Loading...
Note: File does not exist in v3.5.6.
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Thunderbolt/USB4 retimer support.
4 *
5 * Copyright (C) 2020, Intel Corporation
6 * Authors: Kranthi Kuntala <kranthi.kuntala@intel.com>
7 * Mika Westerberg <mika.westerberg@linux.intel.com>
8 */
9
10#include <linux/delay.h>
11#include <linux/pm_runtime.h>
12#include <linux/sched/signal.h>
13
14#include "sb_regs.h"
15#include "tb.h"
16
17#define TB_MAX_RETIMER_INDEX 6
18
19static int tb_retimer_nvm_read(void *priv, unsigned int offset, void *val,
20 size_t bytes)
21{
22 struct tb_nvm *nvm = priv;
23 struct tb_retimer *rt = tb_to_retimer(nvm->dev);
24 int ret;
25
26 pm_runtime_get_sync(&rt->dev);
27
28 if (!mutex_trylock(&rt->tb->lock)) {
29 ret = restart_syscall();
30 goto out;
31 }
32
33 ret = usb4_port_retimer_nvm_read(rt->port, rt->index, offset, val, bytes);
34 mutex_unlock(&rt->tb->lock);
35
36out:
37 pm_runtime_mark_last_busy(&rt->dev);
38 pm_runtime_put_autosuspend(&rt->dev);
39
40 return ret;
41}
42
43static int tb_retimer_nvm_write(void *priv, unsigned int offset, void *val,
44 size_t bytes)
45{
46 struct tb_nvm *nvm = priv;
47 struct tb_retimer *rt = tb_to_retimer(nvm->dev);
48 int ret = 0;
49
50 if (!mutex_trylock(&rt->tb->lock))
51 return restart_syscall();
52
53 ret = tb_nvm_write_buf(nvm, offset, val, bytes);
54 mutex_unlock(&rt->tb->lock);
55
56 return ret;
57}
58
59static int tb_retimer_nvm_add(struct tb_retimer *rt)
60{
61 struct tb_nvm *nvm;
62 u32 val, nvm_size;
63 int ret;
64
65 nvm = tb_nvm_alloc(&rt->dev);
66 if (IS_ERR(nvm))
67 return PTR_ERR(nvm);
68
69 ret = usb4_port_retimer_nvm_read(rt->port, rt->index, NVM_VERSION, &val,
70 sizeof(val));
71 if (ret)
72 goto err_nvm;
73
74 nvm->major = val >> 16;
75 nvm->minor = val >> 8;
76
77 ret = usb4_port_retimer_nvm_read(rt->port, rt->index, NVM_FLASH_SIZE,
78 &val, sizeof(val));
79 if (ret)
80 goto err_nvm;
81
82 nvm_size = (SZ_1M << (val & 7)) / 8;
83 nvm_size = (nvm_size - SZ_16K) / 2;
84
85 ret = tb_nvm_add_active(nvm, nvm_size, tb_retimer_nvm_read);
86 if (ret)
87 goto err_nvm;
88
89 ret = tb_nvm_add_non_active(nvm, NVM_MAX_SIZE, tb_retimer_nvm_write);
90 if (ret)
91 goto err_nvm;
92
93 rt->nvm = nvm;
94 return 0;
95
96err_nvm:
97 tb_nvm_free(nvm);
98 return ret;
99}
100
101static int tb_retimer_nvm_validate_and_write(struct tb_retimer *rt)
102{
103 unsigned int image_size, hdr_size;
104 const u8 *buf = rt->nvm->buf;
105 u16 ds_size, device;
106 int ret;
107
108 image_size = rt->nvm->buf_data_size;
109 if (image_size < NVM_MIN_SIZE || image_size > NVM_MAX_SIZE)
110 return -EINVAL;
111
112 /*
113 * FARB pointer must point inside the image and must at least
114 * contain parts of the digital section we will be reading here.
115 */
116 hdr_size = (*(u32 *)buf) & 0xffffff;
117 if (hdr_size + NVM_DEVID + 2 >= image_size)
118 return -EINVAL;
119
120 /* Digital section start should be aligned to 4k page */
121 if (!IS_ALIGNED(hdr_size, SZ_4K))
122 return -EINVAL;
123
124 /*
125 * Read digital section size and check that it also fits inside
126 * the image.
127 */
128 ds_size = *(u16 *)(buf + hdr_size);
129 if (ds_size >= image_size)
130 return -EINVAL;
131
132 /*
133 * Make sure the device ID in the image matches the retimer
134 * hardware.
135 */
136 device = *(u16 *)(buf + hdr_size + NVM_DEVID);
137 if (device != rt->device)
138 return -EINVAL;
139
140 /* Skip headers in the image */
141 buf += hdr_size;
142 image_size -= hdr_size;
143
144 ret = usb4_port_retimer_nvm_write(rt->port, rt->index, 0, buf,
145 image_size);
146 if (!ret)
147 rt->nvm->flushed = true;
148
149 return ret;
150}
151
152static int tb_retimer_nvm_authenticate(struct tb_retimer *rt, bool auth_only)
153{
154 u32 status;
155 int ret;
156
157 if (auth_only) {
158 ret = usb4_port_retimer_nvm_set_offset(rt->port, rt->index, 0);
159 if (ret)
160 return ret;
161 }
162
163 ret = usb4_port_retimer_nvm_authenticate(rt->port, rt->index);
164 if (ret)
165 return ret;
166
167 usleep_range(100, 150);
168
169 /*
170 * Check the status now if we still can access the retimer. It
171 * is expected that the below fails.
172 */
173 ret = usb4_port_retimer_nvm_authenticate_status(rt->port, rt->index,
174 &status);
175 if (!ret) {
176 rt->auth_status = status;
177 return status ? -EINVAL : 0;
178 }
179
180 return 0;
181}
182
183static ssize_t device_show(struct device *dev, struct device_attribute *attr,
184 char *buf)
185{
186 struct tb_retimer *rt = tb_to_retimer(dev);
187
188 return sprintf(buf, "%#x\n", rt->device);
189}
190static DEVICE_ATTR_RO(device);
191
192static ssize_t nvm_authenticate_show(struct device *dev,
193 struct device_attribute *attr, char *buf)
194{
195 struct tb_retimer *rt = tb_to_retimer(dev);
196 int ret;
197
198 if (!mutex_trylock(&rt->tb->lock))
199 return restart_syscall();
200
201 if (!rt->nvm)
202 ret = -EAGAIN;
203 else
204 ret = sprintf(buf, "%#x\n", rt->auth_status);
205
206 mutex_unlock(&rt->tb->lock);
207
208 return ret;
209}
210
211static ssize_t nvm_authenticate_store(struct device *dev,
212 struct device_attribute *attr, const char *buf, size_t count)
213{
214 struct tb_retimer *rt = tb_to_retimer(dev);
215 int val, ret;
216
217 pm_runtime_get_sync(&rt->dev);
218
219 if (!mutex_trylock(&rt->tb->lock)) {
220 ret = restart_syscall();
221 goto exit_rpm;
222 }
223
224 if (!rt->nvm) {
225 ret = -EAGAIN;
226 goto exit_unlock;
227 }
228
229 ret = kstrtoint(buf, 10, &val);
230 if (ret)
231 goto exit_unlock;
232
233 /* Always clear status */
234 rt->auth_status = 0;
235
236 if (val) {
237 if (val == AUTHENTICATE_ONLY) {
238 ret = tb_retimer_nvm_authenticate(rt, true);
239 } else {
240 if (!rt->nvm->flushed) {
241 if (!rt->nvm->buf) {
242 ret = -EINVAL;
243 goto exit_unlock;
244 }
245
246 ret = tb_retimer_nvm_validate_and_write(rt);
247 if (ret || val == WRITE_ONLY)
248 goto exit_unlock;
249 }
250 if (val == WRITE_AND_AUTHENTICATE)
251 ret = tb_retimer_nvm_authenticate(rt, false);
252 }
253 }
254
255exit_unlock:
256 mutex_unlock(&rt->tb->lock);
257exit_rpm:
258 pm_runtime_mark_last_busy(&rt->dev);
259 pm_runtime_put_autosuspend(&rt->dev);
260
261 if (ret)
262 return ret;
263 return count;
264}
265static DEVICE_ATTR_RW(nvm_authenticate);
266
267static ssize_t nvm_version_show(struct device *dev,
268 struct device_attribute *attr, char *buf)
269{
270 struct tb_retimer *rt = tb_to_retimer(dev);
271 int ret;
272
273 if (!mutex_trylock(&rt->tb->lock))
274 return restart_syscall();
275
276 if (!rt->nvm)
277 ret = -EAGAIN;
278 else
279 ret = sprintf(buf, "%x.%x\n", rt->nvm->major, rt->nvm->minor);
280
281 mutex_unlock(&rt->tb->lock);
282 return ret;
283}
284static DEVICE_ATTR_RO(nvm_version);
285
286static ssize_t vendor_show(struct device *dev, struct device_attribute *attr,
287 char *buf)
288{
289 struct tb_retimer *rt = tb_to_retimer(dev);
290
291 return sprintf(buf, "%#x\n", rt->vendor);
292}
293static DEVICE_ATTR_RO(vendor);
294
295static struct attribute *retimer_attrs[] = {
296 &dev_attr_device.attr,
297 &dev_attr_nvm_authenticate.attr,
298 &dev_attr_nvm_version.attr,
299 &dev_attr_vendor.attr,
300 NULL
301};
302
303static const struct attribute_group retimer_group = {
304 .attrs = retimer_attrs,
305};
306
307static const struct attribute_group *retimer_groups[] = {
308 &retimer_group,
309 NULL
310};
311
312static void tb_retimer_release(struct device *dev)
313{
314 struct tb_retimer *rt = tb_to_retimer(dev);
315
316 kfree(rt);
317}
318
319struct device_type tb_retimer_type = {
320 .name = "thunderbolt_retimer",
321 .groups = retimer_groups,
322 .release = tb_retimer_release,
323};
324
325static int tb_retimer_add(struct tb_port *port, u8 index, u32 auth_status)
326{
327 struct usb4_port *usb4;
328 struct tb_retimer *rt;
329 u32 vendor, device;
330 int ret;
331
332 usb4 = port->usb4;
333 if (!usb4)
334 return -EINVAL;
335
336 ret = usb4_port_retimer_read(port, index, USB4_SB_VENDOR_ID, &vendor,
337 sizeof(vendor));
338 if (ret) {
339 if (ret != -ENODEV)
340 tb_port_warn(port, "failed read retimer VendorId: %d\n", ret);
341 return ret;
342 }
343
344 ret = usb4_port_retimer_read(port, index, USB4_SB_PRODUCT_ID, &device,
345 sizeof(device));
346 if (ret) {
347 if (ret != -ENODEV)
348 tb_port_warn(port, "failed read retimer ProductId: %d\n", ret);
349 return ret;
350 }
351
352 if (vendor != PCI_VENDOR_ID_INTEL && vendor != 0x8087) {
353 tb_port_info(port, "retimer NVM format of vendor %#x is not supported\n",
354 vendor);
355 return -EOPNOTSUPP;
356 }
357
358 /*
359 * Check that it supports NVM operations. If not then don't add
360 * the device at all.
361 */
362 ret = usb4_port_retimer_nvm_sector_size(port, index);
363 if (ret < 0)
364 return ret;
365
366 rt = kzalloc(sizeof(*rt), GFP_KERNEL);
367 if (!rt)
368 return -ENOMEM;
369
370 rt->index = index;
371 rt->vendor = vendor;
372 rt->device = device;
373 rt->auth_status = auth_status;
374 rt->port = port;
375 rt->tb = port->sw->tb;
376
377 rt->dev.parent = &usb4->dev;
378 rt->dev.bus = &tb_bus_type;
379 rt->dev.type = &tb_retimer_type;
380 dev_set_name(&rt->dev, "%s:%u.%u", dev_name(&port->sw->dev),
381 port->port, index);
382
383 ret = device_register(&rt->dev);
384 if (ret) {
385 dev_err(&rt->dev, "failed to register retimer: %d\n", ret);
386 put_device(&rt->dev);
387 return ret;
388 }
389
390 ret = tb_retimer_nvm_add(rt);
391 if (ret) {
392 dev_err(&rt->dev, "failed to add NVM devices: %d\n", ret);
393 device_unregister(&rt->dev);
394 return ret;
395 }
396
397 dev_info(&rt->dev, "new retimer found, vendor=%#x device=%#x\n",
398 rt->vendor, rt->device);
399
400 pm_runtime_no_callbacks(&rt->dev);
401 pm_runtime_set_active(&rt->dev);
402 pm_runtime_enable(&rt->dev);
403 pm_runtime_set_autosuspend_delay(&rt->dev, TB_AUTOSUSPEND_DELAY);
404 pm_runtime_mark_last_busy(&rt->dev);
405 pm_runtime_use_autosuspend(&rt->dev);
406
407 return 0;
408}
409
410static void tb_retimer_remove(struct tb_retimer *rt)
411{
412 dev_info(&rt->dev, "retimer disconnected\n");
413 tb_nvm_free(rt->nvm);
414 device_unregister(&rt->dev);
415}
416
417struct tb_retimer_lookup {
418 const struct tb_port *port;
419 u8 index;
420};
421
422static int retimer_match(struct device *dev, void *data)
423{
424 const struct tb_retimer_lookup *lookup = data;
425 struct tb_retimer *rt = tb_to_retimer(dev);
426
427 return rt && rt->port == lookup->port && rt->index == lookup->index;
428}
429
430static struct tb_retimer *tb_port_find_retimer(struct tb_port *port, u8 index)
431{
432 struct tb_retimer_lookup lookup = { .port = port, .index = index };
433 struct device *dev;
434
435 dev = device_find_child(&port->usb4->dev, &lookup, retimer_match);
436 if (dev)
437 return tb_to_retimer(dev);
438
439 return NULL;
440}
441
442/**
443 * tb_retimer_scan() - Scan for on-board retimers under port
444 * @port: USB4 port to scan
445 * @add: If true also registers found retimers
446 *
447 * Brings the sideband into a state where retimers can be accessed.
448 * Then Tries to enumerate on-board retimers connected to @port. Found
449 * retimers are registered as children of @port if @add is set. Does
450 * not scan for cable retimers for now.
451 */
452int tb_retimer_scan(struct tb_port *port, bool add)
453{
454 u32 status[TB_MAX_RETIMER_INDEX + 1] = {};
455 int ret, i, last_idx = 0;
456
457 /*
458 * Send broadcast RT to make sure retimer indices facing this
459 * port are set.
460 */
461 ret = usb4_port_enumerate_retimers(port);
462 if (ret)
463 return ret;
464
465 /*
466 * Enable sideband channel for each retimer. We can do this
467 * regardless whether there is device connected or not.
468 */
469 for (i = 1; i <= TB_MAX_RETIMER_INDEX; i++)
470 usb4_port_retimer_set_inbound_sbtx(port, i);
471
472 /*
473 * Before doing anything else, read the authentication status.
474 * If the retimer has it set, store it for the new retimer
475 * device instance.
476 */
477 for (i = 1; i <= TB_MAX_RETIMER_INDEX; i++)
478 usb4_port_retimer_nvm_authenticate_status(port, i, &status[i]);
479
480 for (i = 1; i <= TB_MAX_RETIMER_INDEX; i++) {
481 /*
482 * Last retimer is true only for the last on-board
483 * retimer (the one connected directly to the Type-C
484 * port).
485 */
486 ret = usb4_port_retimer_is_last(port, i);
487 if (ret > 0)
488 last_idx = i;
489 else if (ret < 0)
490 break;
491 }
492
493 if (!last_idx)
494 return 0;
495
496 /* Add on-board retimers if they do not exist already */
497 for (i = 1; i <= last_idx; i++) {
498 struct tb_retimer *rt;
499
500 rt = tb_port_find_retimer(port, i);
501 if (rt) {
502 put_device(&rt->dev);
503 } else if (add) {
504 ret = tb_retimer_add(port, i, status[i]);
505 if (ret && ret != -EOPNOTSUPP)
506 break;
507 }
508 }
509
510 return 0;
511}
512
513static int remove_retimer(struct device *dev, void *data)
514{
515 struct tb_retimer *rt = tb_to_retimer(dev);
516 struct tb_port *port = data;
517
518 if (rt && rt->port == port)
519 tb_retimer_remove(rt);
520 return 0;
521}
522
523/**
524 * tb_retimer_remove_all() - Remove all retimers under port
525 * @port: USB4 port whose retimers to remove
526 *
527 * This removes all previously added retimers under @port.
528 */
529void tb_retimer_remove_all(struct tb_port *port)
530{
531 struct usb4_port *usb4;
532
533 usb4 = port->usb4;
534 if (usb4)
535 device_for_each_child_reverse(&usb4->dev, port,
536 remove_retimer);
537}