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/seq_file.h>
  10#include <linux/slab.h>
  11#include <linux/ndctl.h>
  12#include <linux/sched.h>
  13#include <linux/libnvdimm.h>
  14#include <linux/platform_device.h>
  15#include <linux/delay.h>
  16#include <linux/seq_buf.h>
  17#include <linux/nd.h>
  18
  19#include <asm/plpar_wrappers.h>
  20#include <uapi/linux/papr_pdsm.h>
  21#include <linux/papr_scm.h>
  22#include <asm/mce.h>
  23#include <linux/unaligned.h>
  24#include <linux/perf_event.h>
  25
  26#define BIND_ANY_ADDR (~0ul)
  27
  28#define PAPR_SCM_DIMM_CMD_MASK \
  29	((1ul << ND_CMD_GET_CONFIG_SIZE) | \
  30	 (1ul << ND_CMD_GET_CONFIG_DATA) | \
  31	 (1ul << ND_CMD_SET_CONFIG_DATA) | \
  32	 (1ul << ND_CMD_CALL))
  33
  34/* Struct holding a single performance metric */
  35struct papr_scm_perf_stat {
  36	u8 stat_id[8];
  37	__be64 stat_val;
  38} __packed;
  39
  40/* Struct exchanged between kernel and PHYP for fetching drc perf stats */
  41struct papr_scm_perf_stats {
  42	u8 eye_catcher[8];
  43	/* Should be PAPR_SCM_PERF_STATS_VERSION */
  44	__be32 stats_version;
  45	/* Number of stats following */
  46	__be32 num_statistics;
  47	/* zero or more performance matrics */
  48	struct papr_scm_perf_stat scm_statistic[];
  49} __packed;
  50
  51/* private struct associated with each region */
  52struct papr_scm_priv {
  53	struct platform_device *pdev;
  54	struct device_node *dn;
  55	uint32_t drc_index;
  56	uint64_t blocks;
  57	uint64_t block_size;
  58	int metadata_size;
  59	bool is_volatile;
  60	bool hcall_flush_required;
  61
  62	uint64_t bound_addr;
  63
  64	struct nvdimm_bus_descriptor bus_desc;
  65	struct nvdimm_bus *bus;
  66	struct nvdimm *nvdimm;
  67	struct resource res;
  68	struct nd_region *region;
  69	struct nd_interleave_set nd_set;
  70	struct list_head region_list;
  71
  72	/* Protect dimm health data from concurrent read/writes */
  73	struct mutex health_mutex;
  74
  75	/* Last time the health information of the dimm was updated */
  76	unsigned long lasthealth_jiffies;
  77
  78	/* Health information for the dimm */
  79	u64 health_bitmap;
  80
  81	/* Holds the last known dirty shutdown counter value */
  82	u64 dirty_shutdown_counter;
  83
  84	/* length of the stat buffer as expected by phyp */
  85	size_t stat_buffer_len;
  86
  87	/* The bits which needs to be overridden */
  88	u64 health_bitmap_inject_mask;
  89};
  90
  91static int papr_scm_pmem_flush(struct nd_region *nd_region,
  92			       struct bio *bio __maybe_unused)
  93{
  94	struct papr_scm_priv *p = nd_region_provider_data(nd_region);
  95	unsigned long ret_buf[PLPAR_HCALL_BUFSIZE], token = 0;
  96	long rc;
  97
  98	dev_dbg(&p->pdev->dev, "flush drc 0x%x", p->drc_index);
  99
 100	do {
 101		rc = plpar_hcall(H_SCM_FLUSH, ret_buf, p->drc_index, token);
 102		token = ret_buf[0];
 103
 104		/* Check if we are stalled for some time */
 105		if (H_IS_LONG_BUSY(rc)) {
 106			msleep(get_longbusy_msecs(rc));
 107			rc = H_BUSY;
 108		} else if (rc == H_BUSY) {
 109			cond_resched();
 110		}
 111	} while (rc == H_BUSY);
 112
 113	if (rc) {
 114		dev_err(&p->pdev->dev, "flush error: %ld", rc);
 115		rc = -EIO;
 116	} else {
 117		dev_dbg(&p->pdev->dev, "flush drc 0x%x complete", p->drc_index);
 118	}
 119
 120	return rc;
 121}
 122
 123static LIST_HEAD(papr_nd_regions);
 124static DEFINE_MUTEX(papr_ndr_lock);
 125
 126static int drc_pmem_bind(struct papr_scm_priv *p)
 127{
 128	unsigned long ret[PLPAR_HCALL_BUFSIZE];
 129	uint64_t saved = 0;
 130	uint64_t token;
 131	int64_t rc;
 132
 133	/*
 134	 * When the hypervisor cannot map all the requested memory in a single
 135	 * hcall it returns H_BUSY and we call again with the token until
 136	 * we get H_SUCCESS. Aborting the retry loop before getting H_SUCCESS
 137	 * leave the system in an undefined state, so we wait.
 138	 */
 139	token = 0;
 140
 141	do {
 142		rc = plpar_hcall(H_SCM_BIND_MEM, ret, p->drc_index, 0,
 143				p->blocks, BIND_ANY_ADDR, token);
 144		token = ret[0];
 145		if (!saved)
 146			saved = ret[1];
 147		cond_resched();
 148	} while (rc == H_BUSY);
 149
 150	if (rc)
 151		return rc;
 152
 153	p->bound_addr = saved;
 154	dev_dbg(&p->pdev->dev, "bound drc 0x%x to 0x%lx\n",
 155		p->drc_index, (unsigned long)saved);
 156	return rc;
 157}
 158
 159static void drc_pmem_unbind(struct papr_scm_priv *p)
 160{
 161	unsigned long ret[PLPAR_HCALL_BUFSIZE];
 162	uint64_t token = 0;
 163	int64_t rc;
 164
 165	dev_dbg(&p->pdev->dev, "unbind drc 0x%x\n", p->drc_index);
 166
 167	/* NB: unbind has the same retry requirements as drc_pmem_bind() */
 168	do {
 169
 170		/* Unbind of all SCM resources associated with drcIndex */
 171		rc = plpar_hcall(H_SCM_UNBIND_ALL, ret, H_UNBIND_SCOPE_DRC,
 172				 p->drc_index, token);
 173		token = ret[0];
 174
 175		/* Check if we are stalled for some time */
 176		if (H_IS_LONG_BUSY(rc)) {
 177			msleep(get_longbusy_msecs(rc));
 178			rc = H_BUSY;
 179		} else if (rc == H_BUSY) {
 180			cond_resched();
 181		}
 182
 183	} while (rc == H_BUSY);
 184
 185	if (rc)
 186		dev_err(&p->pdev->dev, "unbind error: %lld\n", rc);
 187	else
 188		dev_dbg(&p->pdev->dev, "unbind drc 0x%x complete\n",
 189			p->drc_index);
 190
 191	return;
 192}
 193
 194static int drc_pmem_query_n_bind(struct papr_scm_priv *p)
 195{
 196	unsigned long start_addr;
 197	unsigned long end_addr;
 198	unsigned long ret[PLPAR_HCALL_BUFSIZE];
 199	int64_t rc;
 200
 201
 202	rc = plpar_hcall(H_SCM_QUERY_BLOCK_MEM_BINDING, ret,
 203			 p->drc_index, 0);
 204	if (rc)
 205		goto err_out;
 206	start_addr = ret[0];
 207
 208	/* Make sure the full region is bound. */
 209	rc = plpar_hcall(H_SCM_QUERY_BLOCK_MEM_BINDING, ret,
 210			 p->drc_index, p->blocks - 1);
 211	if (rc)
 212		goto err_out;
 213	end_addr = ret[0];
 214
 215	if ((end_addr - start_addr) != ((p->blocks - 1) * p->block_size))
 216		goto err_out;
 217
 218	p->bound_addr = start_addr;
 219	dev_dbg(&p->pdev->dev, "bound drc 0x%x to 0x%lx\n", p->drc_index, start_addr);
 220	return rc;
 221
 222err_out:
 223	dev_info(&p->pdev->dev,
 224		 "Failed to query, trying an unbind followed by bind");
 225	drc_pmem_unbind(p);
 226	return drc_pmem_bind(p);
 227}
 228
 229/*
 230 * Query the Dimm performance stats from PHYP and copy them (if returned) to
 231 * provided struct papr_scm_perf_stats instance 'stats' that can hold atleast
 232 * (num_stats + header) bytes.
 233 * - If buff_stats == NULL the return value is the size in bytes of the buffer
 234 * needed to hold all supported performance-statistics.
 235 * - If buff_stats != NULL and num_stats == 0 then we copy all known
 236 * performance-statistics to 'buff_stat' and expect to be large enough to
 237 * hold them.
 238 * - if buff_stats != NULL and num_stats > 0 then copy the requested
 239 * performance-statistics to buff_stats.
 240 */
 241static ssize_t drc_pmem_query_stats(struct papr_scm_priv *p,
 242				    struct papr_scm_perf_stats *buff_stats,
 243				    unsigned int num_stats)
 244{
 245	unsigned long ret[PLPAR_HCALL_BUFSIZE];
 246	size_t size;
 247	s64 rc;
 248
 249	/* Setup the out buffer */
 250	if (buff_stats) {
 251		memcpy(buff_stats->eye_catcher,
 252		       PAPR_SCM_PERF_STATS_EYECATCHER, 8);
 253		buff_stats->stats_version =
 254			cpu_to_be32(PAPR_SCM_PERF_STATS_VERSION);
 255		buff_stats->num_statistics =
 256			cpu_to_be32(num_stats);
 257
 258		/*
 259		 * Calculate the buffer size based on num-stats provided
 260		 * or use the prefetched max buffer length
 261		 */
 262		if (num_stats)
 263			/* Calculate size from the num_stats */
 264			size = sizeof(struct papr_scm_perf_stats) +
 265				num_stats * sizeof(struct papr_scm_perf_stat);
 266		else
 267			size = p->stat_buffer_len;
 268	} else {
 269		/* In case of no out buffer ignore the size */
 270		size = 0;
 271	}
 272
 273	/* Do the HCALL asking PHYP for info */
 274	rc = plpar_hcall(H_SCM_PERFORMANCE_STATS, ret, p->drc_index,
 275			 buff_stats ? virt_to_phys(buff_stats) : 0,
 276			 size);
 277
 278	/* Check if the error was due to an unknown stat-id */
 279	if (rc == H_PARTIAL) {
 280		dev_err(&p->pdev->dev,
 281			"Unknown performance stats, Err:0x%016lX\n", ret[0]);
 282		return -ENOENT;
 283	} else if (rc == H_AUTHORITY) {
 284		dev_info(&p->pdev->dev,
 285			 "Permission denied while accessing performance stats");
 286		return -EPERM;
 287	} else if (rc == H_UNSUPPORTED) {
 288		dev_dbg(&p->pdev->dev, "Performance stats unsupported\n");
 289		return -EOPNOTSUPP;
 290	} else if (rc != H_SUCCESS) {
 291		dev_err(&p->pdev->dev,
 292			"Failed to query performance stats, Err:%lld\n", rc);
 293		return -EIO;
 294
 295	} else if (!size) {
 296		/* Handle case where stat buffer size was requested */
 297		dev_dbg(&p->pdev->dev,
 298			"Performance stats size %ld\n", ret[0]);
 299		return ret[0];
 300	}
 301
 302	/* Successfully fetched the requested stats from phyp */
 303	dev_dbg(&p->pdev->dev,
 304		"Performance stats returned %d stats\n",
 305		be32_to_cpu(buff_stats->num_statistics));
 306	return 0;
 307}
 308
 309#ifdef CONFIG_PERF_EVENTS
 310#define to_nvdimm_pmu(_pmu)	container_of(_pmu, struct nvdimm_pmu, pmu)
 311
 312static const char * const nvdimm_events_map[] = {
 313	[1] = "CtlResCt",
 314	[2] = "CtlResTm",
 315	[3] = "PonSecs ",
 316	[4] = "MemLife ",
 317	[5] = "CritRscU",
 318	[6] = "HostLCnt",
 319	[7] = "HostSCnt",
 320	[8] = "HostSDur",
 321	[9] = "HostLDur",
 322	[10] = "MedRCnt ",
 323	[11] = "MedWCnt ",
 324	[12] = "MedRDur ",
 325	[13] = "MedWDur ",
 326	[14] = "CchRHCnt",
 327	[15] = "CchWHCnt",
 328	[16] = "FastWCnt",
 329};
 330
 331static int papr_scm_pmu_get_value(struct perf_event *event, struct device *dev, u64 *count)
 332{
 333	struct papr_scm_perf_stat *stat;
 334	struct papr_scm_perf_stats *stats;
 335	struct papr_scm_priv *p = dev_get_drvdata(dev);
 336	int rc, size;
 337
 338	/* Invalid eventcode */
 339	if (event->attr.config == 0 || event->attr.config >= ARRAY_SIZE(nvdimm_events_map))
 340		return -EINVAL;
 341
 342	/* Allocate request buffer enough to hold single performance stat */
 343	size = sizeof(struct papr_scm_perf_stats) +
 344		sizeof(struct papr_scm_perf_stat);
 345
 346	if (!p)
 347		return -EINVAL;
 348
 349	stats = kzalloc(size, GFP_KERNEL);
 350	if (!stats)
 351		return -ENOMEM;
 352
 353	stat = &stats->scm_statistic[0];
 354	memcpy(&stat->stat_id,
 355	       nvdimm_events_map[event->attr.config],
 356		sizeof(stat->stat_id));
 357	stat->stat_val = 0;
 358
 359	rc = drc_pmem_query_stats(p, stats, 1);
 360	if (rc < 0) {
 361		kfree(stats);
 362		return rc;
 363	}
 364
 365	*count = be64_to_cpu(stat->stat_val);
 366	kfree(stats);
 367	return 0;
 368}
 369
 370static int papr_scm_pmu_event_init(struct perf_event *event)
 371{
 372	struct nvdimm_pmu *nd_pmu = to_nvdimm_pmu(event->pmu);
 373	struct papr_scm_priv *p;
 374
 375	if (!nd_pmu)
 376		return -EINVAL;
 377
 378	/* test the event attr type for PMU enumeration */
 379	if (event->attr.type != event->pmu->type)
 380		return -ENOENT;
 381
 382	/* it does not support event sampling mode */
 383	if (is_sampling_event(event))
 384		return -EOPNOTSUPP;
 385
 386	/* no branch sampling */
 387	if (has_branch_stack(event))
 388		return -EOPNOTSUPP;
 389
 390	p = (struct papr_scm_priv *)nd_pmu->dev->driver_data;
 391	if (!p)
 392		return -EINVAL;
 393
 394	/* Invalid eventcode */
 395	if (event->attr.config == 0 || event->attr.config > 16)
 396		return -EINVAL;
 397
 398	return 0;
 399}
 400
 401static int papr_scm_pmu_add(struct perf_event *event, int flags)
 402{
 403	u64 count;
 404	int rc;
 405	struct nvdimm_pmu *nd_pmu = to_nvdimm_pmu(event->pmu);
 406
 407	if (!nd_pmu)
 408		return -EINVAL;
 409
 410	if (flags & PERF_EF_START) {
 411		rc = papr_scm_pmu_get_value(event, nd_pmu->dev, &count);
 412		if (rc)
 413			return rc;
 414
 415		local64_set(&event->hw.prev_count, count);
 416	}
 417
 418	return 0;
 419}
 420
 421static void papr_scm_pmu_read(struct perf_event *event)
 422{
 423	u64 prev, now;
 424	int rc;
 425	struct nvdimm_pmu *nd_pmu = to_nvdimm_pmu(event->pmu);
 426
 427	if (!nd_pmu)
 428		return;
 429
 430	rc = papr_scm_pmu_get_value(event, nd_pmu->dev, &now);
 431	if (rc)
 432		return;
 433
 434	prev = local64_xchg(&event->hw.prev_count, now);
 435	local64_add(now - prev, &event->count);
 436}
 437
 438static void papr_scm_pmu_del(struct perf_event *event, int flags)
 439{
 440	papr_scm_pmu_read(event);
 441}
 442
 443static void papr_scm_pmu_register(struct papr_scm_priv *p)
 444{
 445	struct nvdimm_pmu *nd_pmu;
 446	int rc, nodeid;
 447
 448	nd_pmu = kzalloc(sizeof(*nd_pmu), GFP_KERNEL);
 449	if (!nd_pmu) {
 450		rc = -ENOMEM;
 451		goto pmu_err_print;
 452	}
 453
 454	if (!p->stat_buffer_len) {
 455		rc = -ENOENT;
 456		goto pmu_check_events_err;
 457	}
 458
 459	nd_pmu->pmu.task_ctx_nr = perf_invalid_context;
 460	nd_pmu->pmu.name = nvdimm_name(p->nvdimm);
 461	nd_pmu->pmu.event_init = papr_scm_pmu_event_init;
 462	nd_pmu->pmu.read = papr_scm_pmu_read;
 463	nd_pmu->pmu.add = papr_scm_pmu_add;
 464	nd_pmu->pmu.del = papr_scm_pmu_del;
 465
 466	nd_pmu->pmu.capabilities = PERF_PMU_CAP_NO_INTERRUPT |
 467				PERF_PMU_CAP_NO_EXCLUDE;
 468
 469	/*updating the cpumask variable */
 470	nodeid = numa_map_to_online_node(dev_to_node(&p->pdev->dev));
 471	nd_pmu->arch_cpumask = *cpumask_of_node(nodeid);
 472
 473	rc = register_nvdimm_pmu(nd_pmu, p->pdev);
 474	if (rc)
 475		goto pmu_check_events_err;
 476
 477	/*
 478	 * Set archdata.priv value to nvdimm_pmu structure, to handle the
 479	 * unregistering of pmu device.
 480	 */
 481	p->pdev->archdata.priv = nd_pmu;
 482	return;
 483
 484pmu_check_events_err:
 485	kfree(nd_pmu);
 486pmu_err_print:
 487	dev_info(&p->pdev->dev, "nvdimm pmu didn't register rc=%d\n", rc);
 488}
 489
 490#else
 491static void papr_scm_pmu_register(struct papr_scm_priv *p) { }
 492#endif
 493
 494/*
 495 * Issue hcall to retrieve dimm health info and populate papr_scm_priv with the
 496 * health information.
 497 */
 498static int __drc_pmem_query_health(struct papr_scm_priv *p)
 499{
 500	unsigned long ret[PLPAR_HCALL_BUFSIZE];
 501	u64 bitmap = 0;
 502	long rc;
 503
 504	/* issue the hcall */
 505	rc = plpar_hcall(H_SCM_HEALTH, ret, p->drc_index);
 506	if (rc == H_SUCCESS)
 507		bitmap = ret[0] & ret[1];
 508	else if (rc == H_FUNCTION)
 509		dev_info_once(&p->pdev->dev,
 510			      "Hcall H_SCM_HEALTH not implemented, assuming empty health bitmap");
 511	else {
 512
 513		dev_err(&p->pdev->dev,
 514			"Failed to query health information, Err:%ld\n", rc);
 515		return -ENXIO;
 516	}
 517
 518	p->lasthealth_jiffies = jiffies;
 519	/* Allow injecting specific health bits via inject mask. */
 520	if (p->health_bitmap_inject_mask)
 521		bitmap = (bitmap & ~p->health_bitmap_inject_mask) |
 522			p->health_bitmap_inject_mask;
 523	WRITE_ONCE(p->health_bitmap, bitmap);
 524	dev_dbg(&p->pdev->dev,
 525		"Queried dimm health info. Bitmap:0x%016lx Mask:0x%016lx\n",
 526		ret[0], ret[1]);
 527
 528	return 0;
 529}
 530
 531/* Min interval in seconds for assuming stable dimm health */
 532#define MIN_HEALTH_QUERY_INTERVAL 60
 533
 534/* Query cached health info and if needed call drc_pmem_query_health */
 535static int drc_pmem_query_health(struct papr_scm_priv *p)
 536{
 537	unsigned long cache_timeout;
 538	int rc;
 539
 540	/* Protect concurrent modifications to papr_scm_priv */
 541	rc = mutex_lock_interruptible(&p->health_mutex);
 542	if (rc)
 543		return rc;
 544
 545	/* Jiffies offset for which the health data is assumed to be same */
 546	cache_timeout = p->lasthealth_jiffies +
 547		secs_to_jiffies(MIN_HEALTH_QUERY_INTERVAL);
 548
 549	/* Fetch new health info is its older than MIN_HEALTH_QUERY_INTERVAL */
 550	if (time_after(jiffies, cache_timeout))
 551		rc = __drc_pmem_query_health(p);
 552	else
 553		/* Assume cached health data is valid */
 554		rc = 0;
 555
 556	mutex_unlock(&p->health_mutex);
 557	return rc;
 558}
 559
 560static int papr_scm_meta_get(struct papr_scm_priv *p,
 561			     struct nd_cmd_get_config_data_hdr *hdr)
 562{
 563	unsigned long data[PLPAR_HCALL_BUFSIZE];
 564	unsigned long offset, data_offset;
 565	int len, read;
 566	int64_t ret;
 567
 568	if ((hdr->in_offset + hdr->in_length) > p->metadata_size)
 569		return -EINVAL;
 570
 571	for (len = hdr->in_length; len; len -= read) {
 572
 573		data_offset = hdr->in_length - len;
 574		offset = hdr->in_offset + data_offset;
 575
 576		if (len >= 8)
 577			read = 8;
 578		else if (len >= 4)
 579			read = 4;
 580		else if (len >= 2)
 581			read = 2;
 582		else
 583			read = 1;
 584
 585		ret = plpar_hcall(H_SCM_READ_METADATA, data, p->drc_index,
 586				  offset, read);
 587
 588		if (ret == H_PARAMETER) /* bad DRC index */
 589			return -ENODEV;
 590		if (ret)
 591			return -EINVAL; /* other invalid parameter */
 592
 593		switch (read) {
 594		case 8:
 595			*(uint64_t *)(hdr->out_buf + data_offset) = be64_to_cpu(data[0]);
 596			break;
 597		case 4:
 598			*(uint32_t *)(hdr->out_buf + data_offset) = be32_to_cpu(data[0] & 0xffffffff);
 599			break;
 600
 601		case 2:
 602			*(uint16_t *)(hdr->out_buf + data_offset) = be16_to_cpu(data[0] & 0xffff);
 603			break;
 604
 605		case 1:
 606			*(uint8_t *)(hdr->out_buf + data_offset) = (data[0] & 0xff);
 607			break;
 608		}
 609	}
 610	return 0;
 611}
 612
 613static int papr_scm_meta_set(struct papr_scm_priv *p,
 614			     struct nd_cmd_set_config_hdr *hdr)
 615{
 616	unsigned long offset, data_offset;
 617	int len, wrote;
 618	unsigned long data;
 619	__be64 data_be;
 620	int64_t ret;
 621
 622	if ((hdr->in_offset + hdr->in_length) > p->metadata_size)
 623		return -EINVAL;
 624
 625	for (len = hdr->in_length; len; len -= wrote) {
 626
 627		data_offset = hdr->in_length - len;
 628		offset = hdr->in_offset + data_offset;
 629
 630		if (len >= 8) {
 631			data = *(uint64_t *)(hdr->in_buf + data_offset);
 632			data_be = cpu_to_be64(data);
 633			wrote = 8;
 634		} else if (len >= 4) {
 635			data = *(uint32_t *)(hdr->in_buf + data_offset);
 636			data &= 0xffffffff;
 637			data_be = cpu_to_be32(data);
 638			wrote = 4;
 639		} else if (len >= 2) {
 640			data = *(uint16_t *)(hdr->in_buf + data_offset);
 641			data &= 0xffff;
 642			data_be = cpu_to_be16(data);
 643			wrote = 2;
 644		} else {
 645			data_be = *(uint8_t *)(hdr->in_buf + data_offset);
 646			data_be &= 0xff;
 647			wrote = 1;
 648		}
 649
 650		ret = plpar_hcall_norets(H_SCM_WRITE_METADATA, p->drc_index,
 651					 offset, data_be, wrote);
 652		if (ret == H_PARAMETER) /* bad DRC index */
 653			return -ENODEV;
 654		if (ret)
 655			return -EINVAL; /* other invalid parameter */
 656	}
 657
 658	return 0;
 659}
 660
 661/*
 662 * Do a sanity checks on the inputs args to dimm-control function and return
 663 * '0' if valid. Validation of PDSM payloads happens later in
 664 * papr_scm_service_pdsm.
 665 */
 666static int is_cmd_valid(struct nvdimm *nvdimm, unsigned int cmd, void *buf,
 667			unsigned int buf_len)
 668{
 669	unsigned long cmd_mask = PAPR_SCM_DIMM_CMD_MASK;
 670	struct nd_cmd_pkg *nd_cmd;
 671	struct papr_scm_priv *p;
 672	enum papr_pdsm pdsm;
 673
 674	/* Only dimm-specific calls are supported atm */
 675	if (!nvdimm)
 676		return -EINVAL;
 677
 678	/* get the provider data from struct nvdimm */
 679	p = nvdimm_provider_data(nvdimm);
 680
 681	if (!test_bit(cmd, &cmd_mask)) {
 682		dev_dbg(&p->pdev->dev, "Unsupported cmd=%u\n", cmd);
 683		return -EINVAL;
 684	}
 685
 686	/* For CMD_CALL verify pdsm request */
 687	if (cmd == ND_CMD_CALL) {
 688		/* Verify the envelope and envelop size */
 689		if (!buf ||
 690		    buf_len < (sizeof(struct nd_cmd_pkg) + ND_PDSM_HDR_SIZE)) {
 691			dev_dbg(&p->pdev->dev, "Invalid pkg size=%u\n",
 692				buf_len);
 693			return -EINVAL;
 694		}
 695
 696		/* Verify that the nd_cmd_pkg.nd_family is correct */
 697		nd_cmd = (struct nd_cmd_pkg *)buf;
 698
 699		if (nd_cmd->nd_family != NVDIMM_FAMILY_PAPR) {
 700			dev_dbg(&p->pdev->dev, "Invalid pkg family=0x%llx\n",
 701				nd_cmd->nd_family);
 702			return -EINVAL;
 703		}
 704
 705		pdsm = (enum papr_pdsm)nd_cmd->nd_command;
 706
 707		/* Verify if the pdsm command is valid */
 708		if (pdsm <= PAPR_PDSM_MIN || pdsm >= PAPR_PDSM_MAX) {
 709			dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Invalid PDSM\n",
 710				pdsm);
 711			return -EINVAL;
 712		}
 713
 714		/* Have enough space to hold returned 'nd_pkg_pdsm' header */
 715		if (nd_cmd->nd_size_out < ND_PDSM_HDR_SIZE) {
 716			dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Invalid payload\n",
 717				pdsm);
 718			return -EINVAL;
 719		}
 720	}
 721
 722	/* Let the command be further processed */
 723	return 0;
 724}
 725
 726static int papr_pdsm_fuel_gauge(struct papr_scm_priv *p,
 727				union nd_pdsm_payload *payload)
 728{
 729	int rc, size;
 730	u64 statval;
 731	struct papr_scm_perf_stat *stat;
 732	struct papr_scm_perf_stats *stats;
 733
 734	/* Silently fail if fetching performance metrics isn't  supported */
 735	if (!p->stat_buffer_len)
 736		return 0;
 737
 738	/* Allocate request buffer enough to hold single performance stat */
 739	size = sizeof(struct papr_scm_perf_stats) +
 740		sizeof(struct papr_scm_perf_stat);
 741
 742	stats = kzalloc(size, GFP_KERNEL);
 743	if (!stats)
 744		return -ENOMEM;
 745
 746	stat = &stats->scm_statistic[0];
 747	memcpy(&stat->stat_id, "MemLife ", sizeof(stat->stat_id));
 748	stat->stat_val = 0;
 749
 750	/* Fetch the fuel gauge and populate it in payload */
 751	rc = drc_pmem_query_stats(p, stats, 1);
 752	if (rc < 0) {
 753		dev_dbg(&p->pdev->dev, "Err(%d) fetching fuel gauge\n", rc);
 754		goto free_stats;
 755	}
 756
 757	statval = be64_to_cpu(stat->stat_val);
 758	dev_dbg(&p->pdev->dev,
 759		"Fetched fuel-gauge %llu", statval);
 760	payload->health.extension_flags |=
 761		PDSM_DIMM_HEALTH_RUN_GAUGE_VALID;
 762	payload->health.dimm_fuel_gauge = statval;
 763
 764	rc = sizeof(struct nd_papr_pdsm_health);
 765
 766free_stats:
 767	kfree(stats);
 768	return rc;
 769}
 770
 771/* Add the dirty-shutdown-counter value to the pdsm */
 772static int papr_pdsm_dsc(struct papr_scm_priv *p,
 773			 union nd_pdsm_payload *payload)
 774{
 775	payload->health.extension_flags |= PDSM_DIMM_DSC_VALID;
 776	payload->health.dimm_dsc = p->dirty_shutdown_counter;
 777
 778	return sizeof(struct nd_papr_pdsm_health);
 779}
 780
 781/* Fetch the DIMM health info and populate it in provided package. */
 782static int papr_pdsm_health(struct papr_scm_priv *p,
 783			    union nd_pdsm_payload *payload)
 784{
 785	int rc;
 786
 787	/* Ensure dimm health mutex is taken preventing concurrent access */
 788	rc = mutex_lock_interruptible(&p->health_mutex);
 789	if (rc)
 790		goto out;
 791
 792	/* Always fetch upto date dimm health data ignoring cached values */
 793	rc = __drc_pmem_query_health(p);
 794	if (rc) {
 795		mutex_unlock(&p->health_mutex);
 796		goto out;
 797	}
 798
 799	/* update health struct with various flags derived from health bitmap */
 800	payload->health = (struct nd_papr_pdsm_health) {
 801		.extension_flags = 0,
 802		.dimm_unarmed = !!(p->health_bitmap & PAPR_PMEM_UNARMED_MASK),
 803		.dimm_bad_shutdown = !!(p->health_bitmap & PAPR_PMEM_BAD_SHUTDOWN_MASK),
 804		.dimm_bad_restore = !!(p->health_bitmap & PAPR_PMEM_BAD_RESTORE_MASK),
 805		.dimm_scrubbed = !!(p->health_bitmap & PAPR_PMEM_SCRUBBED_AND_LOCKED),
 806		.dimm_locked = !!(p->health_bitmap & PAPR_PMEM_SCRUBBED_AND_LOCKED),
 807		.dimm_encrypted = !!(p->health_bitmap & PAPR_PMEM_ENCRYPTED),
 808		.dimm_health = PAPR_PDSM_DIMM_HEALTHY,
 809	};
 810
 811	/* Update field dimm_health based on health_bitmap flags */
 812	if (p->health_bitmap & PAPR_PMEM_HEALTH_FATAL)
 813		payload->health.dimm_health = PAPR_PDSM_DIMM_FATAL;
 814	else if (p->health_bitmap & PAPR_PMEM_HEALTH_CRITICAL)
 815		payload->health.dimm_health = PAPR_PDSM_DIMM_CRITICAL;
 816	else if (p->health_bitmap & PAPR_PMEM_HEALTH_UNHEALTHY)
 817		payload->health.dimm_health = PAPR_PDSM_DIMM_UNHEALTHY;
 818
 819	/* struct populated hence can release the mutex now */
 820	mutex_unlock(&p->health_mutex);
 821
 822	/* Populate the fuel gauge meter in the payload */
 823	papr_pdsm_fuel_gauge(p, payload);
 824	/* Populate the dirty-shutdown-counter field */
 825	papr_pdsm_dsc(p, payload);
 826
 827	rc = sizeof(struct nd_papr_pdsm_health);
 828
 829out:
 830	return rc;
 831}
 832
 833/* Inject a smart error Add the dirty-shutdown-counter value to the pdsm */
 834static int papr_pdsm_smart_inject(struct papr_scm_priv *p,
 835				  union nd_pdsm_payload *payload)
 836{
 837	int rc;
 838	u32 supported_flags = 0;
 839	u64 inject_mask = 0, clear_mask = 0;
 840	u64 mask;
 841
 842	/* Check for individual smart error flags and update inject/clear masks */
 843	if (payload->smart_inject.flags & PDSM_SMART_INJECT_HEALTH_FATAL) {
 844		supported_flags |= PDSM_SMART_INJECT_HEALTH_FATAL;
 845		if (payload->smart_inject.fatal_enable)
 846			inject_mask |= PAPR_PMEM_HEALTH_FATAL;
 847		else
 848			clear_mask |= PAPR_PMEM_HEALTH_FATAL;
 849	}
 850
 851	if (payload->smart_inject.flags & PDSM_SMART_INJECT_BAD_SHUTDOWN) {
 852		supported_flags |= PDSM_SMART_INJECT_BAD_SHUTDOWN;
 853		if (payload->smart_inject.unsafe_shutdown_enable)
 854			inject_mask |= PAPR_PMEM_SHUTDOWN_DIRTY;
 855		else
 856			clear_mask |= PAPR_PMEM_SHUTDOWN_DIRTY;
 857	}
 858
 859	dev_dbg(&p->pdev->dev, "[Smart-inject] inject_mask=%#llx clear_mask=%#llx\n",
 860		inject_mask, clear_mask);
 861
 862	/* Prevent concurrent access to dimm health bitmap related members */
 863	rc = mutex_lock_interruptible(&p->health_mutex);
 864	if (rc)
 865		return rc;
 866
 867	/* Use inject/clear masks to set health_bitmap_inject_mask */
 868	mask = READ_ONCE(p->health_bitmap_inject_mask);
 869	mask = (mask & ~clear_mask) | inject_mask;
 870	WRITE_ONCE(p->health_bitmap_inject_mask, mask);
 871
 872	/* Invalidate cached health bitmap */
 873	p->lasthealth_jiffies = 0;
 874
 875	mutex_unlock(&p->health_mutex);
 876
 877	/* Return the supported flags back to userspace */
 878	payload->smart_inject.flags = supported_flags;
 879
 880	return sizeof(struct nd_papr_pdsm_health);
 881}
 882
 883/*
 884 * 'struct pdsm_cmd_desc'
 885 * Identifies supported PDSMs' expected length of in/out payloads
 886 * and pdsm service function.
 887 *
 888 * size_in	: Size of input payload if any in the PDSM request.
 889 * size_out	: Size of output payload if any in the PDSM request.
 890 * service	: Service function for the PDSM request. Return semantics:
 891 *		  rc < 0 : Error servicing PDSM and rc indicates the error.
 892 *		  rc >=0 : Serviced successfully and 'rc' indicate number of
 893 *			bytes written to payload.
 894 */
 895struct pdsm_cmd_desc {
 896	u32 size_in;
 897	u32 size_out;
 898	int (*service)(struct papr_scm_priv *dimm,
 899		       union nd_pdsm_payload *payload);
 900};
 901
 902/* Holds all supported PDSMs' command descriptors */
 903static const struct pdsm_cmd_desc __pdsm_cmd_descriptors[] = {
 904	[PAPR_PDSM_MIN] = {
 905		.size_in = 0,
 906		.size_out = 0,
 907		.service = NULL,
 908	},
 909	/* New PDSM command descriptors to be added below */
 910
 911	[PAPR_PDSM_HEALTH] = {
 912		.size_in = 0,
 913		.size_out = sizeof(struct nd_papr_pdsm_health),
 914		.service = papr_pdsm_health,
 915	},
 916
 917	[PAPR_PDSM_SMART_INJECT] = {
 918		.size_in = sizeof(struct nd_papr_pdsm_smart_inject),
 919		.size_out = sizeof(struct nd_papr_pdsm_smart_inject),
 920		.service = papr_pdsm_smart_inject,
 921	},
 922	/* Empty */
 923	[PAPR_PDSM_MAX] = {
 924		.size_in = 0,
 925		.size_out = 0,
 926		.service = NULL,
 927	},
 928};
 929
 930/* Given a valid pdsm cmd return its command descriptor else return NULL */
 931static inline const struct pdsm_cmd_desc *pdsm_cmd_desc(enum papr_pdsm cmd)
 932{
 933	if (cmd >= 0 || cmd < ARRAY_SIZE(__pdsm_cmd_descriptors))
 934		return &__pdsm_cmd_descriptors[cmd];
 935
 936	return NULL;
 937}
 938
 939/*
 940 * For a given pdsm request call an appropriate service function.
 941 * Returns errors if any while handling the pdsm command package.
 942 */
 943static int papr_scm_service_pdsm(struct papr_scm_priv *p,
 944				 struct nd_cmd_pkg *pkg)
 945{
 946	/* Get the PDSM header and PDSM command */
 947	struct nd_pkg_pdsm *pdsm_pkg = (struct nd_pkg_pdsm *)pkg->nd_payload;
 948	enum papr_pdsm pdsm = (enum papr_pdsm)pkg->nd_command;
 949	const struct pdsm_cmd_desc *pdsc;
 950	int rc;
 951
 952	/* Fetch corresponding pdsm descriptor for validation and servicing */
 953	pdsc = pdsm_cmd_desc(pdsm);
 954
 955	/* Validate pdsm descriptor */
 956	/* Ensure that reserved fields are 0 */
 957	if (pdsm_pkg->reserved[0] || pdsm_pkg->reserved[1]) {
 958		dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Invalid reserved field\n",
 959			pdsm);
 960		return -EINVAL;
 961	}
 962
 963	/* If pdsm expects some input, then ensure that the size_in matches */
 964	if (pdsc->size_in &&
 965	    pkg->nd_size_in != (pdsc->size_in + ND_PDSM_HDR_SIZE)) {
 966		dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Mismatched size_in=%d\n",
 967			pdsm, pkg->nd_size_in);
 968		return -EINVAL;
 969	}
 970
 971	/* If pdsm wants to return data, then ensure that  size_out matches */
 972	if (pdsc->size_out &&
 973	    pkg->nd_size_out != (pdsc->size_out + ND_PDSM_HDR_SIZE)) {
 974		dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Mismatched size_out=%d\n",
 975			pdsm, pkg->nd_size_out);
 976		return -EINVAL;
 977	}
 978
 979	/* Service the pdsm */
 980	if (pdsc->service) {
 981		dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Servicing..\n", pdsm);
 982
 983		rc = pdsc->service(p, &pdsm_pkg->payload);
 984
 985		if (rc < 0) {
 986			/* error encountered while servicing pdsm */
 987			pdsm_pkg->cmd_status = rc;
 988			pkg->nd_fw_size = ND_PDSM_HDR_SIZE;
 989		} else {
 990			/* pdsm serviced and 'rc' bytes written to payload */
 991			pdsm_pkg->cmd_status = 0;
 992			pkg->nd_fw_size = ND_PDSM_HDR_SIZE + rc;
 993		}
 994	} else {
 995		dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Unsupported PDSM request\n",
 996			pdsm);
 997		pdsm_pkg->cmd_status = -ENOENT;
 998		pkg->nd_fw_size = ND_PDSM_HDR_SIZE;
 999	}
1000
1001	return pdsm_pkg->cmd_status;
1002}
1003
1004static int papr_scm_ndctl(struct nvdimm_bus_descriptor *nd_desc,
1005			  struct nvdimm *nvdimm, unsigned int cmd, void *buf,
1006			  unsigned int buf_len, int *cmd_rc)
1007{
1008	struct nd_cmd_get_config_size *get_size_hdr;
1009	struct nd_cmd_pkg *call_pkg = NULL;
1010	struct papr_scm_priv *p;
1011	int rc;
1012
1013	rc = is_cmd_valid(nvdimm, cmd, buf, buf_len);
1014	if (rc) {
1015		pr_debug("Invalid cmd=0x%x. Err=%d\n", cmd, rc);
1016		return rc;
1017	}
1018
1019	/* Use a local variable in case cmd_rc pointer is NULL */
1020	if (!cmd_rc)
1021		cmd_rc = &rc;
1022
1023	p = nvdimm_provider_data(nvdimm);
1024
1025	switch (cmd) {
1026	case ND_CMD_GET_CONFIG_SIZE:
1027		get_size_hdr = buf;
1028
1029		get_size_hdr->status = 0;
1030		get_size_hdr->max_xfer = 8;
1031		get_size_hdr->config_size = p->metadata_size;
1032		*cmd_rc = 0;
1033		break;
1034
1035	case ND_CMD_GET_CONFIG_DATA:
1036		*cmd_rc = papr_scm_meta_get(p, buf);
1037		break;
1038
1039	case ND_CMD_SET_CONFIG_DATA:
1040		*cmd_rc = papr_scm_meta_set(p, buf);
1041		break;
1042
1043	case ND_CMD_CALL:
1044		call_pkg = (struct nd_cmd_pkg *)buf;
1045		*cmd_rc = papr_scm_service_pdsm(p, call_pkg);
1046		break;
1047
1048	default:
1049		dev_dbg(&p->pdev->dev, "Unknown command = %d\n", cmd);
1050		return -EINVAL;
1051	}
1052
1053	dev_dbg(&p->pdev->dev, "returned with cmd_rc = %d\n", *cmd_rc);
1054
1055	return 0;
1056}
1057
1058static ssize_t health_bitmap_inject_show(struct device *dev,
1059					 struct device_attribute *attr,
1060					 char *buf)
1061{
1062	struct nvdimm *dimm = to_nvdimm(dev);
1063	struct papr_scm_priv *p = nvdimm_provider_data(dimm);
1064
1065	return sprintf(buf, "%#llx\n",
1066		       READ_ONCE(p->health_bitmap_inject_mask));
1067}
1068
1069static DEVICE_ATTR_ADMIN_RO(health_bitmap_inject);
1070
1071static ssize_t perf_stats_show(struct device *dev,
1072			       struct device_attribute *attr, char *buf)
1073{
1074	int index;
1075	ssize_t rc;
1076	struct seq_buf s;
1077	struct papr_scm_perf_stat *stat;
1078	struct papr_scm_perf_stats *stats;
1079	struct nvdimm *dimm = to_nvdimm(dev);
1080	struct papr_scm_priv *p = nvdimm_provider_data(dimm);
1081
1082	if (!p->stat_buffer_len)
1083		return -ENOENT;
1084
1085	/* Allocate the buffer for phyp where stats are written */
1086	stats = kzalloc(p->stat_buffer_len, GFP_KERNEL);
1087	if (!stats)
1088		return -ENOMEM;
1089
1090	/* Ask phyp to return all dimm perf stats */
1091	rc = drc_pmem_query_stats(p, stats, 0);
1092	if (rc)
1093		goto free_stats;
1094	/*
1095	 * Go through the returned output buffer and print stats and
1096	 * values. Since stat_id is essentially a char string of
1097	 * 8 bytes, simply use the string format specifier to print it.
1098	 */
1099	seq_buf_init(&s, buf, PAGE_SIZE);
1100	for (index = 0, stat = stats->scm_statistic;
1101	     index < be32_to_cpu(stats->num_statistics);
1102	     ++index, ++stat) {
1103		seq_buf_printf(&s, "%.8s = 0x%016llX\n",
1104			       stat->stat_id,
1105			       be64_to_cpu(stat->stat_val));
1106	}
1107
1108free_stats:
1109	kfree(stats);
1110	return rc ? rc : (ssize_t)seq_buf_used(&s);
1111}
1112static DEVICE_ATTR_ADMIN_RO(perf_stats);
1113
1114static ssize_t flags_show(struct device *dev,
1115			  struct device_attribute *attr, char *buf)
1116{
1117	struct nvdimm *dimm = to_nvdimm(dev);
1118	struct papr_scm_priv *p = nvdimm_provider_data(dimm);
1119	struct seq_buf s;
1120	u64 health;
1121	int rc;
1122
1123	rc = drc_pmem_query_health(p);
1124	if (rc)
1125		return rc;
1126
1127	/* Copy health_bitmap locally, check masks & update out buffer */
1128	health = READ_ONCE(p->health_bitmap);
1129
1130	seq_buf_init(&s, buf, PAGE_SIZE);
1131	if (health & PAPR_PMEM_UNARMED_MASK)
1132		seq_buf_printf(&s, "not_armed ");
1133
1134	if (health & PAPR_PMEM_BAD_SHUTDOWN_MASK)
1135		seq_buf_printf(&s, "flush_fail ");
1136
1137	if (health & PAPR_PMEM_BAD_RESTORE_MASK)
1138		seq_buf_printf(&s, "restore_fail ");
1139
1140	if (health & PAPR_PMEM_ENCRYPTED)
1141		seq_buf_printf(&s, "encrypted ");
1142
1143	if (health & PAPR_PMEM_SMART_EVENT_MASK)
1144		seq_buf_printf(&s, "smart_notify ");
1145
1146	if (health & PAPR_PMEM_SCRUBBED_AND_LOCKED)
1147		seq_buf_printf(&s, "scrubbed locked ");
1148
1149	if (seq_buf_used(&s))
1150		seq_buf_printf(&s, "\n");
1151
1152	return seq_buf_used(&s);
1153}
1154DEVICE_ATTR_RO(flags);
1155
1156static ssize_t dirty_shutdown_show(struct device *dev,
1157			  struct device_attribute *attr, char *buf)
1158{
1159	struct nvdimm *dimm = to_nvdimm(dev);
1160	struct papr_scm_priv *p = nvdimm_provider_data(dimm);
1161
1162	return sysfs_emit(buf, "%llu\n", p->dirty_shutdown_counter);
1163}
1164DEVICE_ATTR_RO(dirty_shutdown);
1165
1166static umode_t papr_nd_attribute_visible(struct kobject *kobj,
1167					 struct attribute *attr, int n)
1168{
1169	struct device *dev = kobj_to_dev(kobj);
1170	struct nvdimm *nvdimm = to_nvdimm(dev);
1171	struct papr_scm_priv *p = nvdimm_provider_data(nvdimm);
1172
1173	/* For if perf-stats not available remove perf_stats sysfs */
1174	if (attr == &dev_attr_perf_stats.attr && p->stat_buffer_len == 0)
1175		return 0;
1176
1177	return attr->mode;
1178}
1179
1180/* papr_scm specific dimm attributes */
1181static struct attribute *papr_nd_attributes[] = {
1182	&dev_attr_flags.attr,
1183	&dev_attr_perf_stats.attr,
1184	&dev_attr_dirty_shutdown.attr,
1185	&dev_attr_health_bitmap_inject.attr,
1186	NULL,
1187};
1188
1189static const struct attribute_group papr_nd_attribute_group = {
1190	.name = "papr",
1191	.is_visible = papr_nd_attribute_visible,
1192	.attrs = papr_nd_attributes,
1193};
1194
1195static const struct attribute_group *papr_nd_attr_groups[] = {
1196	&papr_nd_attribute_group,
1197	NULL,
1198};
1199
1200static int papr_scm_nvdimm_init(struct papr_scm_priv *p)
1201{
1202	struct device *dev = &p->pdev->dev;
1203	struct nd_mapping_desc mapping;
1204	struct nd_region_desc ndr_desc;
1205	unsigned long dimm_flags;
1206	int target_nid, online_nid;
1207
1208	p->bus_desc.ndctl = papr_scm_ndctl;
1209	p->bus_desc.module = THIS_MODULE;
1210	p->bus_desc.of_node = p->pdev->dev.of_node;
1211	p->bus_desc.provider_name = kstrdup(p->pdev->name, GFP_KERNEL);
1212
1213	/* Set the dimm command family mask to accept PDSMs */
1214	set_bit(NVDIMM_FAMILY_PAPR, &p->bus_desc.dimm_family_mask);
1215
1216	if (!p->bus_desc.provider_name)
1217		return -ENOMEM;
1218
1219	p->bus = nvdimm_bus_register(NULL, &p->bus_desc);
1220	if (!p->bus) {
1221		dev_err(dev, "Error creating nvdimm bus %pOF\n", p->dn);
1222		kfree(p->bus_desc.provider_name);
1223		return -ENXIO;
1224	}
1225
1226	dimm_flags = 0;
1227	set_bit(NDD_LABELING, &dimm_flags);
1228
1229	/*
1230	 * Check if the nvdimm is unarmed. No locking needed as we are still
1231	 * initializing. Ignore error encountered if any.
1232	 */
1233	__drc_pmem_query_health(p);
1234
1235	if (p->health_bitmap & PAPR_PMEM_UNARMED_MASK)
1236		set_bit(NDD_UNARMED, &dimm_flags);
1237
1238	p->nvdimm = nvdimm_create(p->bus, p, papr_nd_attr_groups,
1239				  dimm_flags, PAPR_SCM_DIMM_CMD_MASK, 0, NULL);
1240	if (!p->nvdimm) {
1241		dev_err(dev, "Error creating DIMM object for %pOF\n", p->dn);
1242		goto err;
1243	}
1244
1245	if (nvdimm_bus_check_dimm_count(p->bus, 1))
1246		goto err;
1247
1248	/* now add the region */
1249
1250	memset(&mapping, 0, sizeof(mapping));
1251	mapping.nvdimm = p->nvdimm;
1252	mapping.start = 0;
1253	mapping.size = p->blocks * p->block_size; // XXX: potential overflow?
1254
1255	memset(&ndr_desc, 0, sizeof(ndr_desc));
1256	target_nid = dev_to_node(&p->pdev->dev);
1257	online_nid = numa_map_to_online_node(target_nid);
1258	ndr_desc.numa_node = online_nid;
1259	ndr_desc.target_node = target_nid;
1260	ndr_desc.res = &p->res;
1261	ndr_desc.of_node = p->dn;
1262	ndr_desc.provider_data = p;
1263	ndr_desc.mapping = &mapping;
1264	ndr_desc.num_mappings = 1;
1265	ndr_desc.nd_set = &p->nd_set;
1266
1267	if (p->hcall_flush_required) {
1268		set_bit(ND_REGION_ASYNC, &ndr_desc.flags);
1269		ndr_desc.flush = papr_scm_pmem_flush;
1270	}
1271
1272	if (p->is_volatile)
1273		p->region = nvdimm_volatile_region_create(p->bus, &ndr_desc);
1274	else {
1275		set_bit(ND_REGION_PERSIST_MEMCTRL, &ndr_desc.flags);
1276		p->region = nvdimm_pmem_region_create(p->bus, &ndr_desc);
1277	}
1278	if (!p->region) {
1279		dev_err(dev, "Error registering region %pR from %pOF\n",
1280				ndr_desc.res, p->dn);
1281		goto err;
1282	}
1283	if (target_nid != online_nid)
1284		dev_info(dev, "Region registered with target node %d and online node %d",
1285			 target_nid, online_nid);
1286
1287	mutex_lock(&papr_ndr_lock);
1288	list_add_tail(&p->region_list, &papr_nd_regions);
1289	mutex_unlock(&papr_ndr_lock);
1290
1291	return 0;
1292
1293err:	nvdimm_bus_unregister(p->bus);
1294	kfree(p->bus_desc.provider_name);
1295	return -ENXIO;
1296}
1297
1298static void papr_scm_add_badblock(struct nd_region *region,
1299				  struct nvdimm_bus *bus, u64 phys_addr)
1300{
1301	u64 aligned_addr = ALIGN_DOWN(phys_addr, L1_CACHE_BYTES);
1302
1303	if (nvdimm_bus_add_badrange(bus, aligned_addr, L1_CACHE_BYTES)) {
1304		pr_err("Bad block registration for 0x%llx failed\n", phys_addr);
1305		return;
1306	}
1307
1308	pr_debug("Add memory range (0x%llx - 0x%llx) as bad range\n",
1309		 aligned_addr, aligned_addr + L1_CACHE_BYTES);
1310
1311	nvdimm_region_notify(region, NVDIMM_REVALIDATE_POISON);
1312}
1313
1314static int handle_mce_ue(struct notifier_block *nb, unsigned long val,
1315			 void *data)
1316{
1317	struct machine_check_event *evt = data;
1318	struct papr_scm_priv *p;
1319	u64 phys_addr;
1320	bool found = false;
1321
1322	if (evt->error_type != MCE_ERROR_TYPE_UE)
1323		return NOTIFY_DONE;
1324
1325	if (list_empty(&papr_nd_regions))
1326		return NOTIFY_DONE;
1327
1328	/*
1329	 * The physical address obtained here is PAGE_SIZE aligned, so get the
1330	 * exact address from the effective address
1331	 */
1332	phys_addr = evt->u.ue_error.physical_address +
1333			(evt->u.ue_error.effective_address & ~PAGE_MASK);
1334
1335	if (!evt->u.ue_error.physical_address_provided ||
1336	    !is_zone_device_page(pfn_to_page(phys_addr >> PAGE_SHIFT)))
1337		return NOTIFY_DONE;
1338
1339	/* mce notifier is called from a process context, so mutex is safe */
1340	mutex_lock(&papr_ndr_lock);
1341	list_for_each_entry(p, &papr_nd_regions, region_list) {
1342		if (phys_addr >= p->res.start && phys_addr <= p->res.end) {
1343			found = true;
1344			break;
1345		}
1346	}
1347
1348	if (found)
1349		papr_scm_add_badblock(p->region, p->bus, phys_addr);
1350
1351	mutex_unlock(&papr_ndr_lock);
1352
1353	return found ? NOTIFY_OK : NOTIFY_DONE;
1354}
1355
1356static struct notifier_block mce_ue_nb = {
1357	.notifier_call = handle_mce_ue
1358};
1359
1360static int papr_scm_probe(struct platform_device *pdev)
1361{
1362	struct device_node *dn = pdev->dev.of_node;
1363	u32 drc_index, metadata_size;
1364	u64 blocks, block_size;
1365	struct papr_scm_priv *p;
1366	u8 uuid_raw[UUID_SIZE];
1367	const char *uuid_str;
1368	ssize_t stat_size;
1369	uuid_t uuid;
1370	int rc;
1371
1372	/* check we have all the required DT properties */
1373	if (of_property_read_u32(dn, "ibm,my-drc-index", &drc_index)) {
1374		dev_err(&pdev->dev, "%pOF: missing drc-index!\n", dn);
1375		return -ENODEV;
1376	}
1377
1378	if (of_property_read_u64(dn, "ibm,block-size", &block_size)) {
1379		dev_err(&pdev->dev, "%pOF: missing block-size!\n", dn);
1380		return -ENODEV;
1381	}
1382
1383	if (of_property_read_u64(dn, "ibm,number-of-blocks", &blocks)) {
1384		dev_err(&pdev->dev, "%pOF: missing number-of-blocks!\n", dn);
1385		return -ENODEV;
1386	}
1387
1388	if (of_property_read_string(dn, "ibm,unit-guid", &uuid_str)) {
1389		dev_err(&pdev->dev, "%pOF: missing unit-guid!\n", dn);
1390		return -ENODEV;
1391	}
1392
1393	/*
1394	 * open firmware platform device create won't update the NUMA 
1395	 * distance table. For PAPR SCM devices we use numa_map_to_online_node()
1396	 * to find the nearest online NUMA node and that requires correct
1397	 * distance table information.
1398	 */
1399	update_numa_distance(dn);
1400
1401	p = kzalloc(sizeof(*p), GFP_KERNEL);
1402	if (!p)
1403		return -ENOMEM;
1404
1405	/* Initialize the dimm mutex */
1406	mutex_init(&p->health_mutex);
1407
1408	/* optional DT properties */
1409	of_property_read_u32(dn, "ibm,metadata-size", &metadata_size);
1410
1411	p->dn = dn;
1412	p->drc_index = drc_index;
1413	p->block_size = block_size;
1414	p->blocks = blocks;
1415	p->is_volatile = !of_property_read_bool(dn, "ibm,cache-flush-required");
1416	p->hcall_flush_required = of_property_read_bool(dn, "ibm,hcall-flush-required");
1417
1418	if (of_property_read_u64(dn, "ibm,persistence-failed-count",
1419				 &p->dirty_shutdown_counter))
1420		p->dirty_shutdown_counter = 0;
1421
1422	/* We just need to ensure that set cookies are unique across */
1423	uuid_parse(uuid_str, &uuid);
1424
1425	/*
1426	 * The cookie1 and cookie2 are not really little endian.
1427	 * We store a raw buffer representation of the
1428	 * uuid string so that we can compare this with the label
1429	 * area cookie irrespective of the endian configuration
1430	 * with which the kernel is built.
1431	 *
1432	 * Historically we stored the cookie in the below format.
1433	 * for a uuid string 72511b67-0b3b-42fd-8d1d-5be3cae8bcaa
1434	 *	cookie1 was 0xfd423b0b671b5172
1435	 *	cookie2 was 0xaabce8cae35b1d8d
1436	 */
1437	export_uuid(uuid_raw, &uuid);
1438	p->nd_set.cookie1 = get_unaligned_le64(&uuid_raw[0]);
1439	p->nd_set.cookie2 = get_unaligned_le64(&uuid_raw[8]);
1440
1441	/* might be zero */
1442	p->metadata_size = metadata_size;
1443	p->pdev = pdev;
1444
1445	/* request the hypervisor to bind this region to somewhere in memory */
1446	rc = drc_pmem_bind(p);
1447
1448	/* If phyp says drc memory still bound then force unbound and retry */
1449	if (rc == H_OVERLAP)
1450		rc = drc_pmem_query_n_bind(p);
1451
1452	if (rc != H_SUCCESS) {
1453		dev_err(&p->pdev->dev, "bind err: %d\n", rc);
1454		rc = -ENXIO;
1455		goto err;
1456	}
1457
1458	/* setup the resource for the newly bound range */
1459	p->res.start = p->bound_addr;
1460	p->res.end   = p->bound_addr + p->blocks * p->block_size - 1;
1461	p->res.name  = pdev->name;
1462	p->res.flags = IORESOURCE_MEM;
1463
1464	/* Try retrieving the stat buffer and see if its supported */
1465	stat_size = drc_pmem_query_stats(p, NULL, 0);
1466	if (stat_size > 0) {
1467		p->stat_buffer_len = stat_size;
1468		dev_dbg(&p->pdev->dev, "Max perf-stat size %lu-bytes\n",
1469			p->stat_buffer_len);
1470	}
1471
1472	rc = papr_scm_nvdimm_init(p);
1473	if (rc)
1474		goto err2;
1475
1476	platform_set_drvdata(pdev, p);
1477	papr_scm_pmu_register(p);
1478
1479	return 0;
1480
1481err2:	drc_pmem_unbind(p);
1482err:	kfree(p);
1483	return rc;
1484}
1485
1486static void papr_scm_remove(struct platform_device *pdev)
1487{
1488	struct papr_scm_priv *p = platform_get_drvdata(pdev);
1489
1490	mutex_lock(&papr_ndr_lock);
1491	list_del(&p->region_list);
1492	mutex_unlock(&papr_ndr_lock);
1493
1494	nvdimm_bus_unregister(p->bus);
1495	drc_pmem_unbind(p);
1496
1497	if (pdev->archdata.priv)
1498		unregister_nvdimm_pmu(pdev->archdata.priv);
1499
1500	pdev->archdata.priv = NULL;
1501	kfree(p->bus_desc.provider_name);
1502	kfree(p);
1503}
1504
1505static const struct of_device_id papr_scm_match[] = {
1506	{ .compatible = "ibm,pmemory" },
1507	{ .compatible = "ibm,pmemory-v2" },
1508	{ },
1509};
1510
1511static struct platform_driver papr_scm_driver = {
1512	.probe = papr_scm_probe,
1513	.remove = papr_scm_remove,
1514	.driver = {
1515		.name = "papr_scm",
1516		.of_match_table = papr_scm_match,
1517	},
1518};
1519
1520static int __init papr_scm_init(void)
1521{
1522	int ret;
1523
1524	ret = platform_driver_register(&papr_scm_driver);
1525	if (!ret)
1526		mce_register_notifier(&mce_ue_nb);
1527
1528	return ret;
1529}
1530module_init(papr_scm_init);
1531
1532static void __exit papr_scm_exit(void)
1533{
1534	mce_unregister_notifier(&mce_ue_nb);
1535	platform_driver_unregister(&papr_scm_driver);
1536}
1537module_exit(papr_scm_exit);
1538
1539MODULE_DEVICE_TABLE(of, papr_scm_match);
1540MODULE_DESCRIPTION("PAPR Storage Class Memory interface driver");
1541MODULE_LICENSE("GPL");
1542MODULE_AUTHOR("IBM Corporation");