1 files changed, 295 insertions, 1 deletions

diff --git a/arch/powerpc/platforms/pseries/papr_scm.c b/arch/powerpc/platforms/pseries/papr_scm.c
index 9c569078a09f..f439f0dfea7d 100644
--- a/arch/powerpc/platforms/pseries/papr_scm.c
+++ b/arch/powerpc/platforms/pseries/papr_scm.c
@@ -13,9 +13,11 @@
 #include <linux/platform_device.h>
 #include <linux/delay.h>
 #include <linux/seq_buf.h>
+#include <linux/nd.h>
 
 #include <asm/plpar_wrappers.h>
 #include <asm/papr_pdsm.h>
+#include <asm/mce.h>
 
 #define BIND_ANY_ADDR (~0ul)
 
@@ -62,6 +64,26 @@
 				    PAPR_PMEM_HEALTH_FATAL |	\
 				    PAPR_PMEM_HEALTH_UNHEALTHY)
 
+#define PAPR_SCM_PERF_STATS_EYECATCHER __stringify(SCMSTATS)
+#define PAPR_SCM_PERF_STATS_VERSION 0x1
+
+/* Struct holding a single performance metric */
+struct papr_scm_perf_stat {
+	u8 stat_id[8];
+	__be64 stat_val;
+} __packed;
+
+/* Struct exchanged between kernel and PHYP for fetching drc perf stats */
+struct papr_scm_perf_stats {
+	u8 eye_catcher[8];
+	/* Should be PAPR_SCM_PERF_STATS_VERSION */
+	__be32 stats_version;
+	/* Number of stats following */
+	__be32 num_statistics;
+	/* zero or more performance matrics */
+	struct papr_scm_perf_stat scm_statistic[];
+} __packed;
+
 /* private struct associated with each region */
 struct papr_scm_priv {
 	struct platform_device *pdev;
@@ -80,6 +102,7 @@ struct papr_scm_priv {
 	struct resource res;
 	struct nd_region *region;
 	struct nd_interleave_set nd_set;
+	struct list_head region_list;
 
 	/* Protect dimm health data from concurrent read/writes */
 	struct mutex health_mutex;
@@ -89,8 +112,14 @@ struct papr_scm_priv {
 
 	/* Health information for the dimm */
 	u64 health_bitmap;
+
+	/* length of the stat buffer as expected by phyp */
+	size_t stat_buffer_len;
 };
 
+static LIST_HEAD(papr_nd_regions);
+static DEFINE_MUTEX(papr_ndr_lock);
+
 static int drc_pmem_bind(struct papr_scm_priv *p)
 {
 	unsigned long ret[PLPAR_HCALL_BUFSIZE];
@@ -195,6 +224,79 @@ err_out:
 }
 
 /*
+ * Query the Dimm performance stats from PHYP and copy them (if returned) to
+ * provided struct papr_scm_perf_stats instance 'stats' that can hold atleast
+ * (num_stats + header) bytes.
+ * - If buff_stats == NULL the return value is the size in byes of the buffer
+ * needed to hold all supported performance-statistics.
+ * - If buff_stats != NULL and num_stats == 0 then we copy all known
+ * performance-statistics to 'buff_stat' and expect to be large enough to
+ * hold them.
+ * - if buff_stats != NULL and num_stats > 0 then copy the requested
+ * performance-statistics to buff_stats.
+ */
+static ssize_t drc_pmem_query_stats(struct papr_scm_priv *p,
+				    struct papr_scm_perf_stats *buff_stats,
+				    unsigned int num_stats)
+{
+	unsigned long ret[PLPAR_HCALL_BUFSIZE];
+	size_t size;
+	s64 rc;
+
+	/* Setup the out buffer */
+	if (buff_stats) {
+		memcpy(buff_stats->eye_catcher,
+		       PAPR_SCM_PERF_STATS_EYECATCHER, 8);
+		buff_stats->stats_version =
+			cpu_to_be32(PAPR_SCM_PERF_STATS_VERSION);
+		buff_stats->num_statistics =
+			cpu_to_be32(num_stats);
+
+		/*
+		 * Calculate the buffer size based on num-stats provided
+		 * or use the prefetched max buffer length
+		 */
+		if (num_stats)
+			/* Calculate size from the num_stats */
+			size = sizeof(struct papr_scm_perf_stats) +
+				num_stats * sizeof(struct papr_scm_perf_stat);
+		else
+			size = p->stat_buffer_len;
+	} else {
+		/* In case of no out buffer ignore the size */
+		size = 0;
+	}
+
+	/* Do the HCALL asking PHYP for info */
+	rc = plpar_hcall(H_SCM_PERFORMANCE_STATS, ret, p->drc_index,
+			 buff_stats ? virt_to_phys(buff_stats) : 0,
+			 size);
+
+	/* Check if the error was due to an unknown stat-id */
+	if (rc == H_PARTIAL) {
+		dev_err(&p->pdev->dev,
+			"Unknown performance stats, Err:0x%016lX\n", ret[0]);
+		return -ENOENT;
+	} else if (rc != H_SUCCESS) {
+		dev_err(&p->pdev->dev,
+			"Failed to query performance stats, Err:%lld\n", rc);
+		return -EIO;
+
+	} else if (!size) {
+		/* Handle case where stat buffer size was requested */
+		dev_dbg(&p->pdev->dev,
+			"Performance stats size %ld\n", ret[0]);
+		return ret[0];
+	}
+
+	/* Successfully fetched the requested stats from phyp */
+	dev_dbg(&p->pdev->dev,
+		"Performance stats returned %d stats\n",
+		be32_to_cpu(buff_stats->num_statistics));
+	return 0;
+}
+
+/*
  * Issue hcall to retrieve dimm health info and populate papr_scm_priv with the
  * health information.
  */
@@ -416,6 +518,51 @@ static int is_cmd_valid(struct nvdimm *nvdimm, unsigned int cmd, void *buf,
 	return 0;
 }
 
+static int papr_pdsm_fuel_gauge(struct papr_scm_priv *p,
+				union nd_pdsm_payload *payload)
+{
+	int rc, size;
+	u64 statval;
+	struct papr_scm_perf_stat *stat;
+	struct papr_scm_perf_stats *stats;
+
+	/* Silently fail if fetching performance metrics isn't  supported */
+	if (!p->stat_buffer_len)
+		return 0;
+
+	/* Allocate request buffer enough to hold single performance stat */
+	size = sizeof(struct papr_scm_perf_stats) +
+		sizeof(struct papr_scm_perf_stat);
+
+	stats = kzalloc(size, GFP_KERNEL);
+	if (!stats)
+		return -ENOMEM;
+
+	stat = &stats->scm_statistic[0];
+	memcpy(&stat->stat_id, "MemLife ", sizeof(stat->stat_id));
+	stat->stat_val = 0;
+
+	/* Fetch the fuel gauge and populate it in payload */
+	rc = drc_pmem_query_stats(p, stats, 1);
+	if (rc < 0) {
+		dev_dbg(&p->pdev->dev, "Err(%d) fetching fuel gauge\n", rc);
+		goto free_stats;
+	}
+
+	statval = be64_to_cpu(stat->stat_val);
+	dev_dbg(&p->pdev->dev,
+		"Fetched fuel-gauge %llu", statval);
+	payload->health.extension_flags |=
+		PDSM_DIMM_HEALTH_RUN_GAUGE_VALID;
+	payload->health.dimm_fuel_gauge = statval;
+
+	rc = sizeof(struct nd_papr_pdsm_health);
+
+free_stats:
+	kfree(stats);
+	return rc;
+}
+
 /* Fetch the DIMM health info and populate it in provided package. */
 static int papr_pdsm_health(struct papr_scm_priv *p,
 			    union nd_pdsm_payload *payload)
@@ -456,6 +603,10 @@ static int papr_pdsm_health(struct papr_scm_priv *p,
 
 	/* struct populated hence can release the mutex now */
 	mutex_unlock(&p->health_mutex);
+
+	/* Populate the fuel gauge meter in the payload */
+	papr_pdsm_fuel_gauge(p, payload);
+
 	rc = sizeof(struct nd_papr_pdsm_health);
 
 out:
@@ -631,6 +782,48 @@ static int papr_scm_ndctl(struct nvdimm_bus_descriptor *nd_desc,
 	return 0;
 }
 
+static ssize_t perf_stats_show(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	int index, rc;
+	struct seq_buf s;
+	struct papr_scm_perf_stat *stat;
+	struct papr_scm_perf_stats *stats;
+	struct nvdimm *dimm = to_nvdimm(dev);
+	struct papr_scm_priv *p = nvdimm_provider_data(dimm);
+
+	if (!p->stat_buffer_len)
+		return -ENOENT;
+
+	/* Allocate the buffer for phyp where stats are written */
+	stats = kzalloc(p->stat_buffer_len, GFP_KERNEL);
+	if (!stats)
+		return -ENOMEM;
+
+	/* Ask phyp to return all dimm perf stats */
+	rc = drc_pmem_query_stats(p, stats, 0);
+	if (rc)
+		goto free_stats;
+	/*
+	 * Go through the returned output buffer and print stats and
+	 * values. Since stat_id is essentially a char string of
+	 * 8 bytes, simply use the string format specifier to print it.
+	 */
+	seq_buf_init(&s, buf, PAGE_SIZE);
+	for (index = 0, stat = stats->scm_statistic;
+	     index < be32_to_cpu(stats->num_statistics);
+	     ++index, ++stat) {
+		seq_buf_printf(&s, "%.8s = 0x%016llX\n",
+			       stat->stat_id,
+			       be64_to_cpu(stat->stat_val));
+	}
+
+free_stats:
+	kfree(stats);
+	return rc ? rc : seq_buf_used(&s);
+}
+DEVICE_ATTR_RO(perf_stats);
+
 static ssize_t flags_show(struct device *dev,
 			  struct device_attribute *attr, char *buf)
 {
@@ -676,6 +869,7 @@ DEVICE_ATTR_RO(flags);
 /* papr_scm specific dimm attributes */
 static struct attribute *papr_nd_attributes[] = {
 	&dev_attr_flags.attr,
+	&dev_attr_perf_stats.attr,
 	NULL,
 };
 
@@ -696,6 +890,7 @@ static int papr_scm_nvdimm_init(struct papr_scm_priv *p)
 	struct nd_region_desc ndr_desc;
 	unsigned long dimm_flags;
 	int target_nid, online_nid;
+	ssize_t stat_size;
 
 	p->bus_desc.ndctl = papr_scm_ndctl;
 	p->bus_desc.module = THIS_MODULE;
@@ -759,6 +954,20 @@ static int papr_scm_nvdimm_init(struct papr_scm_priv *p)
 		dev_info(dev, "Region registered with target node %d and online node %d",
 			 target_nid, online_nid);
 
+	mutex_lock(&papr_ndr_lock);
+	list_add_tail(&p->region_list, &papr_nd_regions);
+	mutex_unlock(&papr_ndr_lock);
+
+	/* Try retriving the stat buffer and see if its supported */
+	stat_size = drc_pmem_query_stats(p, NULL, 0);
+	if (stat_size > 0) {
+		p->stat_buffer_len = stat_size;
+		dev_dbg(&p->pdev->dev, "Max perf-stat size %lu-bytes\n",
+			p->stat_buffer_len);
+	} else {
+		dev_info(&p->pdev->dev, "Dimm performance stats unavailable\n");
+	}
+
 	return 0;
 
 err:	nvdimm_bus_unregister(p->bus);
@@ -766,6 +975,68 @@ err:	nvdimm_bus_unregister(p->bus);
 	return -ENXIO;
 }
 
+static void papr_scm_add_badblock(struct nd_region *region,
+				  struct nvdimm_bus *bus, u64 phys_addr)
+{
+	u64 aligned_addr = ALIGN_DOWN(phys_addr, L1_CACHE_BYTES);
+
+	if (nvdimm_bus_add_badrange(bus, aligned_addr, L1_CACHE_BYTES)) {
+		pr_err("Bad block registration for 0x%llx failed\n", phys_addr);
+		return;
+	}
+
+	pr_debug("Add memory range (0x%llx - 0x%llx) as bad range\n",
+		 aligned_addr, aligned_addr + L1_CACHE_BYTES);
+
+	nvdimm_region_notify(region, NVDIMM_REVALIDATE_POISON);
+}
+
+static int handle_mce_ue(struct notifier_block *nb, unsigned long val,
+			 void *data)
+{
+	struct machine_check_event *evt = data;
+	struct papr_scm_priv *p;
+	u64 phys_addr;
+	bool found = false;
+
+	if (evt->error_type != MCE_ERROR_TYPE_UE)
+		return NOTIFY_DONE;
+
+	if (list_empty(&papr_nd_regions))
+		return NOTIFY_DONE;
+
+	/*
+	 * The physical address obtained here is PAGE_SIZE aligned, so get the
+	 * exact address from the effective address
+	 */
+	phys_addr = evt->u.ue_error.physical_address +
+			(evt->u.ue_error.effective_address & ~PAGE_MASK);
+
+	if (!evt->u.ue_error.physical_address_provided ||
+	    !is_zone_device_page(pfn_to_page(phys_addr >> PAGE_SHIFT)))
+		return NOTIFY_DONE;
+
+	/* mce notifier is called from a process context, so mutex is safe */
+	mutex_lock(&papr_ndr_lock);
+	list_for_each_entry(p, &papr_nd_regions, region_list) {
+		if (phys_addr >= p->res.start && phys_addr <= p->res.end) {
+			found = true;
+			break;
+		}
+	}
+
+	if (found)
+		papr_scm_add_badblock(p->region, p->bus, phys_addr);
+
+	mutex_unlock(&papr_ndr_lock);
+
+	return found ? NOTIFY_OK : NOTIFY_DONE;
+}
+
+static struct notifier_block mce_ue_nb = {
+	.notifier_call = handle_mce_ue
+};
+
 static int papr_scm_probe(struct platform_device *pdev)
 {
 	struct device_node *dn = pdev->dev.of_node;
@@ -866,6 +1137,10 @@ static int papr_scm_remove(struct platform_device *pdev)
 {
 	struct papr_scm_priv *p = platform_get_drvdata(pdev);
 
+	mutex_lock(&papr_ndr_lock);
+	list_del(&p->region_list);
+	mutex_unlock(&papr_ndr_lock);
+
 	nvdimm_bus_unregister(p->bus);
 	drc_pmem_unbind(p);
 	kfree(p->bus_desc.provider_name);
@@ -876,6 +1151,7 @@ static int papr_scm_remove(struct platform_device *pdev)
 
 static const struct of_device_id papr_scm_match[] = {
 	{ .compatible = "ibm,pmemory" },
+	{ .compatible = "ibm,pmemory-v2" },
 	{ },
 };
 
@@ -888,7 +1164,25 @@ static struct platform_driver papr_scm_driver = {
 	},
 };
 
-module_platform_driver(papr_scm_driver);
+static int __init papr_scm_init(void)
+{
+	int ret;
+
+	ret = platform_driver_register(&papr_scm_driver);
+	if (!ret)
+		mce_register_notifier(&mce_ue_nb);
+
+	return ret;
+}
+module_init(papr_scm_init);
+
+static void __exit papr_scm_exit(void)
+{
+	mce_unregister_notifier(&mce_ue_nb);
+	platform_driver_unregister(&papr_scm_driver);
+}
+module_exit(papr_scm_exit);
+
 MODULE_DEVICE_TABLE(of, papr_scm_match);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("IBM Corporation");