1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Management-Controller-to-Driver Interface
4 *
5 * Copyright 2008-2013 Solarflare Communications Inc.
6 * Copyright (C) 2022-2023, Advanced Micro Devices, Inc.
7 */
8#include <linux/delay.h>
9#include <linux/slab.h>
10#include <linux/io.h>
11#include <linux/spinlock.h>
12#include <linux/netdevice.h>
13#include <linux/etherdevice.h>
14#include <linux/ethtool.h>
15#include <linux/if_vlan.h>
16#include <linux/timer.h>
17#include <linux/list.h>
18#include <linux/pci.h>
19#include <linux/device.h>
20#include <linux/rwsem.h>
21#include <linux/vmalloc.h>
22#include <net/netevent.h>
23#include <linux/log2.h>
24#include <linux/net_tstamp.h>
25#include <linux/wait.h>
26#include <linux/cdx/bitfield.h>
27
28#include <linux/cdx/mcdi.h>
29#include "mcdid.h"
30
31static void cdx_mcdi_cancel_cmd(struct cdx_mcdi *cdx, struct cdx_mcdi_cmd *cmd);
32static void cdx_mcdi_wait_for_cleanup(struct cdx_mcdi *cdx);
33static int cdx_mcdi_rpc_async_internal(struct cdx_mcdi *cdx,
34 struct cdx_mcdi_cmd *cmd,
35 unsigned int *handle);
36static void cdx_mcdi_start_or_queue(struct cdx_mcdi_iface *mcdi,
37 bool allow_retry);
38static void cdx_mcdi_cmd_start_or_queue(struct cdx_mcdi_iface *mcdi,
39 struct cdx_mcdi_cmd *cmd);
40static bool cdx_mcdi_complete_cmd(struct cdx_mcdi_iface *mcdi,
41 struct cdx_mcdi_cmd *cmd,
42 struct cdx_dword *outbuf,
43 int len,
44 struct list_head *cleanup_list);
45static void cdx_mcdi_timeout_cmd(struct cdx_mcdi_iface *mcdi,
46 struct cdx_mcdi_cmd *cmd,
47 struct list_head *cleanup_list);
48static void cdx_mcdi_cmd_work(struct work_struct *context);
49static void cdx_mcdi_mode_fail(struct cdx_mcdi *cdx, struct list_head *cleanup_list);
50static void _cdx_mcdi_display_error(struct cdx_mcdi *cdx, unsigned int cmd,
51 size_t inlen, int raw, int arg, int err_no);
52
53static bool cdx_cmd_cancelled(struct cdx_mcdi_cmd *cmd)
54{
55 return cmd->state == MCDI_STATE_RUNNING_CANCELLED;
56}
57
58static void cdx_mcdi_cmd_release(struct kref *ref)
59{
60 kfree(container_of(ref, struct cdx_mcdi_cmd, ref));
61}
62
63static unsigned int cdx_mcdi_cmd_handle(struct cdx_mcdi_cmd *cmd)
64{
65 return cmd->handle;
66}
67
68static void _cdx_mcdi_remove_cmd(struct cdx_mcdi_iface *mcdi,
69 struct cdx_mcdi_cmd *cmd,
70 struct list_head *cleanup_list)
71{
72 /* if cancelled, the completers have already been called */
73 if (cdx_cmd_cancelled(cmd))
74 return;
75
76 if (cmd->completer) {
77 list_add_tail(new: &cmd->cleanup_list, head: cleanup_list);
78 ++mcdi->outstanding_cleanups;
79 kref_get(kref: &cmd->ref);
80 }
81}
82
83static void cdx_mcdi_remove_cmd(struct cdx_mcdi_iface *mcdi,
84 struct cdx_mcdi_cmd *cmd,
85 struct list_head *cleanup_list)
86{
87 list_del(entry: &cmd->list);
88 _cdx_mcdi_remove_cmd(mcdi, cmd, cleanup_list);
89 cmd->state = MCDI_STATE_FINISHED;
90 kref_put(kref: &cmd->ref, release: cdx_mcdi_cmd_release);
91 if (list_empty(head: &mcdi->cmd_list))
92 wake_up(&mcdi->cmd_complete_wq);
93}
94
95static unsigned long cdx_mcdi_rpc_timeout(struct cdx_mcdi *cdx, unsigned int cmd)
96{
97 if (!cdx->mcdi_ops->mcdi_rpc_timeout)
98 return MCDI_RPC_TIMEOUT;
99 else
100 return cdx->mcdi_ops->mcdi_rpc_timeout(cdx, cmd);
101}
102
103/**
104 * cdx_mcdi_init - Initialize MCDI (Management Controller Driver Interface) state
105 * @cdx: Handle to the CDX MCDI structure
106 *
107 * This function allocates and initializes internal MCDI structures and resources
108 * for the CDX device, including the workqueue, locking primitives, and command
109 * tracking mechanisms. It sets the initial operating mode and prepares the device
110 * for MCDI operations.
111 *
112 * Return:
113 * * 0 - on success
114 * * -ENOMEM - if memory allocation or workqueue creation fails
115 */
116int cdx_mcdi_init(struct cdx_mcdi *cdx)
117{
118 struct cdx_mcdi_iface *mcdi;
119 int rc = -ENOMEM;
120
121 cdx->mcdi = kzalloc(sizeof(*cdx->mcdi), GFP_KERNEL);
122 if (!cdx->mcdi)
123 goto fail;
124
125 mcdi = cdx_mcdi_if(cdx);
126 mcdi->cdx = cdx;
127
128 mcdi->workqueue = alloc_ordered_workqueue("mcdi_wq", 0);
129 if (!mcdi->workqueue)
130 goto fail2;
131 mutex_init(&mcdi->iface_lock);
132 mcdi->mode = MCDI_MODE_EVENTS;
133 INIT_LIST_HEAD(list: &mcdi->cmd_list);
134 init_waitqueue_head(&mcdi->cmd_complete_wq);
135
136 mcdi->new_epoch = true;
137
138 return 0;
139fail2:
140 kfree(objp: cdx->mcdi);
141 cdx->mcdi = NULL;
142fail:
143 return rc;
144}
145EXPORT_SYMBOL_GPL(cdx_mcdi_init);
146
147/**
148 * cdx_mcdi_finish - Cleanup MCDI (Management Controller Driver Interface) state
149 * @cdx: Handle to the CDX MCDI structure
150 *
151 * This function is responsible for cleaning up the MCDI (Management Controller Driver Interface)
152 * resources associated with a cdx_mcdi structure. Also destroys the mcdi workqueue.
153 *
154 */
155void cdx_mcdi_finish(struct cdx_mcdi *cdx)
156{
157 struct cdx_mcdi_iface *mcdi;
158
159 mcdi = cdx_mcdi_if(cdx);
160 if (!mcdi)
161 return;
162
163 cdx_mcdi_wait_for_cleanup(cdx);
164
165 destroy_workqueue(wq: mcdi->workqueue);
166 kfree(objp: cdx->mcdi);
167 cdx->mcdi = NULL;
168}
169EXPORT_SYMBOL_GPL(cdx_mcdi_finish);
170
171static bool cdx_mcdi_flushed(struct cdx_mcdi_iface *mcdi, bool ignore_cleanups)
172{
173 bool flushed;
174
175 mutex_lock(&mcdi->iface_lock);
176 flushed = list_empty(head: &mcdi->cmd_list) &&
177 (ignore_cleanups || !mcdi->outstanding_cleanups);
178 mutex_unlock(lock: &mcdi->iface_lock);
179 return flushed;
180}
181
182/* Wait for outstanding MCDI commands to complete. */
183static void cdx_mcdi_wait_for_cleanup(struct cdx_mcdi *cdx)
184{
185 struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);
186
187 if (!mcdi)
188 return;
189
190 wait_event(mcdi->cmd_complete_wq,
191 cdx_mcdi_flushed(mcdi, false));
192}
193
194int cdx_mcdi_wait_for_quiescence(struct cdx_mcdi *cdx,
195 unsigned int timeout_jiffies)
196{
197 struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);
198 DEFINE_WAIT_FUNC(wait, woken_wake_function);
199 int rc = 0;
200
201 if (!mcdi)
202 return -EINVAL;
203
204 flush_workqueue(mcdi->workqueue);
205
206 add_wait_queue(wq_head: &mcdi->cmd_complete_wq, wq_entry: &wait);
207
208 while (!cdx_mcdi_flushed(mcdi, ignore_cleanups: true)) {
209 rc = wait_woken(wq_entry: &wait, TASK_IDLE, timeout: timeout_jiffies);
210 if (rc)
211 continue;
212 break;
213 }
214
215 remove_wait_queue(wq_head: &mcdi->cmd_complete_wq, wq_entry: &wait);
216
217 if (rc > 0)
218 rc = 0;
219 else if (rc == 0)
220 rc = -ETIMEDOUT;
221
222 return rc;
223}
224
225static u8 cdx_mcdi_payload_csum(const struct cdx_dword *hdr, size_t hdr_len,
226 const struct cdx_dword *sdu, size_t sdu_len)
227{
228 u8 *p = (u8 *)hdr;
229 u8 csum = 0;
230 int i;
231
232 for (i = 0; i < hdr_len; i++)
233 csum += p[i];
234
235 p = (u8 *)sdu;
236 for (i = 0; i < sdu_len; i++)
237 csum += p[i];
238
239 return ~csum & 0xff;
240}
241
242static void cdx_mcdi_send_request(struct cdx_mcdi *cdx,
243 struct cdx_mcdi_cmd *cmd)
244{
245 struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);
246 const struct cdx_dword *inbuf = cmd->inbuf;
247 size_t inlen = cmd->inlen;
248 struct cdx_dword hdr[2];
249 size_t hdr_len;
250 bool not_epoch;
251 u32 xflags;
252
253 if (!mcdi)
254 return;
255
256 mcdi->prev_seq = cmd->seq;
257 mcdi->seq_held_by[cmd->seq] = cmd;
258 mcdi->db_held_by = cmd;
259 cmd->started = jiffies;
260
261 not_epoch = !mcdi->new_epoch;
262 xflags = 0;
263
264 /* MCDI v2 */
265 WARN_ON(inlen > MCDI_CTL_SDU_LEN_MAX_V2);
266 CDX_POPULATE_DWORD_7(hdr[0],
267 MCDI_HEADER_RESPONSE, 0,
268 MCDI_HEADER_RESYNC, 1,
269 MCDI_HEADER_CODE, MC_CMD_V2_EXTN,
270 MCDI_HEADER_DATALEN, 0,
271 MCDI_HEADER_SEQ, cmd->seq,
272 MCDI_HEADER_XFLAGS, xflags,
273 MCDI_HEADER_NOT_EPOCH, not_epoch);
274 CDX_POPULATE_DWORD_3(hdr[1],
275 MC_CMD_V2_EXTN_IN_EXTENDED_CMD, cmd->cmd,
276 MC_CMD_V2_EXTN_IN_ACTUAL_LEN, inlen,
277 MC_CMD_V2_EXTN_IN_MESSAGE_TYPE,
278 MC_CMD_V2_EXTN_IN_MCDI_MESSAGE_TYPE_PLATFORM);
279 hdr_len = 8;
280
281 hdr[0].cdx_u32 |= (__force __le32)(cdx_mcdi_payload_csum(hdr, hdr_len, sdu: inbuf, sdu_len: inlen) <<
282 MCDI_HEADER_XFLAGS_LBN);
283
284 print_hex_dump_debug("MCDI REQ HEADER: ", DUMP_PREFIX_NONE, 32, 4, hdr, hdr_len, false);
285 print_hex_dump_debug("MCDI REQ PAYLOAD: ", DUMP_PREFIX_NONE, 32, 4, inbuf, inlen, false);
286
287 cdx->mcdi_ops->mcdi_request(cdx, hdr, hdr_len, inbuf, inlen);
288
289 mcdi->new_epoch = false;
290}
291
292static int cdx_mcdi_errno(struct cdx_mcdi *cdx, unsigned int mcdi_err)
293{
294 switch (mcdi_err) {
295 case 0:
296 case MC_CMD_ERR_QUEUE_FULL:
297 return mcdi_err;
298 case MC_CMD_ERR_EPERM:
299 return -EPERM;
300 case MC_CMD_ERR_ENOENT:
301 return -ENOENT;
302 case MC_CMD_ERR_EINTR:
303 return -EINTR;
304 case MC_CMD_ERR_EAGAIN:
305 return -EAGAIN;
306 case MC_CMD_ERR_EACCES:
307 return -EACCES;
308 case MC_CMD_ERR_EBUSY:
309 return -EBUSY;
310 case MC_CMD_ERR_EINVAL:
311 return -EINVAL;
312 case MC_CMD_ERR_ERANGE:
313 return -ERANGE;
314 case MC_CMD_ERR_EDEADLK:
315 return -EDEADLK;
316 case MC_CMD_ERR_ENOSYS:
317 return -EOPNOTSUPP;
318 case MC_CMD_ERR_ETIME:
319 return -ETIME;
320 case MC_CMD_ERR_EALREADY:
321 return -EALREADY;
322 case MC_CMD_ERR_ENOSPC:
323 return -ENOSPC;
324 case MC_CMD_ERR_ENOMEM:
325 return -ENOMEM;
326 case MC_CMD_ERR_ENOTSUP:
327 return -EOPNOTSUPP;
328 case MC_CMD_ERR_ALLOC_FAIL:
329 return -ENOBUFS;
330 case MC_CMD_ERR_MAC_EXIST:
331 return -EADDRINUSE;
332 case MC_CMD_ERR_NO_EVB_PORT:
333 return -EAGAIN;
334 default:
335 return -EPROTO;
336 }
337}
338
339static void cdx_mcdi_process_cleanup_list(struct cdx_mcdi *cdx,
340 struct list_head *cleanup_list)
341{
342 struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);
343 unsigned int cleanups = 0;
344
345 if (!mcdi)
346 return;
347
348 while (!list_empty(head: cleanup_list)) {
349 struct cdx_mcdi_cmd *cmd =
350 list_first_entry(cleanup_list,
351 struct cdx_mcdi_cmd, cleanup_list);
352 cmd->completer(cdx, cmd->cookie, cmd->rc,
353 cmd->outbuf, cmd->outlen);
354 list_del(entry: &cmd->cleanup_list);
355 kref_put(kref: &cmd->ref, release: cdx_mcdi_cmd_release);
356 ++cleanups;
357 }
358
359 if (cleanups) {
360 bool all_done;
361
362 mutex_lock(&mcdi->iface_lock);
363 CDX_WARN_ON_PARANOID(cleanups > mcdi->outstanding_cleanups);
364 all_done = (mcdi->outstanding_cleanups -= cleanups) == 0;
365 mutex_unlock(lock: &mcdi->iface_lock);
366 if (all_done)
367 wake_up(&mcdi->cmd_complete_wq);
368 }
369}
370
371static void _cdx_mcdi_cancel_cmd(struct cdx_mcdi_iface *mcdi,
372 unsigned int handle,
373 struct list_head *cleanup_list)
374{
375 struct cdx_mcdi_cmd *cmd;
376
377 list_for_each_entry(cmd, &mcdi->cmd_list, list)
378 if (cdx_mcdi_cmd_handle(cmd) == handle) {
379 switch (cmd->state) {
380 case MCDI_STATE_QUEUED:
381 case MCDI_STATE_RETRY:
382 pr_debug("command %#x inlen %zu cancelled in queue\n",
383 cmd->cmd, cmd->inlen);
384 /* if not yet running, properly cancel it */
385 cmd->rc = -EPIPE;
386 cdx_mcdi_remove_cmd(mcdi, cmd, cleanup_list);
387 break;
388 case MCDI_STATE_RUNNING:
389 case MCDI_STATE_RUNNING_CANCELLED:
390 case MCDI_STATE_FINISHED:
391 default:
392 /* invalid state? */
393 WARN_ON(1);
394 }
395 break;
396 }
397}
398
399static void cdx_mcdi_cancel_cmd(struct cdx_mcdi *cdx, struct cdx_mcdi_cmd *cmd)
400{
401 struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);
402 LIST_HEAD(cleanup_list);
403
404 if (!mcdi)
405 return;
406
407 mutex_lock(&mcdi->iface_lock);
408 cdx_mcdi_timeout_cmd(mcdi, cmd, cleanup_list: &cleanup_list);
409 mutex_unlock(lock: &mcdi->iface_lock);
410 cdx_mcdi_process_cleanup_list(cdx, cleanup_list: &cleanup_list);
411}
412
413struct cdx_mcdi_blocking_data {
414 struct kref ref;
415 bool done;
416 wait_queue_head_t wq;
417 int rc;
418 struct cdx_dword *outbuf;
419 size_t outlen;
420 size_t outlen_actual;
421};
422
423static void cdx_mcdi_blocking_data_release(struct kref *ref)
424{
425 kfree(container_of(ref, struct cdx_mcdi_blocking_data, ref));
426}
427
428static void cdx_mcdi_rpc_completer(struct cdx_mcdi *cdx, unsigned long cookie,
429 int rc, struct cdx_dword *outbuf,
430 size_t outlen_actual)
431{
432 struct cdx_mcdi_blocking_data *wait_data =
433 (struct cdx_mcdi_blocking_data *)cookie;
434
435 wait_data->rc = rc;
436 memcpy(wait_data->outbuf, outbuf,
437 min(outlen_actual, wait_data->outlen));
438 wait_data->outlen_actual = outlen_actual;
439 /* memory barrier */
440 smp_wmb();
441 wait_data->done = true;
442 wake_up(&wait_data->wq);
443 kref_put(kref: &wait_data->ref, release: cdx_mcdi_blocking_data_release);
444}
445
446static int cdx_mcdi_rpc_sync(struct cdx_mcdi *cdx, unsigned int cmd,
447 const struct cdx_dword *inbuf, size_t inlen,
448 struct cdx_dword *outbuf, size_t outlen,
449 size_t *outlen_actual, bool quiet)
450{
451 struct cdx_mcdi_blocking_data *wait_data;
452 struct cdx_mcdi_cmd *cmd_item;
453 unsigned int handle;
454 int rc;
455
456 if (outlen_actual)
457 *outlen_actual = 0;
458
459 wait_data = kmalloc(sizeof(*wait_data), GFP_KERNEL);
460 if (!wait_data)
461 return -ENOMEM;
462
463 cmd_item = kmalloc(sizeof(*cmd_item), GFP_KERNEL);
464 if (!cmd_item) {
465 kfree(objp: wait_data);
466 return -ENOMEM;
467 }
468
469 kref_init(kref: &wait_data->ref);
470 wait_data->done = false;
471 init_waitqueue_head(&wait_data->wq);
472 wait_data->outbuf = outbuf;
473 wait_data->outlen = outlen;
474
475 kref_init(kref: &cmd_item->ref);
476 cmd_item->quiet = quiet;
477 cmd_item->cookie = (unsigned long)wait_data;
478 cmd_item->completer = &cdx_mcdi_rpc_completer;
479 cmd_item->cmd = cmd;
480 cmd_item->inlen = inlen;
481 cmd_item->inbuf = inbuf;
482
483 /* Claim an extra reference for the completer to put. */
484 kref_get(kref: &wait_data->ref);
485 rc = cdx_mcdi_rpc_async_internal(cdx, cmd: cmd_item, handle: &handle);
486 if (rc) {
487 kref_put(kref: &wait_data->ref, release: cdx_mcdi_blocking_data_release);
488 goto out;
489 }
490
491 if (!wait_event_timeout(wait_data->wq, wait_data->done,
492 cdx_mcdi_rpc_timeout(cdx, cmd)) &&
493 !wait_data->done) {
494 pr_err("MC command 0x%x inlen %zu timed out (sync)\n",
495 cmd, inlen);
496
497 cdx_mcdi_cancel_cmd(cdx, cmd: cmd_item);
498
499 wait_data->rc = -ETIMEDOUT;
500 wait_data->outlen_actual = 0;
501 }
502
503 if (outlen_actual)
504 *outlen_actual = wait_data->outlen_actual;
505 rc = wait_data->rc;
506
507out:
508 kref_put(kref: &wait_data->ref, release: cdx_mcdi_blocking_data_release);
509
510 return rc;
511}
512
513static bool cdx_mcdi_get_seq(struct cdx_mcdi_iface *mcdi, unsigned char *seq)
514{
515 *seq = mcdi->prev_seq;
516 do {
517 *seq = (*seq + 1) % ARRAY_SIZE(mcdi->seq_held_by);
518 } while (mcdi->seq_held_by[*seq] && *seq != mcdi->prev_seq);
519 return !mcdi->seq_held_by[*seq];
520}
521
522static int cdx_mcdi_rpc_async_internal(struct cdx_mcdi *cdx,
523 struct cdx_mcdi_cmd *cmd,
524 unsigned int *handle)
525{
526 struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);
527 LIST_HEAD(cleanup_list);
528
529 if (!mcdi) {
530 kref_put(kref: &cmd->ref, release: cdx_mcdi_cmd_release);
531 return -ENETDOWN;
532 }
533
534 if (mcdi->mode == MCDI_MODE_FAIL) {
535 kref_put(kref: &cmd->ref, release: cdx_mcdi_cmd_release);
536 return -ENETDOWN;
537 }
538
539 cmd->mcdi = mcdi;
540 INIT_WORK(&cmd->work, cdx_mcdi_cmd_work);
541 INIT_LIST_HEAD(list: &cmd->list);
542 INIT_LIST_HEAD(list: &cmd->cleanup_list);
543 cmd->rc = 0;
544 cmd->outbuf = NULL;
545 cmd->outlen = 0;
546
547 queue_work(wq: mcdi->workqueue, work: &cmd->work);
548 return 0;
549}
550
551static void cdx_mcdi_cmd_start_or_queue(struct cdx_mcdi_iface *mcdi,
552 struct cdx_mcdi_cmd *cmd)
553{
554 struct cdx_mcdi *cdx = mcdi->cdx;
555 u8 seq;
556
557 if (!mcdi->db_held_by &&
558 cdx_mcdi_get_seq(mcdi, seq: &seq)) {
559 cmd->seq = seq;
560 cmd->reboot_seen = false;
561 cdx_mcdi_send_request(cdx, cmd);
562 cmd->state = MCDI_STATE_RUNNING;
563 } else {
564 cmd->state = MCDI_STATE_QUEUED;
565 }
566}
567
568/* try to advance other commands */
569static void cdx_mcdi_start_or_queue(struct cdx_mcdi_iface *mcdi,
570 bool allow_retry)
571{
572 struct cdx_mcdi_cmd *cmd, *tmp;
573
574 list_for_each_entry_safe(cmd, tmp, &mcdi->cmd_list, list)
575 if (cmd->state == MCDI_STATE_QUEUED ||
576 (cmd->state == MCDI_STATE_RETRY && allow_retry))
577 cdx_mcdi_cmd_start_or_queue(mcdi, cmd);
578}
579
580/**
581 * cdx_mcdi_process_cmd - Process an incoming MCDI response
582 * @cdx: Handle to the CDX MCDI structure
583 * @outbuf: Pointer to the response buffer received from the management controller
584 * @len: Length of the response buffer in bytes
585 *
586 * This function handles a response from the management controller. It locates the
587 * corresponding command using the sequence number embedded in the header,
588 * completes the command if it is still pending, and initiates any necessary cleanup.
589 *
590 * The function assumes that the response buffer is well-formed and at least one
591 * dword in size.
592 */
593void cdx_mcdi_process_cmd(struct cdx_mcdi *cdx, struct cdx_dword *outbuf, int len)
594{
595 struct cdx_mcdi_iface *mcdi;
596 struct cdx_mcdi_cmd *cmd;
597 LIST_HEAD(cleanup_list);
598 unsigned int respseq;
599
600 if (!len || !outbuf) {
601 pr_err("Got empty MC response\n");
602 return;
603 }
604
605 mcdi = cdx_mcdi_if(cdx);
606 if (!mcdi)
607 return;
608
609 respseq = CDX_DWORD_FIELD(outbuf[0], MCDI_HEADER_SEQ);
610
611 mutex_lock(&mcdi->iface_lock);
612 cmd = mcdi->seq_held_by[respseq];
613
614 if (cmd) {
615 if (cmd->state == MCDI_STATE_FINISHED) {
616 mutex_unlock(lock: &mcdi->iface_lock);
617 kref_put(kref: &cmd->ref, release: cdx_mcdi_cmd_release);
618 return;
619 }
620
621 cdx_mcdi_complete_cmd(mcdi, cmd, outbuf, len, cleanup_list: &cleanup_list);
622 } else {
623 pr_err("MC response unexpected for seq : %0X\n", respseq);
624 }
625
626 mutex_unlock(lock: &mcdi->iface_lock);
627
628 cdx_mcdi_process_cleanup_list(cdx: mcdi->cdx, cleanup_list: &cleanup_list);
629}
630EXPORT_SYMBOL_GPL(cdx_mcdi_process_cmd);
631
632static void cdx_mcdi_cmd_work(struct work_struct *context)
633{
634 struct cdx_mcdi_cmd *cmd =
635 container_of(context, struct cdx_mcdi_cmd, work);
636 struct cdx_mcdi_iface *mcdi = cmd->mcdi;
637
638 mutex_lock(&mcdi->iface_lock);
639
640 cmd->handle = mcdi->prev_handle++;
641 list_add_tail(new: &cmd->list, head: &mcdi->cmd_list);
642 cdx_mcdi_cmd_start_or_queue(mcdi, cmd);
643
644 mutex_unlock(lock: &mcdi->iface_lock);
645}
646
647/*
648 * Returns true if the MCDI module is finished with the command.
649 * (examples of false would be if the command was proxied, or it was
650 * rejected by the MC due to lack of resources and requeued).
651 */
652static bool cdx_mcdi_complete_cmd(struct cdx_mcdi_iface *mcdi,
653 struct cdx_mcdi_cmd *cmd,
654 struct cdx_dword *outbuf,
655 int len,
656 struct list_head *cleanup_list)
657{
658 size_t resp_hdr_len, resp_data_len;
659 struct cdx_mcdi *cdx = mcdi->cdx;
660 unsigned int respcmd, error;
661 bool completed = false;
662 int rc;
663
664 /* ensure the command can't go away before this function returns */
665 kref_get(kref: &cmd->ref);
666
667 respcmd = CDX_DWORD_FIELD(outbuf[0], MCDI_HEADER_CODE);
668 error = CDX_DWORD_FIELD(outbuf[0], MCDI_HEADER_ERROR);
669
670 if (respcmd != MC_CMD_V2_EXTN) {
671 resp_hdr_len = 4;
672 resp_data_len = CDX_DWORD_FIELD(outbuf[0], MCDI_HEADER_DATALEN);
673 } else {
674 resp_data_len = 0;
675 resp_hdr_len = 8;
676 if (len >= 8)
677 resp_data_len =
678 CDX_DWORD_FIELD(outbuf[1], MC_CMD_V2_EXTN_IN_ACTUAL_LEN);
679 }
680
681 if ((resp_hdr_len + resp_data_len) > len) {
682 pr_warn("Incomplete MCDI response received %d. Expected %zu\n",
683 len, (resp_hdr_len + resp_data_len));
684 resp_data_len = 0;
685 }
686
687 print_hex_dump_debug("MCDI RESP HEADER: ", DUMP_PREFIX_NONE, 32, 4,
688 outbuf, resp_hdr_len, false);
689 print_hex_dump_debug("MCDI RESP PAYLOAD: ", DUMP_PREFIX_NONE, 32, 4,
690 outbuf + (resp_hdr_len / 4), resp_data_len, false);
691
692 if (error && resp_data_len == 0) {
693 /* MC rebooted during command */
694 rc = -EIO;
695 } else {
696 if (WARN_ON_ONCE(error && resp_data_len < 4))
697 resp_data_len = 4;
698 if (error) {
699 rc = CDX_DWORD_FIELD(outbuf[resp_hdr_len / 4], CDX_DWORD);
700 if (!cmd->quiet) {
701 int err_arg = 0;
702
703 if (resp_data_len >= MC_CMD_ERR_ARG_OFST + 4) {
704 int offset = (resp_hdr_len + MC_CMD_ERR_ARG_OFST) / 4;
705
706 err_arg = CDX_DWORD_VAL(outbuf[offset]);
707 }
708
709 _cdx_mcdi_display_error(cdx, cmd: cmd->cmd,
710 inlen: cmd->inlen, raw: rc, arg: err_arg,
711 err_no: cdx_mcdi_errno(cdx, mcdi_err: rc));
712 }
713 rc = cdx_mcdi_errno(cdx, mcdi_err: rc);
714 } else {
715 rc = 0;
716 }
717 }
718
719 /* free doorbell */
720 if (mcdi->db_held_by == cmd)
721 mcdi->db_held_by = NULL;
722
723 if (cdx_cmd_cancelled(cmd)) {
724 list_del(entry: &cmd->list);
725 kref_put(kref: &cmd->ref, release: cdx_mcdi_cmd_release);
726 completed = true;
727 } else if (rc == MC_CMD_ERR_QUEUE_FULL) {
728 cmd->state = MCDI_STATE_RETRY;
729 } else {
730 cmd->rc = rc;
731 cmd->outbuf = outbuf + DIV_ROUND_UP(resp_hdr_len, 4);
732 cmd->outlen = resp_data_len;
733 cdx_mcdi_remove_cmd(mcdi, cmd, cleanup_list);
734 completed = true;
735 }
736
737 /* free sequence number and buffer */
738 mcdi->seq_held_by[cmd->seq] = NULL;
739
740 cdx_mcdi_start_or_queue(mcdi, allow_retry: rc != MC_CMD_ERR_QUEUE_FULL);
741
742 /* wake up anyone waiting for flush */
743 wake_up(&mcdi->cmd_complete_wq);
744
745 kref_put(kref: &cmd->ref, release: cdx_mcdi_cmd_release);
746
747 return completed;
748}
749
750static void cdx_mcdi_timeout_cmd(struct cdx_mcdi_iface *mcdi,
751 struct cdx_mcdi_cmd *cmd,
752 struct list_head *cleanup_list)
753{
754 struct cdx_mcdi *cdx = mcdi->cdx;
755
756 pr_err("MC command 0x%x inlen %zu state %d timed out after %u ms\n",
757 cmd->cmd, cmd->inlen, cmd->state,
758 jiffies_to_msecs(jiffies - cmd->started));
759
760 cmd->rc = -ETIMEDOUT;
761 cdx_mcdi_remove_cmd(mcdi, cmd, cleanup_list);
762
763 cdx_mcdi_mode_fail(cdx, cleanup_list);
764}
765
766/**
767 * cdx_mcdi_rpc - Issue an MCDI command and wait for completion
768 * @cdx: NIC through which to issue the command
769 * @cmd: Command type number
770 * @inbuf: Command parameters
771 * @inlen: Length of command parameters, in bytes. Must be a multiple
772 * of 4 and no greater than %MCDI_CTL_SDU_LEN_MAX_V1.
773 * @outbuf: Response buffer. May be %NULL if @outlen is 0.
774 * @outlen: Length of response buffer, in bytes. If the actual
775 * response is longer than @outlen & ~3, it will be truncated
776 * to that length.
777 * @outlen_actual: Pointer through which to return the actual response
778 * length. May be %NULL if this is not needed.
779 *
780 * This function may sleep and therefore must be called in process
781 * context.
782 *
783 * Return: A negative error code, or zero if successful. The error
784 * code may come from the MCDI response or may indicate a failure
785 * to communicate with the MC. In the former case, the response
786 * will still be copied to @outbuf and *@outlen_actual will be
787 * set accordingly. In the latter case, *@outlen_actual will be
788 * set to zero.
789 */
790int cdx_mcdi_rpc(struct cdx_mcdi *cdx, unsigned int cmd,
791 const struct cdx_dword *inbuf, size_t inlen,
792 struct cdx_dword *outbuf, size_t outlen,
793 size_t *outlen_actual)
794{
795 return cdx_mcdi_rpc_sync(cdx, cmd, inbuf, inlen, outbuf, outlen,
796 outlen_actual, quiet: false);
797}
798EXPORT_SYMBOL_GPL(cdx_mcdi_rpc);
799
800/**
801 * cdx_mcdi_rpc_async - Schedule an MCDI command to run asynchronously
802 * @cdx: NIC through which to issue the command
803 * @cmd: Command type number
804 * @inbuf: Command parameters
805 * @inlen: Length of command parameters, in bytes
806 * @complete: Function to be called on completion or cancellation.
807 * @cookie: Arbitrary value to be passed to @complete.
808 *
809 * This function does not sleep and therefore may be called in atomic
810 * context. It will fail if event queues are disabled or if MCDI
811 * event completions have been disabled due to an error.
812 *
813 * If it succeeds, the @complete function will be called exactly once
814 * in process context, when one of the following occurs:
815 * (a) the completion event is received (in process context)
816 * (b) event queues are disabled (in the process that disables them)
817 */
818int
819cdx_mcdi_rpc_async(struct cdx_mcdi *cdx, unsigned int cmd,
820 const struct cdx_dword *inbuf, size_t inlen,
821 cdx_mcdi_async_completer *complete, unsigned long cookie)
822{
823 struct cdx_mcdi_cmd *cmd_item =
824 kmalloc(sizeof(struct cdx_mcdi_cmd) + inlen, GFP_ATOMIC);
825
826 if (!cmd_item)
827 return -ENOMEM;
828
829 kref_init(kref: &cmd_item->ref);
830 cmd_item->quiet = true;
831 cmd_item->cookie = cookie;
832 cmd_item->completer = complete;
833 cmd_item->cmd = cmd;
834 cmd_item->inlen = inlen;
835 /* inbuf is probably not valid after return, so take a copy */
836 cmd_item->inbuf = (struct cdx_dword *)(cmd_item + 1);
837 memcpy(cmd_item + 1, inbuf, inlen);
838
839 return cdx_mcdi_rpc_async_internal(cdx, cmd: cmd_item, NULL);
840}
841
842static void _cdx_mcdi_display_error(struct cdx_mcdi *cdx, unsigned int cmd,
843 size_t inlen, int raw, int arg, int err_no)
844{
845 pr_err("MC command 0x%x inlen %d failed err_no=%d (raw=%d) arg=%d\n",
846 cmd, (int)inlen, err_no, raw, arg);
847}
848
849/*
850 * Set MCDI mode to fail to prevent any new commands, then cancel any
851 * outstanding commands.
852 * Caller must hold the mcdi iface_lock.
853 */
854static void cdx_mcdi_mode_fail(struct cdx_mcdi *cdx, struct list_head *cleanup_list)
855{
856 struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);
857
858 if (!mcdi)
859 return;
860
861 mcdi->mode = MCDI_MODE_FAIL;
862
863 while (!list_empty(head: &mcdi->cmd_list)) {
864 struct cdx_mcdi_cmd *cmd;
865
866 cmd = list_first_entry(&mcdi->cmd_list, struct cdx_mcdi_cmd,
867 list);
868 _cdx_mcdi_cancel_cmd(mcdi, handle: cdx_mcdi_cmd_handle(cmd), cleanup_list);
869 }
870}
871

source code of linux/drivers/cdx/controller/mcdi.c