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authorMatthew R. Ochs <mrochs@linux.vnet.ibm.com>2015-06-09 18:15:52 -0400
committerJames Bottomley <JBottomley@Odin.com>2015-07-31 00:02:01 -0400
commitc21e0bbfc48509a776ec4a39bd9a0fb45a9c315b (patch)
treeec2bc76bd16eb59c3efbd7af05c8364eb4a9ecf0 /drivers/scsi/cxlflash/main.c
parent2dc127bb299d1c7436a08e79193bd0251068356e (diff)
cxlflash: Base support for IBM CXL Flash Adapter
SCSI device driver to support filesystem access on the IBM CXL Flash adapter. Supported-by: Stephen Bates <stephen.bates@pmcs.com> Reviewed-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Diffstat (limited to 'drivers/scsi/cxlflash/main.c')
-rw-r--r--drivers/scsi/cxlflash/main.c2294
1 files changed, 2294 insertions, 0 deletions
diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
new file mode 100644
index 000000000000..0720d2f13c2a
--- /dev/null
+++ b/drivers/scsi/cxlflash/main.c
@@ -0,0 +1,2294 @@
1/*
2 * CXL Flash Device Driver
3 *
4 * Written by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>, IBM Corporation
5 * Matthew R. Ochs <mrochs@linux.vnet.ibm.com>, IBM Corporation
6 *
7 * Copyright (C) 2015 IBM Corporation
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
13 */
14
15#include <linux/delay.h>
16#include <linux/list.h>
17#include <linux/module.h>
18#include <linux/pci.h>
19
20#include <asm/unaligned.h>
21
22#include <misc/cxl.h>
23
24#include <scsi/scsi_cmnd.h>
25#include <scsi/scsi_host.h>
26
27#include "main.h"
28#include "sislite.h"
29#include "common.h"
30
31MODULE_DESCRIPTION(CXLFLASH_ADAPTER_NAME);
32MODULE_AUTHOR("Manoj N. Kumar <manoj@linux.vnet.ibm.com>");
33MODULE_AUTHOR("Matthew R. Ochs <mrochs@linux.vnet.ibm.com>");
34MODULE_LICENSE("GPL");
35
36
37/**
38 * cxlflash_cmd_checkout() - checks out an AFU command
39 * @afu: AFU to checkout from.
40 *
41 * Commands are checked out in a round-robin fashion. Note that since
42 * the command pool is larger than the hardware queue, the majority of
43 * times we will only loop once or twice before getting a command. The
44 * buffer and CDB within the command are initialized (zeroed) prior to
45 * returning.
46 *
47 * Return: The checked out command or NULL when command pool is empty.
48 */
49struct afu_cmd *cxlflash_cmd_checkout(struct afu *afu)
50{
51 int k, dec = CXLFLASH_NUM_CMDS;
52 struct afu_cmd *cmd;
53
54 while (dec--) {
55 k = (afu->cmd_couts++ & (CXLFLASH_NUM_CMDS - 1));
56
57 cmd = &afu->cmd[k];
58
59 if (!atomic_dec_if_positive(&cmd->free)) {
60 pr_debug("%s: returning found index=%d\n",
61 __func__, cmd->slot);
62 memset(cmd->buf, 0, CMD_BUFSIZE);
63 memset(cmd->rcb.cdb, 0, sizeof(cmd->rcb.cdb));
64 return cmd;
65 }
66 }
67
68 return NULL;
69}
70
71/**
72 * cxlflash_cmd_checkin() - checks in an AFU command
73 * @cmd: AFU command to checkin.
74 *
75 * Safe to pass commands that have already been checked in. Several
76 * internal tracking fields are reset as part of the checkin. Note
77 * that these are intentionally reset prior to toggling the free bit
78 * to avoid clobbering values in the event that the command is checked
79 * out right away.
80 */
81void cxlflash_cmd_checkin(struct afu_cmd *cmd)
82{
83 cmd->rcb.scp = NULL;
84 cmd->rcb.timeout = 0;
85 cmd->sa.ioasc = 0;
86 cmd->cmd_tmf = false;
87 cmd->sa.host_use[0] = 0; /* clears both completion and retry bytes */
88
89 if (unlikely(atomic_inc_return(&cmd->free) != 1)) {
90 pr_err("%s: Freeing cmd (%d) that is not in use!\n",
91 __func__, cmd->slot);
92 return;
93 }
94
95 pr_debug("%s: released cmd %p index=%d\n", __func__, cmd, cmd->slot);
96}
97
98/**
99 * process_cmd_err() - command error handler
100 * @cmd: AFU command that experienced the error.
101 * @scp: SCSI command associated with the AFU command in error.
102 *
103 * Translates error bits from AFU command to SCSI command results.
104 */
105static void process_cmd_err(struct afu_cmd *cmd, struct scsi_cmnd *scp)
106{
107 struct sisl_ioarcb *ioarcb;
108 struct sisl_ioasa *ioasa;
109
110 if (unlikely(!cmd))
111 return;
112
113 ioarcb = &(cmd->rcb);
114 ioasa = &(cmd->sa);
115
116 if (ioasa->rc.flags & SISL_RC_FLAGS_UNDERRUN) {
117 pr_debug("%s: cmd underrun cmd = %p scp = %p\n",
118 __func__, cmd, scp);
119 scp->result = (DID_ERROR << 16);
120 }
121
122 if (ioasa->rc.flags & SISL_RC_FLAGS_OVERRUN) {
123 pr_debug("%s: cmd underrun cmd = %p scp = %p\n",
124 __func__, cmd, scp);
125 scp->result = (DID_ERROR << 16);
126 }
127
128 pr_debug("%s: cmd failed afu_rc=%d scsi_rc=%d fc_rc=%d "
129 "afu_extra=0x%X, scsi_entra=0x%X, fc_extra=0x%X\n",
130 __func__, ioasa->rc.afu_rc, ioasa->rc.scsi_rc,
131 ioasa->rc.fc_rc, ioasa->afu_extra, ioasa->scsi_extra,
132 ioasa->fc_extra);
133
134 if (ioasa->rc.scsi_rc) {
135 /* We have a SCSI status */
136 if (ioasa->rc.flags & SISL_RC_FLAGS_SENSE_VALID) {
137 memcpy(scp->sense_buffer, ioasa->sense_data,
138 SISL_SENSE_DATA_LEN);
139 scp->result = ioasa->rc.scsi_rc;
140 } else
141 scp->result = ioasa->rc.scsi_rc | (DID_ERROR << 16);
142 }
143
144 /*
145 * We encountered an error. Set scp->result based on nature
146 * of error.
147 */
148 if (ioasa->rc.fc_rc) {
149 /* We have an FC status */
150 switch (ioasa->rc.fc_rc) {
151 case SISL_FC_RC_LINKDOWN:
152 scp->result = (DID_REQUEUE << 16);
153 break;
154 case SISL_FC_RC_RESID:
155 /* This indicates an FCP resid underrun */
156 if (!(ioasa->rc.flags & SISL_RC_FLAGS_OVERRUN)) {
157 /* If the SISL_RC_FLAGS_OVERRUN flag was set,
158 * then we will handle this error else where.
159 * If not then we must handle it here.
160 * This is probably an AFU bug. We will
161 * attempt a retry to see if that resolves it.
162 */
163 scp->result = (DID_ERROR << 16);
164 }
165 break;
166 case SISL_FC_RC_RESIDERR:
167 /* Resid mismatch between adapter and device */
168 case SISL_FC_RC_TGTABORT:
169 case SISL_FC_RC_ABORTOK:
170 case SISL_FC_RC_ABORTFAIL:
171 case SISL_FC_RC_NOLOGI:
172 case SISL_FC_RC_ABORTPEND:
173 case SISL_FC_RC_WRABORTPEND:
174 case SISL_FC_RC_NOEXP:
175 case SISL_FC_RC_INUSE:
176 scp->result = (DID_ERROR << 16);
177 break;
178 }
179 }
180
181 if (ioasa->rc.afu_rc) {
182 /* We have an AFU error */
183 switch (ioasa->rc.afu_rc) {
184 case SISL_AFU_RC_NO_CHANNELS:
185 scp->result = (DID_MEDIUM_ERROR << 16);
186 break;
187 case SISL_AFU_RC_DATA_DMA_ERR:
188 switch (ioasa->afu_extra) {
189 case SISL_AFU_DMA_ERR_PAGE_IN:
190 /* Retry */
191 scp->result = (DID_IMM_RETRY << 16);
192 break;
193 case SISL_AFU_DMA_ERR_INVALID_EA:
194 default:
195 scp->result = (DID_ERROR << 16);
196 }
197 break;
198 case SISL_AFU_RC_OUT_OF_DATA_BUFS:
199 /* Retry */
200 scp->result = (DID_ALLOC_FAILURE << 16);
201 break;
202 default:
203 scp->result = (DID_ERROR << 16);
204 }
205 }
206}
207
208/**
209 * cmd_complete() - command completion handler
210 * @cmd: AFU command that has completed.
211 *
212 * Prepares and submits command that has either completed or timed out to
213 * the SCSI stack. Checks AFU command back into command pool for non-internal
214 * (rcb.scp populated) commands.
215 */
216static void cmd_complete(struct afu_cmd *cmd)
217{
218 struct scsi_cmnd *scp;
219 u32 resid;
220 ulong lock_flags;
221 struct afu *afu = cmd->parent;
222 struct cxlflash_cfg *cfg = afu->parent;
223 bool cmd_is_tmf;
224
225 spin_lock_irqsave(&cmd->slock, lock_flags);
226 cmd->sa.host_use_b[0] |= B_DONE;
227 spin_unlock_irqrestore(&cmd->slock, lock_flags);
228
229 if (cmd->rcb.scp) {
230 scp = cmd->rcb.scp;
231 if (unlikely(cmd->sa.rc.afu_rc ||
232 cmd->sa.rc.scsi_rc ||
233 cmd->sa.rc.fc_rc))
234 process_cmd_err(cmd, scp);
235 else
236 scp->result = (DID_OK << 16);
237
238 resid = cmd->sa.resid;
239 cmd_is_tmf = cmd->cmd_tmf;
240 cxlflash_cmd_checkin(cmd); /* Don't use cmd after here */
241
242 pr_debug("%s: calling scsi_set_resid, scp=%p "
243 "result=%X resid=%d\n", __func__,
244 scp, scp->result, resid);
245
246 scsi_set_resid(scp, resid);
247 scsi_dma_unmap(scp);
248 scp->scsi_done(scp);
249
250 if (cmd_is_tmf) {
251 spin_lock_irqsave(&cfg->tmf_waitq.lock, lock_flags);
252 cfg->tmf_active = false;
253 wake_up_all_locked(&cfg->tmf_waitq);
254 spin_unlock_irqrestore(&cfg->tmf_waitq.lock,
255 lock_flags);
256 }
257 } else
258 complete(&cmd->cevent);
259}
260
261/**
262 * send_tmf() - sends a Task Management Function (TMF)
263 * @afu: AFU to checkout from.
264 * @scp: SCSI command from stack.
265 * @tmfcmd: TMF command to send.
266 *
267 * Return:
268 * 0 on success
269 * SCSI_MLQUEUE_HOST_BUSY when host is busy
270 */
271static int send_tmf(struct afu *afu, struct scsi_cmnd *scp, u64 tmfcmd)
272{
273 struct afu_cmd *cmd;
274
275 u32 port_sel = scp->device->channel + 1;
276 short lflag = 0;
277 struct Scsi_Host *host = scp->device->host;
278 struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)host->hostdata;
279 ulong lock_flags;
280 int rc = 0;
281
282 cmd = cxlflash_cmd_checkout(afu);
283 if (unlikely(!cmd)) {
284 pr_err("%s: could not get a free command\n", __func__);
285 rc = SCSI_MLQUEUE_HOST_BUSY;
286 goto out;
287 }
288
289 /* If a Task Management Function is active, do not send one more.
290 */
291 spin_lock_irqsave(&cfg->tmf_waitq.lock, lock_flags);
292 if (cfg->tmf_active)
293 wait_event_interruptible_locked_irq(cfg->tmf_waitq,
294 !cfg->tmf_active);
295 cfg->tmf_active = true;
296 cmd->cmd_tmf = true;
297 spin_unlock_irqrestore(&cfg->tmf_waitq.lock, lock_flags);
298
299 cmd->rcb.ctx_id = afu->ctx_hndl;
300 cmd->rcb.port_sel = port_sel;
301 cmd->rcb.lun_id = lun_to_lunid(scp->device->lun);
302
303 lflag = SISL_REQ_FLAGS_TMF_CMD;
304
305 cmd->rcb.req_flags = (SISL_REQ_FLAGS_PORT_LUN_ID |
306 SISL_REQ_FLAGS_SUP_UNDERRUN | lflag);
307
308 /* Stash the scp in the reserved field, for reuse during interrupt */
309 cmd->rcb.scp = scp;
310
311 /* Copy the CDB from the cmd passed in */
312 memcpy(cmd->rcb.cdb, &tmfcmd, sizeof(tmfcmd));
313
314 /* Send the command */
315 rc = cxlflash_send_cmd(afu, cmd);
316 if (unlikely(rc)) {
317 cxlflash_cmd_checkin(cmd);
318 spin_lock_irqsave(&cfg->tmf_waitq.lock, lock_flags);
319 cfg->tmf_active = false;
320 spin_unlock_irqrestore(&cfg->tmf_waitq.lock, lock_flags);
321 goto out;
322 }
323
324 spin_lock_irqsave(&cfg->tmf_waitq.lock, lock_flags);
325 wait_event_interruptible_locked_irq(cfg->tmf_waitq, !cfg->tmf_active);
326 spin_unlock_irqrestore(&cfg->tmf_waitq.lock, lock_flags);
327out:
328 return rc;
329}
330
331/**
332 * cxlflash_driver_info() - information handler for this host driver
333 * @host: SCSI host associated with device.
334 *
335 * Return: A string describing the device.
336 */
337static const char *cxlflash_driver_info(struct Scsi_Host *host)
338{
339 return CXLFLASH_ADAPTER_NAME;
340}
341
342/**
343 * cxlflash_queuecommand() - sends a mid-layer request
344 * @host: SCSI host associated with device.
345 * @scp: SCSI command to send.
346 *
347 * Return:
348 * 0 on success
349 * SCSI_MLQUEUE_HOST_BUSY when host is busy
350 */
351static int cxlflash_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scp)
352{
353 struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)host->hostdata;
354 struct afu *afu = cfg->afu;
355 struct pci_dev *pdev = cfg->dev;
356 struct afu_cmd *cmd;
357 u32 port_sel = scp->device->channel + 1;
358 int nseg, i, ncount;
359 struct scatterlist *sg;
360 ulong lock_flags;
361 short lflag = 0;
362 int rc = 0;
363
364 pr_debug("%s: (scp=%p) %d/%d/%d/%llu cdb=(%08X-%08X-%08X-%08X)\n",
365 __func__, scp, host->host_no, scp->device->channel,
366 scp->device->id, scp->device->lun,
367 get_unaligned_be32(&((u32 *)scp->cmnd)[0]),
368 get_unaligned_be32(&((u32 *)scp->cmnd)[1]),
369 get_unaligned_be32(&((u32 *)scp->cmnd)[2]),
370 get_unaligned_be32(&((u32 *)scp->cmnd)[3]));
371
372 /* If a Task Management Function is active, wait for it to complete
373 * before continuing with regular commands.
374 */
375 spin_lock_irqsave(&cfg->tmf_waitq.lock, lock_flags);
376 if (cfg->tmf_active) {
377 spin_unlock_irqrestore(&cfg->tmf_waitq.lock, lock_flags);
378 rc = SCSI_MLQUEUE_HOST_BUSY;
379 goto out;
380 }
381 spin_unlock_irqrestore(&cfg->tmf_waitq.lock, lock_flags);
382
383 cmd = cxlflash_cmd_checkout(afu);
384 if (unlikely(!cmd)) {
385 pr_err("%s: could not get a free command\n", __func__);
386 rc = SCSI_MLQUEUE_HOST_BUSY;
387 goto out;
388 }
389
390 cmd->rcb.ctx_id = afu->ctx_hndl;
391 cmd->rcb.port_sel = port_sel;
392 cmd->rcb.lun_id = lun_to_lunid(scp->device->lun);
393
394 if (scp->sc_data_direction == DMA_TO_DEVICE)
395 lflag = SISL_REQ_FLAGS_HOST_WRITE;
396 else
397 lflag = SISL_REQ_FLAGS_HOST_READ;
398
399 cmd->rcb.req_flags = (SISL_REQ_FLAGS_PORT_LUN_ID |
400 SISL_REQ_FLAGS_SUP_UNDERRUN | lflag);
401
402 /* Stash the scp in the reserved field, for reuse during interrupt */
403 cmd->rcb.scp = scp;
404
405 nseg = scsi_dma_map(scp);
406 if (unlikely(nseg < 0)) {
407 dev_err(&pdev->dev, "%s: Fail DMA map! nseg=%d\n",
408 __func__, nseg);
409 rc = SCSI_MLQUEUE_HOST_BUSY;
410 goto out;
411 }
412
413 ncount = scsi_sg_count(scp);
414 scsi_for_each_sg(scp, sg, ncount, i) {
415 cmd->rcb.data_len = sg_dma_len(sg);
416 cmd->rcb.data_ea = sg_dma_address(sg);
417 }
418
419 /* Copy the CDB from the scsi_cmnd passed in */
420 memcpy(cmd->rcb.cdb, scp->cmnd, sizeof(cmd->rcb.cdb));
421
422 /* Send the command */
423 rc = cxlflash_send_cmd(afu, cmd);
424 if (unlikely(rc)) {
425 cxlflash_cmd_checkin(cmd);
426 scsi_dma_unmap(scp);
427 }
428
429out:
430 return rc;
431}
432
433/**
434 * cxlflash_eh_device_reset_handler() - reset a single LUN
435 * @scp: SCSI command to send.
436 *
437 * Return:
438 * SUCCESS as defined in scsi/scsi.h
439 * FAILED as defined in scsi/scsi.h
440 */
441static int cxlflash_eh_device_reset_handler(struct scsi_cmnd *scp)
442{
443 int rc = SUCCESS;
444 struct Scsi_Host *host = scp->device->host;
445 struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)host->hostdata;
446 struct afu *afu = cfg->afu;
447 int rcr = 0;
448
449 pr_debug("%s: (scp=%p) %d/%d/%d/%llu "
450 "cdb=(%08X-%08X-%08X-%08X)\n", __func__, scp,
451 host->host_no, scp->device->channel,
452 scp->device->id, scp->device->lun,
453 get_unaligned_be32(&((u32 *)scp->cmnd)[0]),
454 get_unaligned_be32(&((u32 *)scp->cmnd)[1]),
455 get_unaligned_be32(&((u32 *)scp->cmnd)[2]),
456 get_unaligned_be32(&((u32 *)scp->cmnd)[3]));
457
458 rcr = send_tmf(afu, scp, TMF_LUN_RESET);
459 if (unlikely(rcr))
460 rc = FAILED;
461
462 pr_debug("%s: returning rc=%d\n", __func__, rc);
463 return rc;
464}
465
466/**
467 * cxlflash_eh_host_reset_handler() - reset the host adapter
468 * @scp: SCSI command from stack identifying host.
469 *
470 * Return:
471 * SUCCESS as defined in scsi/scsi.h
472 * FAILED as defined in scsi/scsi.h
473 */
474static int cxlflash_eh_host_reset_handler(struct scsi_cmnd *scp)
475{
476 int rc = SUCCESS;
477 int rcr = 0;
478 struct Scsi_Host *host = scp->device->host;
479 struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)host->hostdata;
480
481 pr_debug("%s: (scp=%p) %d/%d/%d/%llu "
482 "cdb=(%08X-%08X-%08X-%08X)\n", __func__, scp,
483 host->host_no, scp->device->channel,
484 scp->device->id, scp->device->lun,
485 get_unaligned_be32(&((u32 *)scp->cmnd)[0]),
486 get_unaligned_be32(&((u32 *)scp->cmnd)[1]),
487 get_unaligned_be32(&((u32 *)scp->cmnd)[2]),
488 get_unaligned_be32(&((u32 *)scp->cmnd)[3]));
489
490 rcr = cxlflash_afu_reset(cfg);
491 if (rcr == 0)
492 rc = SUCCESS;
493 else
494 rc = FAILED;
495
496 pr_debug("%s: returning rc=%d\n", __func__, rc);
497 return rc;
498}
499
500/**
501 * cxlflash_change_queue_depth() - change the queue depth for the device
502 * @sdev: SCSI device destined for queue depth change.
503 * @qdepth: Requested queue depth value to set.
504 *
505 * The requested queue depth is capped to the maximum supported value.
506 *
507 * Return: The actual queue depth set.
508 */
509static int cxlflash_change_queue_depth(struct scsi_device *sdev, int qdepth)
510{
511
512 if (qdepth > CXLFLASH_MAX_CMDS_PER_LUN)
513 qdepth = CXLFLASH_MAX_CMDS_PER_LUN;
514
515 scsi_change_queue_depth(sdev, qdepth);
516 return sdev->queue_depth;
517}
518
519/**
520 * cxlflash_show_port_status() - queries and presents the current port status
521 * @dev: Generic device associated with the host owning the port.
522 * @attr: Device attribute representing the port.
523 * @buf: Buffer of length PAGE_SIZE to report back port status in ASCII.
524 *
525 * Return: The size of the ASCII string returned in @buf.
526 */
527static ssize_t cxlflash_show_port_status(struct device *dev,
528 struct device_attribute *attr,
529 char *buf)
530{
531 struct Scsi_Host *shost = class_to_shost(dev);
532 struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)shost->hostdata;
533 struct afu *afu = cfg->afu;
534
535 char *disp_status;
536 int rc;
537 u32 port;
538 u64 status;
539 u64 *fc_regs;
540
541 rc = kstrtouint((attr->attr.name + 4), 10, &port);
542 if (rc || (port > NUM_FC_PORTS))
543 return 0;
544
545 fc_regs = &afu->afu_map->global.fc_regs[port][0];
546 status =
547 (readq_be(&fc_regs[FC_MTIP_STATUS / 8]) & FC_MTIP_STATUS_MASK);
548
549 if (status == FC_MTIP_STATUS_ONLINE)
550 disp_status = "online";
551 else if (status == FC_MTIP_STATUS_OFFLINE)
552 disp_status = "offline";
553 else
554 disp_status = "unknown";
555
556 return snprintf(buf, PAGE_SIZE, "%s\n", disp_status);
557}
558
559/**
560 * cxlflash_show_lun_mode() - presents the current LUN mode of the host
561 * @dev: Generic device associated with the host.
562 * @attr: Device attribute representing the lun mode.
563 * @buf: Buffer of length PAGE_SIZE to report back the LUN mode in ASCII.
564 *
565 * Return: The size of the ASCII string returned in @buf.
566 */
567static ssize_t cxlflash_show_lun_mode(struct device *dev,
568 struct device_attribute *attr, char *buf)
569{
570 struct Scsi_Host *shost = class_to_shost(dev);
571 struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)shost->hostdata;
572 struct afu *afu = cfg->afu;
573
574 return snprintf(buf, PAGE_SIZE, "%u\n", afu->internal_lun);
575}
576
577/**
578 * cxlflash_store_lun_mode() - sets the LUN mode of the host
579 * @dev: Generic device associated with the host.
580 * @attr: Device attribute representing the lun mode.
581 * @buf: Buffer of length PAGE_SIZE containing the LUN mode in ASCII.
582 * @count: Length of data resizing in @buf.
583 *
584 * The CXL Flash AFU supports a dummy LUN mode where the external
585 * links and storage are not required. Space on the FPGA is used
586 * to create 1 or 2 small LUNs which are presented to the system
587 * as if they were a normal storage device. This feature is useful
588 * during development and also provides manufacturing with a way
589 * to test the AFU without an actual device.
590 *
591 * 0 = external LUN[s] (default)
592 * 1 = internal LUN (1 x 64K, 512B blocks, id 0)
593 * 2 = internal LUN (1 x 64K, 4K blocks, id 0)
594 * 3 = internal LUN (2 x 32K, 512B blocks, ids 0,1)
595 * 4 = internal LUN (2 x 32K, 4K blocks, ids 0,1)
596 *
597 * Return: The size of the ASCII string returned in @buf.
598 */
599static ssize_t cxlflash_store_lun_mode(struct device *dev,
600 struct device_attribute *attr,
601 const char *buf, size_t count)
602{
603 struct Scsi_Host *shost = class_to_shost(dev);
604 struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)shost->hostdata;
605 struct afu *afu = cfg->afu;
606 int rc;
607 u32 lun_mode;
608
609 rc = kstrtouint(buf, 10, &lun_mode);
610 if (!rc && (lun_mode < 5) && (lun_mode != afu->internal_lun)) {
611 afu->internal_lun = lun_mode;
612 cxlflash_afu_reset(cfg);
613 scsi_scan_host(cfg->host);
614 }
615
616 return count;
617}
618
619/**
620 * cxlflash_show_dev_mode() - presents the current mode of the device
621 * @dev: Generic device associated with the device.
622 * @attr: Device attribute representing the device mode.
623 * @buf: Buffer of length PAGE_SIZE to report back the dev mode in ASCII.
624 *
625 * Return: The size of the ASCII string returned in @buf.
626 */
627static ssize_t cxlflash_show_dev_mode(struct device *dev,
628 struct device_attribute *attr, char *buf)
629{
630 struct scsi_device *sdev = to_scsi_device(dev);
631
632 return snprintf(buf, PAGE_SIZE, "%s\n",
633 sdev->hostdata ? "superpipe" : "legacy");
634}
635
636/**
637 * cxlflash_wait_for_pci_err_recovery() - wait for error recovery during probe
638 * @cxlflash: Internal structure associated with the host.
639 */
640static void cxlflash_wait_for_pci_err_recovery(struct cxlflash_cfg *cfg)
641{
642 struct pci_dev *pdev = cfg->dev;
643
644 if (pci_channel_offline(pdev))
645 wait_event_timeout(cfg->eeh_waitq,
646 !pci_channel_offline(pdev),
647 CXLFLASH_PCI_ERROR_RECOVERY_TIMEOUT);
648}
649
650/*
651 * Host attributes
652 */
653static DEVICE_ATTR(port0, S_IRUGO, cxlflash_show_port_status, NULL);
654static DEVICE_ATTR(port1, S_IRUGO, cxlflash_show_port_status, NULL);
655static DEVICE_ATTR(lun_mode, S_IRUGO | S_IWUSR, cxlflash_show_lun_mode,
656 cxlflash_store_lun_mode);
657
658static struct device_attribute *cxlflash_host_attrs[] = {
659 &dev_attr_port0,
660 &dev_attr_port1,
661 &dev_attr_lun_mode,
662 NULL
663};
664
665/*
666 * Device attributes
667 */
668static DEVICE_ATTR(mode, S_IRUGO, cxlflash_show_dev_mode, NULL);
669
670static struct device_attribute *cxlflash_dev_attrs[] = {
671 &dev_attr_mode,
672 NULL
673};
674
675/*
676 * Host template
677 */
678static struct scsi_host_template driver_template = {
679 .module = THIS_MODULE,
680 .name = CXLFLASH_ADAPTER_NAME,
681 .info = cxlflash_driver_info,
682 .proc_name = CXLFLASH_NAME,
683 .queuecommand = cxlflash_queuecommand,
684 .eh_device_reset_handler = cxlflash_eh_device_reset_handler,
685 .eh_host_reset_handler = cxlflash_eh_host_reset_handler,
686 .change_queue_depth = cxlflash_change_queue_depth,
687 .cmd_per_lun = 16,
688 .can_queue = CXLFLASH_MAX_CMDS,
689 .this_id = -1,
690 .sg_tablesize = SG_NONE, /* No scatter gather support. */
691 .max_sectors = CXLFLASH_MAX_SECTORS,
692 .use_clustering = ENABLE_CLUSTERING,
693 .shost_attrs = cxlflash_host_attrs,
694 .sdev_attrs = cxlflash_dev_attrs,
695};
696
697/*
698 * Device dependent values
699 */
700static struct dev_dependent_vals dev_corsa_vals = { CXLFLASH_MAX_SECTORS };
701
702/*
703 * PCI device binding table
704 */
705static struct pci_device_id cxlflash_pci_table[] = {
706 {PCI_VENDOR_ID_IBM, PCI_DEVICE_ID_IBM_CORSA,
707 PCI_ANY_ID, PCI_ANY_ID, 0, 0, (kernel_ulong_t)&dev_corsa_vals},
708 {}
709};
710
711MODULE_DEVICE_TABLE(pci, cxlflash_pci_table);
712
713/**
714 * free_mem() - free memory associated with the AFU
715 * @cxlflash: Internal structure associated with the host.
716 */
717static void free_mem(struct cxlflash_cfg *cfg)
718{
719 int i;
720 char *buf = NULL;
721 struct afu *afu = cfg->afu;
722
723 if (cfg->afu) {
724 for (i = 0; i < CXLFLASH_NUM_CMDS; i++) {
725 buf = afu->cmd[i].buf;
726 if (!((u64)buf & (PAGE_SIZE - 1)))
727 free_page((ulong)buf);
728 }
729
730 free_pages((ulong)afu, get_order(sizeof(struct afu)));
731 cfg->afu = NULL;
732 }
733}
734
735/**
736 * stop_afu() - stops the AFU command timers and unmaps the MMIO space
737 * @cxlflash: Internal structure associated with the host.
738 *
739 * Safe to call with AFU in a partially allocated/initialized state.
740 */
741static void stop_afu(struct cxlflash_cfg *cfg)
742{
743 int i;
744 struct afu *afu = cfg->afu;
745
746 if (likely(afu)) {
747 for (i = 0; i < CXLFLASH_NUM_CMDS; i++)
748 complete(&afu->cmd[i].cevent);
749
750 if (likely(afu->afu_map)) {
751 cxl_psa_unmap((void *)afu->afu_map);
752 afu->afu_map = NULL;
753 }
754 }
755}
756
757/**
758 * term_mc() - terminates the master context
759 * @cxlflash: Internal structure associated with the host.
760 * @level: Depth of allocation, where to begin waterfall tear down.
761 *
762 * Safe to call with AFU/MC in partially allocated/initialized state.
763 */
764static void term_mc(struct cxlflash_cfg *cfg, enum undo_level level)
765{
766 int rc = 0;
767 struct afu *afu = cfg->afu;
768
769 if (!afu || !cfg->mcctx) {
770 pr_err("%s: returning from term_mc with NULL afu or MC\n",
771 __func__);
772 return;
773 }
774
775 switch (level) {
776 case UNDO_START:
777 rc = cxl_stop_context(cfg->mcctx);
778 BUG_ON(rc);
779 case UNMAP_THREE:
780 cxl_unmap_afu_irq(cfg->mcctx, 3, afu);
781 case UNMAP_TWO:
782 cxl_unmap_afu_irq(cfg->mcctx, 2, afu);
783 case UNMAP_ONE:
784 cxl_unmap_afu_irq(cfg->mcctx, 1, afu);
785 case FREE_IRQ:
786 cxl_free_afu_irqs(cfg->mcctx);
787 case RELEASE_CONTEXT:
788 cfg->mcctx = NULL;
789 }
790}
791
792/**
793 * term_afu() - terminates the AFU
794 * @cxlflash: Internal structure associated with the host.
795 *
796 * Safe to call with AFU/MC in partially allocated/initialized state.
797 */
798static void term_afu(struct cxlflash_cfg *cfg)
799{
800 term_mc(cfg, UNDO_START);
801
802 if (cfg->afu)
803 stop_afu(cfg);
804
805 pr_debug("%s: returning\n", __func__);
806}
807
808/**
809 * cxlflash_remove() - PCI entry point to tear down host
810 * @pdev: PCI device associated with the host.
811 *
812 * Safe to use as a cleanup in partially allocated/initialized state.
813 */
814static void cxlflash_remove(struct pci_dev *pdev)
815{
816 struct cxlflash_cfg *cfg = pci_get_drvdata(pdev);
817 ulong lock_flags;
818
819 /* If a Task Management Function is active, wait for it to complete
820 * before continuing with remove.
821 */
822 spin_lock_irqsave(&cfg->tmf_waitq.lock, lock_flags);
823 if (cfg->tmf_active)
824 wait_event_interruptible_locked_irq(cfg->tmf_waitq,
825 !cfg->tmf_active);
826 spin_unlock_irqrestore(&cfg->tmf_waitq.lock, lock_flags);
827
828 switch (cfg->init_state) {
829 case INIT_STATE_SCSI:
830 scsi_remove_host(cfg->host);
831 scsi_host_put(cfg->host);
832 /* Fall through */
833 case INIT_STATE_AFU:
834 term_afu(cfg);
835 case INIT_STATE_PCI:
836 pci_release_regions(cfg->dev);
837 pci_disable_device(pdev);
838 case INIT_STATE_NONE:
839 flush_work(&cfg->work_q);
840 free_mem(cfg);
841 break;
842 }
843
844 pr_debug("%s: returning\n", __func__);
845}
846
847/**
848 * alloc_mem() - allocates the AFU and its command pool
849 * @cxlflash: Internal structure associated with the host.
850 *
851 * A partially allocated state remains on failure.
852 *
853 * Return:
854 * 0 on success
855 * -ENOMEM on failure to allocate memory
856 */
857static int alloc_mem(struct cxlflash_cfg *cfg)
858{
859 int rc = 0;
860 int i;
861 char *buf = NULL;
862
863 /* This allocation is about 12K, i.e. only 1 64k page
864 * and upto 4 4k pages
865 */
866 cfg->afu = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
867 get_order(sizeof(struct afu)));
868 if (unlikely(!cfg->afu)) {
869 pr_err("%s: cannot get %d free pages\n",
870 __func__, get_order(sizeof(struct afu)));
871 rc = -ENOMEM;
872 goto out;
873 }
874 cfg->afu->parent = cfg;
875 cfg->afu->afu_map = NULL;
876
877 for (i = 0; i < CXLFLASH_NUM_CMDS; buf += CMD_BUFSIZE, i++) {
878 if (!((u64)buf & (PAGE_SIZE - 1))) {
879 buf = (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
880 if (unlikely(!buf)) {
881 pr_err("%s: Allocate command buffers fail!\n",
882 __func__);
883 rc = -ENOMEM;
884 free_mem(cfg);
885 goto out;
886 }
887 }
888
889 cfg->afu->cmd[i].buf = buf;
890 atomic_set(&cfg->afu->cmd[i].free, 1);
891 cfg->afu->cmd[i].slot = i;
892 }
893
894out:
895 return rc;
896}
897
898/**
899 * init_pci() - initializes the host as a PCI device
900 * @cxlflash: Internal structure associated with the host.
901 *
902 * Return:
903 * 0 on success
904 * -EIO on unable to communicate with device
905 * A return code from the PCI sub-routines
906 */
907static int init_pci(struct cxlflash_cfg *cfg)
908{
909 struct pci_dev *pdev = cfg->dev;
910 int rc = 0;
911
912 cfg->cxlflash_regs_pci = pci_resource_start(pdev, 0);
913 rc = pci_request_regions(pdev, CXLFLASH_NAME);
914 if (rc < 0) {
915 dev_err(&pdev->dev,
916 "%s: Couldn't register memory range of registers\n",
917 __func__);
918 goto out;
919 }
920
921 rc = pci_enable_device(pdev);
922 if (rc || pci_channel_offline(pdev)) {
923 if (pci_channel_offline(pdev)) {
924 cxlflash_wait_for_pci_err_recovery(cfg);
925 rc = pci_enable_device(pdev);
926 }
927
928 if (rc) {
929 dev_err(&pdev->dev, "%s: Cannot enable adapter\n",
930 __func__);
931 cxlflash_wait_for_pci_err_recovery(cfg);
932 goto out_release_regions;
933 }
934 }
935
936 rc = pci_set_dma_mask(pdev, DMA_BIT_MASK(64));
937 if (rc < 0) {
938 dev_dbg(&pdev->dev, "%s: Failed to set 64 bit PCI DMA mask\n",
939 __func__);
940 rc = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
941 }
942
943 if (rc < 0) {
944 dev_err(&pdev->dev, "%s: Failed to set PCI DMA mask\n",
945 __func__);
946 goto out_disable;
947 }
948
949 pci_set_master(pdev);
950
951 if (pci_channel_offline(pdev)) {
952 cxlflash_wait_for_pci_err_recovery(cfg);
953 if (pci_channel_offline(pdev)) {
954 rc = -EIO;
955 goto out_msi_disable;
956 }
957 }
958
959 rc = pci_save_state(pdev);
960
961 if (rc != PCIBIOS_SUCCESSFUL) {
962 dev_err(&pdev->dev, "%s: Failed to save PCI config space\n",
963 __func__);
964 rc = -EIO;
965 goto cleanup_nolog;
966 }
967
968out:
969 pr_debug("%s: returning rc=%d\n", __func__, rc);
970 return rc;
971
972cleanup_nolog:
973out_msi_disable:
974 cxlflash_wait_for_pci_err_recovery(cfg);
975out_disable:
976 pci_disable_device(pdev);
977out_release_regions:
978 pci_release_regions(pdev);
979 goto out;
980
981}
982
983/**
984 * init_scsi() - adds the host to the SCSI stack and kicks off host scan
985 * @cxlflash: Internal structure associated with the host.
986 *
987 * Return:
988 * 0 on success
989 * A return code from adding the host
990 */
991static int init_scsi(struct cxlflash_cfg *cfg)
992{
993 struct pci_dev *pdev = cfg->dev;
994 int rc = 0;
995
996 rc = scsi_add_host(cfg->host, &pdev->dev);
997 if (rc) {
998 dev_err(&pdev->dev, "%s: scsi_add_host failed (rc=%d)\n",
999 __func__, rc);
1000 goto out;
1001 }
1002
1003 scsi_scan_host(cfg->host);
1004
1005out:
1006 pr_debug("%s: returning rc=%d\n", __func__, rc);
1007 return rc;
1008}
1009
1010/**
1011 * set_port_online() - transitions the specified host FC port to online state
1012 * @fc_regs: Top of MMIO region defined for specified port.
1013 *
1014 * The provided MMIO region must be mapped prior to call. Online state means
1015 * that the FC link layer has synced, completed the handshaking process, and
1016 * is ready for login to start.
1017 */
1018static void set_port_online(u64 *fc_regs)
1019{
1020 u64 cmdcfg;
1021
1022 cmdcfg = readq_be(&fc_regs[FC_MTIP_CMDCONFIG / 8]);
1023 cmdcfg &= (~FC_MTIP_CMDCONFIG_OFFLINE); /* clear OFF_LINE */
1024 cmdcfg |= (FC_MTIP_CMDCONFIG_ONLINE); /* set ON_LINE */
1025 writeq_be(cmdcfg, &fc_regs[FC_MTIP_CMDCONFIG / 8]);
1026}
1027
1028/**
1029 * set_port_offline() - transitions the specified host FC port to offline state
1030 * @fc_regs: Top of MMIO region defined for specified port.
1031 *
1032 * The provided MMIO region must be mapped prior to call.
1033 */
1034static void set_port_offline(u64 *fc_regs)
1035{
1036 u64 cmdcfg;
1037
1038 cmdcfg = readq_be(&fc_regs[FC_MTIP_CMDCONFIG / 8]);
1039 cmdcfg &= (~FC_MTIP_CMDCONFIG_ONLINE); /* clear ON_LINE */
1040 cmdcfg |= (FC_MTIP_CMDCONFIG_OFFLINE); /* set OFF_LINE */
1041 writeq_be(cmdcfg, &fc_regs[FC_MTIP_CMDCONFIG / 8]);
1042}
1043
1044/**
1045 * wait_port_online() - waits for the specified host FC port come online
1046 * @fc_regs: Top of MMIO region defined for specified port.
1047 * @delay_us: Number of microseconds to delay between reading port status.
1048 * @nretry: Number of cycles to retry reading port status.
1049 *
1050 * The provided MMIO region must be mapped prior to call. This will timeout
1051 * when the cable is not plugged in.
1052 *
1053 * Return:
1054 * TRUE (1) when the specified port is online
1055 * FALSE (0) when the specified port fails to come online after timeout
1056 * -EINVAL when @delay_us is less than 1000
1057 */
1058static int wait_port_online(u64 *fc_regs, u32 delay_us, u32 nretry)
1059{
1060 u64 status;
1061
1062 if (delay_us < 1000) {
1063 pr_err("%s: invalid delay specified %d\n", __func__, delay_us);
1064 return -EINVAL;
1065 }
1066
1067 do {
1068 msleep(delay_us / 1000);
1069 status = readq_be(&fc_regs[FC_MTIP_STATUS / 8]);
1070 } while ((status & FC_MTIP_STATUS_MASK) != FC_MTIP_STATUS_ONLINE &&
1071 nretry--);
1072
1073 return ((status & FC_MTIP_STATUS_MASK) == FC_MTIP_STATUS_ONLINE);
1074}
1075
1076/**
1077 * wait_port_offline() - waits for the specified host FC port go offline
1078 * @fc_regs: Top of MMIO region defined for specified port.
1079 * @delay_us: Number of microseconds to delay between reading port status.
1080 * @nretry: Number of cycles to retry reading port status.
1081 *
1082 * The provided MMIO region must be mapped prior to call.
1083 *
1084 * Return:
1085 * TRUE (1) when the specified port is offline
1086 * FALSE (0) when the specified port fails to go offline after timeout
1087 * -EINVAL when @delay_us is less than 1000
1088 */
1089static int wait_port_offline(u64 *fc_regs, u32 delay_us, u32 nretry)
1090{
1091 u64 status;
1092
1093 if (delay_us < 1000) {
1094 pr_err("%s: invalid delay specified %d\n", __func__, delay_us);
1095 return -EINVAL;
1096 }
1097
1098 do {
1099 msleep(delay_us / 1000);
1100 status = readq_be(&fc_regs[FC_MTIP_STATUS / 8]);
1101 } while ((status & FC_MTIP_STATUS_MASK) != FC_MTIP_STATUS_OFFLINE &&
1102 nretry--);
1103
1104 return ((status & FC_MTIP_STATUS_MASK) == FC_MTIP_STATUS_OFFLINE);
1105}
1106
1107/**
1108 * afu_set_wwpn() - configures the WWPN for the specified host FC port
1109 * @afu: AFU associated with the host that owns the specified FC port.
1110 * @port: Port number being configured.
1111 * @fc_regs: Top of MMIO region defined for specified port.
1112 * @wwpn: The world-wide-port-number previously discovered for port.
1113 *
1114 * The provided MMIO region must be mapped prior to call. As part of the
1115 * sequence to configure the WWPN, the port is toggled offline and then back
1116 * online. This toggling action can cause this routine to delay up to a few
1117 * seconds. When configured to use the internal LUN feature of the AFU, a
1118 * failure to come online is overridden.
1119 *
1120 * Return:
1121 * 0 when the WWPN is successfully written and the port comes back online
1122 * -1 when the port fails to go offline or come back up online
1123 */
1124static int afu_set_wwpn(struct afu *afu, int port, u64 *fc_regs, u64 wwpn)
1125{
1126 int ret = 0;
1127
1128 set_port_offline(fc_regs);
1129
1130 if (!wait_port_offline(fc_regs, FC_PORT_STATUS_RETRY_INTERVAL_US,
1131 FC_PORT_STATUS_RETRY_CNT)) {
1132 pr_debug("%s: wait on port %d to go offline timed out\n",
1133 __func__, port);
1134 ret = -1; /* but continue on to leave the port back online */
1135 }
1136
1137 if (ret == 0)
1138 writeq_be(wwpn, &fc_regs[FC_PNAME / 8]);
1139
1140 set_port_online(fc_regs);
1141
1142 if (!wait_port_online(fc_regs, FC_PORT_STATUS_RETRY_INTERVAL_US,
1143 FC_PORT_STATUS_RETRY_CNT)) {
1144 pr_debug("%s: wait on port %d to go online timed out\n",
1145 __func__, port);
1146 ret = -1;
1147
1148 /*
1149 * Override for internal lun!!!
1150 */
1151 if (afu->internal_lun) {
1152 pr_debug("%s: Overriding port %d online timeout!!!\n",
1153 __func__, port);
1154 ret = 0;
1155 }
1156 }
1157
1158 pr_debug("%s: returning rc=%d\n", __func__, ret);
1159
1160 return ret;
1161}
1162
1163/**
1164 * afu_link_reset() - resets the specified host FC port
1165 * @afu: AFU associated with the host that owns the specified FC port.
1166 * @port: Port number being configured.
1167 * @fc_regs: Top of MMIO region defined for specified port.
1168 *
1169 * The provided MMIO region must be mapped prior to call. The sequence to
1170 * reset the port involves toggling it offline and then back online. This
1171 * action can cause this routine to delay up to a few seconds. An effort
1172 * is made to maintain link with the device by switching to host to use
1173 * the alternate port exclusively while the reset takes place.
1174 * failure to come online is overridden.
1175 */
1176static void afu_link_reset(struct afu *afu, int port, u64 *fc_regs)
1177{
1178 u64 port_sel;
1179
1180 /* first switch the AFU to the other links, if any */
1181 port_sel = readq_be(&afu->afu_map->global.regs.afu_port_sel);
1182 port_sel &= ~(1 << port);
1183 writeq_be(port_sel, &afu->afu_map->global.regs.afu_port_sel);
1184 cxlflash_afu_sync(afu, 0, 0, AFU_GSYNC);
1185
1186 set_port_offline(fc_regs);
1187 if (!wait_port_offline(fc_regs, FC_PORT_STATUS_RETRY_INTERVAL_US,
1188 FC_PORT_STATUS_RETRY_CNT))
1189 pr_err("%s: wait on port %d to go offline timed out\n",
1190 __func__, port);
1191
1192 set_port_online(fc_regs);
1193 if (!wait_port_online(fc_regs, FC_PORT_STATUS_RETRY_INTERVAL_US,
1194 FC_PORT_STATUS_RETRY_CNT))
1195 pr_err("%s: wait on port %d to go online timed out\n",
1196 __func__, port);
1197
1198 /* switch back to include this port */
1199 port_sel |= (1 << port);
1200 writeq_be(port_sel, &afu->afu_map->global.regs.afu_port_sel);
1201 cxlflash_afu_sync(afu, 0, 0, AFU_GSYNC);
1202
1203 pr_debug("%s: returning port_sel=%lld\n", __func__, port_sel);
1204}
1205
1206/*
1207 * Asynchronous interrupt information table
1208 */
1209static const struct asyc_intr_info ainfo[] = {
1210 {SISL_ASTATUS_FC0_OTHER, "other error", 0, CLR_FC_ERROR | LINK_RESET},
1211 {SISL_ASTATUS_FC0_LOGO, "target initiated LOGO", 0, 0},
1212 {SISL_ASTATUS_FC0_CRC_T, "CRC threshold exceeded", 0, LINK_RESET},
1213 {SISL_ASTATUS_FC0_LOGI_R, "login timed out, retrying", 0, 0},
1214 {SISL_ASTATUS_FC0_LOGI_F, "login failed", 0, CLR_FC_ERROR},
1215 {SISL_ASTATUS_FC0_LOGI_S, "login succeeded", 0, 0},
1216 {SISL_ASTATUS_FC0_LINK_DN, "link down", 0, 0},
1217 {SISL_ASTATUS_FC0_LINK_UP, "link up", 0, 0},
1218 {SISL_ASTATUS_FC1_OTHER, "other error", 1, CLR_FC_ERROR | LINK_RESET},
1219 {SISL_ASTATUS_FC1_LOGO, "target initiated LOGO", 1, 0},
1220 {SISL_ASTATUS_FC1_CRC_T, "CRC threshold exceeded", 1, LINK_RESET},
1221 {SISL_ASTATUS_FC1_LOGI_R, "login timed out, retrying", 1, 0},
1222 {SISL_ASTATUS_FC1_LOGI_F, "login failed", 1, CLR_FC_ERROR},
1223 {SISL_ASTATUS_FC1_LOGI_S, "login succeeded", 1, 0},
1224 {SISL_ASTATUS_FC1_LINK_DN, "link down", 1, 0},
1225 {SISL_ASTATUS_FC1_LINK_UP, "link up", 1, 0},
1226 {0x0, "", 0, 0} /* terminator */
1227};
1228
1229/**
1230 * find_ainfo() - locates and returns asynchronous interrupt information
1231 * @status: Status code set by AFU on error.
1232 *
1233 * Return: The located information or NULL when the status code is invalid.
1234 */
1235static const struct asyc_intr_info *find_ainfo(u64 status)
1236{
1237 const struct asyc_intr_info *info;
1238
1239 for (info = &ainfo[0]; info->status; info++)
1240 if (info->status == status)
1241 return info;
1242
1243 return NULL;
1244}
1245
1246/**
1247 * afu_err_intr_init() - clears and initializes the AFU for error interrupts
1248 * @afu: AFU associated with the host.
1249 */
1250static void afu_err_intr_init(struct afu *afu)
1251{
1252 int i;
1253 u64 reg;
1254
1255 /* global async interrupts: AFU clears afu_ctrl on context exit
1256 * if async interrupts were sent to that context. This prevents
1257 * the AFU form sending further async interrupts when
1258 * there is
1259 * nobody to receive them.
1260 */
1261
1262 /* mask all */
1263 writeq_be(-1ULL, &afu->afu_map->global.regs.aintr_mask);
1264 /* set LISN# to send and point to master context */
1265 reg = ((u64) (((afu->ctx_hndl << 8) | SISL_MSI_ASYNC_ERROR)) << 40);
1266
1267 if (afu->internal_lun)
1268 reg |= 1; /* Bit 63 indicates local lun */
1269 writeq_be(reg, &afu->afu_map->global.regs.afu_ctrl);
1270 /* clear all */
1271 writeq_be(-1ULL, &afu->afu_map->global.regs.aintr_clear);
1272 /* unmask bits that are of interest */
1273 /* note: afu can send an interrupt after this step */
1274 writeq_be(SISL_ASTATUS_MASK, &afu->afu_map->global.regs.aintr_mask);
1275 /* clear again in case a bit came on after previous clear but before */
1276 /* unmask */
1277 writeq_be(-1ULL, &afu->afu_map->global.regs.aintr_clear);
1278
1279 /* Clear/Set internal lun bits */
1280 reg = readq_be(&afu->afu_map->global.fc_regs[0][FC_CONFIG2 / 8]);
1281 reg &= SISL_FC_INTERNAL_MASK;
1282 if (afu->internal_lun)
1283 reg |= ((u64)(afu->internal_lun - 1) << SISL_FC_INTERNAL_SHIFT);
1284 writeq_be(reg, &afu->afu_map->global.fc_regs[0][FC_CONFIG2 / 8]);
1285
1286 /* now clear FC errors */
1287 for (i = 0; i < NUM_FC_PORTS; i++) {
1288 writeq_be(0xFFFFFFFFU,
1289 &afu->afu_map->global.fc_regs[i][FC_ERROR / 8]);
1290 writeq_be(0, &afu->afu_map->global.fc_regs[i][FC_ERRCAP / 8]);
1291 }
1292
1293 /* sync interrupts for master's IOARRIN write */
1294 /* note that unlike asyncs, there can be no pending sync interrupts */
1295 /* at this time (this is a fresh context and master has not written */
1296 /* IOARRIN yet), so there is nothing to clear. */
1297
1298 /* set LISN#, it is always sent to the context that wrote IOARRIN */
1299 writeq_be(SISL_MSI_SYNC_ERROR, &afu->host_map->ctx_ctrl);
1300 writeq_be(SISL_ISTATUS_MASK, &afu->host_map->intr_mask);
1301}
1302
1303/**
1304 * cxlflash_sync_err_irq() - interrupt handler for synchronous errors
1305 * @irq: Interrupt number.
1306 * @data: Private data provided at interrupt registration, the AFU.
1307 *
1308 * Return: Always return IRQ_HANDLED.
1309 */
1310static irqreturn_t cxlflash_sync_err_irq(int irq, void *data)
1311{
1312 struct afu *afu = (struct afu *)data;
1313 u64 reg;
1314 u64 reg_unmasked;
1315
1316 reg = readq_be(&afu->host_map->intr_status);
1317 reg_unmasked = (reg & SISL_ISTATUS_UNMASK);
1318
1319 if (reg_unmasked == 0UL) {
1320 pr_err("%s: %llX: spurious interrupt, intr_status %016llX\n",
1321 __func__, (u64)afu, reg);
1322 goto cxlflash_sync_err_irq_exit;
1323 }
1324
1325 pr_err("%s: %llX: unexpected interrupt, intr_status %016llX\n",
1326 __func__, (u64)afu, reg);
1327
1328 writeq_be(reg_unmasked, &afu->host_map->intr_clear);
1329
1330cxlflash_sync_err_irq_exit:
1331 pr_debug("%s: returning rc=%d\n", __func__, IRQ_HANDLED);
1332 return IRQ_HANDLED;
1333}
1334
1335/**
1336 * cxlflash_rrq_irq() - interrupt handler for read-response queue (normal path)
1337 * @irq: Interrupt number.
1338 * @data: Private data provided at interrupt registration, the AFU.
1339 *
1340 * Return: Always return IRQ_HANDLED.
1341 */
1342static irqreturn_t cxlflash_rrq_irq(int irq, void *data)
1343{
1344 struct afu *afu = (struct afu *)data;
1345 struct afu_cmd *cmd;
1346 bool toggle = afu->toggle;
1347 u64 entry,
1348 *hrrq_start = afu->hrrq_start,
1349 *hrrq_end = afu->hrrq_end,
1350 *hrrq_curr = afu->hrrq_curr;
1351
1352 /* Process however many RRQ entries that are ready */
1353 while (true) {
1354 entry = *hrrq_curr;
1355
1356 if ((entry & SISL_RESP_HANDLE_T_BIT) != toggle)
1357 break;
1358
1359 cmd = (struct afu_cmd *)(entry & ~SISL_RESP_HANDLE_T_BIT);
1360 cmd_complete(cmd);
1361
1362 /* Advance to next entry or wrap and flip the toggle bit */
1363 if (hrrq_curr < hrrq_end)
1364 hrrq_curr++;
1365 else {
1366 hrrq_curr = hrrq_start;
1367 toggle ^= SISL_RESP_HANDLE_T_BIT;
1368 }
1369 }
1370
1371 afu->hrrq_curr = hrrq_curr;
1372 afu->toggle = toggle;
1373
1374 return IRQ_HANDLED;
1375}
1376
1377/**
1378 * cxlflash_async_err_irq() - interrupt handler for asynchronous errors
1379 * @irq: Interrupt number.
1380 * @data: Private data provided at interrupt registration, the AFU.
1381 *
1382 * Return: Always return IRQ_HANDLED.
1383 */
1384static irqreturn_t cxlflash_async_err_irq(int irq, void *data)
1385{
1386 struct afu *afu = (struct afu *)data;
1387 struct cxlflash_cfg *cfg;
1388 u64 reg_unmasked;
1389 const struct asyc_intr_info *info;
1390 struct sisl_global_map *global = &afu->afu_map->global;
1391 u64 reg;
1392 u8 port;
1393 int i;
1394
1395 cfg = afu->parent;
1396
1397 reg = readq_be(&global->regs.aintr_status);
1398 reg_unmasked = (reg & SISL_ASTATUS_UNMASK);
1399
1400 if (reg_unmasked == 0) {
1401 pr_err("%s: spurious interrupt, aintr_status 0x%016llX\n",
1402 __func__, reg);
1403 goto out;
1404 }
1405
1406 /* it is OK to clear AFU status before FC_ERROR */
1407 writeq_be(reg_unmasked, &global->regs.aintr_clear);
1408
1409 /* check each bit that is on */
1410 for (i = 0; reg_unmasked; i++, reg_unmasked = (reg_unmasked >> 1)) {
1411 info = find_ainfo(1ULL << i);
1412 if ((reg_unmasked & 0x1) || !info)
1413 continue;
1414
1415 port = info->port;
1416
1417 pr_err("%s: FC Port %d -> %s, fc_status 0x%08llX\n",
1418 __func__, port, info->desc,
1419 readq_be(&global->fc_regs[port][FC_STATUS / 8]));
1420
1421 /*
1422 * do link reset first, some OTHER errors will set FC_ERROR
1423 * again if cleared before or w/o a reset
1424 */
1425 if (info->action & LINK_RESET) {
1426 pr_err("%s: FC Port %d: resetting link\n",
1427 __func__, port);
1428 cfg->lr_state = LINK_RESET_REQUIRED;
1429 cfg->lr_port = port;
1430 schedule_work(&cfg->work_q);
1431 }
1432
1433 if (info->action & CLR_FC_ERROR) {
1434 reg = readq_be(&global->fc_regs[port][FC_ERROR / 8]);
1435
1436 /*
1437 * since all errors are unmasked, FC_ERROR and FC_ERRCAP
1438 * should be the same and tracing one is sufficient.
1439 */
1440
1441 pr_err("%s: fc %d: clearing fc_error 0x%08llX\n",
1442 __func__, port, reg);
1443
1444 writeq_be(reg, &global->fc_regs[port][FC_ERROR / 8]);
1445 writeq_be(0, &global->fc_regs[port][FC_ERRCAP / 8]);
1446 }
1447 }
1448
1449out:
1450 pr_debug("%s: returning rc=%d, afu=%p\n", __func__, IRQ_HANDLED, afu);
1451 return IRQ_HANDLED;
1452}
1453
1454/**
1455 * start_context() - starts the master context
1456 * @cxlflash: Internal structure associated with the host.
1457 *
1458 * Return: A success or failure value from CXL services.
1459 */
1460static int start_context(struct cxlflash_cfg *cfg)
1461{
1462 int rc = 0;
1463
1464 rc = cxl_start_context(cfg->mcctx,
1465 cfg->afu->work.work_element_descriptor,
1466 NULL);
1467
1468 pr_debug("%s: returning rc=%d\n", __func__, rc);
1469 return rc;
1470}
1471
1472/**
1473 * read_vpd() - obtains the WWPNs from VPD
1474 * @cxlflash: Internal structure associated with the host.
1475 * @wwpn: Array of size NUM_FC_PORTS to pass back WWPNs
1476 *
1477 * Return:
1478 * 0 on success
1479 * -ENODEV when VPD or WWPN keywords not found
1480 */
1481static int read_vpd(struct cxlflash_cfg *cfg, u64 wwpn[])
1482{
1483 struct pci_dev *dev = cfg->parent_dev;
1484 int rc = 0;
1485 int ro_start, ro_size, i, j, k;
1486 ssize_t vpd_size;
1487 char vpd_data[CXLFLASH_VPD_LEN];
1488 char tmp_buf[WWPN_BUF_LEN] = { 0 };
1489 char *wwpn_vpd_tags[NUM_FC_PORTS] = { "V5", "V6" };
1490
1491 /* Get the VPD data from the device */
1492 vpd_size = pci_read_vpd(dev, 0, sizeof(vpd_data), vpd_data);
1493 if (unlikely(vpd_size <= 0)) {
1494 pr_err("%s: Unable to read VPD (size = %ld)\n",
1495 __func__, vpd_size);
1496 rc = -ENODEV;
1497 goto out;
1498 }
1499
1500 /* Get the read only section offset */
1501 ro_start = pci_vpd_find_tag(vpd_data, 0, vpd_size,
1502 PCI_VPD_LRDT_RO_DATA);
1503 if (unlikely(ro_start < 0)) {
1504 pr_err("%s: VPD Read-only data not found\n", __func__);
1505 rc = -ENODEV;
1506 goto out;
1507 }
1508
1509 /* Get the read only section size, cap when extends beyond read VPD */
1510 ro_size = pci_vpd_lrdt_size(&vpd_data[ro_start]);
1511 j = ro_size;
1512 i = ro_start + PCI_VPD_LRDT_TAG_SIZE;
1513 if (unlikely((i + j) > vpd_size)) {
1514 pr_debug("%s: Might need to read more VPD (%d > %ld)\n",
1515 __func__, (i + j), vpd_size);
1516 ro_size = vpd_size - i;
1517 }
1518
1519 /*
1520 * Find the offset of the WWPN tag within the read only
1521 * VPD data and validate the found field (partials are
1522 * no good to us). Convert the ASCII data to an integer
1523 * value. Note that we must copy to a temporary buffer
1524 * because the conversion service requires that the ASCII
1525 * string be terminated.
1526 */
1527 for (k = 0; k < NUM_FC_PORTS; k++) {
1528 j = ro_size;
1529 i = ro_start + PCI_VPD_LRDT_TAG_SIZE;
1530
1531 i = pci_vpd_find_info_keyword(vpd_data, i, j, wwpn_vpd_tags[k]);
1532 if (unlikely(i < 0)) {
1533 pr_err("%s: Port %d WWPN not found in VPD\n",
1534 __func__, k);
1535 rc = -ENODEV;
1536 goto out;
1537 }
1538
1539 j = pci_vpd_info_field_size(&vpd_data[i]);
1540 i += PCI_VPD_INFO_FLD_HDR_SIZE;
1541 if (unlikely((i + j > vpd_size) || (j != WWPN_LEN))) {
1542 pr_err("%s: Port %d WWPN incomplete or VPD corrupt\n",
1543 __func__, k);
1544 rc = -ENODEV;
1545 goto out;
1546 }
1547
1548 memcpy(tmp_buf, &vpd_data[i], WWPN_LEN);
1549 rc = kstrtoul(tmp_buf, WWPN_LEN, (ulong *)&wwpn[k]);
1550 if (unlikely(rc)) {
1551 pr_err("%s: Fail to convert port %d WWPN to integer\n",
1552 __func__, k);
1553 rc = -ENODEV;
1554 goto out;
1555 }
1556 }
1557
1558out:
1559 pr_debug("%s: returning rc=%d\n", __func__, rc);
1560 return rc;
1561}
1562
1563/**
1564 * cxlflash_context_reset() - timeout handler for AFU commands
1565 * @cmd: AFU command that timed out.
1566 *
1567 * Sends a reset to the AFU.
1568 */
1569void cxlflash_context_reset(struct afu_cmd *cmd)
1570{
1571 int nretry = 0;
1572 u64 rrin = 0x1;
1573 u64 room = 0;
1574 struct afu *afu = cmd->parent;
1575 ulong lock_flags;
1576
1577 pr_debug("%s: cmd=%p\n", __func__, cmd);
1578
1579 spin_lock_irqsave(&cmd->slock, lock_flags);
1580
1581 /* Already completed? */
1582 if (cmd->sa.host_use_b[0] & B_DONE) {
1583 spin_unlock_irqrestore(&cmd->slock, lock_flags);
1584 return;
1585 }
1586
1587 cmd->sa.host_use_b[0] |= (B_DONE | B_ERROR | B_TIMEOUT);
1588 spin_unlock_irqrestore(&cmd->slock, lock_flags);
1589
1590 /*
1591 * We really want to send this reset at all costs, so spread
1592 * out wait time on successive retries for available room.
1593 */
1594 do {
1595 room = readq_be(&afu->host_map->cmd_room);
1596 atomic64_set(&afu->room, room);
1597 if (room)
1598 goto write_rrin;
1599 udelay(nretry);
1600 } while (nretry++ < MC_ROOM_RETRY_CNT);
1601
1602 pr_err("%s: no cmd_room to send reset\n", __func__);
1603 return;
1604
1605write_rrin:
1606 nretry = 0;
1607 writeq_be(rrin, &afu->host_map->ioarrin);
1608 do {
1609 rrin = readq_be(&afu->host_map->ioarrin);
1610 if (rrin != 0x1)
1611 break;
1612 /* Double delay each time */
1613 udelay(2 ^ nretry);
1614 } while (nretry++ < MC_ROOM_RETRY_CNT);
1615}
1616
1617/**
1618 * init_pcr() - initialize the provisioning and control registers
1619 * @cxlflash: Internal structure associated with the host.
1620 *
1621 * Also sets up fast access to the mapped registers and initializes AFU
1622 * command fields that never change.
1623 */
1624void init_pcr(struct cxlflash_cfg *cfg)
1625{
1626 struct afu *afu = cfg->afu;
1627 struct sisl_ctrl_map *ctrl_map;
1628 int i;
1629
1630 for (i = 0; i < MAX_CONTEXT; i++) {
1631 ctrl_map = &afu->afu_map->ctrls[i].ctrl;
1632 /* disrupt any clients that could be running */
1633 /* e. g. clients that survived a master restart */
1634 writeq_be(0, &ctrl_map->rht_start);
1635 writeq_be(0, &ctrl_map->rht_cnt_id);
1636 writeq_be(0, &ctrl_map->ctx_cap);
1637 }
1638
1639 /* copy frequently used fields into afu */
1640 afu->ctx_hndl = (u16) cxl_process_element(cfg->mcctx);
1641 /* ctx_hndl is 16 bits in CAIA */
1642 afu->host_map = &afu->afu_map->hosts[afu->ctx_hndl].host;
1643 afu->ctrl_map = &afu->afu_map->ctrls[afu->ctx_hndl].ctrl;
1644
1645 /* Program the Endian Control for the master context */
1646 writeq_be(SISL_ENDIAN_CTRL, &afu->host_map->endian_ctrl);
1647
1648 /* initialize cmd fields that never change */
1649 for (i = 0; i < CXLFLASH_NUM_CMDS; i++) {
1650 afu->cmd[i].rcb.ctx_id = afu->ctx_hndl;
1651 afu->cmd[i].rcb.msi = SISL_MSI_RRQ_UPDATED;
1652 afu->cmd[i].rcb.rrq = 0x0;
1653 }
1654}
1655
1656/**
1657 * init_global() - initialize AFU global registers
1658 * @cxlflash: Internal structure associated with the host.
1659 */
1660int init_global(struct cxlflash_cfg *cfg)
1661{
1662 struct afu *afu = cfg->afu;
1663 u64 wwpn[NUM_FC_PORTS]; /* wwpn of AFU ports */
1664 int i = 0, num_ports = 0;
1665 int rc = 0;
1666 u64 reg;
1667
1668 rc = read_vpd(cfg, &wwpn[0]);
1669 if (rc) {
1670 pr_err("%s: could not read vpd rc=%d\n", __func__, rc);
1671 goto out;
1672 }
1673
1674 pr_debug("%s: wwpn0=0x%llX wwpn1=0x%llX\n", __func__, wwpn[0], wwpn[1]);
1675
1676 /* set up RRQ in AFU for master issued cmds */
1677 writeq_be((u64) afu->hrrq_start, &afu->host_map->rrq_start);
1678 writeq_be((u64) afu->hrrq_end, &afu->host_map->rrq_end);
1679
1680 /* AFU configuration */
1681 reg = readq_be(&afu->afu_map->global.regs.afu_config);
1682 reg |= SISL_AFUCONF_AR_ALL|SISL_AFUCONF_ENDIAN;
1683 /* enable all auto retry options and control endianness */
1684 /* leave others at default: */
1685 /* CTX_CAP write protected, mbox_r does not clear on read and */
1686 /* checker on if dual afu */
1687 writeq_be(reg, &afu->afu_map->global.regs.afu_config);
1688
1689 /* global port select: select either port */
1690 if (afu->internal_lun) {
1691 /* only use port 0 */
1692 writeq_be(PORT0, &afu->afu_map->global.regs.afu_port_sel);
1693 num_ports = NUM_FC_PORTS - 1;
1694 } else {
1695 writeq_be(BOTH_PORTS, &afu->afu_map->global.regs.afu_port_sel);
1696 num_ports = NUM_FC_PORTS;
1697 }
1698
1699 for (i = 0; i < num_ports; i++) {
1700 /* unmask all errors (but they are still masked at AFU) */
1701 writeq_be(0, &afu->afu_map->global.fc_regs[i][FC_ERRMSK / 8]);
1702 /* clear CRC error cnt & set a threshold */
1703 (void)readq_be(&afu->afu_map->global.
1704 fc_regs[i][FC_CNT_CRCERR / 8]);
1705 writeq_be(MC_CRC_THRESH, &afu->afu_map->global.fc_regs[i]
1706 [FC_CRC_THRESH / 8]);
1707
1708 /* set WWPNs. If already programmed, wwpn[i] is 0 */
1709 if (wwpn[i] != 0 &&
1710 afu_set_wwpn(afu, i,
1711 &afu->afu_map->global.fc_regs[i][0],
1712 wwpn[i])) {
1713 pr_err("%s: failed to set WWPN on port %d\n",
1714 __func__, i);
1715 rc = -EIO;
1716 goto out;
1717 }
1718 /* Programming WWPN back to back causes additional
1719 * offline/online transitions and a PLOGI
1720 */
1721 msleep(100);
1722
1723 }
1724
1725 /* set up master's own CTX_CAP to allow real mode, host translation */
1726 /* tbls, afu cmds and read/write GSCSI cmds. */
1727 /* First, unlock ctx_cap write by reading mbox */
1728 (void)readq_be(&afu->ctrl_map->mbox_r); /* unlock ctx_cap */
1729 writeq_be((SISL_CTX_CAP_REAL_MODE | SISL_CTX_CAP_HOST_XLATE |
1730 SISL_CTX_CAP_READ_CMD | SISL_CTX_CAP_WRITE_CMD |
1731 SISL_CTX_CAP_AFU_CMD | SISL_CTX_CAP_GSCSI_CMD),
1732 &afu->ctrl_map->ctx_cap);
1733 /* init heartbeat */
1734 afu->hb = readq_be(&afu->afu_map->global.regs.afu_hb);
1735
1736out:
1737 return rc;
1738}
1739
1740/**
1741 * start_afu() - initializes and starts the AFU
1742 * @cxlflash: Internal structure associated with the host.
1743 */
1744static int start_afu(struct cxlflash_cfg *cfg)
1745{
1746 struct afu *afu = cfg->afu;
1747 struct afu_cmd *cmd;
1748
1749 int i = 0;
1750 int rc = 0;
1751
1752 for (i = 0; i < CXLFLASH_NUM_CMDS; i++) {
1753 cmd = &afu->cmd[i];
1754
1755 init_completion(&cmd->cevent);
1756 spin_lock_init(&cmd->slock);
1757 cmd->parent = afu;
1758 }
1759
1760 init_pcr(cfg);
1761
1762 /* initialize RRQ pointers */
1763 afu->hrrq_start = &afu->rrq_entry[0];
1764 afu->hrrq_end = &afu->rrq_entry[NUM_RRQ_ENTRY - 1];
1765 afu->hrrq_curr = afu->hrrq_start;
1766 afu->toggle = 1;
1767
1768 rc = init_global(cfg);
1769
1770 pr_debug("%s: returning rc=%d\n", __func__, rc);
1771 return rc;
1772}
1773
1774/**
1775 * init_mc() - create and register as the master context
1776 * @cxlflash: Internal structure associated with the host.
1777 *
1778 * Return:
1779 * 0 on success
1780 * -ENOMEM when unable to obtain a context from CXL services
1781 * A failure value from CXL services.
1782 */
1783static int init_mc(struct cxlflash_cfg *cfg)
1784{
1785 struct cxl_context *ctx;
1786 struct device *dev = &cfg->dev->dev;
1787 struct afu *afu = cfg->afu;
1788 int rc = 0;
1789 enum undo_level level;
1790
1791 ctx = cxl_get_context(cfg->dev);
1792 if (unlikely(!ctx))
1793 return -ENOMEM;
1794 cfg->mcctx = ctx;
1795
1796 /* Set it up as a master with the CXL */
1797 cxl_set_master(ctx);
1798
1799 /* During initialization reset the AFU to start from a clean slate */
1800 rc = cxl_afu_reset(cfg->mcctx);
1801 if (unlikely(rc)) {
1802 dev_err(dev, "%s: initial AFU reset failed rc=%d\n",
1803 __func__, rc);
1804 level = RELEASE_CONTEXT;
1805 goto out;
1806 }
1807
1808 rc = cxl_allocate_afu_irqs(ctx, 3);
1809 if (unlikely(rc)) {
1810 dev_err(dev, "%s: call to allocate_afu_irqs failed rc=%d!\n",
1811 __func__, rc);
1812 level = RELEASE_CONTEXT;
1813 goto out;
1814 }
1815
1816 rc = cxl_map_afu_irq(ctx, 1, cxlflash_sync_err_irq, afu,
1817 "SISL_MSI_SYNC_ERROR");
1818 if (unlikely(rc <= 0)) {
1819 dev_err(dev, "%s: IRQ 1 (SISL_MSI_SYNC_ERROR) map failed!\n",
1820 __func__);
1821 level = FREE_IRQ;
1822 goto out;
1823 }
1824
1825 rc = cxl_map_afu_irq(ctx, 2, cxlflash_rrq_irq, afu,
1826 "SISL_MSI_RRQ_UPDATED");
1827 if (unlikely(rc <= 0)) {
1828 dev_err(dev, "%s: IRQ 2 (SISL_MSI_RRQ_UPDATED) map failed!\n",
1829 __func__);
1830 level = UNMAP_ONE;
1831 goto out;
1832 }
1833
1834 rc = cxl_map_afu_irq(ctx, 3, cxlflash_async_err_irq, afu,
1835 "SISL_MSI_ASYNC_ERROR");
1836 if (unlikely(rc <= 0)) {
1837 dev_err(dev, "%s: IRQ 3 (SISL_MSI_ASYNC_ERROR) map failed!\n",
1838 __func__);
1839 level = UNMAP_TWO;
1840 goto out;
1841 }
1842
1843 rc = 0;
1844
1845 /* This performs the equivalent of the CXL_IOCTL_START_WORK.
1846 * The CXL_IOCTL_GET_PROCESS_ELEMENT is implicit in the process
1847 * element (pe) that is embedded in the context (ctx)
1848 */
1849 rc = start_context(cfg);
1850 if (unlikely(rc)) {
1851 dev_err(dev, "%s: start context failed rc=%d\n", __func__, rc);
1852 level = UNMAP_THREE;
1853 goto out;
1854 }
1855ret:
1856 pr_debug("%s: returning rc=%d\n", __func__, rc);
1857 return rc;
1858out:
1859 term_mc(cfg, level);
1860 goto ret;
1861}
1862
1863/**
1864 * init_afu() - setup as master context and start AFU
1865 * @cxlflash: Internal structure associated with the host.
1866 *
1867 * This routine is a higher level of control for configuring the
1868 * AFU on probe and reset paths.
1869 *
1870 * Return:
1871 * 0 on success
1872 * -ENOMEM when unable to map the AFU MMIO space
1873 * A failure value from internal services.
1874 */
1875static int init_afu(struct cxlflash_cfg *cfg)
1876{
1877 u64 reg;
1878 int rc = 0;
1879 struct afu *afu = cfg->afu;
1880 struct device *dev = &cfg->dev->dev;
1881
1882 rc = init_mc(cfg);
1883 if (rc) {
1884 dev_err(dev, "%s: call to init_mc failed, rc=%d!\n",
1885 __func__, rc);
1886 goto err1;
1887 }
1888
1889 /* Map the entire MMIO space of the AFU.
1890 */
1891 afu->afu_map = cxl_psa_map(cfg->mcctx);
1892 if (!afu->afu_map) {
1893 rc = -ENOMEM;
1894 term_mc(cfg, UNDO_START);
1895 dev_err(dev, "%s: call to cxl_psa_map failed!\n", __func__);
1896 goto err1;
1897 }
1898
1899 /* don't byte reverse on reading afu_version, else the string form */
1900 /* will be backwards */
1901 reg = afu->afu_map->global.regs.afu_version;
1902 memcpy(afu->version, &reg, 8);
1903 afu->interface_version =
1904 readq_be(&afu->afu_map->global.regs.interface_version);
1905 pr_debug("%s: afu version %s, interface version 0x%llX\n",
1906 __func__, afu->version, afu->interface_version);
1907
1908 rc = start_afu(cfg);
1909 if (rc) {
1910 dev_err(dev, "%s: call to start_afu failed, rc=%d!\n",
1911 __func__, rc);
1912 term_mc(cfg, UNDO_START);
1913 cxl_psa_unmap((void *)afu->afu_map);
1914 afu->afu_map = NULL;
1915 goto err1;
1916 }
1917
1918 afu_err_intr_init(cfg->afu);
1919 atomic64_set(&afu->room, readq_be(&afu->host_map->cmd_room));
1920
1921err1:
1922 pr_debug("%s: returning rc=%d\n", __func__, rc);
1923 return rc;
1924}
1925
1926/**
1927 * cxlflash_send_cmd() - sends an AFU command
1928 * @afu: AFU associated with the host.
1929 * @cmd: AFU command to send.
1930 *
1931 * Return:
1932 * 0 on success
1933 * -1 on failure
1934 */
1935int cxlflash_send_cmd(struct afu *afu, struct afu_cmd *cmd)
1936{
1937 struct cxlflash_cfg *cfg = afu->parent;
1938 int nretry = 0;
1939 int rc = 0;
1940 u64 room;
1941 long newval;
1942
1943 /*
1944 * This routine is used by critical users such an AFU sync and to
1945 * send a task management function (TMF). Thus we want to retry a
1946 * bit before returning an error. To avoid the performance penalty
1947 * of MMIO, we spread the update of 'room' over multiple commands.
1948 */
1949retry:
1950 newval = atomic64_dec_if_positive(&afu->room);
1951 if (!newval) {
1952 do {
1953 room = readq_be(&afu->host_map->cmd_room);
1954 atomic64_set(&afu->room, room);
1955 if (room)
1956 goto write_ioarrin;
1957 udelay(nretry);
1958 } while (nretry++ < MC_ROOM_RETRY_CNT);
1959
1960 pr_err("%s: no cmd_room to send 0x%X\n",
1961 __func__, cmd->rcb.cdb[0]);
1962
1963 goto no_room;
1964 } else if (unlikely(newval < 0)) {
1965 /* This should be rare. i.e. Only if two threads race and
1966 * decrement before the MMIO read is done. In this case
1967 * just benefit from the other thread having updated
1968 * afu->room.
1969 */
1970 if (nretry++ < MC_ROOM_RETRY_CNT) {
1971 udelay(nretry);
1972 goto retry;
1973 }
1974
1975 goto no_room;
1976 }
1977
1978write_ioarrin:
1979 writeq_be((u64)&cmd->rcb, &afu->host_map->ioarrin);
1980out:
1981 pr_debug("%s: cmd=%p len=%d ea=%p rc=%d\n", __func__, cmd,
1982 cmd->rcb.data_len, (void *)cmd->rcb.data_ea, rc);
1983 return rc;
1984
1985no_room:
1986 afu->read_room = true;
1987 schedule_work(&cfg->work_q);
1988 rc = SCSI_MLQUEUE_HOST_BUSY;
1989 goto out;
1990}
1991
1992/**
1993 * cxlflash_wait_resp() - polls for a response or timeout to a sent AFU command
1994 * @afu: AFU associated with the host.
1995 * @cmd: AFU command that was sent.
1996 */
1997void cxlflash_wait_resp(struct afu *afu, struct afu_cmd *cmd)
1998{
1999 ulong timeout = jiffies + (cmd->rcb.timeout * 2 * HZ);
2000
2001 timeout = wait_for_completion_timeout(&cmd->cevent, timeout);
2002 if (!timeout)
2003 cxlflash_context_reset(cmd);
2004
2005 if (unlikely(cmd->sa.ioasc != 0))
2006 pr_err("%s: CMD 0x%X failed, IOASC: flags 0x%X, afu_rc 0x%X, "
2007 "scsi_rc 0x%X, fc_rc 0x%X\n", __func__, cmd->rcb.cdb[0],
2008 cmd->sa.rc.flags, cmd->sa.rc.afu_rc, cmd->sa.rc.scsi_rc,
2009 cmd->sa.rc.fc_rc);
2010}
2011
2012/**
2013 * cxlflash_afu_sync() - builds and sends an AFU sync command
2014 * @afu: AFU associated with the host.
2015 * @ctx_hndl_u: Identifies context requesting sync.
2016 * @res_hndl_u: Identifies resource requesting sync.
2017 * @mode: Type of sync to issue (lightweight, heavyweight, global).
2018 *
2019 * The AFU can only take 1 sync command at a time. This routine enforces this
2020 * limitation by using a mutex to provide exlusive access to the AFU during
2021 * the sync. This design point requires calling threads to not be on interrupt
2022 * context due to the possibility of sleeping during concurrent sync operations.
2023 *
2024 * Return:
2025 * 0 on success
2026 * -1 on failure
2027 */
2028int cxlflash_afu_sync(struct afu *afu, ctx_hndl_t ctx_hndl_u,
2029 res_hndl_t res_hndl_u, u8 mode)
2030{
2031 struct afu_cmd *cmd = NULL;
2032 int rc = 0;
2033 int retry_cnt = 0;
2034 static DEFINE_MUTEX(sync_active);
2035
2036 mutex_lock(&sync_active);
2037retry:
2038 cmd = cxlflash_cmd_checkout(afu);
2039 if (unlikely(!cmd)) {
2040 retry_cnt++;
2041 udelay(1000 * retry_cnt);
2042 if (retry_cnt < MC_RETRY_CNT)
2043 goto retry;
2044 pr_err("%s: could not get a free command\n", __func__);
2045 rc = -1;
2046 goto out;
2047 }
2048
2049 pr_debug("%s: afu=%p cmd=%p %d\n", __func__, afu, cmd, ctx_hndl_u);
2050
2051 memset(cmd->rcb.cdb, 0, sizeof(cmd->rcb.cdb));
2052
2053 cmd->rcb.req_flags = SISL_REQ_FLAGS_AFU_CMD;
2054 cmd->rcb.port_sel = 0x0; /* NA */
2055 cmd->rcb.lun_id = 0x0; /* NA */
2056 cmd->rcb.data_len = 0x0;
2057 cmd->rcb.data_ea = 0x0;
2058 cmd->rcb.timeout = MC_AFU_SYNC_TIMEOUT;
2059
2060 cmd->rcb.cdb[0] = 0xC0; /* AFU Sync */
2061 cmd->rcb.cdb[1] = mode;
2062
2063 /* The cdb is aligned, no unaligned accessors required */
2064 *((u16 *)&cmd->rcb.cdb[2]) = swab16(ctx_hndl_u);
2065 *((u32 *)&cmd->rcb.cdb[4]) = swab32(res_hndl_u);
2066
2067 rc = cxlflash_send_cmd(afu, cmd);
2068 if (unlikely(rc))
2069 goto out;
2070
2071 cxlflash_wait_resp(afu, cmd);
2072
2073 /* set on timeout */
2074 if (unlikely((cmd->sa.ioasc != 0) ||
2075 (cmd->sa.host_use_b[0] & B_ERROR)))
2076 rc = -1;
2077out:
2078 mutex_unlock(&sync_active);
2079 if (cmd)
2080 cxlflash_cmd_checkin(cmd);
2081 pr_debug("%s: returning rc=%d\n", __func__, rc);
2082 return rc;
2083}
2084
2085/**
2086 * cxlflash_afu_reset() - resets the AFU
2087 * @cxlflash: Internal structure associated with the host.
2088 *
2089 * Return:
2090 * 0 on success
2091 * A failure value from internal services.
2092 */
2093int cxlflash_afu_reset(struct cxlflash_cfg *cfg)
2094{
2095 int rc = 0;
2096 /* Stop the context before the reset. Since the context is
2097 * no longer available restart it after the reset is complete
2098 */
2099
2100 term_afu(cfg);
2101
2102 rc = init_afu(cfg);
2103
2104 pr_debug("%s: returning rc=%d\n", __func__, rc);
2105 return rc;
2106}
2107
2108/**
2109 * cxlflash_worker_thread() - work thread handler for the AFU
2110 * @work: Work structure contained within cxlflash associated with host.
2111 *
2112 * Handles the following events:
2113 * - Link reset which cannot be performed on interrupt context due to
2114 * blocking up to a few seconds
2115 * - Read AFU command room
2116 */
2117static void cxlflash_worker_thread(struct work_struct *work)
2118{
2119 struct cxlflash_cfg *cfg =
2120 container_of(work, struct cxlflash_cfg, work_q);
2121 struct afu *afu = cfg->afu;
2122 int port;
2123 ulong lock_flags;
2124
2125 spin_lock_irqsave(cfg->host->host_lock, lock_flags);
2126
2127 if (cfg->lr_state == LINK_RESET_REQUIRED) {
2128 port = cfg->lr_port;
2129 if (port < 0)
2130 pr_err("%s: invalid port index %d\n", __func__, port);
2131 else {
2132 spin_unlock_irqrestore(cfg->host->host_lock,
2133 lock_flags);
2134
2135 /* The reset can block... */
2136 afu_link_reset(afu, port,
2137 &afu->afu_map->
2138 global.fc_regs[port][0]);
2139 spin_lock_irqsave(cfg->host->host_lock, lock_flags);
2140 }
2141
2142 cfg->lr_state = LINK_RESET_COMPLETE;
2143 }
2144
2145 if (afu->read_room) {
2146 atomic64_set(&afu->room, readq_be(&afu->host_map->cmd_room));
2147 afu->read_room = false;
2148 }
2149
2150 spin_unlock_irqrestore(cfg->host->host_lock, lock_flags);
2151}
2152
2153/**
2154 * cxlflash_probe() - PCI entry point to add host
2155 * @pdev: PCI device associated with the host.
2156 * @dev_id: PCI device id associated with device.
2157 *
2158 * Return: 0 on success / non-zero on failure
2159 */
2160static int cxlflash_probe(struct pci_dev *pdev,
2161 const struct pci_device_id *dev_id)
2162{
2163 struct Scsi_Host *host;
2164 struct cxlflash_cfg *cfg = NULL;
2165 struct device *phys_dev;
2166 struct dev_dependent_vals *ddv;
2167 int rc = 0;
2168
2169 dev_dbg(&pdev->dev, "%s: Found CXLFLASH with IRQ: %d\n",
2170 __func__, pdev->irq);
2171
2172 ddv = (struct dev_dependent_vals *)dev_id->driver_data;
2173 driver_template.max_sectors = ddv->max_sectors;
2174
2175 host = scsi_host_alloc(&driver_template, sizeof(struct cxlflash_cfg));
2176 if (!host) {
2177 dev_err(&pdev->dev, "%s: call to scsi_host_alloc failed!\n",
2178 __func__);
2179 rc = -ENOMEM;
2180 goto out;
2181 }
2182
2183 host->max_id = CXLFLASH_MAX_NUM_TARGETS_PER_BUS;
2184 host->max_lun = CXLFLASH_MAX_NUM_LUNS_PER_TARGET;
2185 host->max_channel = NUM_FC_PORTS - 1;
2186 host->unique_id = host->host_no;
2187 host->max_cmd_len = CXLFLASH_MAX_CDB_LEN;
2188
2189 cfg = (struct cxlflash_cfg *)host->hostdata;
2190 cfg->host = host;
2191 rc = alloc_mem(cfg);
2192 if (rc) {
2193 dev_err(&pdev->dev, "%s: call to scsi_host_alloc failed!\n",
2194 __func__);
2195 rc = -ENOMEM;
2196 goto out;
2197 }
2198
2199 cfg->init_state = INIT_STATE_NONE;
2200 cfg->dev = pdev;
2201 cfg->dev_id = (struct pci_device_id *)dev_id;
2202 cfg->mcctx = NULL;
2203 cfg->err_recovery_active = 0;
2204
2205 init_waitqueue_head(&cfg->tmf_waitq);
2206 init_waitqueue_head(&cfg->eeh_waitq);
2207
2208 INIT_WORK(&cfg->work_q, cxlflash_worker_thread);
2209 cfg->lr_state = LINK_RESET_INVALID;
2210 cfg->lr_port = -1;
2211
2212 pci_set_drvdata(pdev, cfg);
2213
2214 /* Use the special service provided to look up the physical
2215 * PCI device, since we are called on the probe of the virtual
2216 * PCI host bus (vphb)
2217 */
2218 phys_dev = cxl_get_phys_dev(pdev);
2219 if (!dev_is_pci(phys_dev)) {
2220 pr_err("%s: not a pci dev\n", __func__);
2221 rc = -ENODEV;
2222 goto out_remove;
2223 }
2224 cfg->parent_dev = to_pci_dev(phys_dev);
2225
2226 cfg->cxl_afu = cxl_pci_to_afu(pdev);
2227
2228 rc = init_pci(cfg);
2229 if (rc) {
2230 dev_err(&pdev->dev, "%s: call to init_pci "
2231 "failed rc=%d!\n", __func__, rc);
2232 goto out_remove;
2233 }
2234 cfg->init_state = INIT_STATE_PCI;
2235
2236 rc = init_afu(cfg);
2237 if (rc) {
2238 dev_err(&pdev->dev, "%s: call to init_afu "
2239 "failed rc=%d!\n", __func__, rc);
2240 goto out_remove;
2241 }
2242 cfg->init_state = INIT_STATE_AFU;
2243
2244
2245 rc = init_scsi(cfg);
2246 if (rc) {
2247 dev_err(&pdev->dev, "%s: call to init_scsi "
2248 "failed rc=%d!\n", __func__, rc);
2249 goto out_remove;
2250 }
2251 cfg->init_state = INIT_STATE_SCSI;
2252
2253out:
2254 pr_debug("%s: returning rc=%d\n", __func__, rc);
2255 return rc;
2256
2257out_remove:
2258 cxlflash_remove(pdev);
2259 goto out;
2260}
2261
2262/*
2263 * PCI device structure
2264 */
2265static struct pci_driver cxlflash_driver = {
2266 .name = CXLFLASH_NAME,
2267 .id_table = cxlflash_pci_table,
2268 .probe = cxlflash_probe,
2269 .remove = cxlflash_remove,
2270};
2271
2272/**
2273 * init_cxlflash() - module entry point
2274 *
2275 * Return: 0 on success / non-zero on failure
2276 */
2277static int __init init_cxlflash(void)
2278{
2279 pr_info("%s: IBM Power CXL Flash Adapter: %s\n",
2280 __func__, CXLFLASH_DRIVER_DATE);
2281
2282 return pci_register_driver(&cxlflash_driver);
2283}
2284
2285/**
2286 * exit_cxlflash() - module exit point
2287 */
2288static void __exit exit_cxlflash(void)
2289{
2290 pci_unregister_driver(&cxlflash_driver);
2291}
2292
2293module_init(init_cxlflash);
2294module_exit(exit_cxlflash);
generated by cgit v1.2.2 (git 2.25.0) at 2025-03-21 11:00:26 -0400