arch/powerpc/platforms/pseries/papr_scm.c

   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 #include <linux/perf_event.h>
  23
  24 #define BIND_ANY_ADDR (~0ul)
  25
  26 #define PAPR_SCM_DIMM_CMD_MASK \
  27         ((1ul << ND_CMD_GET_CONFIG_SIZE) | \
  28          (1ul << ND_CMD_GET_CONFIG_DATA) | \
  29          (1ul << ND_CMD_SET_CONFIG_DATA) | \
  30          (1ul << ND_CMD_CALL))
  31
  32 /* DIMM health bitmap bitmap indicators */
  33 /* SCM device is unable to persist memory contents */
  34 #define PAPR_PMEM_UNARMED                   (1ULL << (63 - 0))
  35 /* SCM device failed to persist memory contents */
  36 #define PAPR_PMEM_SHUTDOWN_DIRTY            (1ULL << (63 - 1))
  37 /* SCM device contents are persisted from previous IPL */
  38 #define PAPR_PMEM_SHUTDOWN_CLEAN            (1ULL << (63 - 2))
  39 /* SCM device contents are not persisted from previous IPL */
  40 #define PAPR_PMEM_EMPTY                     (1ULL << (63 - 3))
  41 /* SCM device memory life remaining is critically low */
  42 #define PAPR_PMEM_HEALTH_CRITICAL           (1ULL << (63 - 4))
  43 /* SCM device will be garded off next IPL due to failure */
  44 #define PAPR_PMEM_HEALTH_FATAL              (1ULL << (63 - 5))
  45 /* SCM contents cannot persist due to current platform health status */
  46 #define PAPR_PMEM_HEALTH_UNHEALTHY          (1ULL << (63 - 6))
  47 /* SCM device is unable to persist memory contents in certain conditions */
  48 #define PAPR_PMEM_HEALTH_NON_CRITICAL       (1ULL << (63 - 7))
  49 /* SCM device is encrypted */
  50 #define PAPR_PMEM_ENCRYPTED                 (1ULL << (63 - 8))
  51 /* SCM device has been scrubbed and locked */
  52 #define PAPR_PMEM_SCRUBBED_AND_LOCKED       (1ULL << (63 - 9))
  53
  54 /* Bits status indicators for health bitmap indicating unarmed dimm */
  55 #define PAPR_PMEM_UNARMED_MASK (PAPR_PMEM_UNARMED |             \
  56                                 PAPR_PMEM_HEALTH_UNHEALTHY)
  57
  58 /* Bits status indicators for health bitmap indicating unflushed dimm */
  59 #define PAPR_PMEM_BAD_SHUTDOWN_MASK (PAPR_PMEM_SHUTDOWN_DIRTY)
  60
  61 /* Bits status indicators for health bitmap indicating unrestored dimm */
  62 #define PAPR_PMEM_BAD_RESTORE_MASK  (PAPR_PMEM_EMPTY)
  63
  64 /* Bit status indicators for smart event notification */
  65 #define PAPR_PMEM_SMART_EVENT_MASK (PAPR_PMEM_HEALTH_CRITICAL | \
  66                                     PAPR_PMEM_HEALTH_FATAL |    \
  67                                     PAPR_PMEM_HEALTH_UNHEALTHY)
  68
  69 #define PAPR_SCM_PERF_STATS_EYECATCHER __stringify(SCMSTATS)
  70 #define PAPR_SCM_PERF_STATS_VERSION 0x1
  71
  72 /* Struct holding a single performance metric */
  73 struct papr_scm_perf_stat {
  74         u8 stat_id[8];
  75         __be64 stat_val;
  76 } __packed;
  77
  78 /* Struct exchanged between kernel and PHYP for fetching drc perf stats */
  79 struct papr_scm_perf_stats {
  80         u8 eye_catcher[8];
  81         /* Should be PAPR_SCM_PERF_STATS_VERSION */
  82         __be32 stats_version;
  83         /* Number of stats following */
  84         __be32 num_statistics;
  85         /* zero or more performance matrics */
  86         struct papr_scm_perf_stat scm_statistic[];
  87 } __packed;
  88
  89 /* private struct associated with each region */
  90 struct papr_scm_priv {
  91         struct platform_device *pdev;
  92         struct device_node *dn;
  93         uint32_t drc_index;
  94         uint64_t blocks;
  95         uint64_t block_size;
  96         int metadata_size;
  97         bool is_volatile;
  98         bool hcall_flush_required;
  99
 100         uint64_t bound_addr;
 101
 102         struct nvdimm_bus_descriptor bus_desc;
 103         struct nvdimm_bus *bus;
 104         struct nvdimm *nvdimm;
 105         struct resource res;
 106         struct nd_region *region;
 107         struct nd_interleave_set nd_set;
 108         struct list_head region_list;
 109
 110         /* Protect dimm health data from concurrent read/writes */
 111         struct mutex health_mutex;
 112
 113         /* Last time the health information of the dimm was updated */
 114         unsigned long lasthealth_jiffies;
 115
 116         /* Health information for the dimm */
 117         u64 health_bitmap;
 118
 119         /* Holds the last known dirty shutdown counter value */
 120         u64 dirty_shutdown_counter;
 121
 122         /* length of the stat buffer as expected by phyp */
 123         size_t stat_buffer_len;
 124
 125         /* The bits which needs to be overridden */
 126         u64 health_bitmap_inject_mask;
 127
 128         /* array to have event_code and stat_id mappings */
 129         u8 *nvdimm_events_map;
 130 };
 131
 132 static int papr_scm_pmem_flush(struct nd_region *nd_region,
 133                                struct bio *bio __maybe_unused)
 134 {
 135         struct papr_scm_priv *p = nd_region_provider_data(nd_region);
 136         unsigned long ret_buf[PLPAR_HCALL_BUFSIZE], token = 0;
 137         long rc;
 138
 139         dev_dbg(&p->pdev->dev, "flush drc 0x%x", p->drc_index);
 140
 141         do {
 142                 rc = plpar_hcall(H_SCM_FLUSH, ret_buf, p->drc_index, token);
 143                 token = ret_buf[0];
 144
 145                 /* Check if we are stalled for some time */
 146                 if (H_IS_LONG_BUSY(rc)) {
 147                         msleep(get_longbusy_msecs(rc));
 148                         rc = H_BUSY;
 149                 } else if (rc == H_BUSY) {
 150                         cond_resched();
 151                 }
 152         } while (rc == H_BUSY);
 153
 154         if (rc) {
 155                 dev_err(&p->pdev->dev, "flush error: %ld", rc);
 156                 rc = -EIO;
 157         } else {
 158                 dev_dbg(&p->pdev->dev, "flush drc 0x%x complete", p->drc_index);
 159         }
 160
 161         return rc;
 162 }
 163
 164 static LIST_HEAD(papr_nd_regions);
 165 static DEFINE_MUTEX(papr_ndr_lock);
 166
 167 static int drc_pmem_bind(struct papr_scm_priv *p)
 168 {
 169         unsigned long ret[PLPAR_HCALL_BUFSIZE];
 170         uint64_t saved = 0;
 171         uint64_t token;
 172         int64_t rc;
 173
 174         /*
 175          * When the hypervisor cannot map all the requested memory in a single
 176          * hcall it returns H_BUSY and we call again with the token until
 177          * we get H_SUCCESS. Aborting the retry loop before getting H_SUCCESS
 178          * leave the system in an undefined state, so we wait.
 179          */
 180         token = 0;
 181
 182         do {
 183                 rc = plpar_hcall(H_SCM_BIND_MEM, ret, p->drc_index, 0,
 184                                 p->blocks, BIND_ANY_ADDR, token);
 185                 token = ret[0];
 186                 if (!saved)
 187                         saved = ret[1];
 188                 cond_resched();
 189         } while (rc == H_BUSY);
 190
 191         if (rc)
 192                 return rc;
 193
 194         p->bound_addr = saved;
 195         dev_dbg(&p->pdev->dev, "bound drc 0x%x to 0x%lx\n",
 196                 p->drc_index, (unsigned long)saved);
 197         return rc;
 198 }
 199
 200 static void drc_pmem_unbind(struct papr_scm_priv *p)
 201 {
 202         unsigned long ret[PLPAR_HCALL_BUFSIZE];
 203         uint64_t token = 0;
 204         int64_t rc;
 205
 206         dev_dbg(&p->pdev->dev, "unbind drc 0x%x\n", p->drc_index);
 207
 208         /* NB: unbind has the same retry requirements as drc_pmem_bind() */
 209         do {
 210
 211                 /* Unbind of all SCM resources associated with drcIndex */
 212                 rc = plpar_hcall(H_SCM_UNBIND_ALL, ret, H_UNBIND_SCOPE_DRC,
 213                                  p->drc_index, token);
 214                 token = ret[0];
 215
 216                 /* Check if we are stalled for some time */
 217                 if (H_IS_LONG_BUSY(rc)) {
 218                         msleep(get_longbusy_msecs(rc));
 219                         rc = H_BUSY;
 220                 } else if (rc == H_BUSY) {
 221                         cond_resched();
 222                 }
 223
 224         } while (rc == H_BUSY);
 225
 226         if (rc)
 227                 dev_err(&p->pdev->dev, "unbind error: %lld\n", rc);
 228         else
 229                 dev_dbg(&p->pdev->dev, "unbind drc 0x%x complete\n",
 230                         p->drc_index);
 231
 232         return;
 233 }
 234
 235 static int drc_pmem_query_n_bind(struct papr_scm_priv *p)
 236 {
 237         unsigned long start_addr;
 238         unsigned long end_addr;
 239         unsigned long ret[PLPAR_HCALL_BUFSIZE];
 240         int64_t rc;
 241
 242
 243         rc = plpar_hcall(H_SCM_QUERY_BLOCK_MEM_BINDING, ret,
 244                          p->drc_index, 0);
 245         if (rc)
 246                 goto err_out;
 247         start_addr = ret[0];
 248
 249         /* Make sure the full region is bound. */
 250         rc = plpar_hcall(H_SCM_QUERY_BLOCK_MEM_BINDING, ret,
 251                          p->drc_index, p->blocks - 1);
 252         if (rc)
 253                 goto err_out;
 254         end_addr = ret[0];
 255
 256         if ((end_addr - start_addr) != ((p->blocks - 1) * p->block_size))
 257                 goto err_out;
 258
 259         p->bound_addr = start_addr;
 260         dev_dbg(&p->pdev->dev, "bound drc 0x%x to 0x%lx\n", p->drc_index, start_addr);
 261         return rc;
 262
 263 err_out:
 264         dev_info(&p->pdev->dev,
 265                  "Failed to query, trying an unbind followed by bind");
 266         drc_pmem_unbind(p);
 267         return drc_pmem_bind(p);
 268 }
 269
 270 /*
 271  * Query the Dimm performance stats from PHYP and copy them (if returned) to
 272  * provided struct papr_scm_perf_stats instance 'stats' that can hold atleast
 273  * (num_stats + header) bytes.
 274  * - If buff_stats == NULL the return value is the size in bytes of the buffer
 275  * needed to hold all supported performance-statistics.
 276  * - If buff_stats != NULL and num_stats == 0 then we copy all known
 277  * performance-statistics to 'buff_stat' and expect to be large enough to
 278  * hold them.
 279  * - if buff_stats != NULL and num_stats > 0 then copy the requested
 280  * performance-statistics to buff_stats.
 281  */
 282 static ssize_t drc_pmem_query_stats(struct papr_scm_priv *p,
 283                                     struct papr_scm_perf_stats *buff_stats,
 284                                     unsigned int num_stats)
 285 {
 286         unsigned long ret[PLPAR_HCALL_BUFSIZE];
 287         size_t size;
 288         s64 rc;
 289
 290         /* Setup the out buffer */
 291         if (buff_stats) {
 292                 memcpy(buff_stats->eye_catcher,
 293                        PAPR_SCM_PERF_STATS_EYECATCHER, 8);
 294                 buff_stats->stats_version =
 295                         cpu_to_be32(PAPR_SCM_PERF_STATS_VERSION);
 296                 buff_stats->num_statistics =
 297                         cpu_to_be32(num_stats);
 298
 299                 /*
 300                  * Calculate the buffer size based on num-stats provided
 301                  * or use the prefetched max buffer length
 302                  */
 303                 if (num_stats)
 304                         /* Calculate size from the num_stats */
 305                         size = sizeof(struct papr_scm_perf_stats) +
 306                                 num_stats * sizeof(struct papr_scm_perf_stat);
 307                 else
 308                         size = p->stat_buffer_len;
 309         } else {
 310                 /* In case of no out buffer ignore the size */
 311                 size = 0;
 312         }
 313
 314         /* Do the HCALL asking PHYP for info */
 315         rc = plpar_hcall(H_SCM_PERFORMANCE_STATS, ret, p->drc_index,
 316                          buff_stats ? virt_to_phys(buff_stats) : 0,
 317                          size);
 318
 319         /* Check if the error was due to an unknown stat-id */
 320         if (rc == H_PARTIAL) {
 321                 dev_err(&p->pdev->dev,
 322                         "Unknown performance stats, Err:0x%016lX\n", ret[0]);
 323                 return -ENOENT;
 324         } else if (rc == H_AUTHORITY) {
 325                 dev_info(&p->pdev->dev,
 326                          "Permission denied while accessing performance stats");
 327                 return -EPERM;
 328         } else if (rc == H_UNSUPPORTED) {
 329                 dev_dbg(&p->pdev->dev, "Performance stats unsupported\n");
 330                 return -EOPNOTSUPP;
 331         } else if (rc != H_SUCCESS) {
 332                 dev_err(&p->pdev->dev,
 333                         "Failed to query performance stats, Err:%lld\n", rc);
 334                 return -EIO;
 335
 336         } else if (!size) {
 337                 /* Handle case where stat buffer size was requested */
 338                 dev_dbg(&p->pdev->dev,
 339                         "Performance stats size %ld\n", ret[0]);
 340                 return ret[0];
 341         }
 342
 343         /* Successfully fetched the requested stats from phyp */
 344         dev_dbg(&p->pdev->dev,
 345                 "Performance stats returned %d stats\n",
 346                 be32_to_cpu(buff_stats->num_statistics));
 347         return 0;
 348 }
 349
 350 #ifdef CONFIG_PERF_EVENTS
 351 #define to_nvdimm_pmu(_pmu)     container_of(_pmu, struct nvdimm_pmu, pmu)
 352
 353 static int papr_scm_pmu_get_value(struct perf_event *event, struct device *dev, u64 *count)
 354 {
 355         struct papr_scm_perf_stat *stat;
 356         struct papr_scm_perf_stats *stats;
 357         struct papr_scm_priv *p = (struct papr_scm_priv *)dev->driver_data;
 358         int rc, size;
 359
 360         /* Allocate request buffer enough to hold single performance stat */
 361         size = sizeof(struct papr_scm_perf_stats) +
 362                 sizeof(struct papr_scm_perf_stat);
 363
 364         if (!p || !p->nvdimm_events_map)
 365                 return -EINVAL;
 366
 367         stats = kzalloc(size, GFP_KERNEL);
 368         if (!stats)
 369                 return -ENOMEM;
 370
 371         stat = &stats->scm_statistic[0];
 372         memcpy(&stat->stat_id,
 373                &p->nvdimm_events_map[event->attr.config * sizeof(stat->stat_id)],
 374                 sizeof(stat->stat_id));
 375         stat->stat_val = 0;
 376
 377         rc = drc_pmem_query_stats(p, stats, 1);
 378         if (rc < 0) {
 379                 kfree(stats);
 380                 return rc;
 381         }
 382
 383         *count = be64_to_cpu(stat->stat_val);
 384         kfree(stats);
 385         return 0;
 386 }
 387
 388 static int papr_scm_pmu_event_init(struct perf_event *event)
 389 {
 390         struct nvdimm_pmu *nd_pmu = to_nvdimm_pmu(event->pmu);
 391         struct papr_scm_priv *p;
 392
 393         if (!nd_pmu)
 394                 return -EINVAL;
 395
 396         /* test the event attr type for PMU enumeration */
 397         if (event->attr.type != event->pmu->type)
 398                 return -ENOENT;
 399
 400         /* it does not support event sampling mode */
 401         if (is_sampling_event(event))
 402                 return -EOPNOTSUPP;
 403
 404         /* no branch sampling */
 405         if (has_branch_stack(event))
 406                 return -EOPNOTSUPP;
 407
 408         p = (struct papr_scm_priv *)nd_pmu->dev->driver_data;
 409         if (!p)
 410                 return -EINVAL;
 411
 412         /* Invalid eventcode */
 413         if (event->attr.config == 0 || event->attr.config > 16)
 414                 return -EINVAL;
 415
 416         return 0;
 417 }
 418
 419 static int papr_scm_pmu_add(struct perf_event *event, int flags)
 420 {
 421         u64 count;
 422         int rc;
 423         struct nvdimm_pmu *nd_pmu = to_nvdimm_pmu(event->pmu);
 424
 425         if (!nd_pmu)
 426                 return -EINVAL;
 427
 428         if (flags & PERF_EF_START) {
 429                 rc = papr_scm_pmu_get_value(event, nd_pmu->dev, &count);
 430                 if (rc)
 431                         return rc;
 432
 433                 local64_set(&event->hw.prev_count, count);
 434         }
 435
 436         return 0;
 437 }
 438
 439 static void papr_scm_pmu_read(struct perf_event *event)
 440 {
 441         u64 prev, now;
 442         int rc;
 443         struct nvdimm_pmu *nd_pmu = to_nvdimm_pmu(event->pmu);
 444
 445         if (!nd_pmu)
 446                 return;
 447
 448         rc = papr_scm_pmu_get_value(event, nd_pmu->dev, &now);
 449         if (rc)
 450                 return;
 451
 452         prev = local64_xchg(&event->hw.prev_count, now);
 453         local64_add(now - prev, &event->count);
 454 }
 455
 456 static void papr_scm_pmu_del(struct perf_event *event, int flags)
 457 {
 458         papr_scm_pmu_read(event);
 459 }
 460
 461 static int papr_scm_pmu_check_events(struct papr_scm_priv *p, struct nvdimm_pmu *nd_pmu)
 462 {
 463         struct papr_scm_perf_stat *stat;
 464         struct papr_scm_perf_stats *stats;
 465         u32 available_events;
 466         int index, rc = 0;
 467
 468         if (!p->stat_buffer_len)
 469                 return -ENOENT;
 470
 471         available_events = (p->stat_buffer_len  - sizeof(struct papr_scm_perf_stats))
 472                         / sizeof(struct papr_scm_perf_stat);
 473         if (available_events == 0)
 474                 return -EOPNOTSUPP;
 475
 476         /* Allocate the buffer for phyp where stats are written */
 477         stats = kzalloc(p->stat_buffer_len, GFP_KERNEL);
 478         if (!stats) {
 479                 rc = -ENOMEM;
 480                 return rc;
 481         }
 482
 483         /* Called to get list of events supported */
 484         rc = drc_pmem_query_stats(p, stats, 0);
 485         if (rc)
 486                 goto out;
 487
 488         /*
 489          * Allocate memory and populate nvdimm_event_map.
 490          * Allocate an extra element for NULL entry
 491          */
 492         p->nvdimm_events_map = kcalloc(available_events + 1,
 493                                        sizeof(stat->stat_id),
 494                                        GFP_KERNEL);
 495         if (!p->nvdimm_events_map) {
 496                 rc = -ENOMEM;
 497                 goto out;
 498         }
 499
 500         /* Copy all stat_ids to event map */
 501         for (index = 0, stat = stats->scm_statistic;
 502              index < available_events; index++, ++stat) {
 503                 memcpy(&p->nvdimm_events_map[index * sizeof(stat->stat_id)],
 504                        &stat->stat_id, sizeof(stat->stat_id));
 505         }
 506 out:
 507         kfree(stats);
 508         return rc;
 509 }
 510
 511 static void papr_scm_pmu_register(struct papr_scm_priv *p)
 512 {
 513         struct nvdimm_pmu *nd_pmu;
 514         int rc, nodeid;
 515
 516         nd_pmu = kzalloc(sizeof(*nd_pmu), GFP_KERNEL);
 517         if (!nd_pmu) {
 518                 rc = -ENOMEM;
 519                 goto pmu_err_print;
 520         }
 521
 522         rc = papr_scm_pmu_check_events(p, nd_pmu);
 523         if (rc)
 524                 goto pmu_check_events_err;
 525
 526         nd_pmu->pmu.task_ctx_nr = perf_invalid_context;
 527         nd_pmu->pmu.name = nvdimm_name(p->nvdimm);
 528         nd_pmu->pmu.event_init = papr_scm_pmu_event_init;
 529         nd_pmu->pmu.read = papr_scm_pmu_read;
 530         nd_pmu->pmu.add = papr_scm_pmu_add;
 531         nd_pmu->pmu.del = papr_scm_pmu_del;
 532
 533         nd_pmu->pmu.capabilities = PERF_PMU_CAP_NO_INTERRUPT |
 534                                 PERF_PMU_CAP_NO_EXCLUDE;
 535
 536         /*updating the cpumask variable */
 537         nodeid = numa_map_to_online_node(dev_to_node(&p->pdev->dev));
 538         nd_pmu->arch_cpumask = *cpumask_of_node(nodeid);
 539
 540         rc = register_nvdimm_pmu(nd_pmu, p->pdev);
 541         if (rc)
 542                 goto pmu_register_err;
 543
 544         /*
 545          * Set archdata.priv value to nvdimm_pmu structure, to handle the
 546          * unregistering of pmu device.
 547          */
 548         p->pdev->archdata.priv = nd_pmu;
 549         return;
 550
 551 pmu_register_err:
 552         kfree(p->nvdimm_events_map);
 553 pmu_check_events_err:
 554         kfree(nd_pmu);
 555 pmu_err_print:
 556         dev_info(&p->pdev->dev, "nvdimm pmu didn't register rc=%d\n", rc);
 557 }
 558
 559 #else
 560 static void papr_scm_pmu_register(struct papr_scm_priv *p) { }
 561 #endif
 562
 563 /*
 564  * Issue hcall to retrieve dimm health info and populate papr_scm_priv with the
 565  * health information.
 566  */
 567 static int __drc_pmem_query_health(struct papr_scm_priv *p)
 568 {
 569         unsigned long ret[PLPAR_HCALL_BUFSIZE];
 570         u64 bitmap = 0;
 571         long rc;
 572
 573         /* issue the hcall */
 574         rc = plpar_hcall(H_SCM_HEALTH, ret, p->drc_index);
 575         if (rc == H_SUCCESS)
 576                 bitmap = ret[0] & ret[1];
 577         else if (rc == H_FUNCTION)
 578                 dev_info_once(&p->pdev->dev,
 579                               "Hcall H_SCM_HEALTH not implemented, assuming empty health bitmap");
 580         else {
 581
 582                 dev_err(&p->pdev->dev,
 583                         "Failed to query health information, Err:%ld\n", rc);
 584                 return -ENXIO;
 585         }
 586
 587         p->lasthealth_jiffies = jiffies;
 588         /* Allow injecting specific health bits via inject mask. */
 589         if (p->health_bitmap_inject_mask)
 590                 bitmap = (bitmap & ~p->health_bitmap_inject_mask) |
 591                         p->health_bitmap_inject_mask;
 592         WRITE_ONCE(p->health_bitmap, bitmap);
 593         dev_dbg(&p->pdev->dev,
 594                 "Queried dimm health info. Bitmap:0x%016lx Mask:0x%016lx\n",
 595                 ret[0], ret[1]);
 596
 597         return 0;
 598 }
 599
 600 /* Min interval in seconds for assuming stable dimm health */
 601 #define MIN_HEALTH_QUERY_INTERVAL 60
 602
 603 /* Query cached health info and if needed call drc_pmem_query_health */
 604 static int drc_pmem_query_health(struct papr_scm_priv *p)
 605 {
 606         unsigned long cache_timeout;
 607         int rc;
 608
 609         /* Protect concurrent modifications to papr_scm_priv */
 610         rc = mutex_lock_interruptible(&p->health_mutex);
 611         if (rc)
 612                 return rc;
 613
 614         /* Jiffies offset for which the health data is assumed to be same */
 615         cache_timeout = p->lasthealth_jiffies +
 616                 msecs_to_jiffies(MIN_HEALTH_QUERY_INTERVAL * 1000);
 617
 618         /* Fetch new health info is its older than MIN_HEALTH_QUERY_INTERVAL */
 619         if (time_after(jiffies, cache_timeout))
 620                 rc = __drc_pmem_query_health(p);
 621         else
 622                 /* Assume cached health data is valid */
 623                 rc = 0;
 624
 625         mutex_unlock(&p->health_mutex);
 626         return rc;
 627 }
 628
 629 static int papr_scm_meta_get(struct papr_scm_priv *p,
 630                              struct nd_cmd_get_config_data_hdr *hdr)
 631 {
 632         unsigned long data[PLPAR_HCALL_BUFSIZE];
 633         unsigned long offset, data_offset;
 634         int len, read;
 635         int64_t ret;
 636
 637         if ((hdr->in_offset + hdr->in_length) > p->metadata_size)
 638                 return -EINVAL;
 639
 640         for (len = hdr->in_length; len; len -= read) {
 641
 642                 data_offset = hdr->in_length - len;
 643                 offset = hdr->in_offset + data_offset;
 644
 645                 if (len >= 8)
 646                         read = 8;
 647                 else if (len >= 4)
 648                         read = 4;
 649                 else if (len >= 2)
 650                         read = 2;
 651                 else
 652                         read = 1;
 653
 654                 ret = plpar_hcall(H_SCM_READ_METADATA, data, p->drc_index,
 655                                   offset, read);
 656
 657                 if (ret == H_PARAMETER) /* bad DRC index */
 658                         return -ENODEV;
 659                 if (ret)
 660                         return -EINVAL; /* other invalid parameter */
 661
 662                 switch (read) {
 663                 case 8:
 664                         *(uint64_t *)(hdr->out_buf + data_offset) = be64_to_cpu(data[0]);
 665                         break;
 666                 case 4:
 667                         *(uint32_t *)(hdr->out_buf + data_offset) = be32_to_cpu(data[0] & 0xffffffff);
 668                         break;
 669
 670                 case 2:
 671                         *(uint16_t *)(hdr->out_buf + data_offset) = be16_to_cpu(data[0] & 0xffff);
 672                         break;
 673
 674                 case 1:
 675                         *(uint8_t *)(hdr->out_buf + data_offset) = (data[0] & 0xff);
 676                         break;
 677                 }
 678         }
 679         return 0;
 680 }
 681
 682 static int papr_scm_meta_set(struct papr_scm_priv *p,
 683                              struct nd_cmd_set_config_hdr *hdr)
 684 {
 685         unsigned long offset, data_offset;
 686         int len, wrote;
 687         unsigned long data;
 688         __be64 data_be;
 689         int64_t ret;
 690
 691         if ((hdr->in_offset + hdr->in_length) > p->metadata_size)
 692                 return -EINVAL;
 693
 694         for (len = hdr->in_length; len; len -= wrote) {
 695
 696                 data_offset = hdr->in_length - len;
 697                 offset = hdr->in_offset + data_offset;
 698
 699                 if (len >= 8) {
 700                         data = *(uint64_t *)(hdr->in_buf + data_offset);
 701                         data_be = cpu_to_be64(data);
 702                         wrote = 8;
 703                 } else if (len >= 4) {
 704                         data = *(uint32_t *)(hdr->in_buf + data_offset);
 705                         data &= 0xffffffff;
 706                         data_be = cpu_to_be32(data);
 707                         wrote = 4;
 708                 } else if (len >= 2) {
 709                         data = *(uint16_t *)(hdr->in_buf + data_offset);
 710                         data &= 0xffff;
 711                         data_be = cpu_to_be16(data);
 712                         wrote = 2;
 713                 } else {
 714                         data_be = *(uint8_t *)(hdr->in_buf + data_offset);
 715                         data_be &= 0xff;
 716                         wrote = 1;
 717                 }
 718
 719                 ret = plpar_hcall_norets(H_SCM_WRITE_METADATA, p->drc_index,
 720                                          offset, data_be, wrote);
 721                 if (ret == H_PARAMETER) /* bad DRC index */
 722                         return -ENODEV;
 723                 if (ret)
 724                         return -EINVAL; /* other invalid parameter */
 725         }
 726
 727         return 0;
 728 }
 729
 730 /*
 731  * Do a sanity checks on the inputs args to dimm-control function and return
 732  * '0' if valid. Validation of PDSM payloads happens later in
 733  * papr_scm_service_pdsm.
 734  */
 735 static int is_cmd_valid(struct nvdimm *nvdimm, unsigned int cmd, void *buf,
 736                         unsigned int buf_len)
 737 {
 738         unsigned long cmd_mask = PAPR_SCM_DIMM_CMD_MASK;
 739         struct nd_cmd_pkg *nd_cmd;
 740         struct papr_scm_priv *p;
 741         enum papr_pdsm pdsm;
 742
 743         /* Only dimm-specific calls are supported atm */
 744         if (!nvdimm)
 745                 return -EINVAL;
 746
 747         /* get the provider data from struct nvdimm */
 748         p = nvdimm_provider_data(nvdimm);
 749
 750         if (!test_bit(cmd, &cmd_mask)) {
 751                 dev_dbg(&p->pdev->dev, "Unsupported cmd=%u\n", cmd);
 752                 return -EINVAL;
 753         }
 754
 755         /* For CMD_CALL verify pdsm request */
 756         if (cmd == ND_CMD_CALL) {
 757                 /* Verify the envelope and envelop size */
 758                 if (!buf ||
 759                     buf_len < (sizeof(struct nd_cmd_pkg) + ND_PDSM_HDR_SIZE)) {
 760                         dev_dbg(&p->pdev->dev, "Invalid pkg size=%u\n",
 761                                 buf_len);
 762                         return -EINVAL;
 763                 }
 764
 765                 /* Verify that the nd_cmd_pkg.nd_family is correct */
 766                 nd_cmd = (struct nd_cmd_pkg *)buf;
 767
 768                 if (nd_cmd->nd_family != NVDIMM_FAMILY_PAPR) {
 769                         dev_dbg(&p->pdev->dev, "Invalid pkg family=0x%llx\n",
 770                                 nd_cmd->nd_family);
 771                         return -EINVAL;
 772                 }
 773
 774                 pdsm = (enum papr_pdsm)nd_cmd->nd_command;
 775
 776                 /* Verify if the pdsm command is valid */
 777                 if (pdsm <= PAPR_PDSM_MIN || pdsm >= PAPR_PDSM_MAX) {
 778                         dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Invalid PDSM\n",
 779                                 pdsm);
 780                         return -EINVAL;
 781                 }
 782
 783                 /* Have enough space to hold returned 'nd_pkg_pdsm' header */
 784                 if (nd_cmd->nd_size_out < ND_PDSM_HDR_SIZE) {
 785                         dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Invalid payload\n",
 786                                 pdsm);
 787                         return -EINVAL;
 788                 }
 789         }
 790
 791         /* Let the command be further processed */
 792         return 0;
 793 }
 794
 795 static int papr_pdsm_fuel_gauge(struct papr_scm_priv *p,
 796                                 union nd_pdsm_payload *payload)
 797 {
 798         int rc, size;
 799         u64 statval;
 800         struct papr_scm_perf_stat *stat;
 801         struct papr_scm_perf_stats *stats;
 802
 803         /* Silently fail if fetching performance metrics isn't  supported */
 804         if (!p->stat_buffer_len)
 805                 return 0;
 806
 807         /* Allocate request buffer enough to hold single performance stat */
 808         size = sizeof(struct papr_scm_perf_stats) +
 809                 sizeof(struct papr_scm_perf_stat);
 810
 811         stats = kzalloc(size, GFP_KERNEL);
 812         if (!stats)
 813                 return -ENOMEM;
 814
 815         stat = &stats->scm_statistic[0];
 816         memcpy(&stat->stat_id, "MemLife ", sizeof(stat->stat_id));
 817         stat->stat_val = 0;
 818
 819         /* Fetch the fuel gauge and populate it in payload */
 820         rc = drc_pmem_query_stats(p, stats, 1);
 821         if (rc < 0) {
 822                 dev_dbg(&p->pdev->dev, "Err(%d) fetching fuel gauge\n", rc);
 823                 goto free_stats;
 824         }
 825
 826         statval = be64_to_cpu(stat->stat_val);
 827         dev_dbg(&p->pdev->dev,
 828                 "Fetched fuel-gauge %llu", statval);
 829         payload->health.extension_flags |=
 830                 PDSM_DIMM_HEALTH_RUN_GAUGE_VALID;
 831         payload->health.dimm_fuel_gauge = statval;
 832
 833         rc = sizeof(struct nd_papr_pdsm_health);
 834
 835 free_stats:
 836         kfree(stats);
 837         return rc;
 838 }
 839
 840 /* Add the dirty-shutdown-counter value to the pdsm */
 841 static int papr_pdsm_dsc(struct papr_scm_priv *p,
 842                          union nd_pdsm_payload *payload)
 843 {
 844         payload->health.extension_flags |= PDSM_DIMM_DSC_VALID;
 845         payload->health.dimm_dsc = p->dirty_shutdown_counter;
 846
 847         return sizeof(struct nd_papr_pdsm_health);
 848 }
 849
 850 /* Fetch the DIMM health info and populate it in provided package. */
 851 static int papr_pdsm_health(struct papr_scm_priv *p,
 852                             union nd_pdsm_payload *payload)
 853 {
 854         int rc;
 855
 856         /* Ensure dimm health mutex is taken preventing concurrent access */
 857         rc = mutex_lock_interruptible(&p->health_mutex);
 858         if (rc)
 859                 goto out;
 860
 861         /* Always fetch upto date dimm health data ignoring cached values */
 862         rc = __drc_pmem_query_health(p);
 863         if (rc) {
 864                 mutex_unlock(&p->health_mutex);
 865                 goto out;
 866         }
 867
 868         /* update health struct with various flags derived from health bitmap */
 869         payload->health = (struct nd_papr_pdsm_health) {
 870                 .extension_flags = 0,
 871                 .dimm_unarmed = !!(p->health_bitmap & PAPR_PMEM_UNARMED_MASK),
 872                 .dimm_bad_shutdown = !!(p->health_bitmap & PAPR_PMEM_BAD_SHUTDOWN_MASK),
 873                 .dimm_bad_restore = !!(p->health_bitmap & PAPR_PMEM_BAD_RESTORE_MASK),
 874                 .dimm_scrubbed = !!(p->health_bitmap & PAPR_PMEM_SCRUBBED_AND_LOCKED),
 875                 .dimm_locked = !!(p->health_bitmap & PAPR_PMEM_SCRUBBED_AND_LOCKED),
 876                 .dimm_encrypted = !!(p->health_bitmap & PAPR_PMEM_ENCRYPTED),
 877                 .dimm_health = PAPR_PDSM_DIMM_HEALTHY,
 878         };
 879
 880         /* Update field dimm_health based on health_bitmap flags */
 881         if (p->health_bitmap & PAPR_PMEM_HEALTH_FATAL)
 882                 payload->health.dimm_health = PAPR_PDSM_DIMM_FATAL;
 883         else if (p->health_bitmap & PAPR_PMEM_HEALTH_CRITICAL)
 884                 payload->health.dimm_health = PAPR_PDSM_DIMM_CRITICAL;
 885         else if (p->health_bitmap & PAPR_PMEM_HEALTH_UNHEALTHY)
 886                 payload->health.dimm_health = PAPR_PDSM_DIMM_UNHEALTHY;
 887
 888         /* struct populated hence can release the mutex now */
 889         mutex_unlock(&p->health_mutex);
 890
 891         /* Populate the fuel gauge meter in the payload */
 892         papr_pdsm_fuel_gauge(p, payload);
 893         /* Populate the dirty-shutdown-counter field */
 894         papr_pdsm_dsc(p, payload);
 895
 896         rc = sizeof(struct nd_papr_pdsm_health);
 897
 898 out:
 899         return rc;
 900 }
 901
 902 /* Inject a smart error Add the dirty-shutdown-counter value to the pdsm */
 903 static int papr_pdsm_smart_inject(struct papr_scm_priv *p,
 904                                   union nd_pdsm_payload *payload)
 905 {
 906         int rc;
 907         u32 supported_flags = 0;
 908         u64 inject_mask = 0, clear_mask = 0;
 909         u64 mask;
 910
 911         /* Check for individual smart error flags and update inject/clear masks */
 912         if (payload->smart_inject.flags & PDSM_SMART_INJECT_HEALTH_FATAL) {
 913                 supported_flags |= PDSM_SMART_INJECT_HEALTH_FATAL;
 914                 if (payload->smart_inject.fatal_enable)
 915                         inject_mask |= PAPR_PMEM_HEALTH_FATAL;
 916                 else
 917                         clear_mask |= PAPR_PMEM_HEALTH_FATAL;
 918         }
 919
 920         if (payload->smart_inject.flags & PDSM_SMART_INJECT_BAD_SHUTDOWN) {
 921                 supported_flags |= PDSM_SMART_INJECT_BAD_SHUTDOWN;
 922                 if (payload->smart_inject.unsafe_shutdown_enable)
 923                         inject_mask |= PAPR_PMEM_SHUTDOWN_DIRTY;
 924                 else
 925                         clear_mask |= PAPR_PMEM_SHUTDOWN_DIRTY;
 926         }
 927
 928         dev_dbg(&p->pdev->dev, "[Smart-inject] inject_mask=%#llx clear_mask=%#llx\n",
 929                 inject_mask, clear_mask);
 930
 931         /* Prevent concurrent access to dimm health bitmap related members */
 932         rc = mutex_lock_interruptible(&p->health_mutex);
 933         if (rc)
 934                 return rc;
 935
 936         /* Use inject/clear masks to set health_bitmap_inject_mask */
 937         mask = READ_ONCE(p->health_bitmap_inject_mask);
 938         mask = (mask & ~clear_mask) | inject_mask;
 939         WRITE_ONCE(p->health_bitmap_inject_mask, mask);
 940
 941         /* Invalidate cached health bitmap */
 942         p->lasthealth_jiffies = 0;
 943
 944         mutex_unlock(&p->health_mutex);
 945
 946         /* Return the supported flags back to userspace */
 947         payload->smart_inject.flags = supported_flags;
 948
 949         return sizeof(struct nd_papr_pdsm_health);
 950 }
 951
 952 /*
 953  * 'struct pdsm_cmd_desc'
 954  * Identifies supported PDSMs' expected length of in/out payloads
 955  * and pdsm service function.
 956  *
 957  * size_in      : Size of input payload if any in the PDSM request.
 958  * size_out     : Size of output payload if any in the PDSM request.
 959  * service      : Service function for the PDSM request. Return semantics:
 960  *                rc < 0 : Error servicing PDSM and rc indicates the error.
 961  *                rc >=0 : Serviced successfully and 'rc' indicate number of
 962  *                      bytes written to payload.
 963  */
 964 struct pdsm_cmd_desc {
 965         u32 size_in;
 966         u32 size_out;
 967         int (*service)(struct papr_scm_priv *dimm,
 968                        union nd_pdsm_payload *payload);
 969 };
 970
 971 /* Holds all supported PDSMs' command descriptors */
 972 static const struct pdsm_cmd_desc __pdsm_cmd_descriptors[] = {
 973         [PAPR_PDSM_MIN] = {
 974                 .size_in = 0,
 975                 .size_out = 0,
 976                 .service = NULL,
 977         },
 978         /* New PDSM command descriptors to be added below */
 979
 980         [PAPR_PDSM_HEALTH] = {
 981                 .size_in = 0,
 982                 .size_out = sizeof(struct nd_papr_pdsm_health),
 983                 .service = papr_pdsm_health,
 984         },
 985
 986         [PAPR_PDSM_SMART_INJECT] = {
 987                 .size_in = sizeof(struct nd_papr_pdsm_smart_inject),
 988                 .size_out = sizeof(struct nd_papr_pdsm_smart_inject),
 989                 .service = papr_pdsm_smart_inject,
 990         },
 991         /* Empty */
 992         [PAPR_PDSM_MAX] = {
 993                 .size_in = 0,
 994                 .size_out = 0,
 995                 .service = NULL,
 996         },
 997 };
 998
 999 /* Given a valid pdsm cmd return its command descriptor else return NULL */
1000 static inline const struct pdsm_cmd_desc *pdsm_cmd_desc(enum papr_pdsm cmd)
1001 {
1002         if (cmd >= 0 || cmd < ARRAY_SIZE(__pdsm_cmd_descriptors))
1003                 return &__pdsm_cmd_descriptors[cmd];
1004
1005         return NULL;
1006 }
1007
1008 /*
1009  * For a given pdsm request call an appropriate service function.
1010  * Returns errors if any while handling the pdsm command package.
1011  */
1012 static int papr_scm_service_pdsm(struct papr_scm_priv *p,
1013                                  struct nd_cmd_pkg *pkg)
1014 {
1015         /* Get the PDSM header and PDSM command */
1016         struct nd_pkg_pdsm *pdsm_pkg = (struct nd_pkg_pdsm *)pkg->nd_payload;
1017         enum papr_pdsm pdsm = (enum papr_pdsm)pkg->nd_command;
1018         const struct pdsm_cmd_desc *pdsc;
1019         int rc;
1020
1021         /* Fetch corresponding pdsm descriptor for validation and servicing */
1022         pdsc = pdsm_cmd_desc(pdsm);
1023
1024         /* Validate pdsm descriptor */
1025         /* Ensure that reserved fields are 0 */
1026         if (pdsm_pkg->reserved[0] || pdsm_pkg->reserved[1]) {
1027                 dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Invalid reserved field\n",
1028                         pdsm);
1029                 return -EINVAL;
1030         }
1031
1032         /* If pdsm expects some input, then ensure that the size_in matches */
1033         if (pdsc->size_in &&
1034             pkg->nd_size_in != (pdsc->size_in + ND_PDSM_HDR_SIZE)) {
1035                 dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Mismatched size_in=%d\n",
1036                         pdsm, pkg->nd_size_in);
1037                 return -EINVAL;
1038         }
1039
1040         /* If pdsm wants to return data, then ensure that  size_out matches */
1041         if (pdsc->size_out &&
1042             pkg->nd_size_out != (pdsc->size_out + ND_PDSM_HDR_SIZE)) {
1043                 dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Mismatched size_out=%d\n",
1044                         pdsm, pkg->nd_size_out);
1045                 return -EINVAL;
1046         }
1047
1048         /* Service the pdsm */
1049         if (pdsc->service) {
1050                 dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Servicing..\n", pdsm);
1051
1052                 rc = pdsc->service(p, &pdsm_pkg->payload);
1053
1054                 if (rc < 0) {
1055                         /* error encountered while servicing pdsm */
1056                         pdsm_pkg->cmd_status = rc;
1057                         pkg->nd_fw_size = ND_PDSM_HDR_SIZE;
1058                 } else {
1059                         /* pdsm serviced and 'rc' bytes written to payload */
1060                         pdsm_pkg->cmd_status = 0;
1061                         pkg->nd_fw_size = ND_PDSM_HDR_SIZE + rc;
1062                 }
1063         } else {
1064                 dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Unsupported PDSM request\n",
1065                         pdsm);
1066                 pdsm_pkg->cmd_status = -ENOENT;
1067                 pkg->nd_fw_size = ND_PDSM_HDR_SIZE;
1068         }
1069
1070         return pdsm_pkg->cmd_status;
1071 }
1072
1073 static int papr_scm_ndctl(struct nvdimm_bus_descriptor *nd_desc,
1074                           struct nvdimm *nvdimm, unsigned int cmd, void *buf,
1075                           unsigned int buf_len, int *cmd_rc)
1076 {
1077         struct nd_cmd_get_config_size *get_size_hdr;
1078         struct nd_cmd_pkg *call_pkg = NULL;
1079         struct papr_scm_priv *p;
1080         int rc;
1081
1082         rc = is_cmd_valid(nvdimm, cmd, buf, buf_len);
1083         if (rc) {
1084                 pr_debug("Invalid cmd=0x%x. Err=%d\n", cmd, rc);
1085                 return rc;
1086         }
1087
1088         /* Use a local variable in case cmd_rc pointer is NULL */
1089         if (!cmd_rc)
1090                 cmd_rc = &rc;
1091
1092         p = nvdimm_provider_data(nvdimm);
1093
1094         switch (cmd) {
1095         case ND_CMD_GET_CONFIG_SIZE:
1096                 get_size_hdr = buf;
1097
1098                 get_size_hdr->status = 0;
1099                 get_size_hdr->max_xfer = 8;
1100                 get_size_hdr->config_size = p->metadata_size;
1101                 *cmd_rc = 0;
1102                 break;
1103
1104         case ND_CMD_GET_CONFIG_DATA:
1105                 *cmd_rc = papr_scm_meta_get(p, buf);
1106                 break;
1107
1108         case ND_CMD_SET_CONFIG_DATA:
1109                 *cmd_rc = papr_scm_meta_set(p, buf);
1110                 break;
1111
1112         case ND_CMD_CALL:
1113                 call_pkg = (struct nd_cmd_pkg *)buf;
1114                 *cmd_rc = papr_scm_service_pdsm(p, call_pkg);
1115                 break;
1116
1117         default:
1118                 dev_dbg(&p->pdev->dev, "Unknown command = %d\n", cmd);
1119                 return -EINVAL;
1120         }
1121
1122         dev_dbg(&p->pdev->dev, "returned with cmd_rc = %d\n", *cmd_rc);
1123
1124         return 0;
1125 }
1126
1127 static ssize_t health_bitmap_inject_show(struct device *dev,
1128                                          struct device_attribute *attr,
1129                                          char *buf)
1130 {
1131         struct nvdimm *dimm = to_nvdimm(dev);
1132         struct papr_scm_priv *p = nvdimm_provider_data(dimm);
1133
1134         return sprintf(buf, "%#llx\n",
1135                        READ_ONCE(p->health_bitmap_inject_mask));
1136 }
1137
1138 static DEVICE_ATTR_ADMIN_RO(health_bitmap_inject);
1139
1140 static ssize_t perf_stats_show(struct device *dev,
1141                                struct device_attribute *attr, char *buf)
1142 {
1143         int index;
1144         ssize_t rc;
1145         struct seq_buf s;
1146         struct papr_scm_perf_stat *stat;
1147         struct papr_scm_perf_stats *stats;
1148         struct nvdimm *dimm = to_nvdimm(dev);
1149         struct papr_scm_priv *p = nvdimm_provider_data(dimm);
1150
1151         if (!p->stat_buffer_len)
1152                 return -ENOENT;
1153
1154         /* Allocate the buffer for phyp where stats are written */
1155         stats = kzalloc(p->stat_buffer_len, GFP_KERNEL);
1156         if (!stats)
1157                 return -ENOMEM;
1158
1159         /* Ask phyp to return all dimm perf stats */
1160         rc = drc_pmem_query_stats(p, stats, 0);
1161         if (rc)
1162                 goto free_stats;
1163         /*
1164          * Go through the returned output buffer and print stats and
1165          * values. Since stat_id is essentially a char string of
1166          * 8 bytes, simply use the string format specifier to print it.
1167          */
1168         seq_buf_init(&s, buf, PAGE_SIZE);
1169         for (index = 0, stat = stats->scm_statistic;
1170              index < be32_to_cpu(stats->num_statistics);
1171              ++index, ++stat) {
1172                 seq_buf_printf(&s, "%.8s = 0x%016llX\n",
1173                                stat->stat_id,
1174                                be64_to_cpu(stat->stat_val));
1175         }
1176
1177 free_stats:
1178         kfree(stats);
1179         return rc ? rc : (ssize_t)seq_buf_used(&s);
1180 }
1181 static DEVICE_ATTR_ADMIN_RO(perf_stats);
1182
1183 static ssize_t flags_show(struct device *dev,
1184                           struct device_attribute *attr, char *buf)
1185 {
1186         struct nvdimm *dimm = to_nvdimm(dev);
1187         struct papr_scm_priv *p = nvdimm_provider_data(dimm);
1188         struct seq_buf s;
1189         u64 health;
1190         int rc;
1191
1192         rc = drc_pmem_query_health(p);
1193         if (rc)
1194                 return rc;
1195
1196         /* Copy health_bitmap locally, check masks & update out buffer */
1197         health = READ_ONCE(p->health_bitmap);
1198
1199         seq_buf_init(&s, buf, PAGE_SIZE);
1200         if (health & PAPR_PMEM_UNARMED_MASK)
1201                 seq_buf_printf(&s, "not_armed ");
1202
1203         if (health & PAPR_PMEM_BAD_SHUTDOWN_MASK)
1204                 seq_buf_printf(&s, "flush_fail ");
1205
1206         if (health & PAPR_PMEM_BAD_RESTORE_MASK)
1207                 seq_buf_printf(&s, "restore_fail ");
1208
1209         if (health & PAPR_PMEM_ENCRYPTED)
1210                 seq_buf_printf(&s, "encrypted ");
1211
1212         if (health & PAPR_PMEM_SMART_EVENT_MASK)
1213                 seq_buf_printf(&s, "smart_notify ");
1214
1215         if (health & PAPR_PMEM_SCRUBBED_AND_LOCKED)
1216                 seq_buf_printf(&s, "scrubbed locked ");
1217
1218         if (seq_buf_used(&s))
1219                 seq_buf_printf(&s, "\n");
1220
1221         return seq_buf_used(&s);
1222 }
1223 DEVICE_ATTR_RO(flags);
1224
1225 static ssize_t dirty_shutdown_show(struct device *dev,
1226                           struct device_attribute *attr, char *buf)
1227 {
1228         struct nvdimm *dimm = to_nvdimm(dev);
1229         struct papr_scm_priv *p = nvdimm_provider_data(dimm);
1230
1231         return sysfs_emit(buf, "%llu\n", p->dirty_shutdown_counter);
1232 }
1233 DEVICE_ATTR_RO(dirty_shutdown);
1234
1235 static umode_t papr_nd_attribute_visible(struct kobject *kobj,
1236                                          struct attribute *attr, int n)
1237 {
1238         struct device *dev = kobj_to_dev(kobj);
1239         struct nvdimm *nvdimm = to_nvdimm(dev);
1240         struct papr_scm_priv *p = nvdimm_provider_data(nvdimm);
1241
1242         /* For if perf-stats not available remove perf_stats sysfs */
1243         if (attr == &dev_attr_perf_stats.attr && p->stat_buffer_len == 0)
1244                 return 0;
1245
1246         return attr->mode;
1247 }
1248
1249 /* papr_scm specific dimm attributes */
1250 static struct attribute *papr_nd_attributes[] = {
1251         &dev_attr_flags.attr,
1252         &dev_attr_perf_stats.attr,
1253         &dev_attr_dirty_shutdown.attr,
1254         &dev_attr_health_bitmap_inject.attr,
1255         NULL,
1256 };
1257
1258 static const struct attribute_group papr_nd_attribute_group = {
1259         .name = "papr",
1260         .is_visible = papr_nd_attribute_visible,
1261         .attrs = papr_nd_attributes,
1262 };
1263
1264 static const struct attribute_group *papr_nd_attr_groups[] = {
1265         &papr_nd_attribute_group,
1266         NULL,
1267 };
1268
1269 static int papr_scm_nvdimm_init(struct papr_scm_priv *p)
1270 {
1271         struct device *dev = &p->pdev->dev;
1272         struct nd_mapping_desc mapping;
1273         struct nd_region_desc ndr_desc;
1274         unsigned long dimm_flags;
1275         int target_nid, online_nid;
1276
1277         p->bus_desc.ndctl = papr_scm_ndctl;
1278         p->bus_desc.module = THIS_MODULE;
1279         p->bus_desc.of_node = p->pdev->dev.of_node;
1280         p->bus_desc.provider_name = kstrdup(p->pdev->name, GFP_KERNEL);
1281
1282         /* Set the dimm command family mask to accept PDSMs */
1283         set_bit(NVDIMM_FAMILY_PAPR, &p->bus_desc.dimm_family_mask);
1284
1285         if (!p->bus_desc.provider_name)
1286                 return -ENOMEM;
1287
1288         p->bus = nvdimm_bus_register(NULL, &p->bus_desc);
1289         if (!p->bus) {
1290                 dev_err(dev, "Error creating nvdimm bus %pOF\n", p->dn);
1291                 kfree(p->bus_desc.provider_name);
1292                 return -ENXIO;
1293         }
1294
1295         dimm_flags = 0;
1296         set_bit(NDD_LABELING, &dimm_flags);
1297
1298         /*
1299          * Check if the nvdimm is unarmed. No locking needed as we are still
1300          * initializing. Ignore error encountered if any.
1301          */
1302         __drc_pmem_query_health(p);
1303
1304         if (p->health_bitmap & PAPR_PMEM_UNARMED_MASK)
1305                 set_bit(NDD_UNARMED, &dimm_flags);
1306
1307         p->nvdimm = nvdimm_create(p->bus, p, papr_nd_attr_groups,
1308                                   dimm_flags, PAPR_SCM_DIMM_CMD_MASK, 0, NULL);
1309         if (!p->nvdimm) {
1310                 dev_err(dev, "Error creating DIMM object for %pOF\n", p->dn);
1311                 goto err;
1312         }
1313
1314         if (nvdimm_bus_check_dimm_count(p->bus, 1))
1315                 goto err;
1316
1317         /* now add the region */
1318
1319         memset(&mapping, 0, sizeof(mapping));
1320         mapping.nvdimm = p->nvdimm;
1321         mapping.start = 0;
1322         mapping.size = p->blocks * p->block_size; // XXX: potential overflow?
1323
1324         memset(&ndr_desc, 0, sizeof(ndr_desc));
1325         target_nid = dev_to_node(&p->pdev->dev);
1326         online_nid = numa_map_to_online_node(target_nid);
1327         ndr_desc.numa_node = online_nid;
1328         ndr_desc.target_node = target_nid;
1329         ndr_desc.res = &p->res;
1330         ndr_desc.of_node = p->dn;
1331         ndr_desc.provider_data = p;
1332         ndr_desc.mapping = &mapping;
1333         ndr_desc.num_mappings = 1;
1334         ndr_desc.nd_set = &p->nd_set;
1335
1336         if (p->hcall_flush_required) {
1337                 set_bit(ND_REGION_ASYNC, &ndr_desc.flags);
1338                 ndr_desc.flush = papr_scm_pmem_flush;
1339         }
1340
1341         if (p->is_volatile)
1342                 p->region = nvdimm_volatile_region_create(p->bus, &ndr_desc);
1343         else {
1344                 set_bit(ND_REGION_PERSIST_MEMCTRL, &ndr_desc.flags);
1345                 p->region = nvdimm_pmem_region_create(p->bus, &ndr_desc);
1346         }
1347         if (!p->region) {
1348                 dev_err(dev, "Error registering region %pR from %pOF\n",
1349                                 ndr_desc.res, p->dn);
1350                 goto err;
1351         }
1352         if (target_nid != online_nid)
1353                 dev_info(dev, "Region registered with target node %d and online node %d",
1354                          target_nid, online_nid);
1355
1356         mutex_lock(&papr_ndr_lock);
1357         list_add_tail(&p->region_list, &papr_nd_regions);
1358         mutex_unlock(&papr_ndr_lock);
1359
1360         return 0;
1361
1362 err:    nvdimm_bus_unregister(p->bus);
1363         kfree(p->bus_desc.provider_name);
1364         return -ENXIO;
1365 }
1366
1367 static void papr_scm_add_badblock(struct nd_region *region,
1368                                   struct nvdimm_bus *bus, u64 phys_addr)
1369 {
1370         u64 aligned_addr = ALIGN_DOWN(phys_addr, L1_CACHE_BYTES);
1371
1372         if (nvdimm_bus_add_badrange(bus, aligned_addr, L1_CACHE_BYTES)) {
1373                 pr_err("Bad block registration for 0x%llx failed\n", phys_addr);
1374                 return;
1375         }
1376
1377         pr_debug("Add memory range (0x%llx - 0x%llx) as bad range\n",
1378                  aligned_addr, aligned_addr + L1_CACHE_BYTES);
1379
1380         nvdimm_region_notify(region, NVDIMM_REVALIDATE_POISON);
1381 }
1382
1383 static int handle_mce_ue(struct notifier_block *nb, unsigned long val,
1384                          void *data)
1385 {
1386         struct machine_check_event *evt = data;
1387         struct papr_scm_priv *p;
1388         u64 phys_addr;
1389         bool found = false;
1390
1391         if (evt->error_type != MCE_ERROR_TYPE_UE)
1392                 return NOTIFY_DONE;
1393
1394         if (list_empty(&papr_nd_regions))
1395                 return NOTIFY_DONE;
1396
1397         /*
1398          * The physical address obtained here is PAGE_SIZE aligned, so get the
1399          * exact address from the effective address
1400          */
1401         phys_addr = evt->u.ue_error.physical_address +
1402                         (evt->u.ue_error.effective_address & ~PAGE_MASK);
1403
1404         if (!evt->u.ue_error.physical_address_provided ||
1405             !is_zone_device_page(pfn_to_page(phys_addr >> PAGE_SHIFT)))
1406                 return NOTIFY_DONE;
1407
1408         /* mce notifier is called from a process context, so mutex is safe */
1409         mutex_lock(&papr_ndr_lock);
1410         list_for_each_entry(p, &papr_nd_regions, region_list) {
1411                 if (phys_addr >= p->res.start && phys_addr <= p->res.end) {
1412                         found = true;
1413                         break;
1414                 }
1415         }
1416
1417         if (found)
1418                 papr_scm_add_badblock(p->region, p->bus, phys_addr);
1419
1420         mutex_unlock(&papr_ndr_lock);
1421
1422         return found ? NOTIFY_OK : NOTIFY_DONE;
1423 }
1424
1425 static struct notifier_block mce_ue_nb = {
1426         .notifier_call = handle_mce_ue
1427 };
1428
1429 static int papr_scm_probe(struct platform_device *pdev)
1430 {
1431         struct device_node *dn = pdev->dev.of_node;
1432         u32 drc_index, metadata_size;
1433         u64 blocks, block_size;
1434         struct papr_scm_priv *p;
1435         u8 uuid_raw[UUID_SIZE];
1436         const char *uuid_str;
1437         ssize_t stat_size;
1438         uuid_t uuid;
1439         int rc;
1440
1441         /* check we have all the required DT properties */
1442         if (of_property_read_u32(dn, "ibm,my-drc-index", &drc_index)) {
1443                 dev_err(&pdev->dev, "%pOF: missing drc-index!\n", dn);
1444                 return -ENODEV;
1445         }
1446
1447         if (of_property_read_u64(dn, "ibm,block-size", &block_size)) {
1448                 dev_err(&pdev->dev, "%pOF: missing block-size!\n", dn);
1449                 return -ENODEV;
1450         }
1451
1452         if (of_property_read_u64(dn, "ibm,number-of-blocks", &blocks)) {
1453                 dev_err(&pdev->dev, "%pOF: missing number-of-blocks!\n", dn);
1454                 return -ENODEV;
1455         }
1456
1457         if (of_property_read_string(dn, "ibm,unit-guid", &uuid_str)) {
1458                 dev_err(&pdev->dev, "%pOF: missing unit-guid!\n", dn);
1459                 return -ENODEV;
1460         }
1461
1462
1463         p = kzalloc(sizeof(*p), GFP_KERNEL);
1464         if (!p)
1465                 return -ENOMEM;
1466
1467         /* Initialize the dimm mutex */
1468         mutex_init(&p->health_mutex);
1469
1470         /* optional DT properties */
1471         of_property_read_u32(dn, "ibm,metadata-size", &metadata_size);
1472
1473         p->dn = dn;
1474         p->drc_index = drc_index;
1475         p->block_size = block_size;
1476         p->blocks = blocks;
1477         p->is_volatile = !of_property_read_bool(dn, "ibm,cache-flush-required");
1478         p->hcall_flush_required = of_property_read_bool(dn, "ibm,hcall-flush-required");
1479
1480         if (of_property_read_u64(dn, "ibm,persistence-failed-count",
1481                                  &p->dirty_shutdown_counter))
1482                 p->dirty_shutdown_counter = 0;
1483
1484         /* We just need to ensure that set cookies are unique across */
1485         uuid_parse(uuid_str, &uuid);
1486
1487         /*
1488          * The cookie1 and cookie2 are not really little endian.
1489          * We store a raw buffer representation of the
1490          * uuid string so that we can compare this with the label
1491          * area cookie irrespective of the endian configuration
1492          * with which the kernel is built.
1493          *
1494          * Historically we stored the cookie in the below format.
1495          * for a uuid string 72511b67-0b3b-42fd-8d1d-5be3cae8bcaa
1496          *      cookie1 was 0xfd423b0b671b5172
1497          *      cookie2 was 0xaabce8cae35b1d8d
1498          */
1499         export_uuid(uuid_raw, &uuid);
1500         p->nd_set.cookie1 = get_unaligned_le64(&uuid_raw[0]);
1501         p->nd_set.cookie2 = get_unaligned_le64(&uuid_raw[8]);
1502
1503         /* might be zero */
1504         p->metadata_size = metadata_size;
1505         p->pdev = pdev;
1506
1507         /* request the hypervisor to bind this region to somewhere in memory */
1508         rc = drc_pmem_bind(p);
1509
1510         /* If phyp says drc memory still bound then force unbound and retry */
1511         if (rc == H_OVERLAP)
1512                 rc = drc_pmem_query_n_bind(p);
1513
1514         if (rc != H_SUCCESS) {
1515                 dev_err(&p->pdev->dev, "bind err: %d\n", rc);
1516                 rc = -ENXIO;
1517                 goto err;
1518         }
1519
1520         /* setup the resource for the newly bound range */
1521         p->res.start = p->bound_addr;
1522         p->res.end   = p->bound_addr + p->blocks * p->block_size - 1;
1523         p->res.name  = pdev->name;
1524         p->res.flags = IORESOURCE_MEM;
1525
1526         /* Try retrieving the stat buffer and see if its supported */
1527         stat_size = drc_pmem_query_stats(p, NULL, 0);
1528         if (stat_size > 0) {
1529                 p->stat_buffer_len = stat_size;
1530                 dev_dbg(&p->pdev->dev, "Max perf-stat size %lu-bytes\n",
1531                         p->stat_buffer_len);
1532         }
1533
1534         rc = papr_scm_nvdimm_init(p);
1535         if (rc)
1536                 goto err2;
1537
1538         platform_set_drvdata(pdev, p);
1539         papr_scm_pmu_register(p);
1540
1541         return 0;
1542
1543 err2:   drc_pmem_unbind(p);
1544 err:    kfree(p);
1545         return rc;
1546 }
1547
1548 static int papr_scm_remove(struct platform_device *pdev)
1549 {
1550         struct papr_scm_priv *p = platform_get_drvdata(pdev);
1551
1552         mutex_lock(&papr_ndr_lock);
1553         list_del(&p->region_list);
1554         mutex_unlock(&papr_ndr_lock);
1555
1556         nvdimm_bus_unregister(p->bus);
1557         drc_pmem_unbind(p);
1558
1559         if (pdev->archdata.priv)
1560                 unregister_nvdimm_pmu(pdev->archdata.priv);
1561
1562         pdev->archdata.priv = NULL;
1563         kfree(p->nvdimm_events_map);
1564         kfree(p->bus_desc.provider_name);
1565         kfree(p);
1566
1567         return 0;
1568 }
1569
1570 static const struct of_device_id papr_scm_match[] = {
1571         { .compatible = "ibm,pmemory" },
1572         { .compatible = "ibm,pmemory-v2" },
1573         { },
1574 };
1575
1576 static struct platform_driver papr_scm_driver = {
1577         .probe = papr_scm_probe,
1578         .remove = papr_scm_remove,
1579         .driver = {
1580                 .name = "papr_scm",
1581                 .of_match_table = papr_scm_match,
1582         },
1583 };
1584
1585 static int __init papr_scm_init(void)
1586 {
1587         int ret;
1588
1589         ret = platform_driver_register(&papr_scm_driver);
1590         if (!ret)
1591                 mce_register_notifier(&mce_ue_nb);
1592
1593         return ret;
1594 }
1595 module_init(papr_scm_init);
1596
1597 static void __exit papr_scm_exit(void)
1598 {
1599         mce_unregister_notifier(&mce_ue_nb);
1600         platform_driver_unregister(&papr_scm_driver);
1601 }
1602 module_exit(papr_scm_exit);
1603
1604 MODULE_DEVICE_TABLE(of, papr_scm_match);
1605 MODULE_LICENSE("GPL");
1606 MODULE_AUTHOR("IBM Corporation");