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 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
 129 static int papr_scm_pmem_flush(struct nd_region *nd_region,
 130                                struct bio *bio __maybe_unused)
 131 {
 132         struct papr_scm_priv *p = nd_region_provider_data(nd_region);
 133         unsigned long ret_buf[PLPAR_HCALL_BUFSIZE], token = 0;
 134         long rc;
 135
 136         dev_dbg(&p->pdev->dev, "flush drc 0x%x", p->drc_index);
 137
 138         do {
 139                 rc = plpar_hcall(H_SCM_FLUSH, ret_buf, p->drc_index, token);
 140                 token = ret_buf[0];
 141
 142                 /* Check if we are stalled for some time */
 143                 if (H_IS_LONG_BUSY(rc)) {
 144                         msleep(get_longbusy_msecs(rc));
 145                         rc = H_BUSY;
 146                 } else if (rc == H_BUSY) {
 147                         cond_resched();
 148                 }
 149         } while (rc == H_BUSY);
 150
 151         if (rc) {
 152                 dev_err(&p->pdev->dev, "flush error: %ld", rc);
 153                 rc = -EIO;
 154         } else {
 155                 dev_dbg(&p->pdev->dev, "flush drc 0x%x complete", p->drc_index);
 156         }
 157
 158         return rc;
 159 }
 160
 161 static LIST_HEAD(papr_nd_regions);
 162 static DEFINE_MUTEX(papr_ndr_lock);
 163
 164 static int drc_pmem_bind(struct papr_scm_priv *p)
 165 {
 166         unsigned long ret[PLPAR_HCALL_BUFSIZE];
 167         uint64_t saved = 0;
 168         uint64_t token;
 169         int64_t rc;
 170
 171         /*
 172          * When the hypervisor cannot map all the requested memory in a single
 173          * hcall it returns H_BUSY and we call again with the token until
 174          * we get H_SUCCESS. Aborting the retry loop before getting H_SUCCESS
 175          * leave the system in an undefined state, so we wait.
 176          */
 177         token = 0;
 178
 179         do {
 180                 rc = plpar_hcall(H_SCM_BIND_MEM, ret, p->drc_index, 0,
 181                                 p->blocks, BIND_ANY_ADDR, token);
 182                 token = ret[0];
 183                 if (!saved)
 184                         saved = ret[1];
 185                 cond_resched();
 186         } while (rc == H_BUSY);
 187
 188         if (rc)
 189                 return rc;
 190
 191         p->bound_addr = saved;
 192         dev_dbg(&p->pdev->dev, "bound drc 0x%x to 0x%lx\n",
 193                 p->drc_index, (unsigned long)saved);
 194         return rc;
 195 }
 196
 197 static void drc_pmem_unbind(struct papr_scm_priv *p)
 198 {
 199         unsigned long ret[PLPAR_HCALL_BUFSIZE];
 200         uint64_t token = 0;
 201         int64_t rc;
 202
 203         dev_dbg(&p->pdev->dev, "unbind drc 0x%x\n", p->drc_index);
 204
 205         /* NB: unbind has the same retry requirements as drc_pmem_bind() */
 206         do {
 207
 208                 /* Unbind of all SCM resources associated with drcIndex */
 209                 rc = plpar_hcall(H_SCM_UNBIND_ALL, ret, H_UNBIND_SCOPE_DRC,
 210                                  p->drc_index, token);
 211                 token = ret[0];
 212
 213                 /* Check if we are stalled for some time */
 214                 if (H_IS_LONG_BUSY(rc)) {
 215                         msleep(get_longbusy_msecs(rc));
 216                         rc = H_BUSY;
 217                 } else if (rc == H_BUSY) {
 218                         cond_resched();
 219                 }
 220
 221         } while (rc == H_BUSY);
 222
 223         if (rc)
 224                 dev_err(&p->pdev->dev, "unbind error: %lld\n", rc);
 225         else
 226                 dev_dbg(&p->pdev->dev, "unbind drc 0x%x complete\n",
 227                         p->drc_index);
 228
 229         return;
 230 }
 231
 232 static int drc_pmem_query_n_bind(struct papr_scm_priv *p)
 233 {
 234         unsigned long start_addr;
 235         unsigned long end_addr;
 236         unsigned long ret[PLPAR_HCALL_BUFSIZE];
 237         int64_t rc;
 238
 239
 240         rc = plpar_hcall(H_SCM_QUERY_BLOCK_MEM_BINDING, ret,
 241                          p->drc_index, 0);
 242         if (rc)
 243                 goto err_out;
 244         start_addr = ret[0];
 245
 246         /* Make sure the full region is bound. */
 247         rc = plpar_hcall(H_SCM_QUERY_BLOCK_MEM_BINDING, ret,
 248                          p->drc_index, p->blocks - 1);
 249         if (rc)
 250                 goto err_out;
 251         end_addr = ret[0];
 252
 253         if ((end_addr - start_addr) != ((p->blocks - 1) * p->block_size))
 254                 goto err_out;
 255
 256         p->bound_addr = start_addr;
 257         dev_dbg(&p->pdev->dev, "bound drc 0x%x to 0x%lx\n", p->drc_index, start_addr);
 258         return rc;
 259
 260 err_out:
 261         dev_info(&p->pdev->dev,
 262                  "Failed to query, trying an unbind followed by bind");
 263         drc_pmem_unbind(p);
 264         return drc_pmem_bind(p);
 265 }
 266
 267 /*
 268  * Query the Dimm performance stats from PHYP and copy them (if returned) to
 269  * provided struct papr_scm_perf_stats instance 'stats' that can hold atleast
 270  * (num_stats + header) bytes.
 271  * - If buff_stats == NULL the return value is the size in bytes of the buffer
 272  * needed to hold all supported performance-statistics.
 273  * - If buff_stats != NULL and num_stats == 0 then we copy all known
 274  * performance-statistics to 'buff_stat' and expect to be large enough to
 275  * hold them.
 276  * - if buff_stats != NULL and num_stats > 0 then copy the requested
 277  * performance-statistics to buff_stats.
 278  */
 279 static ssize_t drc_pmem_query_stats(struct papr_scm_priv *p,
 280                                     struct papr_scm_perf_stats *buff_stats,
 281                                     unsigned int num_stats)
 282 {
 283         unsigned long ret[PLPAR_HCALL_BUFSIZE];
 284         size_t size;
 285         s64 rc;
 286
 287         /* Setup the out buffer */
 288         if (buff_stats) {
 289                 memcpy(buff_stats->eye_catcher,
 290                        PAPR_SCM_PERF_STATS_EYECATCHER, 8);
 291                 buff_stats->stats_version =
 292                         cpu_to_be32(PAPR_SCM_PERF_STATS_VERSION);
 293                 buff_stats->num_statistics =
 294                         cpu_to_be32(num_stats);
 295
 296                 /*
 297                  * Calculate the buffer size based on num-stats provided
 298                  * or use the prefetched max buffer length
 299                  */
 300                 if (num_stats)
 301                         /* Calculate size from the num_stats */
 302                         size = sizeof(struct papr_scm_perf_stats) +
 303                                 num_stats * sizeof(struct papr_scm_perf_stat);
 304                 else
 305                         size = p->stat_buffer_len;
 306         } else {
 307                 /* In case of no out buffer ignore the size */
 308                 size = 0;
 309         }
 310
 311         /* Do the HCALL asking PHYP for info */
 312         rc = plpar_hcall(H_SCM_PERFORMANCE_STATS, ret, p->drc_index,
 313                          buff_stats ? virt_to_phys(buff_stats) : 0,
 314                          size);
 315
 316         /* Check if the error was due to an unknown stat-id */
 317         if (rc == H_PARTIAL) {
 318                 dev_err(&p->pdev->dev,
 319                         "Unknown performance stats, Err:0x%016lX\n", ret[0]);
 320                 return -ENOENT;
 321         } else if (rc == H_AUTHORITY) {
 322                 dev_info(&p->pdev->dev,
 323                          "Permission denied while accessing performance stats");
 324                 return -EPERM;
 325         } else if (rc == H_UNSUPPORTED) {
 326                 dev_dbg(&p->pdev->dev, "Performance stats unsupported\n");
 327                 return -EOPNOTSUPP;
 328         } else if (rc != H_SUCCESS) {
 329                 dev_err(&p->pdev->dev,
 330                         "Failed to query performance stats, Err:%lld\n", rc);
 331                 return -EIO;
 332
 333         } else if (!size) {
 334                 /* Handle case where stat buffer size was requested */
 335                 dev_dbg(&p->pdev->dev,
 336                         "Performance stats size %ld\n", ret[0]);
 337                 return ret[0];
 338         }
 339
 340         /* Successfully fetched the requested stats from phyp */
 341         dev_dbg(&p->pdev->dev,
 342                 "Performance stats returned %d stats\n",
 343                 be32_to_cpu(buff_stats->num_statistics));
 344         return 0;
 345 }
 346
 347 #ifdef CONFIG_PERF_EVENTS
 348 #define to_nvdimm_pmu(_pmu)     container_of(_pmu, struct nvdimm_pmu, pmu)
 349
 350 static const char * const nvdimm_events_map[] = {
 351         [1] = "CtlResCt",
 352         [2] = "CtlResTm",
 353         [3] = "PonSecs ",
 354         [4] = "MemLife ",
 355         [5] = "CritRscU",
 356         [6] = "HostLCnt",
 357         [7] = "HostSCnt",
 358         [8] = "HostSDur",
 359         [9] = "HostLDur",
 360         [10] = "MedRCnt ",
 361         [11] = "MedWCnt ",
 362         [12] = "MedRDur ",
 363         [13] = "MedWDur ",
 364         [14] = "CchRHCnt",
 365         [15] = "CchWHCnt",
 366         [16] = "FastWCnt",
 367 };
 368
 369 static int papr_scm_pmu_get_value(struct perf_event *event, struct device *dev, u64 *count)
 370 {
 371         struct papr_scm_perf_stat *stat;
 372         struct papr_scm_perf_stats *stats;
 373         struct papr_scm_priv *p = dev_get_drvdata(dev);
 374         int rc, size;
 375
 376         /* Invalid eventcode */
 377         if (event->attr.config == 0 || event->attr.config >= ARRAY_SIZE(nvdimm_events_map))
 378                 return -EINVAL;
 379
 380         /* Allocate request buffer enough to hold single performance stat */
 381         size = sizeof(struct papr_scm_perf_stats) +
 382                 sizeof(struct papr_scm_perf_stat);
 383
 384         if (!p)
 385                 return -EINVAL;
 386
 387         stats = kzalloc(size, GFP_KERNEL);
 388         if (!stats)
 389                 return -ENOMEM;
 390
 391         stat = &stats->scm_statistic[0];
 392         memcpy(&stat->stat_id,
 393                nvdimm_events_map[event->attr.config],
 394                 sizeof(stat->stat_id));
 395         stat->stat_val = 0;
 396
 397         rc = drc_pmem_query_stats(p, stats, 1);
 398         if (rc < 0) {
 399                 kfree(stats);
 400                 return rc;
 401         }
 402
 403         *count = be64_to_cpu(stat->stat_val);
 404         kfree(stats);
 405         return 0;
 406 }
 407
 408 static int papr_scm_pmu_event_init(struct perf_event *event)
 409 {
 410         struct nvdimm_pmu *nd_pmu = to_nvdimm_pmu(event->pmu);
 411         struct papr_scm_priv *p;
 412
 413         if (!nd_pmu)
 414                 return -EINVAL;
 415
 416         /* test the event attr type for PMU enumeration */
 417         if (event->attr.type != event->pmu->type)
 418                 return -ENOENT;
 419
 420         /* it does not support event sampling mode */
 421         if (is_sampling_event(event))
 422                 return -EOPNOTSUPP;
 423
 424         /* no branch sampling */
 425         if (has_branch_stack(event))
 426                 return -EOPNOTSUPP;
 427
 428         p = (struct papr_scm_priv *)nd_pmu->dev->driver_data;
 429         if (!p)
 430                 return -EINVAL;
 431
 432         /* Invalid eventcode */
 433         if (event->attr.config == 0 || event->attr.config > 16)
 434                 return -EINVAL;
 435
 436         return 0;
 437 }
 438
 439 static int papr_scm_pmu_add(struct perf_event *event, int flags)
 440 {
 441         u64 count;
 442         int rc;
 443         struct nvdimm_pmu *nd_pmu = to_nvdimm_pmu(event->pmu);
 444
 445         if (!nd_pmu)
 446                 return -EINVAL;
 447
 448         if (flags & PERF_EF_START) {
 449                 rc = papr_scm_pmu_get_value(event, nd_pmu->dev, &count);
 450                 if (rc)
 451                         return rc;
 452
 453                 local64_set(&event->hw.prev_count, count);
 454         }
 455
 456         return 0;
 457 }
 458
 459 static void papr_scm_pmu_read(struct perf_event *event)
 460 {
 461         u64 prev, now;
 462         int rc;
 463         struct nvdimm_pmu *nd_pmu = to_nvdimm_pmu(event->pmu);
 464
 465         if (!nd_pmu)
 466                 return;
 467
 468         rc = papr_scm_pmu_get_value(event, nd_pmu->dev, &now);
 469         if (rc)
 470                 return;
 471
 472         prev = local64_xchg(&event->hw.prev_count, now);
 473         local64_add(now - prev, &event->count);
 474 }
 475
 476 static void papr_scm_pmu_del(struct perf_event *event, int flags)
 477 {
 478         papr_scm_pmu_read(event);
 479 }
 480
 481 static void papr_scm_pmu_register(struct papr_scm_priv *p)
 482 {
 483         struct nvdimm_pmu *nd_pmu;
 484         int rc, nodeid;
 485
 486         nd_pmu = kzalloc(sizeof(*nd_pmu), GFP_KERNEL);
 487         if (!nd_pmu) {
 488                 rc = -ENOMEM;
 489                 goto pmu_err_print;
 490         }
 491
 492         if (!p->stat_buffer_len) {
 493                 rc = -ENOENT;
 494                 goto pmu_check_events_err;
 495         }
 496
 497         nd_pmu->pmu.task_ctx_nr = perf_invalid_context;
 498         nd_pmu->pmu.name = nvdimm_name(p->nvdimm);
 499         nd_pmu->pmu.event_init = papr_scm_pmu_event_init;
 500         nd_pmu->pmu.read = papr_scm_pmu_read;
 501         nd_pmu->pmu.add = papr_scm_pmu_add;
 502         nd_pmu->pmu.del = papr_scm_pmu_del;
 503
 504         nd_pmu->pmu.capabilities = PERF_PMU_CAP_NO_INTERRUPT |
 505                                 PERF_PMU_CAP_NO_EXCLUDE;
 506
 507         /*updating the cpumask variable */
 508         nodeid = numa_map_to_online_node(dev_to_node(&p->pdev->dev));
 509         nd_pmu->arch_cpumask = *cpumask_of_node(nodeid);
 510
 511         rc = register_nvdimm_pmu(nd_pmu, p->pdev);
 512         if (rc)
 513                 goto pmu_check_events_err;
 514
 515         /*
 516          * Set archdata.priv value to nvdimm_pmu structure, to handle the
 517          * unregistering of pmu device.
 518          */
 519         p->pdev->archdata.priv = nd_pmu;
 520         return;
 521
 522 pmu_check_events_err:
 523         kfree(nd_pmu);
 524 pmu_err_print:
 525         dev_info(&p->pdev->dev, "nvdimm pmu didn't register rc=%d\n", rc);
 526 }
 527
 528 #else
 529 static void papr_scm_pmu_register(struct papr_scm_priv *p) { }
 530 #endif
 531
 532 /*
 533  * Issue hcall to retrieve dimm health info and populate papr_scm_priv with the
 534  * health information.
 535  */
 536 static int __drc_pmem_query_health(struct papr_scm_priv *p)
 537 {
 538         unsigned long ret[PLPAR_HCALL_BUFSIZE];
 539         u64 bitmap = 0;
 540         long rc;
 541
 542         /* issue the hcall */
 543         rc = plpar_hcall(H_SCM_HEALTH, ret, p->drc_index);
 544         if (rc == H_SUCCESS)
 545                 bitmap = ret[0] & ret[1];
 546         else if (rc == H_FUNCTION)
 547                 dev_info_once(&p->pdev->dev,
 548                               "Hcall H_SCM_HEALTH not implemented, assuming empty health bitmap");
 549         else {
 550
 551                 dev_err(&p->pdev->dev,
 552                         "Failed to query health information, Err:%ld\n", rc);
 553                 return -ENXIO;
 554         }
 555
 556         p->lasthealth_jiffies = jiffies;
 557         /* Allow injecting specific health bits via inject mask. */
 558         if (p->health_bitmap_inject_mask)
 559                 bitmap = (bitmap & ~p->health_bitmap_inject_mask) |
 560                         p->health_bitmap_inject_mask;
 561         WRITE_ONCE(p->health_bitmap, bitmap);
 562         dev_dbg(&p->pdev->dev,
 563                 "Queried dimm health info. Bitmap:0x%016lx Mask:0x%016lx\n",
 564                 ret[0], ret[1]);
 565
 566         return 0;
 567 }
 568
 569 /* Min interval in seconds for assuming stable dimm health */
 570 #define MIN_HEALTH_QUERY_INTERVAL 60
 571
 572 /* Query cached health info and if needed call drc_pmem_query_health */
 573 static int drc_pmem_query_health(struct papr_scm_priv *p)
 574 {
 575         unsigned long cache_timeout;
 576         int rc;
 577
 578         /* Protect concurrent modifications to papr_scm_priv */
 579         rc = mutex_lock_interruptible(&p->health_mutex);
 580         if (rc)
 581                 return rc;
 582
 583         /* Jiffies offset for which the health data is assumed to be same */
 584         cache_timeout = p->lasthealth_jiffies +
 585                 msecs_to_jiffies(MIN_HEALTH_QUERY_INTERVAL * 1000);
 586
 587         /* Fetch new health info is its older than MIN_HEALTH_QUERY_INTERVAL */
 588         if (time_after(jiffies, cache_timeout))
 589                 rc = __drc_pmem_query_health(p);
 590         else
 591                 /* Assume cached health data is valid */
 592                 rc = 0;
 593
 594         mutex_unlock(&p->health_mutex);
 595         return rc;
 596 }
 597
 598 static int papr_scm_meta_get(struct papr_scm_priv *p,
 599                              struct nd_cmd_get_config_data_hdr *hdr)
 600 {
 601         unsigned long data[PLPAR_HCALL_BUFSIZE];
 602         unsigned long offset, data_offset;
 603         int len, read;
 604         int64_t ret;
 605
 606         if ((hdr->in_offset + hdr->in_length) > p->metadata_size)
 607                 return -EINVAL;
 608
 609         for (len = hdr->in_length; len; len -= read) {
 610
 611                 data_offset = hdr->in_length - len;
 612                 offset = hdr->in_offset + data_offset;
 613
 614                 if (len >= 8)
 615                         read = 8;
 616                 else if (len >= 4)
 617                         read = 4;
 618                 else if (len >= 2)
 619                         read = 2;
 620                 else
 621                         read = 1;
 622
 623                 ret = plpar_hcall(H_SCM_READ_METADATA, data, p->drc_index,
 624                                   offset, read);
 625
 626                 if (ret == H_PARAMETER) /* bad DRC index */
 627                         return -ENODEV;
 628                 if (ret)
 629                         return -EINVAL; /* other invalid parameter */
 630
 631                 switch (read) {
 632                 case 8:
 633                         *(uint64_t *)(hdr->out_buf + data_offset) = be64_to_cpu(data[0]);
 634                         break;
 635                 case 4:
 636                         *(uint32_t *)(hdr->out_buf + data_offset) = be32_to_cpu(data[0] & 0xffffffff);
 637                         break;
 638
 639                 case 2:
 640                         *(uint16_t *)(hdr->out_buf + data_offset) = be16_to_cpu(data[0] & 0xffff);
 641                         break;
 642
 643                 case 1:
 644                         *(uint8_t *)(hdr->out_buf + data_offset) = (data[0] & 0xff);
 645                         break;
 646                 }
 647         }
 648         return 0;
 649 }
 650
 651 static int papr_scm_meta_set(struct papr_scm_priv *p,
 652                              struct nd_cmd_set_config_hdr *hdr)
 653 {
 654         unsigned long offset, data_offset;
 655         int len, wrote;
 656         unsigned long data;
 657         __be64 data_be;
 658         int64_t ret;
 659
 660         if ((hdr->in_offset + hdr->in_length) > p->metadata_size)
 661                 return -EINVAL;
 662
 663         for (len = hdr->in_length; len; len -= wrote) {
 664
 665                 data_offset = hdr->in_length - len;
 666                 offset = hdr->in_offset + data_offset;
 667
 668                 if (len >= 8) {
 669                         data = *(uint64_t *)(hdr->in_buf + data_offset);
 670                         data_be = cpu_to_be64(data);
 671                         wrote = 8;
 672                 } else if (len >= 4) {
 673                         data = *(uint32_t *)(hdr->in_buf + data_offset);
 674                         data &= 0xffffffff;
 675                         data_be = cpu_to_be32(data);
 676                         wrote = 4;
 677                 } else if (len >= 2) {
 678                         data = *(uint16_t *)(hdr->in_buf + data_offset);
 679                         data &= 0xffff;
 680                         data_be = cpu_to_be16(data);
 681                         wrote = 2;
 682                 } else {
 683                         data_be = *(uint8_t *)(hdr->in_buf + data_offset);
 684                         data_be &= 0xff;
 685                         wrote = 1;
 686                 }
 687
 688                 ret = plpar_hcall_norets(H_SCM_WRITE_METADATA, p->drc_index,
 689                                          offset, data_be, wrote);
 690                 if (ret == H_PARAMETER) /* bad DRC index */
 691                         return -ENODEV;
 692                 if (ret)
 693                         return -EINVAL; /* other invalid parameter */
 694         }
 695
 696         return 0;
 697 }
 698
 699 /*
 700  * Do a sanity checks on the inputs args to dimm-control function and return
 701  * '0' if valid. Validation of PDSM payloads happens later in
 702  * papr_scm_service_pdsm.
 703  */
 704 static int is_cmd_valid(struct nvdimm *nvdimm, unsigned int cmd, void *buf,
 705                         unsigned int buf_len)
 706 {
 707         unsigned long cmd_mask = PAPR_SCM_DIMM_CMD_MASK;
 708         struct nd_cmd_pkg *nd_cmd;
 709         struct papr_scm_priv *p;
 710         enum papr_pdsm pdsm;
 711
 712         /* Only dimm-specific calls are supported atm */
 713         if (!nvdimm)
 714                 return -EINVAL;
 715
 716         /* get the provider data from struct nvdimm */
 717         p = nvdimm_provider_data(nvdimm);
 718
 719         if (!test_bit(cmd, &cmd_mask)) {
 720                 dev_dbg(&p->pdev->dev, "Unsupported cmd=%u\n", cmd);
 721                 return -EINVAL;
 722         }
 723
 724         /* For CMD_CALL verify pdsm request */
 725         if (cmd == ND_CMD_CALL) {
 726                 /* Verify the envelope and envelop size */
 727                 if (!buf ||
 728                     buf_len < (sizeof(struct nd_cmd_pkg) + ND_PDSM_HDR_SIZE)) {
 729                         dev_dbg(&p->pdev->dev, "Invalid pkg size=%u\n",
 730                                 buf_len);
 731                         return -EINVAL;
 732                 }
 733
 734                 /* Verify that the nd_cmd_pkg.nd_family is correct */
 735                 nd_cmd = (struct nd_cmd_pkg *)buf;
 736
 737                 if (nd_cmd->nd_family != NVDIMM_FAMILY_PAPR) {
 738                         dev_dbg(&p->pdev->dev, "Invalid pkg family=0x%llx\n",
 739                                 nd_cmd->nd_family);
 740                         return -EINVAL;
 741                 }
 742
 743                 pdsm = (enum papr_pdsm)nd_cmd->nd_command;
 744
 745                 /* Verify if the pdsm command is valid */
 746                 if (pdsm <= PAPR_PDSM_MIN || pdsm >= PAPR_PDSM_MAX) {
 747                         dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Invalid PDSM\n",
 748                                 pdsm);
 749                         return -EINVAL;
 750                 }
 751
 752                 /* Have enough space to hold returned 'nd_pkg_pdsm' header */
 753                 if (nd_cmd->nd_size_out < ND_PDSM_HDR_SIZE) {
 754                         dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Invalid payload\n",
 755                                 pdsm);
 756                         return -EINVAL;
 757                 }
 758         }
 759
 760         /* Let the command be further processed */
 761         return 0;
 762 }
 763
 764 static int papr_pdsm_fuel_gauge(struct papr_scm_priv *p,
 765                                 union nd_pdsm_payload *payload)
 766 {
 767         int rc, size;
 768         u64 statval;
 769         struct papr_scm_perf_stat *stat;
 770         struct papr_scm_perf_stats *stats;
 771
 772         /* Silently fail if fetching performance metrics isn't  supported */
 773         if (!p->stat_buffer_len)
 774                 return 0;
 775
 776         /* Allocate request buffer enough to hold single performance stat */
 777         size = sizeof(struct papr_scm_perf_stats) +
 778                 sizeof(struct papr_scm_perf_stat);
 779
 780         stats = kzalloc(size, GFP_KERNEL);
 781         if (!stats)
 782                 return -ENOMEM;
 783
 784         stat = &stats->scm_statistic[0];
 785         memcpy(&stat->stat_id, "MemLife ", sizeof(stat->stat_id));
 786         stat->stat_val = 0;
 787
 788         /* Fetch the fuel gauge and populate it in payload */
 789         rc = drc_pmem_query_stats(p, stats, 1);
 790         if (rc < 0) {
 791                 dev_dbg(&p->pdev->dev, "Err(%d) fetching fuel gauge\n", rc);
 792                 goto free_stats;
 793         }
 794
 795         statval = be64_to_cpu(stat->stat_val);
 796         dev_dbg(&p->pdev->dev,
 797                 "Fetched fuel-gauge %llu", statval);
 798         payload->health.extension_flags |=
 799                 PDSM_DIMM_HEALTH_RUN_GAUGE_VALID;
 800         payload->health.dimm_fuel_gauge = statval;
 801
 802         rc = sizeof(struct nd_papr_pdsm_health);
 803
 804 free_stats:
 805         kfree(stats);
 806         return rc;
 807 }
 808
 809 /* Add the dirty-shutdown-counter value to the pdsm */
 810 static int papr_pdsm_dsc(struct papr_scm_priv *p,
 811                          union nd_pdsm_payload *payload)
 812 {
 813         payload->health.extension_flags |= PDSM_DIMM_DSC_VALID;
 814         payload->health.dimm_dsc = p->dirty_shutdown_counter;
 815
 816         return sizeof(struct nd_papr_pdsm_health);
 817 }
 818
 819 /* Fetch the DIMM health info and populate it in provided package. */
 820 static int papr_pdsm_health(struct papr_scm_priv *p,
 821                             union nd_pdsm_payload *payload)
 822 {
 823         int rc;
 824
 825         /* Ensure dimm health mutex is taken preventing concurrent access */
 826         rc = mutex_lock_interruptible(&p->health_mutex);
 827         if (rc)
 828                 goto out;
 829
 830         /* Always fetch upto date dimm health data ignoring cached values */
 831         rc = __drc_pmem_query_health(p);
 832         if (rc) {
 833                 mutex_unlock(&p->health_mutex);
 834                 goto out;
 835         }
 836
 837         /* update health struct with various flags derived from health bitmap */
 838         payload->health = (struct nd_papr_pdsm_health) {
 839                 .extension_flags = 0,
 840                 .dimm_unarmed = !!(p->health_bitmap & PAPR_PMEM_UNARMED_MASK),
 841                 .dimm_bad_shutdown = !!(p->health_bitmap & PAPR_PMEM_BAD_SHUTDOWN_MASK),
 842                 .dimm_bad_restore = !!(p->health_bitmap & PAPR_PMEM_BAD_RESTORE_MASK),
 843                 .dimm_scrubbed = !!(p->health_bitmap & PAPR_PMEM_SCRUBBED_AND_LOCKED),
 844                 .dimm_locked = !!(p->health_bitmap & PAPR_PMEM_SCRUBBED_AND_LOCKED),
 845                 .dimm_encrypted = !!(p->health_bitmap & PAPR_PMEM_ENCRYPTED),
 846                 .dimm_health = PAPR_PDSM_DIMM_HEALTHY,
 847         };
 848
 849         /* Update field dimm_health based on health_bitmap flags */
 850         if (p->health_bitmap & PAPR_PMEM_HEALTH_FATAL)
 851                 payload->health.dimm_health = PAPR_PDSM_DIMM_FATAL;
 852         else if (p->health_bitmap & PAPR_PMEM_HEALTH_CRITICAL)
 853                 payload->health.dimm_health = PAPR_PDSM_DIMM_CRITICAL;
 854         else if (p->health_bitmap & PAPR_PMEM_HEALTH_UNHEALTHY)
 855                 payload->health.dimm_health = PAPR_PDSM_DIMM_UNHEALTHY;
 856
 857         /* struct populated hence can release the mutex now */
 858         mutex_unlock(&p->health_mutex);
 859
 860         /* Populate the fuel gauge meter in the payload */
 861         papr_pdsm_fuel_gauge(p, payload);
 862         /* Populate the dirty-shutdown-counter field */
 863         papr_pdsm_dsc(p, payload);
 864
 865         rc = sizeof(struct nd_papr_pdsm_health);
 866
 867 out:
 868         return rc;
 869 }
 870
 871 /* Inject a smart error Add the dirty-shutdown-counter value to the pdsm */
 872 static int papr_pdsm_smart_inject(struct papr_scm_priv *p,
 873                                   union nd_pdsm_payload *payload)
 874 {
 875         int rc;
 876         u32 supported_flags = 0;
 877         u64 inject_mask = 0, clear_mask = 0;
 878         u64 mask;
 879
 880         /* Check for individual smart error flags and update inject/clear masks */
 881         if (payload->smart_inject.flags & PDSM_SMART_INJECT_HEALTH_FATAL) {
 882                 supported_flags |= PDSM_SMART_INJECT_HEALTH_FATAL;
 883                 if (payload->smart_inject.fatal_enable)
 884                         inject_mask |= PAPR_PMEM_HEALTH_FATAL;
 885                 else
 886                         clear_mask |= PAPR_PMEM_HEALTH_FATAL;
 887         }
 888
 889         if (payload->smart_inject.flags & PDSM_SMART_INJECT_BAD_SHUTDOWN) {
 890                 supported_flags |= PDSM_SMART_INJECT_BAD_SHUTDOWN;
 891                 if (payload->smart_inject.unsafe_shutdown_enable)
 892                         inject_mask |= PAPR_PMEM_SHUTDOWN_DIRTY;
 893                 else
 894                         clear_mask |= PAPR_PMEM_SHUTDOWN_DIRTY;
 895         }
 896
 897         dev_dbg(&p->pdev->dev, "[Smart-inject] inject_mask=%#llx clear_mask=%#llx\n",
 898                 inject_mask, clear_mask);
 899
 900         /* Prevent concurrent access to dimm health bitmap related members */
 901         rc = mutex_lock_interruptible(&p->health_mutex);
 902         if (rc)
 903                 return rc;
 904
 905         /* Use inject/clear masks to set health_bitmap_inject_mask */
 906         mask = READ_ONCE(p->health_bitmap_inject_mask);
 907         mask = (mask & ~clear_mask) | inject_mask;
 908         WRITE_ONCE(p->health_bitmap_inject_mask, mask);
 909
 910         /* Invalidate cached health bitmap */
 911         p->lasthealth_jiffies = 0;
 912
 913         mutex_unlock(&p->health_mutex);
 914
 915         /* Return the supported flags back to userspace */
 916         payload->smart_inject.flags = supported_flags;
 917
 918         return sizeof(struct nd_papr_pdsm_health);
 919 }
 920
 921 /*
 922  * 'struct pdsm_cmd_desc'
 923  * Identifies supported PDSMs' expected length of in/out payloads
 924  * and pdsm service function.
 925  *
 926  * size_in      : Size of input payload if any in the PDSM request.
 927  * size_out     : Size of output payload if any in the PDSM request.
 928  * service      : Service function for the PDSM request. Return semantics:
 929  *                rc < 0 : Error servicing PDSM and rc indicates the error.
 930  *                rc >=0 : Serviced successfully and 'rc' indicate number of
 931  *                      bytes written to payload.
 932  */
 933 struct pdsm_cmd_desc {
 934         u32 size_in;
 935         u32 size_out;
 936         int (*service)(struct papr_scm_priv *dimm,
 937                        union nd_pdsm_payload *payload);
 938 };
 939
 940 /* Holds all supported PDSMs' command descriptors */
 941 static const struct pdsm_cmd_desc __pdsm_cmd_descriptors[] = {
 942         [PAPR_PDSM_MIN] = {
 943                 .size_in = 0,
 944                 .size_out = 0,
 945                 .service = NULL,
 946         },
 947         /* New PDSM command descriptors to be added below */
 948
 949         [PAPR_PDSM_HEALTH] = {
 950                 .size_in = 0,
 951                 .size_out = sizeof(struct nd_papr_pdsm_health),
 952                 .service = papr_pdsm_health,
 953         },
 954
 955         [PAPR_PDSM_SMART_INJECT] = {
 956                 .size_in = sizeof(struct nd_papr_pdsm_smart_inject),
 957                 .size_out = sizeof(struct nd_papr_pdsm_smart_inject),
 958                 .service = papr_pdsm_smart_inject,
 959         },
 960         /* Empty */
 961         [PAPR_PDSM_MAX] = {
 962                 .size_in = 0,
 963                 .size_out = 0,
 964                 .service = NULL,
 965         },
 966 };
 967
 968 /* Given a valid pdsm cmd return its command descriptor else return NULL */
 969 static inline const struct pdsm_cmd_desc *pdsm_cmd_desc(enum papr_pdsm cmd)
 970 {
 971         if (cmd >= 0 || cmd < ARRAY_SIZE(__pdsm_cmd_descriptors))
 972                 return &__pdsm_cmd_descriptors[cmd];
 973
 974         return NULL;
 975 }
 976
 977 /*
 978  * For a given pdsm request call an appropriate service function.
 979  * Returns errors if any while handling the pdsm command package.
 980  */
 981 static int papr_scm_service_pdsm(struct papr_scm_priv *p,
 982                                  struct nd_cmd_pkg *pkg)
 983 {
 984         /* Get the PDSM header and PDSM command */
 985         struct nd_pkg_pdsm *pdsm_pkg = (struct nd_pkg_pdsm *)pkg->nd_payload;
 986         enum papr_pdsm pdsm = (enum papr_pdsm)pkg->nd_command;
 987         const struct pdsm_cmd_desc *pdsc;
 988         int rc;
 989
 990         /* Fetch corresponding pdsm descriptor for validation and servicing */
 991         pdsc = pdsm_cmd_desc(pdsm);
 992
 993         /* Validate pdsm descriptor */
 994         /* Ensure that reserved fields are 0 */
 995         if (pdsm_pkg->reserved[0] || pdsm_pkg->reserved[1]) {
 996                 dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Invalid reserved field\n",
 997                         pdsm);
 998                 return -EINVAL;
 999         }
1000
1001         /* If pdsm expects some input, then ensure that the size_in matches */
1002         if (pdsc->size_in &&
1003             pkg->nd_size_in != (pdsc->size_in + ND_PDSM_HDR_SIZE)) {
1004                 dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Mismatched size_in=%d\n",
1005                         pdsm, pkg->nd_size_in);
1006                 return -EINVAL;
1007         }
1008
1009         /* If pdsm wants to return data, then ensure that  size_out matches */
1010         if (pdsc->size_out &&
1011             pkg->nd_size_out != (pdsc->size_out + ND_PDSM_HDR_SIZE)) {
1012                 dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Mismatched size_out=%d\n",
1013                         pdsm, pkg->nd_size_out);
1014                 return -EINVAL;
1015         }
1016
1017         /* Service the pdsm */
1018         if (pdsc->service) {
1019                 dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Servicing..\n", pdsm);
1020
1021                 rc = pdsc->service(p, &pdsm_pkg->payload);
1022
1023                 if (rc < 0) {
1024                         /* error encountered while servicing pdsm */
1025                         pdsm_pkg->cmd_status = rc;
1026                         pkg->nd_fw_size = ND_PDSM_HDR_SIZE;
1027                 } else {
1028                         /* pdsm serviced and 'rc' bytes written to payload */
1029                         pdsm_pkg->cmd_status = 0;
1030                         pkg->nd_fw_size = ND_PDSM_HDR_SIZE + rc;
1031                 }
1032         } else {
1033                 dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Unsupported PDSM request\n",
1034                         pdsm);
1035                 pdsm_pkg->cmd_status = -ENOENT;
1036                 pkg->nd_fw_size = ND_PDSM_HDR_SIZE;
1037         }
1038
1039         return pdsm_pkg->cmd_status;
1040 }
1041
1042 static int papr_scm_ndctl(struct nvdimm_bus_descriptor *nd_desc,
1043                           struct nvdimm *nvdimm, unsigned int cmd, void *buf,
1044                           unsigned int buf_len, int *cmd_rc)
1045 {
1046         struct nd_cmd_get_config_size *get_size_hdr;
1047         struct nd_cmd_pkg *call_pkg = NULL;
1048         struct papr_scm_priv *p;
1049         int rc;
1050
1051         rc = is_cmd_valid(nvdimm, cmd, buf, buf_len);
1052         if (rc) {
1053                 pr_debug("Invalid cmd=0x%x. Err=%d\n", cmd, rc);
1054                 return rc;
1055         }
1056
1057         /* Use a local variable in case cmd_rc pointer is NULL */
1058         if (!cmd_rc)
1059                 cmd_rc = &rc;
1060
1061         p = nvdimm_provider_data(nvdimm);
1062
1063         switch (cmd) {
1064         case ND_CMD_GET_CONFIG_SIZE:
1065                 get_size_hdr = buf;
1066
1067                 get_size_hdr->status = 0;
1068                 get_size_hdr->max_xfer = 8;
1069                 get_size_hdr->config_size = p->metadata_size;
1070                 *cmd_rc = 0;
1071                 break;
1072
1073         case ND_CMD_GET_CONFIG_DATA:
1074                 *cmd_rc = papr_scm_meta_get(p, buf);
1075                 break;
1076
1077         case ND_CMD_SET_CONFIG_DATA:
1078                 *cmd_rc = papr_scm_meta_set(p, buf);
1079                 break;
1080
1081         case ND_CMD_CALL:
1082                 call_pkg = (struct nd_cmd_pkg *)buf;
1083                 *cmd_rc = papr_scm_service_pdsm(p, call_pkg);
1084                 break;
1085
1086         default:
1087                 dev_dbg(&p->pdev->dev, "Unknown command = %d\n", cmd);
1088                 return -EINVAL;
1089         }
1090
1091         dev_dbg(&p->pdev->dev, "returned with cmd_rc = %d\n", *cmd_rc);
1092
1093         return 0;
1094 }
1095
1096 static ssize_t health_bitmap_inject_show(struct device *dev,
1097                                          struct device_attribute *attr,
1098                                          char *buf)
1099 {
1100         struct nvdimm *dimm = to_nvdimm(dev);
1101         struct papr_scm_priv *p = nvdimm_provider_data(dimm);
1102
1103         return sprintf(buf, "%#llx\n",
1104                        READ_ONCE(p->health_bitmap_inject_mask));
1105 }
1106
1107 static DEVICE_ATTR_ADMIN_RO(health_bitmap_inject);
1108
1109 static ssize_t perf_stats_show(struct device *dev,
1110                                struct device_attribute *attr, char *buf)
1111 {
1112         int index;
1113         ssize_t rc;
1114         struct seq_buf s;
1115         struct papr_scm_perf_stat *stat;
1116         struct papr_scm_perf_stats *stats;
1117         struct nvdimm *dimm = to_nvdimm(dev);
1118         struct papr_scm_priv *p = nvdimm_provider_data(dimm);
1119
1120         if (!p->stat_buffer_len)
1121                 return -ENOENT;
1122
1123         /* Allocate the buffer for phyp where stats are written */
1124         stats = kzalloc(p->stat_buffer_len, GFP_KERNEL);
1125         if (!stats)
1126                 return -ENOMEM;
1127
1128         /* Ask phyp to return all dimm perf stats */
1129         rc = drc_pmem_query_stats(p, stats, 0);
1130         if (rc)
1131                 goto free_stats;
1132         /*
1133          * Go through the returned output buffer and print stats and
1134          * values. Since stat_id is essentially a char string of
1135          * 8 bytes, simply use the string format specifier to print it.
1136          */
1137         seq_buf_init(&s, buf, PAGE_SIZE);
1138         for (index = 0, stat = stats->scm_statistic;
1139              index < be32_to_cpu(stats->num_statistics);
1140              ++index, ++stat) {
1141                 seq_buf_printf(&s, "%.8s = 0x%016llX\n",
1142                                stat->stat_id,
1143                                be64_to_cpu(stat->stat_val));
1144         }
1145
1146 free_stats:
1147         kfree(stats);
1148         return rc ? rc : (ssize_t)seq_buf_used(&s);
1149 }
1150 static DEVICE_ATTR_ADMIN_RO(perf_stats);
1151
1152 static ssize_t flags_show(struct device *dev,
1153                           struct device_attribute *attr, char *buf)
1154 {
1155         struct nvdimm *dimm = to_nvdimm(dev);
1156         struct papr_scm_priv *p = nvdimm_provider_data(dimm);
1157         struct seq_buf s;
1158         u64 health;
1159         int rc;
1160
1161         rc = drc_pmem_query_health(p);
1162         if (rc)
1163                 return rc;
1164
1165         /* Copy health_bitmap locally, check masks & update out buffer */
1166         health = READ_ONCE(p->health_bitmap);
1167
1168         seq_buf_init(&s, buf, PAGE_SIZE);
1169         if (health & PAPR_PMEM_UNARMED_MASK)
1170                 seq_buf_printf(&s, "not_armed ");
1171
1172         if (health & PAPR_PMEM_BAD_SHUTDOWN_MASK)
1173                 seq_buf_printf(&s, "flush_fail ");
1174
1175         if (health & PAPR_PMEM_BAD_RESTORE_MASK)
1176                 seq_buf_printf(&s, "restore_fail ");
1177
1178         if (health & PAPR_PMEM_ENCRYPTED)
1179                 seq_buf_printf(&s, "encrypted ");
1180
1181         if (health & PAPR_PMEM_SMART_EVENT_MASK)
1182                 seq_buf_printf(&s, "smart_notify ");
1183
1184         if (health & PAPR_PMEM_SCRUBBED_AND_LOCKED)
1185                 seq_buf_printf(&s, "scrubbed locked ");
1186
1187         if (seq_buf_used(&s))
1188                 seq_buf_printf(&s, "\n");
1189
1190         return seq_buf_used(&s);
1191 }
1192 DEVICE_ATTR_RO(flags);
1193
1194 static ssize_t dirty_shutdown_show(struct device *dev,
1195                           struct device_attribute *attr, char *buf)
1196 {
1197         struct nvdimm *dimm = to_nvdimm(dev);
1198         struct papr_scm_priv *p = nvdimm_provider_data(dimm);
1199
1200         return sysfs_emit(buf, "%llu\n", p->dirty_shutdown_counter);
1201 }
1202 DEVICE_ATTR_RO(dirty_shutdown);
1203
1204 static umode_t papr_nd_attribute_visible(struct kobject *kobj,
1205                                          struct attribute *attr, int n)
1206 {
1207         struct device *dev = kobj_to_dev(kobj);
1208         struct nvdimm *nvdimm = to_nvdimm(dev);
1209         struct papr_scm_priv *p = nvdimm_provider_data(nvdimm);
1210
1211         /* For if perf-stats not available remove perf_stats sysfs */
1212         if (attr == &dev_attr_perf_stats.attr && p->stat_buffer_len == 0)
1213                 return 0;
1214
1215         return attr->mode;
1216 }
1217
1218 /* papr_scm specific dimm attributes */
1219 static struct attribute *papr_nd_attributes[] = {
1220         &dev_attr_flags.attr,
1221         &dev_attr_perf_stats.attr,
1222         &dev_attr_dirty_shutdown.attr,
1223         &dev_attr_health_bitmap_inject.attr,
1224         NULL,
1225 };
1226
1227 static const struct attribute_group papr_nd_attribute_group = {
1228         .name = "papr",
1229         .is_visible = papr_nd_attribute_visible,
1230         .attrs = papr_nd_attributes,
1231 };
1232
1233 static const struct attribute_group *papr_nd_attr_groups[] = {
1234         &papr_nd_attribute_group,
1235         NULL,
1236 };
1237
1238 static int papr_scm_nvdimm_init(struct papr_scm_priv *p)
1239 {
1240         struct device *dev = &p->pdev->dev;
1241         struct nd_mapping_desc mapping;
1242         struct nd_region_desc ndr_desc;
1243         unsigned long dimm_flags;
1244         int target_nid, online_nid;
1245
1246         p->bus_desc.ndctl = papr_scm_ndctl;
1247         p->bus_desc.module = THIS_MODULE;
1248         p->bus_desc.of_node = p->pdev->dev.of_node;
1249         p->bus_desc.provider_name = kstrdup(p->pdev->name, GFP_KERNEL);
1250
1251         /* Set the dimm command family mask to accept PDSMs */
1252         set_bit(NVDIMM_FAMILY_PAPR, &p->bus_desc.dimm_family_mask);
1253
1254         if (!p->bus_desc.provider_name)
1255                 return -ENOMEM;
1256
1257         p->bus = nvdimm_bus_register(NULL, &p->bus_desc);
1258         if (!p->bus) {
1259                 dev_err(dev, "Error creating nvdimm bus %pOF\n", p->dn);
1260                 kfree(p->bus_desc.provider_name);
1261                 return -ENXIO;
1262         }
1263
1264         dimm_flags = 0;
1265         set_bit(NDD_LABELING, &dimm_flags);
1266
1267         /*
1268          * Check if the nvdimm is unarmed. No locking needed as we are still
1269          * initializing. Ignore error encountered if any.
1270          */
1271         __drc_pmem_query_health(p);
1272
1273         if (p->health_bitmap & PAPR_PMEM_UNARMED_MASK)
1274                 set_bit(NDD_UNARMED, &dimm_flags);
1275
1276         p->nvdimm = nvdimm_create(p->bus, p, papr_nd_attr_groups,
1277                                   dimm_flags, PAPR_SCM_DIMM_CMD_MASK, 0, NULL);
1278         if (!p->nvdimm) {
1279                 dev_err(dev, "Error creating DIMM object for %pOF\n", p->dn);
1280                 goto err;
1281         }
1282
1283         if (nvdimm_bus_check_dimm_count(p->bus, 1))
1284                 goto err;
1285
1286         /* now add the region */
1287
1288         memset(&mapping, 0, sizeof(mapping));
1289         mapping.nvdimm = p->nvdimm;
1290         mapping.start = 0;
1291         mapping.size = p->blocks * p->block_size; // XXX: potential overflow?
1292
1293         memset(&ndr_desc, 0, sizeof(ndr_desc));
1294         target_nid = dev_to_node(&p->pdev->dev);
1295         online_nid = numa_map_to_online_node(target_nid);
1296         ndr_desc.numa_node = online_nid;
1297         ndr_desc.target_node = target_nid;
1298         ndr_desc.res = &p->res;
1299         ndr_desc.of_node = p->dn;
1300         ndr_desc.provider_data = p;
1301         ndr_desc.mapping = &mapping;
1302         ndr_desc.num_mappings = 1;
1303         ndr_desc.nd_set = &p->nd_set;
1304
1305         if (p->hcall_flush_required) {
1306                 set_bit(ND_REGION_ASYNC, &ndr_desc.flags);
1307                 ndr_desc.flush = papr_scm_pmem_flush;
1308         }
1309
1310         if (p->is_volatile)
1311                 p->region = nvdimm_volatile_region_create(p->bus, &ndr_desc);
1312         else {
1313                 set_bit(ND_REGION_PERSIST_MEMCTRL, &ndr_desc.flags);
1314                 p->region = nvdimm_pmem_region_create(p->bus, &ndr_desc);
1315         }
1316         if (!p->region) {
1317                 dev_err(dev, "Error registering region %pR from %pOF\n",
1318                                 ndr_desc.res, p->dn);
1319                 goto err;
1320         }
1321         if (target_nid != online_nid)
1322                 dev_info(dev, "Region registered with target node %d and online node %d",
1323                          target_nid, online_nid);
1324
1325         mutex_lock(&papr_ndr_lock);
1326         list_add_tail(&p->region_list, &papr_nd_regions);
1327         mutex_unlock(&papr_ndr_lock);
1328
1329         return 0;
1330
1331 err:    nvdimm_bus_unregister(p->bus);
1332         kfree(p->bus_desc.provider_name);
1333         return -ENXIO;
1334 }
1335
1336 static void papr_scm_add_badblock(struct nd_region *region,
1337                                   struct nvdimm_bus *bus, u64 phys_addr)
1338 {
1339         u64 aligned_addr = ALIGN_DOWN(phys_addr, L1_CACHE_BYTES);
1340
1341         if (nvdimm_bus_add_badrange(bus, aligned_addr, L1_CACHE_BYTES)) {
1342                 pr_err("Bad block registration for 0x%llx failed\n", phys_addr);
1343                 return;
1344         }
1345
1346         pr_debug("Add memory range (0x%llx - 0x%llx) as bad range\n",
1347                  aligned_addr, aligned_addr + L1_CACHE_BYTES);
1348
1349         nvdimm_region_notify(region, NVDIMM_REVALIDATE_POISON);
1350 }
1351
1352 static int handle_mce_ue(struct notifier_block *nb, unsigned long val,
1353                          void *data)
1354 {
1355         struct machine_check_event *evt = data;
1356         struct papr_scm_priv *p;
1357         u64 phys_addr;
1358         bool found = false;
1359
1360         if (evt->error_type != MCE_ERROR_TYPE_UE)
1361                 return NOTIFY_DONE;
1362
1363         if (list_empty(&papr_nd_regions))
1364                 return NOTIFY_DONE;
1365
1366         /*
1367          * The physical address obtained here is PAGE_SIZE aligned, so get the
1368          * exact address from the effective address
1369          */
1370         phys_addr = evt->u.ue_error.physical_address +
1371                         (evt->u.ue_error.effective_address & ~PAGE_MASK);
1372
1373         if (!evt->u.ue_error.physical_address_provided ||
1374             !is_zone_device_page(pfn_to_page(phys_addr >> PAGE_SHIFT)))
1375                 return NOTIFY_DONE;
1376
1377         /* mce notifier is called from a process context, so mutex is safe */
1378         mutex_lock(&papr_ndr_lock);
1379         list_for_each_entry(p, &papr_nd_regions, region_list) {
1380                 if (phys_addr >= p->res.start && phys_addr <= p->res.end) {
1381                         found = true;
1382                         break;
1383                 }
1384         }
1385
1386         if (found)
1387                 papr_scm_add_badblock(p->region, p->bus, phys_addr);
1388
1389         mutex_unlock(&papr_ndr_lock);
1390
1391         return found ? NOTIFY_OK : NOTIFY_DONE;
1392 }
1393
1394 static struct notifier_block mce_ue_nb = {
1395         .notifier_call = handle_mce_ue
1396 };
1397
1398 static int papr_scm_probe(struct platform_device *pdev)
1399 {
1400         struct device_node *dn = pdev->dev.of_node;
1401         u32 drc_index, metadata_size;
1402         u64 blocks, block_size;
1403         struct papr_scm_priv *p;
1404         u8 uuid_raw[UUID_SIZE];
1405         const char *uuid_str;
1406         ssize_t stat_size;
1407         uuid_t uuid;
1408         int rc;
1409
1410         /* check we have all the required DT properties */
1411         if (of_property_read_u32(dn, "ibm,my-drc-index", &drc_index)) {
1412                 dev_err(&pdev->dev, "%pOF: missing drc-index!\n", dn);
1413                 return -ENODEV;
1414         }
1415
1416         if (of_property_read_u64(dn, "ibm,block-size", &block_size)) {
1417                 dev_err(&pdev->dev, "%pOF: missing block-size!\n", dn);
1418                 return -ENODEV;
1419         }
1420
1421         if (of_property_read_u64(dn, "ibm,number-of-blocks", &blocks)) {
1422                 dev_err(&pdev->dev, "%pOF: missing number-of-blocks!\n", dn);
1423                 return -ENODEV;
1424         }
1425
1426         if (of_property_read_string(dn, "ibm,unit-guid", &uuid_str)) {
1427                 dev_err(&pdev->dev, "%pOF: missing unit-guid!\n", dn);
1428                 return -ENODEV;
1429         }
1430
1431         /*
1432          * open firmware platform device create won't update the NUMA
1433          * distance table. For PAPR SCM devices we use numa_map_to_online_node()
1434          * to find the nearest online NUMA node and that requires correct
1435          * distance table information.
1436          */
1437         update_numa_distance(dn);
1438
1439         p = kzalloc(sizeof(*p), GFP_KERNEL);
1440         if (!p)
1441                 return -ENOMEM;
1442
1443         /* Initialize the dimm mutex */
1444         mutex_init(&p->health_mutex);
1445
1446         /* optional DT properties */
1447         of_property_read_u32(dn, "ibm,metadata-size", &metadata_size);
1448
1449         p->dn = dn;
1450         p->drc_index = drc_index;
1451         p->block_size = block_size;
1452         p->blocks = blocks;
1453         p->is_volatile = !of_property_read_bool(dn, "ibm,cache-flush-required");
1454         p->hcall_flush_required = of_property_read_bool(dn, "ibm,hcall-flush-required");
1455
1456         if (of_property_read_u64(dn, "ibm,persistence-failed-count",
1457                                  &p->dirty_shutdown_counter))
1458                 p->dirty_shutdown_counter = 0;
1459
1460         /* We just need to ensure that set cookies are unique across */
1461         uuid_parse(uuid_str, &uuid);
1462
1463         /*
1464          * The cookie1 and cookie2 are not really little endian.
1465          * We store a raw buffer representation of the
1466          * uuid string so that we can compare this with the label
1467          * area cookie irrespective of the endian configuration
1468          * with which the kernel is built.
1469          *
1470          * Historically we stored the cookie in the below format.
1471          * for a uuid string 72511b67-0b3b-42fd-8d1d-5be3cae8bcaa
1472          *      cookie1 was 0xfd423b0b671b5172
1473          *      cookie2 was 0xaabce8cae35b1d8d
1474          */
1475         export_uuid(uuid_raw, &uuid);
1476         p->nd_set.cookie1 = get_unaligned_le64(&uuid_raw[0]);
1477         p->nd_set.cookie2 = get_unaligned_le64(&uuid_raw[8]);
1478
1479         /* might be zero */
1480         p->metadata_size = metadata_size;
1481         p->pdev = pdev;
1482
1483         /* request the hypervisor to bind this region to somewhere in memory */
1484         rc = drc_pmem_bind(p);
1485
1486         /* If phyp says drc memory still bound then force unbound and retry */
1487         if (rc == H_OVERLAP)
1488                 rc = drc_pmem_query_n_bind(p);
1489
1490         if (rc != H_SUCCESS) {
1491                 dev_err(&p->pdev->dev, "bind err: %d\n", rc);
1492                 rc = -ENXIO;
1493                 goto err;
1494         }
1495
1496         /* setup the resource for the newly bound range */
1497         p->res.start = p->bound_addr;
1498         p->res.end   = p->bound_addr + p->blocks * p->block_size - 1;
1499         p->res.name  = pdev->name;
1500         p->res.flags = IORESOURCE_MEM;
1501
1502         /* Try retrieving the stat buffer and see if its supported */
1503         stat_size = drc_pmem_query_stats(p, NULL, 0);
1504         if (stat_size > 0) {
1505                 p->stat_buffer_len = stat_size;
1506                 dev_dbg(&p->pdev->dev, "Max perf-stat size %lu-bytes\n",
1507                         p->stat_buffer_len);
1508         }
1509
1510         rc = papr_scm_nvdimm_init(p);
1511         if (rc)
1512                 goto err2;
1513
1514         platform_set_drvdata(pdev, p);
1515         papr_scm_pmu_register(p);
1516
1517         return 0;
1518
1519 err2:   drc_pmem_unbind(p);
1520 err:    kfree(p);
1521         return rc;
1522 }
1523
1524 static int papr_scm_remove(struct platform_device *pdev)
1525 {
1526         struct papr_scm_priv *p = platform_get_drvdata(pdev);
1527
1528         mutex_lock(&papr_ndr_lock);
1529         list_del(&p->region_list);
1530         mutex_unlock(&papr_ndr_lock);
1531
1532         nvdimm_bus_unregister(p->bus);
1533         drc_pmem_unbind(p);
1534
1535         if (pdev->archdata.priv)
1536                 unregister_nvdimm_pmu(pdev->archdata.priv);
1537
1538         pdev->archdata.priv = NULL;
1539         kfree(p->bus_desc.provider_name);
1540         kfree(p);
1541
1542         return 0;
1543 }
1544
1545 static const struct of_device_id papr_scm_match[] = {
1546         { .compatible = "ibm,pmemory" },
1547         { .compatible = "ibm,pmemory-v2" },
1548         { },
1549 };
1550
1551 static struct platform_driver papr_scm_driver = {
1552         .probe = papr_scm_probe,
1553         .remove = papr_scm_remove,
1554         .driver = {
1555                 .name = "papr_scm",
1556                 .of_match_table = papr_scm_match,
1557         },
1558 };
1559
1560 static int __init papr_scm_init(void)
1561 {
1562         int ret;
1563
1564         ret = platform_driver_register(&papr_scm_driver);
1565         if (!ret)
1566                 mce_register_notifier(&mce_ue_nb);
1567
1568         return ret;
1569 }
1570 module_init(papr_scm_init);
1571
1572 static void __exit papr_scm_exit(void)
1573 {
1574         mce_unregister_notifier(&mce_ue_nb);
1575         platform_driver_unregister(&papr_scm_driver);
1576 }
1577 module_exit(papr_scm_exit);
1578
1579 MODULE_DEVICE_TABLE(of, papr_scm_match);
1580 MODULE_LICENSE("GPL");
1581 MODULE_AUTHOR("IBM Corporation");