1 // SPDX-License-Identifier: GPL-2.0
2
3 #define pr_fmt(fmt) "papr-scm: " fmt
4
5 #include <linux/of.h>
6 #include <linux/kernel.h>
7 #include <linux/module.h>
8 #include <linux/ioport.h>
9 #include <linux/slab.h>
10 #include <linux/ndctl.h>
11 #include <linux/sched.h>
12 #include <linux/libnvdimm.h>
13 #include <linux/platform_device.h>
14 #include <linux/delay.h>
15 #include <linux/seq_buf.h>
16 #include <linux/nd.h>
17
18 #include <asm/plpar_wrappers.h>
19 #include <asm/papr_pdsm.h>
20 #include <asm/mce.h>
21 #include <asm/unaligned.h>
22
23 #define BIND_ANY_ADDR (~0ul)
24
25 #define PAPR_SCM_DIMM_CMD_MASK \
26 ((1ul << ND_CMD_GET_CONFIG_SIZE) | \
27 (1ul << ND_CMD_GET_CONFIG_DATA) | \
28 (1ul << ND_CMD_SET_CONFIG_DATA) | \
29 (1ul << ND_CMD_CALL))
30
31 /* DIMM health bitmap bitmap indicators */
32 /* SCM device is unable to persist memory contents */
33 #define PAPR_PMEM_UNARMED (1ULL << (63 - 0))
34 /* SCM device failed to persist memory contents */
35 #define PAPR_PMEM_SHUTDOWN_DIRTY (1ULL << (63 - 1))
36 /* SCM device contents are persisted from previous IPL */
37 #define PAPR_PMEM_SHUTDOWN_CLEAN (1ULL << (63 - 2))
38 /* SCM device contents are not persisted from previous IPL */
39 #define PAPR_PMEM_EMPTY (1ULL << (63 - 3))
40 /* SCM device memory life remaining is critically low */
41 #define PAPR_PMEM_HEALTH_CRITICAL (1ULL << (63 - 4))
42 /* SCM device will be garded off next IPL due to failure */
43 #define PAPR_PMEM_HEALTH_FATAL (1ULL << (63 - 5))
44 /* SCM contents cannot persist due to current platform health status */
45 #define PAPR_PMEM_HEALTH_UNHEALTHY (1ULL << (63 - 6))
46 /* SCM device is unable to persist memory contents in certain conditions */
47 #define PAPR_PMEM_HEALTH_NON_CRITICAL (1ULL << (63 - 7))
48 /* SCM device is encrypted */
49 #define PAPR_PMEM_ENCRYPTED (1ULL << (63 - 8))
50 /* SCM device has been scrubbed and locked */
51 #define PAPR_PMEM_SCRUBBED_AND_LOCKED (1ULL << (63 - 9))
52
53 /* Bits status indicators for health bitmap indicating unarmed dimm */
54 #define PAPR_PMEM_UNARMED_MASK (PAPR_PMEM_UNARMED | \
55 PAPR_PMEM_HEALTH_UNHEALTHY)
56
57 /* Bits status indicators for health bitmap indicating unflushed dimm */
58 #define PAPR_PMEM_BAD_SHUTDOWN_MASK (PAPR_PMEM_SHUTDOWN_DIRTY)
59
60 /* Bits status indicators for health bitmap indicating unrestored dimm */
61 #define PAPR_PMEM_BAD_RESTORE_MASK (PAPR_PMEM_EMPTY)
62
63 /* Bit status indicators for smart event notification */
64 #define PAPR_PMEM_SMART_EVENT_MASK (PAPR_PMEM_HEALTH_CRITICAL | \
65 PAPR_PMEM_HEALTH_FATAL | \
66 PAPR_PMEM_HEALTH_UNHEALTHY)
67
68 #define PAPR_SCM_PERF_STATS_EYECATCHER __stringify(SCMSTATS)
69 #define PAPR_SCM_PERF_STATS_VERSION 0x1
70
71 /* Struct holding a single performance metric */
72 struct papr_scm_perf_stat {
73 u8 stat_id[8];
74 __be64 stat_val;
75 } __packed;
76
77 /* Struct exchanged between kernel and PHYP for fetching drc perf stats */
78 struct papr_scm_perf_stats {
79 u8 eye_catcher[8];
80 /* Should be PAPR_SCM_PERF_STATS_VERSION */
81 __be32 stats_version;
82 /* Number of stats following */
83 __be32 num_statistics;
84 /* zero or more performance matrics */
85 struct papr_scm_perf_stat scm_statistic[];
86 } __packed;
87
88 /* private struct associated with each region */
89 struct papr_scm_priv {
90 struct platform_device *pdev;
91 struct device_node *dn;
92 uint32_t drc_index;
93 uint64_t blocks;
94 uint64_t block_size;
95 int metadata_size;
96 bool is_volatile;
97
98 uint64_t bound_addr;
99
100 struct nvdimm_bus_descriptor bus_desc;
101 struct nvdimm_bus *bus;
102 struct nvdimm *nvdimm;
103 struct resource res;
104 struct nd_region *region;
105 struct nd_interleave_set nd_set;
106 struct list_head region_list;
107
108 /* Protect dimm health data from concurrent read/writes */
109 struct mutex health_mutex;
110
111 /* Last time the health information of the dimm was updated */
112 unsigned long lasthealth_jiffies;
113
114 /* Health information for the dimm */
115 u64 health_bitmap;
116
117 /* length of the stat buffer as expected by phyp */
118 size_t stat_buffer_len;
119 };
120
121 static LIST_HEAD(papr_nd_regions);
122 static DEFINE_MUTEX(papr_ndr_lock);
123
drc_pmem_bind(struct papr_scm_priv * p)124 static int drc_pmem_bind(struct papr_scm_priv *p)
125 {
126 unsigned long ret[PLPAR_HCALL_BUFSIZE];
127 uint64_t saved = 0;
128 uint64_t token;
129 int64_t rc;
130
131 /*
132 * When the hypervisor cannot map all the requested memory in a single
133 * hcall it returns H_BUSY and we call again with the token until
134 * we get H_SUCCESS. Aborting the retry loop before getting H_SUCCESS
135 * leave the system in an undefined state, so we wait.
136 */
137 token = 0;
138
139 do {
140 rc = plpar_hcall(H_SCM_BIND_MEM, ret, p->drc_index, 0,
141 p->blocks, BIND_ANY_ADDR, token);
142 token = ret[0];
143 if (!saved)
144 saved = ret[1];
145 cond_resched();
146 } while (rc == H_BUSY);
147
148 if (rc)
149 return rc;
150
151 p->bound_addr = saved;
152 dev_dbg(&p->pdev->dev, "bound drc 0x%x to 0x%lx\n",
153 p->drc_index, (unsigned long)saved);
154 return rc;
155 }
156
drc_pmem_unbind(struct papr_scm_priv * p)157 static void drc_pmem_unbind(struct papr_scm_priv *p)
158 {
159 unsigned long ret[PLPAR_HCALL_BUFSIZE];
160 uint64_t token = 0;
161 int64_t rc;
162
163 dev_dbg(&p->pdev->dev, "unbind drc 0x%x\n", p->drc_index);
164
165 /* NB: unbind has the same retry requirements as drc_pmem_bind() */
166 do {
167
168 /* Unbind of all SCM resources associated with drcIndex */
169 rc = plpar_hcall(H_SCM_UNBIND_ALL, ret, H_UNBIND_SCOPE_DRC,
170 p->drc_index, token);
171 token = ret[0];
172
173 /* Check if we are stalled for some time */
174 if (H_IS_LONG_BUSY(rc)) {
175 msleep(get_longbusy_msecs(rc));
176 rc = H_BUSY;
177 } else if (rc == H_BUSY) {
178 cond_resched();
179 }
180
181 } while (rc == H_BUSY);
182
183 if (rc)
184 dev_err(&p->pdev->dev, "unbind error: %lld\n", rc);
185 else
186 dev_dbg(&p->pdev->dev, "unbind drc 0x%x complete\n",
187 p->drc_index);
188
189 return;
190 }
191
drc_pmem_query_n_bind(struct papr_scm_priv * p)192 static int drc_pmem_query_n_bind(struct papr_scm_priv *p)
193 {
194 unsigned long start_addr;
195 unsigned long end_addr;
196 unsigned long ret[PLPAR_HCALL_BUFSIZE];
197 int64_t rc;
198
199
200 rc = plpar_hcall(H_SCM_QUERY_BLOCK_MEM_BINDING, ret,
201 p->drc_index, 0);
202 if (rc)
203 goto err_out;
204 start_addr = ret[0];
205
206 /* Make sure the full region is bound. */
207 rc = plpar_hcall(H_SCM_QUERY_BLOCK_MEM_BINDING, ret,
208 p->drc_index, p->blocks - 1);
209 if (rc)
210 goto err_out;
211 end_addr = ret[0];
212
213 if ((end_addr - start_addr) != ((p->blocks - 1) * p->block_size))
214 goto err_out;
215
216 p->bound_addr = start_addr;
217 dev_dbg(&p->pdev->dev, "bound drc 0x%x to 0x%lx\n", p->drc_index, start_addr);
218 return rc;
219
220 err_out:
221 dev_info(&p->pdev->dev,
222 "Failed to query, trying an unbind followed by bind");
223 drc_pmem_unbind(p);
224 return drc_pmem_bind(p);
225 }
226
227 /*
228 * Query the Dimm performance stats from PHYP and copy them (if returned) to
229 * provided struct papr_scm_perf_stats instance 'stats' that can hold atleast
230 * (num_stats + header) bytes.
231 * - If buff_stats == NULL the return value is the size in byes of the buffer
232 * needed to hold all supported performance-statistics.
233 * - If buff_stats != NULL and num_stats == 0 then we copy all known
234 * performance-statistics to 'buff_stat' and expect to be large enough to
235 * hold them.
236 * - if buff_stats != NULL and num_stats > 0 then copy the requested
237 * performance-statistics to buff_stats.
238 */
drc_pmem_query_stats(struct papr_scm_priv * p,struct papr_scm_perf_stats * buff_stats,unsigned int num_stats)239 static ssize_t drc_pmem_query_stats(struct papr_scm_priv *p,
240 struct papr_scm_perf_stats *buff_stats,
241 unsigned int num_stats)
242 {
243 unsigned long ret[PLPAR_HCALL_BUFSIZE];
244 size_t size;
245 s64 rc;
246
247 /* Setup the out buffer */
248 if (buff_stats) {
249 memcpy(buff_stats->eye_catcher,
250 PAPR_SCM_PERF_STATS_EYECATCHER, 8);
251 buff_stats->stats_version =
252 cpu_to_be32(PAPR_SCM_PERF_STATS_VERSION);
253 buff_stats->num_statistics =
254 cpu_to_be32(num_stats);
255
256 /*
257 * Calculate the buffer size based on num-stats provided
258 * or use the prefetched max buffer length
259 */
260 if (num_stats)
261 /* Calculate size from the num_stats */
262 size = sizeof(struct papr_scm_perf_stats) +
263 num_stats * sizeof(struct papr_scm_perf_stat);
264 else
265 size = p->stat_buffer_len;
266 } else {
267 /* In case of no out buffer ignore the size */
268 size = 0;
269 }
270
271 /* Do the HCALL asking PHYP for info */
272 rc = plpar_hcall(H_SCM_PERFORMANCE_STATS, ret, p->drc_index,
273 buff_stats ? virt_to_phys(buff_stats) : 0,
274 size);
275
276 /* Check if the error was due to an unknown stat-id */
277 if (rc == H_PARTIAL) {
278 dev_err(&p->pdev->dev,
279 "Unknown performance stats, Err:0x%016lX\n", ret[0]);
280 return -ENOENT;
281 } else if (rc != H_SUCCESS) {
282 dev_err(&p->pdev->dev,
283 "Failed to query performance stats, Err:%lld\n", rc);
284 return -EIO;
285
286 } else if (!size) {
287 /* Handle case where stat buffer size was requested */
288 dev_dbg(&p->pdev->dev,
289 "Performance stats size %ld\n", ret[0]);
290 return ret[0];
291 }
292
293 /* Successfully fetched the requested stats from phyp */
294 dev_dbg(&p->pdev->dev,
295 "Performance stats returned %d stats\n",
296 be32_to_cpu(buff_stats->num_statistics));
297 return 0;
298 }
299
300 /*
301 * Issue hcall to retrieve dimm health info and populate papr_scm_priv with the
302 * health information.
303 */
__drc_pmem_query_health(struct papr_scm_priv * p)304 static int __drc_pmem_query_health(struct papr_scm_priv *p)
305 {
306 unsigned long ret[PLPAR_HCALL_BUFSIZE];
307 long rc;
308
309 /* issue the hcall */
310 rc = plpar_hcall(H_SCM_HEALTH, ret, p->drc_index);
311 if (rc != H_SUCCESS) {
312 dev_err(&p->pdev->dev,
313 "Failed to query health information, Err:%ld\n", rc);
314 return -ENXIO;
315 }
316
317 p->lasthealth_jiffies = jiffies;
318 p->health_bitmap = ret[0] & ret[1];
319
320 dev_dbg(&p->pdev->dev,
321 "Queried dimm health info. Bitmap:0x%016lx Mask:0x%016lx\n",
322 ret[0], ret[1]);
323
324 return 0;
325 }
326
327 /* Min interval in seconds for assuming stable dimm health */
328 #define MIN_HEALTH_QUERY_INTERVAL 60
329
330 /* Query cached health info and if needed call drc_pmem_query_health */
drc_pmem_query_health(struct papr_scm_priv * p)331 static int drc_pmem_query_health(struct papr_scm_priv *p)
332 {
333 unsigned long cache_timeout;
334 int rc;
335
336 /* Protect concurrent modifications to papr_scm_priv */
337 rc = mutex_lock_interruptible(&p->health_mutex);
338 if (rc)
339 return rc;
340
341 /* Jiffies offset for which the health data is assumed to be same */
342 cache_timeout = p->lasthealth_jiffies +
343 msecs_to_jiffies(MIN_HEALTH_QUERY_INTERVAL * 1000);
344
345 /* Fetch new health info is its older than MIN_HEALTH_QUERY_INTERVAL */
346 if (time_after(jiffies, cache_timeout))
347 rc = __drc_pmem_query_health(p);
348 else
349 /* Assume cached health data is valid */
350 rc = 0;
351
352 mutex_unlock(&p->health_mutex);
353 return rc;
354 }
355
papr_scm_meta_get(struct papr_scm_priv * p,struct nd_cmd_get_config_data_hdr * hdr)356 static int papr_scm_meta_get(struct papr_scm_priv *p,
357 struct nd_cmd_get_config_data_hdr *hdr)
358 {
359 unsigned long data[PLPAR_HCALL_BUFSIZE];
360 unsigned long offset, data_offset;
361 int len, read;
362 int64_t ret;
363
364 if ((hdr->in_offset + hdr->in_length) > p->metadata_size)
365 return -EINVAL;
366
367 for (len = hdr->in_length; len; len -= read) {
368
369 data_offset = hdr->in_length - len;
370 offset = hdr->in_offset + data_offset;
371
372 if (len >= 8)
373 read = 8;
374 else if (len >= 4)
375 read = 4;
376 else if (len >= 2)
377 read = 2;
378 else
379 read = 1;
380
381 ret = plpar_hcall(H_SCM_READ_METADATA, data, p->drc_index,
382 offset, read);
383
384 if (ret == H_PARAMETER) /* bad DRC index */
385 return -ENODEV;
386 if (ret)
387 return -EINVAL; /* other invalid parameter */
388
389 switch (read) {
390 case 8:
391 *(uint64_t *)(hdr->out_buf + data_offset) = be64_to_cpu(data[0]);
392 break;
393 case 4:
394 *(uint32_t *)(hdr->out_buf + data_offset) = be32_to_cpu(data[0] & 0xffffffff);
395 break;
396
397 case 2:
398 *(uint16_t *)(hdr->out_buf + data_offset) = be16_to_cpu(data[0] & 0xffff);
399 break;
400
401 case 1:
402 *(uint8_t *)(hdr->out_buf + data_offset) = (data[0] & 0xff);
403 break;
404 }
405 }
406 return 0;
407 }
408
papr_scm_meta_set(struct papr_scm_priv * p,struct nd_cmd_set_config_hdr * hdr)409 static int papr_scm_meta_set(struct papr_scm_priv *p,
410 struct nd_cmd_set_config_hdr *hdr)
411 {
412 unsigned long offset, data_offset;
413 int len, wrote;
414 unsigned long data;
415 __be64 data_be;
416 int64_t ret;
417
418 if ((hdr->in_offset + hdr->in_length) > p->metadata_size)
419 return -EINVAL;
420
421 for (len = hdr->in_length; len; len -= wrote) {
422
423 data_offset = hdr->in_length - len;
424 offset = hdr->in_offset + data_offset;
425
426 if (len >= 8) {
427 data = *(uint64_t *)(hdr->in_buf + data_offset);
428 data_be = cpu_to_be64(data);
429 wrote = 8;
430 } else if (len >= 4) {
431 data = *(uint32_t *)(hdr->in_buf + data_offset);
432 data &= 0xffffffff;
433 data_be = cpu_to_be32(data);
434 wrote = 4;
435 } else if (len >= 2) {
436 data = *(uint16_t *)(hdr->in_buf + data_offset);
437 data &= 0xffff;
438 data_be = cpu_to_be16(data);
439 wrote = 2;
440 } else {
441 data_be = *(uint8_t *)(hdr->in_buf + data_offset);
442 data_be &= 0xff;
443 wrote = 1;
444 }
445
446 ret = plpar_hcall_norets(H_SCM_WRITE_METADATA, p->drc_index,
447 offset, data_be, wrote);
448 if (ret == H_PARAMETER) /* bad DRC index */
449 return -ENODEV;
450 if (ret)
451 return -EINVAL; /* other invalid parameter */
452 }
453
454 return 0;
455 }
456
457 /*
458 * Do a sanity checks on the inputs args to dimm-control function and return
459 * '0' if valid. Validation of PDSM payloads happens later in
460 * papr_scm_service_pdsm.
461 */
is_cmd_valid(struct nvdimm * nvdimm,unsigned int cmd,void * buf,unsigned int buf_len)462 static int is_cmd_valid(struct nvdimm *nvdimm, unsigned int cmd, void *buf,
463 unsigned int buf_len)
464 {
465 unsigned long cmd_mask = PAPR_SCM_DIMM_CMD_MASK;
466 struct nd_cmd_pkg *nd_cmd;
467 struct papr_scm_priv *p;
468 enum papr_pdsm pdsm;
469
470 /* Only dimm-specific calls are supported atm */
471 if (!nvdimm)
472 return -EINVAL;
473
474 /* get the provider data from struct nvdimm */
475 p = nvdimm_provider_data(nvdimm);
476
477 if (!test_bit(cmd, &cmd_mask)) {
478 dev_dbg(&p->pdev->dev, "Unsupported cmd=%u\n", cmd);
479 return -EINVAL;
480 }
481
482 /* For CMD_CALL verify pdsm request */
483 if (cmd == ND_CMD_CALL) {
484 /* Verify the envelope and envelop size */
485 if (!buf ||
486 buf_len < (sizeof(struct nd_cmd_pkg) + ND_PDSM_HDR_SIZE)) {
487 dev_dbg(&p->pdev->dev, "Invalid pkg size=%u\n",
488 buf_len);
489 return -EINVAL;
490 }
491
492 /* Verify that the nd_cmd_pkg.nd_family is correct */
493 nd_cmd = (struct nd_cmd_pkg *)buf;
494
495 if (nd_cmd->nd_family != NVDIMM_FAMILY_PAPR) {
496 dev_dbg(&p->pdev->dev, "Invalid pkg family=0x%llx\n",
497 nd_cmd->nd_family);
498 return -EINVAL;
499 }
500
501 pdsm = (enum papr_pdsm)nd_cmd->nd_command;
502
503 /* Verify if the pdsm command is valid */
504 if (pdsm <= PAPR_PDSM_MIN || pdsm >= PAPR_PDSM_MAX) {
505 dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Invalid PDSM\n",
506 pdsm);
507 return -EINVAL;
508 }
509
510 /* Have enough space to hold returned 'nd_pkg_pdsm' header */
511 if (nd_cmd->nd_size_out < ND_PDSM_HDR_SIZE) {
512 dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Invalid payload\n",
513 pdsm);
514 return -EINVAL;
515 }
516 }
517
518 /* Let the command be further processed */
519 return 0;
520 }
521
papr_pdsm_fuel_gauge(struct papr_scm_priv * p,union nd_pdsm_payload * payload)522 static int papr_pdsm_fuel_gauge(struct papr_scm_priv *p,
523 union nd_pdsm_payload *payload)
524 {
525 int rc, size;
526 u64 statval;
527 struct papr_scm_perf_stat *stat;
528 struct papr_scm_perf_stats *stats;
529
530 /* Silently fail if fetching performance metrics isn't supported */
531 if (!p->stat_buffer_len)
532 return 0;
533
534 /* Allocate request buffer enough to hold single performance stat */
535 size = sizeof(struct papr_scm_perf_stats) +
536 sizeof(struct papr_scm_perf_stat);
537
538 stats = kzalloc(size, GFP_KERNEL);
539 if (!stats)
540 return -ENOMEM;
541
542 stat = &stats->scm_statistic[0];
543 memcpy(&stat->stat_id, "MemLife ", sizeof(stat->stat_id));
544 stat->stat_val = 0;
545
546 /* Fetch the fuel gauge and populate it in payload */
547 rc = drc_pmem_query_stats(p, stats, 1);
548 if (rc < 0) {
549 dev_dbg(&p->pdev->dev, "Err(%d) fetching fuel gauge\n", rc);
550 goto free_stats;
551 }
552
553 statval = be64_to_cpu(stat->stat_val);
554 dev_dbg(&p->pdev->dev,
555 "Fetched fuel-gauge %llu", statval);
556 payload->health.extension_flags |=
557 PDSM_DIMM_HEALTH_RUN_GAUGE_VALID;
558 payload->health.dimm_fuel_gauge = statval;
559
560 rc = sizeof(struct nd_papr_pdsm_health);
561
562 free_stats:
563 kfree(stats);
564 return rc;
565 }
566
567 /* Fetch the DIMM health info and populate it in provided package. */
papr_pdsm_health(struct papr_scm_priv * p,union nd_pdsm_payload * payload)568 static int papr_pdsm_health(struct papr_scm_priv *p,
569 union nd_pdsm_payload *payload)
570 {
571 int rc;
572
573 /* Ensure dimm health mutex is taken preventing concurrent access */
574 rc = mutex_lock_interruptible(&p->health_mutex);
575 if (rc)
576 goto out;
577
578 /* Always fetch upto date dimm health data ignoring cached values */
579 rc = __drc_pmem_query_health(p);
580 if (rc) {
581 mutex_unlock(&p->health_mutex);
582 goto out;
583 }
584
585 /* update health struct with various flags derived from health bitmap */
586 payload->health = (struct nd_papr_pdsm_health) {
587 .extension_flags = 0,
588 .dimm_unarmed = !!(p->health_bitmap & PAPR_PMEM_UNARMED_MASK),
589 .dimm_bad_shutdown = !!(p->health_bitmap & PAPR_PMEM_BAD_SHUTDOWN_MASK),
590 .dimm_bad_restore = !!(p->health_bitmap & PAPR_PMEM_BAD_RESTORE_MASK),
591 .dimm_scrubbed = !!(p->health_bitmap & PAPR_PMEM_SCRUBBED_AND_LOCKED),
592 .dimm_locked = !!(p->health_bitmap & PAPR_PMEM_SCRUBBED_AND_LOCKED),
593 .dimm_encrypted = !!(p->health_bitmap & PAPR_PMEM_ENCRYPTED),
594 .dimm_health = PAPR_PDSM_DIMM_HEALTHY,
595 };
596
597 /* Update field dimm_health based on health_bitmap flags */
598 if (p->health_bitmap & PAPR_PMEM_HEALTH_FATAL)
599 payload->health.dimm_health = PAPR_PDSM_DIMM_FATAL;
600 else if (p->health_bitmap & PAPR_PMEM_HEALTH_CRITICAL)
601 payload->health.dimm_health = PAPR_PDSM_DIMM_CRITICAL;
602 else if (p->health_bitmap & PAPR_PMEM_HEALTH_UNHEALTHY)
603 payload->health.dimm_health = PAPR_PDSM_DIMM_UNHEALTHY;
604
605 /* struct populated hence can release the mutex now */
606 mutex_unlock(&p->health_mutex);
607
608 /* Populate the fuel gauge meter in the payload */
609 papr_pdsm_fuel_gauge(p, payload);
610
611 rc = sizeof(struct nd_papr_pdsm_health);
612
613 out:
614 return rc;
615 }
616
617 /*
618 * 'struct pdsm_cmd_desc'
619 * Identifies supported PDSMs' expected length of in/out payloads
620 * and pdsm service function.
621 *
622 * size_in : Size of input payload if any in the PDSM request.
623 * size_out : Size of output payload if any in the PDSM request.
624 * service : Service function for the PDSM request. Return semantics:
625 * rc < 0 : Error servicing PDSM and rc indicates the error.
626 * rc >=0 : Serviced successfully and 'rc' indicate number of
627 * bytes written to payload.
628 */
629 struct pdsm_cmd_desc {
630 u32 size_in;
631 u32 size_out;
632 int (*service)(struct papr_scm_priv *dimm,
633 union nd_pdsm_payload *payload);
634 };
635
636 /* Holds all supported PDSMs' command descriptors */
637 static const struct pdsm_cmd_desc __pdsm_cmd_descriptors[] = {
638 [PAPR_PDSM_MIN] = {
639 .size_in = 0,
640 .size_out = 0,
641 .service = NULL,
642 },
643 /* New PDSM command descriptors to be added below */
644
645 [PAPR_PDSM_HEALTH] = {
646 .size_in = 0,
647 .size_out = sizeof(struct nd_papr_pdsm_health),
648 .service = papr_pdsm_health,
649 },
650 /* Empty */
651 [PAPR_PDSM_MAX] = {
652 .size_in = 0,
653 .size_out = 0,
654 .service = NULL,
655 },
656 };
657
658 /* Given a valid pdsm cmd return its command descriptor else return NULL */
pdsm_cmd_desc(enum papr_pdsm cmd)659 static inline const struct pdsm_cmd_desc *pdsm_cmd_desc(enum papr_pdsm cmd)
660 {
661 if (cmd >= 0 || cmd < ARRAY_SIZE(__pdsm_cmd_descriptors))
662 return &__pdsm_cmd_descriptors[cmd];
663
664 return NULL;
665 }
666
667 /*
668 * For a given pdsm request call an appropriate service function.
669 * Returns errors if any while handling the pdsm command package.
670 */
papr_scm_service_pdsm(struct papr_scm_priv * p,struct nd_cmd_pkg * pkg)671 static int papr_scm_service_pdsm(struct papr_scm_priv *p,
672 struct nd_cmd_pkg *pkg)
673 {
674 /* Get the PDSM header and PDSM command */
675 struct nd_pkg_pdsm *pdsm_pkg = (struct nd_pkg_pdsm *)pkg->nd_payload;
676 enum papr_pdsm pdsm = (enum papr_pdsm)pkg->nd_command;
677 const struct pdsm_cmd_desc *pdsc;
678 int rc;
679
680 /* Fetch corresponding pdsm descriptor for validation and servicing */
681 pdsc = pdsm_cmd_desc(pdsm);
682
683 /* Validate pdsm descriptor */
684 /* Ensure that reserved fields are 0 */
685 if (pdsm_pkg->reserved[0] || pdsm_pkg->reserved[1]) {
686 dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Invalid reserved field\n",
687 pdsm);
688 return -EINVAL;
689 }
690
691 /* If pdsm expects some input, then ensure that the size_in matches */
692 if (pdsc->size_in &&
693 pkg->nd_size_in != (pdsc->size_in + ND_PDSM_HDR_SIZE)) {
694 dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Mismatched size_in=%d\n",
695 pdsm, pkg->nd_size_in);
696 return -EINVAL;
697 }
698
699 /* If pdsm wants to return data, then ensure that size_out matches */
700 if (pdsc->size_out &&
701 pkg->nd_size_out != (pdsc->size_out + ND_PDSM_HDR_SIZE)) {
702 dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Mismatched size_out=%d\n",
703 pdsm, pkg->nd_size_out);
704 return -EINVAL;
705 }
706
707 /* Service the pdsm */
708 if (pdsc->service) {
709 dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Servicing..\n", pdsm);
710
711 rc = pdsc->service(p, &pdsm_pkg->payload);
712
713 if (rc < 0) {
714 /* error encountered while servicing pdsm */
715 pdsm_pkg->cmd_status = rc;
716 pkg->nd_fw_size = ND_PDSM_HDR_SIZE;
717 } else {
718 /* pdsm serviced and 'rc' bytes written to payload */
719 pdsm_pkg->cmd_status = 0;
720 pkg->nd_fw_size = ND_PDSM_HDR_SIZE + rc;
721 }
722 } else {
723 dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Unsupported PDSM request\n",
724 pdsm);
725 pdsm_pkg->cmd_status = -ENOENT;
726 pkg->nd_fw_size = ND_PDSM_HDR_SIZE;
727 }
728
729 return pdsm_pkg->cmd_status;
730 }
731
papr_scm_ndctl(struct nvdimm_bus_descriptor * nd_desc,struct nvdimm * nvdimm,unsigned int cmd,void * buf,unsigned int buf_len,int * cmd_rc)732 static int papr_scm_ndctl(struct nvdimm_bus_descriptor *nd_desc,
733 struct nvdimm *nvdimm, unsigned int cmd, void *buf,
734 unsigned int buf_len, int *cmd_rc)
735 {
736 struct nd_cmd_get_config_size *get_size_hdr;
737 struct nd_cmd_pkg *call_pkg = NULL;
738 struct papr_scm_priv *p;
739 int rc;
740
741 rc = is_cmd_valid(nvdimm, cmd, buf, buf_len);
742 if (rc) {
743 pr_debug("Invalid cmd=0x%x. Err=%d\n", cmd, rc);
744 return rc;
745 }
746
747 /* Use a local variable in case cmd_rc pointer is NULL */
748 if (!cmd_rc)
749 cmd_rc = &rc;
750
751 p = nvdimm_provider_data(nvdimm);
752
753 switch (cmd) {
754 case ND_CMD_GET_CONFIG_SIZE:
755 get_size_hdr = buf;
756
757 get_size_hdr->status = 0;
758 get_size_hdr->max_xfer = 8;
759 get_size_hdr->config_size = p->metadata_size;
760 *cmd_rc = 0;
761 break;
762
763 case ND_CMD_GET_CONFIG_DATA:
764 *cmd_rc = papr_scm_meta_get(p, buf);
765 break;
766
767 case ND_CMD_SET_CONFIG_DATA:
768 *cmd_rc = papr_scm_meta_set(p, buf);
769 break;
770
771 case ND_CMD_CALL:
772 call_pkg = (struct nd_cmd_pkg *)buf;
773 *cmd_rc = papr_scm_service_pdsm(p, call_pkg);
774 break;
775
776 default:
777 dev_dbg(&p->pdev->dev, "Unknown command = %d\n", cmd);
778 return -EINVAL;
779 }
780
781 dev_dbg(&p->pdev->dev, "returned with cmd_rc = %d\n", *cmd_rc);
782
783 return 0;
784 }
785
perf_stats_show(struct device * dev,struct device_attribute * attr,char * buf)786 static ssize_t perf_stats_show(struct device *dev,
787 struct device_attribute *attr, char *buf)
788 {
789 int index;
790 ssize_t rc;
791 struct seq_buf s;
792 struct papr_scm_perf_stat *stat;
793 struct papr_scm_perf_stats *stats;
794 struct nvdimm *dimm = to_nvdimm(dev);
795 struct papr_scm_priv *p = nvdimm_provider_data(dimm);
796
797 if (!p->stat_buffer_len)
798 return -ENOENT;
799
800 /* Allocate the buffer for phyp where stats are written */
801 stats = kzalloc(p->stat_buffer_len, GFP_KERNEL);
802 if (!stats)
803 return -ENOMEM;
804
805 /* Ask phyp to return all dimm perf stats */
806 rc = drc_pmem_query_stats(p, stats, 0);
807 if (rc)
808 goto free_stats;
809 /*
810 * Go through the returned output buffer and print stats and
811 * values. Since stat_id is essentially a char string of
812 * 8 bytes, simply use the string format specifier to print it.
813 */
814 seq_buf_init(&s, buf, PAGE_SIZE);
815 for (index = 0, stat = stats->scm_statistic;
816 index < be32_to_cpu(stats->num_statistics);
817 ++index, ++stat) {
818 seq_buf_printf(&s, "%.8s = 0x%016llX\n",
819 stat->stat_id,
820 be64_to_cpu(stat->stat_val));
821 }
822
823 free_stats:
824 kfree(stats);
825 return rc ? rc : (ssize_t)seq_buf_used(&s);
826 }
827 static DEVICE_ATTR_ADMIN_RO(perf_stats);
828
flags_show(struct device * dev,struct device_attribute * attr,char * buf)829 static ssize_t flags_show(struct device *dev,
830 struct device_attribute *attr, char *buf)
831 {
832 struct nvdimm *dimm = to_nvdimm(dev);
833 struct papr_scm_priv *p = nvdimm_provider_data(dimm);
834 struct seq_buf s;
835 u64 health;
836 int rc;
837
838 rc = drc_pmem_query_health(p);
839 if (rc)
840 return rc;
841
842 /* Copy health_bitmap locally, check masks & update out buffer */
843 health = READ_ONCE(p->health_bitmap);
844
845 seq_buf_init(&s, buf, PAGE_SIZE);
846 if (health & PAPR_PMEM_UNARMED_MASK)
847 seq_buf_printf(&s, "not_armed ");
848
849 if (health & PAPR_PMEM_BAD_SHUTDOWN_MASK)
850 seq_buf_printf(&s, "flush_fail ");
851
852 if (health & PAPR_PMEM_BAD_RESTORE_MASK)
853 seq_buf_printf(&s, "restore_fail ");
854
855 if (health & PAPR_PMEM_ENCRYPTED)
856 seq_buf_printf(&s, "encrypted ");
857
858 if (health & PAPR_PMEM_SMART_EVENT_MASK)
859 seq_buf_printf(&s, "smart_notify ");
860
861 if (health & PAPR_PMEM_SCRUBBED_AND_LOCKED)
862 seq_buf_printf(&s, "scrubbed locked ");
863
864 if (seq_buf_used(&s))
865 seq_buf_printf(&s, "\n");
866
867 return seq_buf_used(&s);
868 }
869 DEVICE_ATTR_RO(flags);
870
papr_nd_attribute_visible(struct kobject * kobj,struct attribute * attr,int n)871 static umode_t papr_nd_attribute_visible(struct kobject *kobj,
872 struct attribute *attr, int n)
873 {
874 struct device *dev = kobj_to_dev(kobj);
875 struct nvdimm *nvdimm = to_nvdimm(dev);
876 struct papr_scm_priv *p = nvdimm_provider_data(nvdimm);
877
878 /* For if perf-stats not available remove perf_stats sysfs */
879 if (attr == &dev_attr_perf_stats.attr && p->stat_buffer_len == 0)
880 return 0;
881
882 return attr->mode;
883 }
884
885 /* papr_scm specific dimm attributes */
886 static struct attribute *papr_nd_attributes[] = {
887 &dev_attr_flags.attr,
888 &dev_attr_perf_stats.attr,
889 NULL,
890 };
891
892 static struct attribute_group papr_nd_attribute_group = {
893 .name = "papr",
894 .is_visible = papr_nd_attribute_visible,
895 .attrs = papr_nd_attributes,
896 };
897
898 static const struct attribute_group *papr_nd_attr_groups[] = {
899 &papr_nd_attribute_group,
900 NULL,
901 };
902
papr_scm_nvdimm_init(struct papr_scm_priv * p)903 static int papr_scm_nvdimm_init(struct papr_scm_priv *p)
904 {
905 struct device *dev = &p->pdev->dev;
906 struct nd_mapping_desc mapping;
907 struct nd_region_desc ndr_desc;
908 unsigned long dimm_flags;
909 int target_nid, online_nid;
910
911 p->bus_desc.ndctl = papr_scm_ndctl;
912 p->bus_desc.module = THIS_MODULE;
913 p->bus_desc.of_node = p->pdev->dev.of_node;
914 p->bus_desc.provider_name = kstrdup(p->pdev->name, GFP_KERNEL);
915
916 /* Set the dimm command family mask to accept PDSMs */
917 set_bit(NVDIMM_FAMILY_PAPR, &p->bus_desc.dimm_family_mask);
918
919 if (!p->bus_desc.provider_name)
920 return -ENOMEM;
921
922 p->bus = nvdimm_bus_register(NULL, &p->bus_desc);
923 if (!p->bus) {
924 dev_err(dev, "Error creating nvdimm bus %pOF\n", p->dn);
925 kfree(p->bus_desc.provider_name);
926 return -ENXIO;
927 }
928
929 dimm_flags = 0;
930 set_bit(NDD_LABELING, &dimm_flags);
931
932 p->nvdimm = nvdimm_create(p->bus, p, papr_nd_attr_groups,
933 dimm_flags, PAPR_SCM_DIMM_CMD_MASK, 0, NULL);
934 if (!p->nvdimm) {
935 dev_err(dev, "Error creating DIMM object for %pOF\n", p->dn);
936 goto err;
937 }
938
939 if (nvdimm_bus_check_dimm_count(p->bus, 1))
940 goto err;
941
942 /* now add the region */
943
944 memset(&mapping, 0, sizeof(mapping));
945 mapping.nvdimm = p->nvdimm;
946 mapping.start = 0;
947 mapping.size = p->blocks * p->block_size; // XXX: potential overflow?
948
949 memset(&ndr_desc, 0, sizeof(ndr_desc));
950 target_nid = dev_to_node(&p->pdev->dev);
951 online_nid = numa_map_to_online_node(target_nid);
952 ndr_desc.numa_node = online_nid;
953 ndr_desc.target_node = target_nid;
954 ndr_desc.res = &p->res;
955 ndr_desc.of_node = p->dn;
956 ndr_desc.provider_data = p;
957 ndr_desc.mapping = &mapping;
958 ndr_desc.num_mappings = 1;
959 ndr_desc.nd_set = &p->nd_set;
960
961 if (p->is_volatile)
962 p->region = nvdimm_volatile_region_create(p->bus, &ndr_desc);
963 else {
964 set_bit(ND_REGION_PERSIST_MEMCTRL, &ndr_desc.flags);
965 p->region = nvdimm_pmem_region_create(p->bus, &ndr_desc);
966 }
967 if (!p->region) {
968 dev_err(dev, "Error registering region %pR from %pOF\n",
969 ndr_desc.res, p->dn);
970 goto err;
971 }
972 if (target_nid != online_nid)
973 dev_info(dev, "Region registered with target node %d and online node %d",
974 target_nid, online_nid);
975
976 mutex_lock(&papr_ndr_lock);
977 list_add_tail(&p->region_list, &papr_nd_regions);
978 mutex_unlock(&papr_ndr_lock);
979
980 return 0;
981
982 err: nvdimm_bus_unregister(p->bus);
983 kfree(p->bus_desc.provider_name);
984 return -ENXIO;
985 }
986
papr_scm_add_badblock(struct nd_region * region,struct nvdimm_bus * bus,u64 phys_addr)987 static void papr_scm_add_badblock(struct nd_region *region,
988 struct nvdimm_bus *bus, u64 phys_addr)
989 {
990 u64 aligned_addr = ALIGN_DOWN(phys_addr, L1_CACHE_BYTES);
991
992 if (nvdimm_bus_add_badrange(bus, aligned_addr, L1_CACHE_BYTES)) {
993 pr_err("Bad block registration for 0x%llx failed\n", phys_addr);
994 return;
995 }
996
997 pr_debug("Add memory range (0x%llx - 0x%llx) as bad range\n",
998 aligned_addr, aligned_addr + L1_CACHE_BYTES);
999
1000 nvdimm_region_notify(region, NVDIMM_REVALIDATE_POISON);
1001 }
1002
handle_mce_ue(struct notifier_block * nb,unsigned long val,void * data)1003 static int handle_mce_ue(struct notifier_block *nb, unsigned long val,
1004 void *data)
1005 {
1006 struct machine_check_event *evt = data;
1007 struct papr_scm_priv *p;
1008 u64 phys_addr;
1009 bool found = false;
1010
1011 if (evt->error_type != MCE_ERROR_TYPE_UE)
1012 return NOTIFY_DONE;
1013
1014 if (list_empty(&papr_nd_regions))
1015 return NOTIFY_DONE;
1016
1017 /*
1018 * The physical address obtained here is PAGE_SIZE aligned, so get the
1019 * exact address from the effective address
1020 */
1021 phys_addr = evt->u.ue_error.physical_address +
1022 (evt->u.ue_error.effective_address & ~PAGE_MASK);
1023
1024 if (!evt->u.ue_error.physical_address_provided ||
1025 !is_zone_device_page(pfn_to_page(phys_addr >> PAGE_SHIFT)))
1026 return NOTIFY_DONE;
1027
1028 /* mce notifier is called from a process context, so mutex is safe */
1029 mutex_lock(&papr_ndr_lock);
1030 list_for_each_entry(p, &papr_nd_regions, region_list) {
1031 if (phys_addr >= p->res.start && phys_addr <= p->res.end) {
1032 found = true;
1033 break;
1034 }
1035 }
1036
1037 if (found)
1038 papr_scm_add_badblock(p->region, p->bus, phys_addr);
1039
1040 mutex_unlock(&papr_ndr_lock);
1041
1042 return found ? NOTIFY_OK : NOTIFY_DONE;
1043 }
1044
1045 static struct notifier_block mce_ue_nb = {
1046 .notifier_call = handle_mce_ue
1047 };
1048
papr_scm_probe(struct platform_device * pdev)1049 static int papr_scm_probe(struct platform_device *pdev)
1050 {
1051 struct device_node *dn = pdev->dev.of_node;
1052 u32 drc_index, metadata_size;
1053 u64 blocks, block_size;
1054 struct papr_scm_priv *p;
1055 u8 uuid_raw[UUID_SIZE];
1056 const char *uuid_str;
1057 ssize_t stat_size;
1058 uuid_t uuid;
1059 int rc;
1060
1061 /* check we have all the required DT properties */
1062 if (of_property_read_u32(dn, "ibm,my-drc-index", &drc_index)) {
1063 dev_err(&pdev->dev, "%pOF: missing drc-index!\n", dn);
1064 return -ENODEV;
1065 }
1066
1067 if (of_property_read_u64(dn, "ibm,block-size", &block_size)) {
1068 dev_err(&pdev->dev, "%pOF: missing block-size!\n", dn);
1069 return -ENODEV;
1070 }
1071
1072 if (of_property_read_u64(dn, "ibm,number-of-blocks", &blocks)) {
1073 dev_err(&pdev->dev, "%pOF: missing number-of-blocks!\n", dn);
1074 return -ENODEV;
1075 }
1076
1077 if (of_property_read_string(dn, "ibm,unit-guid", &uuid_str)) {
1078 dev_err(&pdev->dev, "%pOF: missing unit-guid!\n", dn);
1079 return -ENODEV;
1080 }
1081
1082 /*
1083 * open firmware platform device create won't update the NUMA
1084 * distance table. For PAPR SCM devices we use numa_map_to_online_node()
1085 * to find the nearest online NUMA node and that requires correct
1086 * distance table information.
1087 */
1088 update_numa_distance(dn);
1089
1090 p = kzalloc(sizeof(*p), GFP_KERNEL);
1091 if (!p)
1092 return -ENOMEM;
1093
1094 /* Initialize the dimm mutex */
1095 mutex_init(&p->health_mutex);
1096
1097 /* optional DT properties */
1098 of_property_read_u32(dn, "ibm,metadata-size", &metadata_size);
1099
1100 p->dn = dn;
1101 p->drc_index = drc_index;
1102 p->block_size = block_size;
1103 p->blocks = blocks;
1104 p->is_volatile = !of_property_read_bool(dn, "ibm,cache-flush-required");
1105
1106 /* We just need to ensure that set cookies are unique across */
1107 uuid_parse(uuid_str, &uuid);
1108
1109 /*
1110 * The cookie1 and cookie2 are not really little endian.
1111 * We store a raw buffer representation of the
1112 * uuid string so that we can compare this with the label
1113 * area cookie irrespective of the endian configuration
1114 * with which the kernel is built.
1115 *
1116 * Historically we stored the cookie in the below format.
1117 * for a uuid string 72511b67-0b3b-42fd-8d1d-5be3cae8bcaa
1118 * cookie1 was 0xfd423b0b671b5172
1119 * cookie2 was 0xaabce8cae35b1d8d
1120 */
1121 export_uuid(uuid_raw, &uuid);
1122 p->nd_set.cookie1 = get_unaligned_le64(&uuid_raw[0]);
1123 p->nd_set.cookie2 = get_unaligned_le64(&uuid_raw[8]);
1124
1125 /* might be zero */
1126 p->metadata_size = metadata_size;
1127 p->pdev = pdev;
1128
1129 /* request the hypervisor to bind this region to somewhere in memory */
1130 rc = drc_pmem_bind(p);
1131
1132 /* If phyp says drc memory still bound then force unbound and retry */
1133 if (rc == H_OVERLAP)
1134 rc = drc_pmem_query_n_bind(p);
1135
1136 if (rc != H_SUCCESS) {
1137 dev_err(&p->pdev->dev, "bind err: %d\n", rc);
1138 rc = -ENXIO;
1139 goto err;
1140 }
1141
1142 /* setup the resource for the newly bound range */
1143 p->res.start = p->bound_addr;
1144 p->res.end = p->bound_addr + p->blocks * p->block_size - 1;
1145 p->res.name = pdev->name;
1146 p->res.flags = IORESOURCE_MEM;
1147
1148 /* Try retrieving the stat buffer and see if its supported */
1149 stat_size = drc_pmem_query_stats(p, NULL, 0);
1150 if (stat_size > 0) {
1151 p->stat_buffer_len = stat_size;
1152 dev_dbg(&p->pdev->dev, "Max perf-stat size %lu-bytes\n",
1153 p->stat_buffer_len);
1154 }
1155
1156 rc = papr_scm_nvdimm_init(p);
1157 if (rc)
1158 goto err2;
1159
1160 platform_set_drvdata(pdev, p);
1161
1162 return 0;
1163
1164 err2: drc_pmem_unbind(p);
1165 err: kfree(p);
1166 return rc;
1167 }
1168
papr_scm_remove(struct platform_device * pdev)1169 static int papr_scm_remove(struct platform_device *pdev)
1170 {
1171 struct papr_scm_priv *p = platform_get_drvdata(pdev);
1172
1173 mutex_lock(&papr_ndr_lock);
1174 list_del(&p->region_list);
1175 mutex_unlock(&papr_ndr_lock);
1176
1177 nvdimm_bus_unregister(p->bus);
1178 drc_pmem_unbind(p);
1179 kfree(p->bus_desc.provider_name);
1180 kfree(p);
1181
1182 return 0;
1183 }
1184
1185 static const struct of_device_id papr_scm_match[] = {
1186 { .compatible = "ibm,pmemory" },
1187 { .compatible = "ibm,pmemory-v2" },
1188 { },
1189 };
1190
1191 static struct platform_driver papr_scm_driver = {
1192 .probe = papr_scm_probe,
1193 .remove = papr_scm_remove,
1194 .driver = {
1195 .name = "papr_scm",
1196 .of_match_table = papr_scm_match,
1197 },
1198 };
1199
papr_scm_init(void)1200 static int __init papr_scm_init(void)
1201 {
1202 int ret;
1203
1204 ret = platform_driver_register(&papr_scm_driver);
1205 if (!ret)
1206 mce_register_notifier(&mce_ue_nb);
1207
1208 return ret;
1209 }
1210 module_init(papr_scm_init);
1211
papr_scm_exit(void)1212 static void __exit papr_scm_exit(void)
1213 {
1214 mce_unregister_notifier(&mce_ue_nb);
1215 platform_driver_unregister(&papr_scm_driver);
1216 }
1217 module_exit(papr_scm_exit);
1218
1219 MODULE_DEVICE_TABLE(of, papr_scm_match);
1220 MODULE_LICENSE("GPL");
1221 MODULE_AUTHOR("IBM Corporation");
1222