327		goto queue_work;
328	}
329
330	rtb_request = op->request->payload;
331	status = rtb_request->status;
332
333	/* Return error if the blob was invalid */
334	if (status == GB_BOOTROM_BOOT_STATUS_INVALID) {
335		ret = -EINVAL;
336		goto queue_work;
337	}
338
339	/*
340	 * XXX Should we return error for insecure firmware?
341	 */
342	dev_dbg(dev, "ready to boot: 0x%x, 0\n", status);
343
344queue_work:
345	/*
346	 * Refresh timeout, the Interface shall load the new personality and
347	 * send a new hotplug request, which shall get rid of the bootrom
348	 * connection. As that can take some time, increase the timeout a bit.
349	 */
350	gb_bootrom_set_timeout(bootrom, NEXT_REQ_MODE_SWITCH,
351			       MODE_SWITCH_TIMEOUT_MS);
352
353	return ret;
354}
355
356static int gb_bootrom_request_handler(struct gb_operation *op)
357{
358	u8 type = op->type;
359
360	switch (type) {
361	case GB_BOOTROM_TYPE_FIRMWARE_SIZE:
362		return gb_bootrom_firmware_size_request(op);
363	case GB_BOOTROM_TYPE_GET_FIRMWARE:
364		return gb_bootrom_get_firmware(op);
365	case GB_BOOTROM_TYPE_READY_TO_BOOT:
366		return gb_bootrom_ready_to_boot(op);
367	default:
368		dev_err(&op->connection->bundle->dev,
369			"unsupported request: %u\n", type);
370		return -EINVAL;
371	}
372}
373
374static int gb_bootrom_get_version(struct gb_bootrom *bootrom)
375{
376	struct gb_bundle *bundle = bootrom->connection->bundle;
377	struct gb_bootrom_version_request request;
378	struct gb_bootrom_version_response response;
379	int ret;
380
381	request.major = GB_BOOTROM_VERSION_MAJOR;
382	request.minor = GB_BOOTROM_VERSION_MINOR;
383
384	ret = gb_operation_sync(bootrom->connection,
385				GB_BOOTROM_TYPE_VERSION,
386				&request, sizeof(request), &response,
387				sizeof(response));
388	if (ret) {
389		dev_err(&bundle->dev,
390				"failed to get protocol version: %d\n",
391				ret);
392		return ret;
393	}
394
395	if (response.major > request.major) {
396		dev_err(&bundle->dev,
397				"unsupported major protocol version (%u > %u)\n",
398				response.major, request.major);
399		return -ENOTSUPP;
400	}
401
402	bootrom->protocol_major = response.major;
403	bootrom->protocol_minor = response.minor;
404
405	dev_dbg(&bundle->dev, "%s - %u.%u\n", __func__, response.major,
406			response.minor);
407
408	return 0;
409}
410
411static int gb_bootrom_probe(struct gb_bundle *bundle,
412					const struct greybus_bundle_id *id)
413{
414	struct greybus_descriptor_cport *cport_desc;
415	struct gb_connection *connection;
416	struct gb_bootrom *bootrom;
417	int ret;
418
419	if (bundle->num_cports != 1)
420		return -ENODEV;
421
422	cport_desc = &bundle->cport_desc[0];
423	if (cport_desc->protocol_id != GREYBUS_PROTOCOL_BOOTROM)
424		return -ENODEV;
425
426	bootrom = kzalloc(sizeof(*bootrom), GFP_KERNEL);
427	if (!bootrom)
428		return -ENOMEM;
429
430	connection = gb_connection_create(bundle,
431						le16_to_cpu(cport_desc->id),
432						gb_bootrom_request_handler);
433	if (IS_ERR(connection)) {
434		ret = PTR_ERR(connection);
435		goto err_free_bootrom;
436	}
437
438	gb_connection_set_data(connection, bootrom);
439
440	bootrom->connection = connection;
441
442	mutex_init(&bootrom->mutex);
443	INIT_DELAYED_WORK(&bootrom->dwork, gb_bootrom_timedout);
444	greybus_set_drvdata(bundle, bootrom);
445
446	ret = gb_connection_enable_tx(connection);
447	if (ret)
448		goto err_connection_destroy;
449
450	ret = gb_bootrom_get_version(bootrom);
451	if (ret)
452		goto err_connection_disable;
453
454	bootrom_es2_fixup_vid_pid(bootrom);
455
456	ret = gb_connection_enable(connection);
457	if (ret)
458		goto err_connection_disable;
459
460	/* Refresh timeout */
461	gb_bootrom_set_timeout(bootrom, NEXT_REQ_FIRMWARE_SIZE,
462			       NEXT_REQ_TIMEOUT_MS);
463
464	/* Tell bootrom we're ready. */
465	ret = gb_operation_sync(connection, GB_BOOTROM_TYPE_AP_READY, NULL, 0,
466				NULL, 0);
467	if (ret) {
468		dev_err(&connection->bundle->dev,
469				"failed to send AP READY: %d\n", ret);
470		goto err_cancel_timeout;
471	}
472
473	dev_dbg(&bundle->dev, "AP_READY sent\n");
474
475	return 0;
476
477err_cancel_timeout:
478	gb_bootrom_cancel_timeout(bootrom);
479err_connection_disable:
480	gb_connection_disable(connection);
481err_connection_destroy:
482	gb_connection_destroy(connection);
483err_free_bootrom:
484	kfree(bootrom);
485
486	return ret;
487}
488
489static void gb_bootrom_disconnect(struct gb_bundle *bundle)
490{
491	struct gb_bootrom *bootrom = greybus_get_drvdata(bundle);
492
493	dev_dbg(&bundle->dev, "%s\n", __func__);
494
495	gb_connection_disable(bootrom->connection);
496
497	/* Disable timeouts */
498	gb_bootrom_cancel_timeout(bootrom);
499
500	/*
501	 * Release firmware:
502	 *
503	 * As the connection and the delayed work are already disabled, we don't
504	 * need to lock access to bootrom->fw here.
505	 */
506	free_firmware(bootrom);
507
508	gb_connection_destroy(bootrom->connection);
509	kfree(bootrom);
510}
511
512static const struct greybus_bundle_id gb_bootrom_id_table[] = {
513	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_BOOTROM) },
514	{ }
515};
516
517static struct greybus_driver gb_bootrom_driver = {
518	.name		= "bootrom",
519	.probe		= gb_bootrom_probe,
520	.disconnect	= gb_bootrom_disconnect,
521	.id_table	= gb_bootrom_id_table,
522};
523
524module_greybus_driver(gb_bootrom_driver);
525
526MODULE_LICENSE("GPL v2");