1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * libata-pmp.c - libata port multiplier support
4 *
5 * Copyright (c) 2007 SUSE Linux Products GmbH
6 * Copyright (c) 2007 Tejun Heo <teheo@suse.de>
7 */
8
9#include <linux/kernel.h>
10#include <linux/export.h>
11#include <linux/libata.h>
12#include <linux/slab.h>
13#include "libata.h"
14#include "libata-transport.h"
15
16const struct ata_port_operations sata_pmp_port_ops = {
17 .inherits = &sata_port_ops,
18 .pmp_prereset = ata_std_prereset,
19 .pmp_hardreset = sata_std_hardreset,
20 .pmp_postreset = ata_std_postreset,
21 .error_handler = sata_pmp_error_handler,
22};
23
24/**
25 * sata_pmp_read - read PMP register
26 * @link: link to read PMP register for
27 * @reg: register to read
28 * @r_val: resulting value
29 *
30 * Read PMP register.
31 *
32 * LOCKING:
33 * Kernel thread context (may sleep).
34 *
35 * RETURNS:
36 * 0 on success, AC_ERR_* mask on failure.
37 */
38static unsigned int sata_pmp_read(struct ata_link *link, int reg, u32 *r_val)
39{
40 struct ata_port *ap = link->ap;
41 struct ata_device *pmp_dev = ap->link.device;
42 struct ata_taskfile tf;
43 unsigned int err_mask;
44
45 ata_tf_init(dev: pmp_dev, tf: &tf);
46 tf.command = ATA_CMD_PMP_READ;
47 tf.protocol = ATA_PROT_NODATA;
48 tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_LBA48;
49 tf.feature = reg;
50 tf.device = link->pmp;
51
52 err_mask = ata_exec_internal(dev: pmp_dev, tf: &tf, NULL, dma_dir: DMA_NONE, NULL, buflen: 0,
53 timeout: SATA_PMP_RW_TIMEOUT);
54 if (err_mask)
55 return err_mask;
56
57 *r_val = tf.nsect | tf.lbal << 8 | tf.lbam << 16 | tf.lbah << 24;
58 return 0;
59}
60
61/**
62 * sata_pmp_write - write PMP register
63 * @link: link to write PMP register for
64 * @reg: register to write
65 * @val: value to write
66 *
67 * Write PMP register.
68 *
69 * LOCKING:
70 * Kernel thread context (may sleep).
71 *
72 * RETURNS:
73 * 0 on success, AC_ERR_* mask on failure.
74 */
75static unsigned int sata_pmp_write(struct ata_link *link, int reg, u32 val)
76{
77 struct ata_port *ap = link->ap;
78 struct ata_device *pmp_dev = ap->link.device;
79 struct ata_taskfile tf;
80
81 ata_tf_init(dev: pmp_dev, tf: &tf);
82 tf.command = ATA_CMD_PMP_WRITE;
83 tf.protocol = ATA_PROT_NODATA;
84 tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_LBA48;
85 tf.feature = reg;
86 tf.device = link->pmp;
87 tf.nsect = val & 0xff;
88 tf.lbal = (val >> 8) & 0xff;
89 tf.lbam = (val >> 16) & 0xff;
90 tf.lbah = (val >> 24) & 0xff;
91
92 return ata_exec_internal(dev: pmp_dev, tf: &tf, NULL, dma_dir: DMA_NONE, NULL, buflen: 0,
93 timeout: SATA_PMP_RW_TIMEOUT);
94}
95
96/**
97 * sata_pmp_qc_defer_cmd_switch - qc_defer for command switching PMP
98 * @qc: ATA command in question
99 *
100 * A host which has command switching PMP support cannot issue
101 * commands to multiple links simultaneously.
102 *
103 * LOCKING:
104 * spin_lock_irqsave(host lock)
105 *
106 * RETURNS:
107 * ATA_DEFER_* if deferring is needed, 0 otherwise.
108 */
109int sata_pmp_qc_defer_cmd_switch(struct ata_queued_cmd *qc)
110{
111 struct ata_link *link = qc->dev->link;
112 struct ata_port *ap = link->ap;
113
114 if (ap->excl_link == NULL || ap->excl_link == link) {
115 if (ap->nr_active_links == 0 || ata_link_active(link)) {
116 qc->flags |= ATA_QCFLAG_CLEAR_EXCL;
117 return ata_std_qc_defer(qc);
118 }
119
120 ap->excl_link = link;
121 }
122
123 return ATA_DEFER_PORT;
124}
125
126/**
127 * sata_pmp_scr_read - read PSCR
128 * @link: ATA link to read PSCR for
129 * @reg: PSCR to read
130 * @r_val: resulting value
131 *
132 * Read PSCR @reg into @r_val for @link, to be called from
133 * ata_scr_read().
134 *
135 * LOCKING:
136 * Kernel thread context (may sleep).
137 *
138 * RETURNS:
139 * 0 on success, -errno on failure.
140 */
141int sata_pmp_scr_read(struct ata_link *link, int reg, u32 *r_val)
142{
143 unsigned int err_mask;
144
145 if (reg > SATA_PMP_PSCR_CONTROL)
146 return -EINVAL;
147
148 err_mask = sata_pmp_read(link, reg, r_val);
149 if (err_mask) {
150 ata_link_warn(link, "failed to read SCR %d (Emask=0x%x)\n",
151 reg, err_mask);
152 return -EIO;
153 }
154 return 0;
155}
156
157/**
158 * sata_pmp_scr_write - write PSCR
159 * @link: ATA link to write PSCR for
160 * @reg: PSCR to write
161 * @val: value to be written
162 *
163 * Write @val to PSCR @reg for @link, to be called from
164 * ata_scr_write() and ata_scr_write_flush().
165 *
166 * LOCKING:
167 * Kernel thread context (may sleep).
168 *
169 * RETURNS:
170 * 0 on success, -errno on failure.
171 */
172int sata_pmp_scr_write(struct ata_link *link, int reg, u32 val)
173{
174 unsigned int err_mask;
175
176 if (reg > SATA_PMP_PSCR_CONTROL)
177 return -EINVAL;
178
179 err_mask = sata_pmp_write(link, reg, val);
180 if (err_mask) {
181 ata_link_warn(link, "failed to write SCR %d (Emask=0x%x)\n",
182 reg, err_mask);
183 return -EIO;
184 }
185 return 0;
186}
187
188/**
189 * sata_pmp_set_lpm - configure LPM for a PMP link
190 * @link: PMP link to configure LPM for
191 * @policy: target LPM policy
192 * @hints: LPM hints
193 *
194 * Configure LPM for @link. This function will contain any PMP
195 * specific workarounds if necessary.
196 *
197 * LOCKING:
198 * EH context.
199 *
200 * RETURNS:
201 * 0 on success, -errno on failure.
202 */
203int sata_pmp_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
204 unsigned hints)
205{
206 return sata_link_scr_lpm(link, policy, spm_wakeup: true);
207}
208
209/**
210 * sata_pmp_read_gscr - read GSCR block of SATA PMP
211 * @dev: PMP device
212 * @gscr: buffer to read GSCR block into
213 *
214 * Read selected PMP GSCRs from the PMP at @dev. This will serve
215 * as configuration and identification info for the PMP.
216 *
217 * LOCKING:
218 * Kernel thread context (may sleep).
219 *
220 * RETURNS:
221 * 0 on success, -errno on failure.
222 */
223static int sata_pmp_read_gscr(struct ata_device *dev, u32 *gscr)
224{
225 static const int gscr_to_read[] = { 0, 1, 2, 32, 33, 64, 96 };
226 int i;
227
228 for (i = 0; i < ARRAY_SIZE(gscr_to_read); i++) {
229 int reg = gscr_to_read[i];
230 unsigned int err_mask;
231
232 err_mask = sata_pmp_read(link: dev->link, reg, r_val: &gscr[reg]);
233 if (err_mask) {
234 ata_dev_err(dev, "failed to read PMP GSCR[%d] (Emask=0x%x)\n",
235 reg, err_mask);
236 return -EIO;
237 }
238 }
239
240 return 0;
241}
242
243static const char *sata_pmp_spec_rev_str(const u32 *gscr)
244{
245 u32 rev = gscr[SATA_PMP_GSCR_REV];
246
247 if (rev & (1 << 3))
248 return "1.2";
249 if (rev & (1 << 2))
250 return "1.1";
251 if (rev & (1 << 1))
252 return "1.0";
253 return "<unknown>";
254}
255
256#define PMP_GSCR_SII_POL 129
257
258static int sata_pmp_configure(struct ata_device *dev, int print_info)
259{
260 struct ata_port *ap = dev->link->ap;
261 u32 *gscr = dev->gscr;
262 u16 vendor = sata_pmp_gscr_vendor(gscr);
263 u16 devid = sata_pmp_gscr_devid(gscr);
264 unsigned int err_mask = 0;
265 const char *reason;
266 int nr_ports, rc;
267
268 nr_ports = sata_pmp_gscr_ports(gscr);
269
270 if (nr_ports <= 0 || nr_ports > SATA_PMP_MAX_PORTS) {
271 rc = -EINVAL;
272 reason = "invalid nr_ports";
273 goto fail;
274 }
275
276 if ((ap->flags & ATA_FLAG_AN) &&
277 (gscr[SATA_PMP_GSCR_FEAT] & SATA_PMP_FEAT_NOTIFY))
278 dev->flags |= ATA_DFLAG_AN;
279
280 /* monitor SERR_PHYRDY_CHG on fan-out ports */
281 err_mask = sata_pmp_write(link: dev->link, reg: SATA_PMP_GSCR_ERROR_EN,
282 val: SERR_PHYRDY_CHG);
283 if (err_mask) {
284 rc = -EIO;
285 reason = "failed to write GSCR_ERROR_EN";
286 goto fail;
287 }
288
289 /* Disable sending Early R_OK.
290 * With "cached read" HDD testing and multiple ports busy on a SATA
291 * host controller, 3x26 PMP will very rarely drop a deferred
292 * R_OK that was intended for the host. Symptom will be all
293 * 5 drives under test will timeout, get reset, and recover.
294 */
295 if (vendor == 0x1095 && (devid == 0x3726 || devid == 0x3826)) {
296 u32 reg;
297
298 err_mask = sata_pmp_read(link: &ap->link, PMP_GSCR_SII_POL, r_val: &reg);
299 if (err_mask) {
300 rc = -EIO;
301 reason = "failed to read Sil3x26 Private Register";
302 goto fail;
303 }
304 reg &= ~0x1;
305 err_mask = sata_pmp_write(link: &ap->link, PMP_GSCR_SII_POL, val: reg);
306 if (err_mask) {
307 rc = -EIO;
308 reason = "failed to write Sil3x26 Private Register";
309 goto fail;
310 }
311 }
312
313 if (print_info) {
314 ata_dev_info(dev, "Port Multiplier %s, "
315 "0x%04x:0x%04x r%d, %d ports, feat 0x%x/0x%x\n",
316 sata_pmp_spec_rev_str(gscr), vendor, devid,
317 sata_pmp_gscr_rev(gscr),
318 nr_ports, gscr[SATA_PMP_GSCR_FEAT_EN],
319 gscr[SATA_PMP_GSCR_FEAT]);
320
321 if (!(dev->flags & ATA_DFLAG_AN))
322 ata_dev_info(dev,
323 "Asynchronous notification not supported, "
324 "hotplug won't work on fan-out ports. Use warm-plug instead.\n");
325 }
326
327 return 0;
328
329 fail:
330 ata_dev_err(dev,
331 "failed to configure Port Multiplier (%s, Emask=0x%x)\n",
332 reason, err_mask);
333 return rc;
334}
335
336static int sata_pmp_init_links (struct ata_port *ap, int nr_ports)
337{
338 struct ata_link *pmp_link = ap->pmp_link;
339 int i, err;
340
341 if (!pmp_link) {
342 pmp_link = kcalloc(n: SATA_PMP_MAX_PORTS, size: sizeof(pmp_link[0]),
343 GFP_NOIO);
344 if (!pmp_link)
345 return -ENOMEM;
346
347 for (i = 0; i < SATA_PMP_MAX_PORTS; i++)
348 ata_link_init(ap, link: &pmp_link[i], pmp: i);
349
350 ap->pmp_link = pmp_link;
351
352 for (i = 0; i < SATA_PMP_MAX_PORTS; i++) {
353 err = ata_tlink_add(link: &pmp_link[i]);
354 if (err) {
355 goto err_tlink;
356 }
357 }
358 }
359
360 for (i = 0; i < nr_ports; i++) {
361 struct ata_link *link = &pmp_link[i];
362 struct ata_eh_context *ehc = &link->eh_context;
363
364 link->flags = 0;
365 ehc->i.probe_mask |= ATA_ALL_DEVICES;
366 ehc->i.action |= ATA_EH_RESET;
367 }
368
369 return 0;
370 err_tlink:
371 while (--i >= 0)
372 ata_tlink_delete(link: &pmp_link[i]);
373 kfree(objp: pmp_link);
374 ap->pmp_link = NULL;
375 return err;
376}
377
378static void sata_pmp_quirks(struct ata_port *ap)
379{
380 u32 *gscr = ap->link.device->gscr;
381 u16 vendor = sata_pmp_gscr_vendor(gscr);
382 u16 devid = sata_pmp_gscr_devid(gscr);
383 struct ata_link *link;
384
385 if (vendor == 0x1095 && (devid == 0x3726 || devid == 0x3826)) {
386 /* sil3x26 quirks */
387 ata_for_each_link(link, ap, EDGE) {
388 /* link reports offline after LPM */
389 link->flags |= ATA_LFLAG_NO_LPM;
390
391 /*
392 * Class code report is unreliable and SRST times
393 * out under certain configurations.
394 */
395 if (link->pmp < 5)
396 link->flags |= ATA_LFLAG_NO_SRST |
397 ATA_LFLAG_ASSUME_ATA;
398
399 /* port 5 is for SEMB device and it doesn't like SRST */
400 if (link->pmp == 5)
401 link->flags |= ATA_LFLAG_NO_SRST |
402 ATA_LFLAG_ASSUME_SEMB;
403 }
404 } else if (vendor == 0x1095 && devid == 0x4723) {
405 /*
406 * sil4723 quirks
407 *
408 * Link reports offline after LPM. Class code report is
409 * unreliable. SIMG PMPs never got SRST reliable and the
410 * config device at port 2 locks up on SRST.
411 */
412 ata_for_each_link(link, ap, EDGE)
413 link->flags |= ATA_LFLAG_NO_LPM |
414 ATA_LFLAG_NO_SRST |
415 ATA_LFLAG_ASSUME_ATA;
416 } else if (vendor == 0x1095 && devid == 0x4726) {
417 /* sil4726 quirks */
418 ata_for_each_link(link, ap, EDGE) {
419 /* link reports offline after LPM */
420 link->flags |= ATA_LFLAG_NO_LPM;
421
422 /* Class code report is unreliable and SRST
423 * times out under certain configurations.
424 * Config device can be at port 0 or 5 and
425 * locks up on SRST.
426 */
427 if (link->pmp <= 5)
428 link->flags |= ATA_LFLAG_NO_SRST |
429 ATA_LFLAG_ASSUME_ATA;
430
431 /* Port 6 is for SEMB device which doesn't
432 * like SRST either.
433 */
434 if (link->pmp == 6)
435 link->flags |= ATA_LFLAG_NO_SRST |
436 ATA_LFLAG_ASSUME_SEMB;
437 }
438 } else if (vendor == 0x1095 && (devid == 0x5723 || devid == 0x5733 ||
439 devid == 0x5734 || devid == 0x5744)) {
440 /* sil5723/5744 quirks */
441
442 /* sil5723/5744 has either two or three downstream
443 * ports depending on operation mode. The last port
444 * is empty if any actual IO device is available or
445 * occupied by a pseudo configuration device
446 * otherwise. Don't try hard to recover it.
447 */
448 ap->pmp_link[ap->nr_pmp_links - 1].flags |= ATA_LFLAG_NO_RETRY;
449 } else if (vendor == 0x197b && (devid == 0x2352 || devid == 0x0325)) {
450 /*
451 * 0x2352: found in Thermaltake BlackX Duet, jmicron JMB350?
452 * 0x0325: jmicron JMB394.
453 */
454 ata_for_each_link(link, ap, EDGE) {
455 /* SRST breaks detection and disks get misclassified
456 * LPM disabled to avoid potential problems
457 */
458 link->flags |= ATA_LFLAG_NO_LPM |
459 ATA_LFLAG_NO_SRST |
460 ATA_LFLAG_ASSUME_ATA;
461 }
462 } else if (vendor == 0x11ab && devid == 0x4140) {
463 /* Marvell 4140 quirks */
464 ata_for_each_link(link, ap, EDGE) {
465 /* port 4 is for SEMB device and it doesn't like SRST */
466 if (link->pmp == 4)
467 link->flags |= ATA_LFLAG_DISABLED;
468 }
469 }
470}
471
472/**
473 * sata_pmp_attach - attach a SATA PMP device
474 * @dev: SATA PMP device to attach
475 *
476 * Configure and attach SATA PMP device @dev. This function is
477 * also responsible for allocating and initializing PMP links.
478 *
479 * LOCKING:
480 * Kernel thread context (may sleep).
481 *
482 * RETURNS:
483 * 0 on success, -errno on failure.
484 */
485int sata_pmp_attach(struct ata_device *dev)
486{
487 struct ata_link *link = dev->link;
488 struct ata_port *ap = link->ap;
489 unsigned long flags;
490 struct ata_link *tlink;
491 int rc;
492
493 /* is it hanging off the right place? */
494 if (!sata_pmp_supported(ap)) {
495 ata_dev_err(dev, "host does not support Port Multiplier\n");
496 return -EINVAL;
497 }
498
499 if (!ata_is_host_link(link)) {
500 ata_dev_err(dev, "Port Multipliers cannot be nested\n");
501 return -EINVAL;
502 }
503
504 if (dev->devno) {
505 ata_dev_err(dev, "Port Multiplier must be the first device\n");
506 return -EINVAL;
507 }
508
509 WARN_ON(link->pmp != 0);
510 link->pmp = SATA_PMP_CTRL_PORT;
511
512 /* read GSCR block */
513 rc = sata_pmp_read_gscr(dev, gscr: dev->gscr);
514 if (rc)
515 goto fail;
516
517 /* config PMP */
518 rc = sata_pmp_configure(dev, print_info: 1);
519 if (rc)
520 goto fail;
521
522 rc = sata_pmp_init_links(ap, sata_pmp_gscr_ports(dev->gscr));
523 if (rc) {
524 ata_dev_info(dev, "failed to initialize PMP links\n");
525 goto fail;
526 }
527
528 /* attach it */
529 spin_lock_irqsave(ap->lock, flags);
530 WARN_ON(ap->nr_pmp_links);
531 ap->nr_pmp_links = sata_pmp_gscr_ports(dev->gscr);
532 spin_unlock_irqrestore(lock: ap->lock, flags);
533
534 sata_pmp_quirks(ap);
535
536 if (ap->ops->pmp_attach)
537 ap->ops->pmp_attach(ap);
538
539 ata_for_each_link(tlink, ap, EDGE)
540 sata_link_init_spd(link: tlink);
541
542 return 0;
543
544 fail:
545 link->pmp = 0;
546 return rc;
547}
548
549/**
550 * sata_pmp_detach - detach a SATA PMP device
551 * @dev: SATA PMP device to detach
552 *
553 * Detach SATA PMP device @dev. This function is also
554 * responsible for deconfiguring PMP links.
555 *
556 * LOCKING:
557 * Kernel thread context (may sleep).
558 */
559static void sata_pmp_detach(struct ata_device *dev)
560{
561 struct ata_link *link = dev->link;
562 struct ata_port *ap = link->ap;
563 struct ata_link *tlink;
564 unsigned long flags;
565
566 ata_dev_info(dev, "Port Multiplier detaching\n");
567
568 WARN_ON(!ata_is_host_link(link) || dev->devno ||
569 link->pmp != SATA_PMP_CTRL_PORT);
570
571 if (ap->ops->pmp_detach)
572 ap->ops->pmp_detach(ap);
573
574 ata_for_each_link(tlink, ap, EDGE)
575 ata_eh_detach_dev(dev: tlink->device);
576
577 spin_lock_irqsave(ap->lock, flags);
578 ap->nr_pmp_links = 0;
579 link->pmp = 0;
580 spin_unlock_irqrestore(lock: ap->lock, flags);
581}
582
583/**
584 * sata_pmp_same_pmp - does new GSCR matches the configured PMP?
585 * @dev: PMP device to compare against
586 * @new_gscr: GSCR block of the new device
587 *
588 * Compare @new_gscr against @dev and determine whether @dev is
589 * the PMP described by @new_gscr.
590 *
591 * LOCKING:
592 * None.
593 *
594 * RETURNS:
595 * 1 if @dev matches @new_gscr, 0 otherwise.
596 */
597static int sata_pmp_same_pmp(struct ata_device *dev, const u32 *new_gscr)
598{
599 const u32 *old_gscr = dev->gscr;
600 u16 old_vendor, new_vendor, old_devid, new_devid;
601 int old_nr_ports, new_nr_ports;
602
603 old_vendor = sata_pmp_gscr_vendor(old_gscr);
604 new_vendor = sata_pmp_gscr_vendor(new_gscr);
605 old_devid = sata_pmp_gscr_devid(old_gscr);
606 new_devid = sata_pmp_gscr_devid(new_gscr);
607 old_nr_ports = sata_pmp_gscr_ports(old_gscr);
608 new_nr_ports = sata_pmp_gscr_ports(new_gscr);
609
610 if (old_vendor != new_vendor) {
611 ata_dev_info(dev,
612 "Port Multiplier vendor mismatch '0x%x' != '0x%x'\n",
613 old_vendor, new_vendor);
614 return 0;
615 }
616
617 if (old_devid != new_devid) {
618 ata_dev_info(dev,
619 "Port Multiplier device ID mismatch '0x%x' != '0x%x'\n",
620 old_devid, new_devid);
621 return 0;
622 }
623
624 if (old_nr_ports != new_nr_ports) {
625 ata_dev_info(dev,
626 "Port Multiplier nr_ports mismatch '0x%x' != '0x%x'\n",
627 old_nr_ports, new_nr_ports);
628 return 0;
629 }
630
631 return 1;
632}
633
634/**
635 * sata_pmp_revalidate - revalidate SATA PMP
636 * @dev: PMP device to revalidate
637 * @new_class: new class code
638 *
639 * Re-read GSCR block and make sure @dev is still attached to the
640 * port and properly configured.
641 *
642 * LOCKING:
643 * Kernel thread context (may sleep).
644 *
645 * RETURNS:
646 * 0 on success, -errno otherwise.
647 */
648static int sata_pmp_revalidate(struct ata_device *dev, unsigned int new_class)
649{
650 struct ata_link *link = dev->link;
651 struct ata_port *ap = link->ap;
652 u32 *gscr = (void *)ap->sector_buf;
653 int rc;
654
655 ata_eh_about_to_do(link, NULL, action: ATA_EH_REVALIDATE);
656
657 if (!ata_dev_enabled(dev)) {
658 rc = -ENODEV;
659 goto fail;
660 }
661
662 /* wrong class? */
663 if (ata_class_enabled(class: new_class) && new_class != ATA_DEV_PMP) {
664 rc = -ENODEV;
665 goto fail;
666 }
667
668 /* read GSCR */
669 rc = sata_pmp_read_gscr(dev, gscr);
670 if (rc)
671 goto fail;
672
673 /* is the pmp still there? */
674 if (!sata_pmp_same_pmp(dev, new_gscr: gscr)) {
675 rc = -ENODEV;
676 goto fail;
677 }
678
679 memcpy(dev->gscr, gscr, sizeof(gscr[0]) * SATA_PMP_GSCR_DWORDS);
680
681 rc = sata_pmp_configure(dev, print_info: 0);
682 if (rc)
683 goto fail;
684
685 ata_eh_done(link, NULL, action: ATA_EH_REVALIDATE);
686
687 return 0;
688
689 fail:
690 ata_dev_err(dev, "PMP revalidation failed (errno=%d)\n", rc);
691 return rc;
692}
693
694/**
695 * sata_pmp_revalidate_quick - revalidate SATA PMP quickly
696 * @dev: PMP device to revalidate
697 *
698 * Make sure the attached PMP is accessible.
699 *
700 * LOCKING:
701 * Kernel thread context (may sleep).
702 *
703 * RETURNS:
704 * 0 on success, -errno otherwise.
705 */
706static int sata_pmp_revalidate_quick(struct ata_device *dev)
707{
708 unsigned int err_mask;
709 u32 prod_id;
710
711 err_mask = sata_pmp_read(link: dev->link, reg: SATA_PMP_GSCR_PROD_ID, r_val: &prod_id);
712 if (err_mask) {
713 ata_dev_err(dev,
714 "failed to read PMP product ID (Emask=0x%x)\n",
715 err_mask);
716 return -EIO;
717 }
718
719 if (prod_id != dev->gscr[SATA_PMP_GSCR_PROD_ID]) {
720 ata_dev_err(dev, "PMP product ID mismatch\n");
721 /* something weird is going on, request full PMP recovery */
722 return -EIO;
723 }
724
725 return 0;
726}
727
728/**
729 * sata_pmp_eh_recover_pmp - recover PMP
730 * @ap: ATA port PMP is attached to
731 * @prereset: prereset method (can be NULL)
732 * @softreset: softreset method
733 * @hardreset: hardreset method
734 * @postreset: postreset method (can be NULL)
735 *
736 * Recover PMP attached to @ap. Recovery procedure is somewhat
737 * similar to that of ata_eh_recover() except that reset should
738 * always be performed in hard->soft sequence and recovery
739 * failure results in PMP detachment.
740 *
741 * LOCKING:
742 * Kernel thread context (may sleep).
743 *
744 * RETURNS:
745 * 0 on success, -errno on failure.
746 */
747static int sata_pmp_eh_recover_pmp(struct ata_port *ap,
748 ata_prereset_fn_t prereset, ata_reset_fn_t softreset,
749 ata_reset_fn_t hardreset, ata_postreset_fn_t postreset)
750{
751 struct ata_link *link = &ap->link;
752 struct ata_eh_context *ehc = &link->eh_context;
753 struct ata_device *dev = link->device;
754 int tries = ATA_EH_PMP_TRIES;
755 int detach = 0, rc = 0;
756 int reval_failed = 0;
757
758 if (dev->flags & ATA_DFLAG_DETACH) {
759 detach = 1;
760 rc = -ENODEV;
761 goto fail;
762 }
763
764 retry:
765 ehc->classes[0] = ATA_DEV_UNKNOWN;
766
767 if (ehc->i.action & ATA_EH_RESET) {
768 struct ata_link *tlink;
769
770 /* reset */
771 rc = ata_eh_reset(link, classify: 0, prereset, softreset, hardreset,
772 postreset);
773 if (rc) {
774 ata_link_err(link, "failed to reset PMP, giving up\n");
775 goto fail;
776 }
777
778 /* PMP is reset, SErrors cannot be trusted, scan all */
779 ata_for_each_link(tlink, ap, EDGE) {
780 struct ata_eh_context *ehc = &tlink->eh_context;
781
782 ehc->i.probe_mask |= ATA_ALL_DEVICES;
783 ehc->i.action |= ATA_EH_RESET;
784 }
785 }
786
787 /* If revalidation is requested, revalidate and reconfigure;
788 * otherwise, do quick revalidation.
789 */
790 if (ehc->i.action & ATA_EH_REVALIDATE)
791 rc = sata_pmp_revalidate(dev, new_class: ehc->classes[0]);
792 else
793 rc = sata_pmp_revalidate_quick(dev);
794
795 if (rc) {
796 tries--;
797
798 if (rc == -ENODEV) {
799 ehc->i.probe_mask |= ATA_ALL_DEVICES;
800 detach = 1;
801 /* give it just two more chances */
802 tries = min(tries, 2);
803 }
804
805 if (tries) {
806 /* consecutive revalidation failures? speed down */
807 if (reval_failed)
808 sata_down_spd_limit(link, spd_limit: 0);
809 else
810 reval_failed = 1;
811
812 ehc->i.action |= ATA_EH_RESET;
813 goto retry;
814 } else {
815 ata_dev_err(dev,
816 "failed to recover PMP after %d tries, giving up\n",
817 ATA_EH_PMP_TRIES);
818 goto fail;
819 }
820 }
821
822 /* okay, PMP resurrected */
823 ehc->i.flags = 0;
824
825 return 0;
826
827 fail:
828 sata_pmp_detach(dev);
829 if (detach)
830 ata_eh_detach_dev(dev);
831 else
832 ata_dev_disable(dev);
833
834 return rc;
835}
836
837static int sata_pmp_eh_handle_disabled_links(struct ata_port *ap)
838{
839 struct ata_link *link;
840 unsigned long flags;
841 int rc;
842
843 spin_lock_irqsave(ap->lock, flags);
844
845 ata_for_each_link(link, ap, EDGE) {
846 if (!(link->flags & ATA_LFLAG_DISABLED))
847 continue;
848
849 spin_unlock_irqrestore(lock: ap->lock, flags);
850
851 /* Some PMPs require hardreset sequence to get
852 * SError.N working.
853 */
854 sata_link_hardreset(link, timing: sata_deb_timing_normal,
855 deadline: ata_deadline(from_jiffies: jiffies, timeout_msecs: ATA_TMOUT_INTERNAL_QUICK),
856 NULL, NULL);
857
858 /* unconditionally clear SError.N */
859 rc = sata_scr_write(link, reg: SCR_ERROR, val: SERR_PHYRDY_CHG);
860 if (rc) {
861 ata_link_err(link,
862 "failed to clear SError.N (errno=%d)\n",
863 rc);
864 return rc;
865 }
866
867 spin_lock_irqsave(ap->lock, flags);
868 }
869
870 spin_unlock_irqrestore(lock: ap->lock, flags);
871
872 return 0;
873}
874
875static int sata_pmp_handle_link_fail(struct ata_link *link, int *link_tries)
876{
877 struct ata_port *ap = link->ap;
878 unsigned long flags;
879
880 if (link_tries[link->pmp] && --link_tries[link->pmp])
881 return 1;
882
883 /* disable this link */
884 if (!(link->flags & ATA_LFLAG_DISABLED)) {
885 ata_link_warn(link,
886 "failed to recover link after %d tries, disabling\n",
887 ATA_EH_PMP_LINK_TRIES);
888
889 spin_lock_irqsave(ap->lock, flags);
890 link->flags |= ATA_LFLAG_DISABLED;
891 spin_unlock_irqrestore(lock: ap->lock, flags);
892 }
893
894 ata_dev_disable(dev: link->device);
895 link->eh_context.i.action = 0;
896
897 return 0;
898}
899
900/**
901 * sata_pmp_eh_recover - recover PMP-enabled port
902 * @ap: ATA port to recover
903 *
904 * Drive EH recovery operation for PMP enabled port @ap. This
905 * function recovers host and PMP ports with proper retrials and
906 * fallbacks. Actual recovery operations are performed using
907 * ata_eh_recover() and sata_pmp_eh_recover_pmp().
908 *
909 * LOCKING:
910 * Kernel thread context (may sleep).
911 *
912 * RETURNS:
913 * 0 on success, -errno on failure.
914 */
915static int sata_pmp_eh_recover(struct ata_port *ap)
916{
917 struct ata_port_operations *ops = ap->ops;
918 int pmp_tries, link_tries[SATA_PMP_MAX_PORTS];
919 struct ata_link *pmp_link = &ap->link;
920 struct ata_device *pmp_dev = pmp_link->device;
921 struct ata_eh_context *pmp_ehc = &pmp_link->eh_context;
922 u32 *gscr = pmp_dev->gscr;
923 struct ata_link *link;
924 struct ata_device *dev;
925 unsigned int err_mask;
926 u32 gscr_error, sntf;
927 int cnt, rc;
928
929 pmp_tries = ATA_EH_PMP_TRIES;
930 ata_for_each_link(link, ap, EDGE)
931 link_tries[link->pmp] = ATA_EH_PMP_LINK_TRIES;
932
933 retry:
934 /* PMP attached? */
935 if (!sata_pmp_attached(ap)) {
936 rc = ata_eh_recover(ap, prereset: ops->prereset, softreset: ops->softreset,
937 hardreset: ops->hardreset, postreset: ops->postreset, NULL);
938 if (rc) {
939 ata_for_each_dev(dev, &ap->link, ALL)
940 ata_dev_disable(dev);
941 return rc;
942 }
943
944 if (pmp_dev->class != ATA_DEV_PMP)
945 return 0;
946
947 /* new PMP online */
948 ata_for_each_link(link, ap, EDGE)
949 link_tries[link->pmp] = ATA_EH_PMP_LINK_TRIES;
950
951 /* fall through */
952 }
953
954 /* recover pmp */
955 rc = sata_pmp_eh_recover_pmp(ap, prereset: ops->prereset, softreset: ops->softreset,
956 hardreset: ops->hardreset, postreset: ops->postreset);
957 if (rc)
958 goto pmp_fail;
959
960 /* PHY event notification can disturb reset and other recovery
961 * operations. Turn it off.
962 */
963 if (gscr[SATA_PMP_GSCR_FEAT_EN] & SATA_PMP_FEAT_NOTIFY) {
964 gscr[SATA_PMP_GSCR_FEAT_EN] &= ~SATA_PMP_FEAT_NOTIFY;
965
966 err_mask = sata_pmp_write(link: pmp_link, reg: SATA_PMP_GSCR_FEAT_EN,
967 val: gscr[SATA_PMP_GSCR_FEAT_EN]);
968 if (err_mask) {
969 ata_link_warn(pmp_link,
970 "failed to disable NOTIFY (err_mask=0x%x)\n",
971 err_mask);
972 goto pmp_fail;
973 }
974 }
975
976 /* handle disabled links */
977 rc = sata_pmp_eh_handle_disabled_links(ap);
978 if (rc)
979 goto pmp_fail;
980
981 /* recover links */
982 rc = ata_eh_recover(ap, prereset: ops->pmp_prereset, softreset: ops->pmp_softreset,
983 hardreset: ops->pmp_hardreset, postreset: ops->pmp_postreset, r_failed_disk: &link);
984 if (rc)
985 goto link_fail;
986
987 /* clear SNotification */
988 rc = sata_scr_read(link: &ap->link, reg: SCR_NOTIFICATION, val: &sntf);
989 if (rc == 0)
990 sata_scr_write(link: &ap->link, reg: SCR_NOTIFICATION, val: sntf);
991
992 /*
993 * If LPM is active on any fan-out port, hotplug wouldn't
994 * work. Return w/ PHY event notification disabled.
995 */
996 ata_for_each_link(link, ap, EDGE)
997 if (link->lpm_policy > ATA_LPM_MAX_POWER)
998 return 0;
999
1000 /*
1001 * Connection status might have changed while resetting other
1002 * links, enable notification and check SATA_PMP_GSCR_ERROR
1003 * before returning.
1004 */
1005
1006 /* enable notification */
1007 if (pmp_dev->flags & ATA_DFLAG_AN) {
1008 gscr[SATA_PMP_GSCR_FEAT_EN] |= SATA_PMP_FEAT_NOTIFY;
1009
1010 err_mask = sata_pmp_write(link: pmp_link, reg: SATA_PMP_GSCR_FEAT_EN,
1011 val: gscr[SATA_PMP_GSCR_FEAT_EN]);
1012 if (err_mask) {
1013 ata_dev_err(pmp_dev,
1014 "failed to write PMP_FEAT_EN (Emask=0x%x)\n",
1015 err_mask);
1016 rc = -EIO;
1017 goto pmp_fail;
1018 }
1019 }
1020
1021 /* check GSCR_ERROR */
1022 err_mask = sata_pmp_read(link: pmp_link, reg: SATA_PMP_GSCR_ERROR, r_val: &gscr_error);
1023 if (err_mask) {
1024 ata_dev_err(pmp_dev,
1025 "failed to read PMP_GSCR_ERROR (Emask=0x%x)\n",
1026 err_mask);
1027 rc = -EIO;
1028 goto pmp_fail;
1029 }
1030
1031 cnt = 0;
1032 ata_for_each_link(link, ap, EDGE) {
1033 if (!(gscr_error & (1 << link->pmp)))
1034 continue;
1035
1036 if (sata_pmp_handle_link_fail(link, link_tries)) {
1037 ata_ehi_hotplugged(ehi: &link->eh_context.i);
1038 cnt++;
1039 } else {
1040 ata_link_warn(link,
1041 "PHY status changed but maxed out on retries, giving up\n");
1042 ata_link_warn(link,
1043 "Manually issue scan to resume this link\n");
1044 }
1045 }
1046
1047 if (cnt) {
1048 ata_port_info(ap,
1049 "PMP SError.N set for some ports, repeating recovery\n");
1050 goto retry;
1051 }
1052
1053 return 0;
1054
1055 link_fail:
1056 if (sata_pmp_handle_link_fail(link, link_tries)) {
1057 pmp_ehc->i.action |= ATA_EH_RESET;
1058 goto retry;
1059 }
1060
1061 /* fall through */
1062 pmp_fail:
1063 /* Control always ends up here after detaching PMP. Shut up
1064 * and return if we're unloading.
1065 */
1066 if (ap->pflags & ATA_PFLAG_UNLOADING)
1067 return rc;
1068
1069 if (!sata_pmp_attached(ap))
1070 goto retry;
1071
1072 if (--pmp_tries) {
1073 pmp_ehc->i.action |= ATA_EH_RESET;
1074 goto retry;
1075 }
1076
1077 ata_port_err(ap, "failed to recover PMP after %d tries, giving up\n",
1078 ATA_EH_PMP_TRIES);
1079 sata_pmp_detach(dev: pmp_dev);
1080 ata_dev_disable(dev: pmp_dev);
1081
1082 return rc;
1083}
1084
1085/**
1086 * sata_pmp_error_handler - do standard error handling for PMP-enabled host
1087 * @ap: host port to handle error for
1088 *
1089 * Perform standard error handling sequence for PMP-enabled host
1090 * @ap.
1091 *
1092 * LOCKING:
1093 * Kernel thread context (may sleep).
1094 */
1095void sata_pmp_error_handler(struct ata_port *ap)
1096{
1097 ata_eh_autopsy(ap);
1098 ata_eh_report(ap);
1099 sata_pmp_eh_recover(ap);
1100 ata_eh_finish(ap);
1101}
1102
1103EXPORT_SYMBOL_GPL(sata_pmp_port_ops);
1104EXPORT_SYMBOL_GPL(sata_pmp_qc_defer_cmd_switch);
1105EXPORT_SYMBOL_GPL(sata_pmp_error_handler);
1106

source code of linux/drivers/ata/libata-pmp.c