v4.19.13 snapshot.
diff --git a/drivers/edac/ghes_edac.c b/drivers/edac/ghes_edac.c
new file mode 100644
index 0000000..473aeec
--- /dev/null
+++ b/drivers/edac/ghes_edac.c
@@ -0,0 +1,538 @@
+/*
+ * GHES/EDAC Linux driver
+ *
+ * This file may be distributed under the terms of the GNU General Public
+ * License version 2.
+ *
+ * Copyright (c) 2013 by Mauro Carvalho Chehab
+ *
+ * Red Hat Inc. http://www.redhat.com
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <acpi/ghes.h>
+#include <linux/edac.h>
+#include <linux/dmi.h>
+#include "edac_module.h"
+#include <ras/ras_event.h>
+
+struct ghes_edac_pvt {
+	struct list_head list;
+	struct ghes *ghes;
+	struct mem_ctl_info *mci;
+
+	/* Buffers for the error handling routine */
+	char detail_location[240];
+	char other_detail[160];
+	char msg[80];
+};
+
+static atomic_t ghes_init = ATOMIC_INIT(0);
+static struct ghes_edac_pvt *ghes_pvt;
+
+/*
+ * Sync with other, potentially concurrent callers of
+ * ghes_edac_report_mem_error(). We don't know what the
+ * "inventive" firmware would do.
+ */
+static DEFINE_SPINLOCK(ghes_lock);
+
+/* "ghes_edac.force_load=1" skips the platform check */
+static bool __read_mostly force_load;
+module_param(force_load, bool, 0);
+
+/* Memory Device - Type 17 of SMBIOS spec */
+struct memdev_dmi_entry {
+	u8 type;
+	u8 length;
+	u16 handle;
+	u16 phys_mem_array_handle;
+	u16 mem_err_info_handle;
+	u16 total_width;
+	u16 data_width;
+	u16 size;
+	u8 form_factor;
+	u8 device_set;
+	u8 device_locator;
+	u8 bank_locator;
+	u8 memory_type;
+	u16 type_detail;
+	u16 speed;
+	u8 manufacturer;
+	u8 serial_number;
+	u8 asset_tag;
+	u8 part_number;
+	u8 attributes;
+	u32 extended_size;
+	u16 conf_mem_clk_speed;
+} __attribute__((__packed__));
+
+struct ghes_edac_dimm_fill {
+	struct mem_ctl_info *mci;
+	unsigned count;
+};
+
+static void ghes_edac_count_dimms(const struct dmi_header *dh, void *arg)
+{
+	int *num_dimm = arg;
+
+	if (dh->type == DMI_ENTRY_MEM_DEVICE)
+		(*num_dimm)++;
+}
+
+static void ghes_edac_dmidecode(const struct dmi_header *dh, void *arg)
+{
+	struct ghes_edac_dimm_fill *dimm_fill = arg;
+	struct mem_ctl_info *mci = dimm_fill->mci;
+
+	if (dh->type == DMI_ENTRY_MEM_DEVICE) {
+		struct memdev_dmi_entry *entry = (struct memdev_dmi_entry *)dh;
+		struct dimm_info *dimm = EDAC_DIMM_PTR(mci->layers, mci->dimms,
+						       mci->n_layers,
+						       dimm_fill->count, 0, 0);
+		u16 rdr_mask = BIT(7) | BIT(13);
+
+		if (entry->size == 0xffff) {
+			pr_info("Can't get DIMM%i size\n",
+				dimm_fill->count);
+			dimm->nr_pages = MiB_TO_PAGES(32);/* Unknown */
+		} else if (entry->size == 0x7fff) {
+			dimm->nr_pages = MiB_TO_PAGES(entry->extended_size);
+		} else {
+			if (entry->size & BIT(15))
+				dimm->nr_pages = MiB_TO_PAGES((entry->size & 0x7fff) << 10);
+			else
+				dimm->nr_pages = MiB_TO_PAGES(entry->size);
+		}
+
+		switch (entry->memory_type) {
+		case 0x12:
+			if (entry->type_detail & BIT(13))
+				dimm->mtype = MEM_RDDR;
+			else
+				dimm->mtype = MEM_DDR;
+			break;
+		case 0x13:
+			if (entry->type_detail & BIT(13))
+				dimm->mtype = MEM_RDDR2;
+			else
+				dimm->mtype = MEM_DDR2;
+			break;
+		case 0x14:
+			dimm->mtype = MEM_FB_DDR2;
+			break;
+		case 0x18:
+			if (entry->type_detail & BIT(12))
+				dimm->mtype = MEM_NVDIMM;
+			else if (entry->type_detail & BIT(13))
+				dimm->mtype = MEM_RDDR3;
+			else
+				dimm->mtype = MEM_DDR3;
+			break;
+		case 0x1a:
+			if (entry->type_detail & BIT(12))
+				dimm->mtype = MEM_NVDIMM;
+			else if (entry->type_detail & BIT(13))
+				dimm->mtype = MEM_RDDR4;
+			else
+				dimm->mtype = MEM_DDR4;
+			break;
+		default:
+			if (entry->type_detail & BIT(6))
+				dimm->mtype = MEM_RMBS;
+			else if ((entry->type_detail & rdr_mask) == rdr_mask)
+				dimm->mtype = MEM_RDR;
+			else if (entry->type_detail & BIT(7))
+				dimm->mtype = MEM_SDR;
+			else if (entry->type_detail & BIT(9))
+				dimm->mtype = MEM_EDO;
+			else
+				dimm->mtype = MEM_UNKNOWN;
+		}
+
+		/*
+		 * Actually, we can only detect if the memory has bits for
+		 * checksum or not
+		 */
+		if (entry->total_width == entry->data_width)
+			dimm->edac_mode = EDAC_NONE;
+		else
+			dimm->edac_mode = EDAC_SECDED;
+
+		dimm->dtype = DEV_UNKNOWN;
+		dimm->grain = 128;		/* Likely, worse case */
+
+		/*
+		 * FIXME: It shouldn't be hard to also fill the DIMM labels
+		 */
+
+		if (dimm->nr_pages) {
+			edac_dbg(1, "DIMM%i: %s size = %d MB%s\n",
+				dimm_fill->count, edac_mem_types[dimm->mtype],
+				PAGES_TO_MiB(dimm->nr_pages),
+				(dimm->edac_mode != EDAC_NONE) ? "(ECC)" : "");
+			edac_dbg(2, "\ttype %d, detail 0x%02x, width %d(total %d)\n",
+				entry->memory_type, entry->type_detail,
+				entry->total_width, entry->data_width);
+		}
+
+		dimm_fill->count++;
+	}
+}
+
+void ghes_edac_report_mem_error(int sev, struct cper_sec_mem_err *mem_err)
+{
+	enum hw_event_mc_err_type type;
+	struct edac_raw_error_desc *e;
+	struct mem_ctl_info *mci;
+	struct ghes_edac_pvt *pvt = ghes_pvt;
+	unsigned long flags;
+	char *p;
+	u8 grain_bits;
+
+	if (!pvt)
+		return;
+
+	/*
+	 * We can do the locking below because GHES defers error processing
+	 * from NMI to IRQ context. Whenever that changes, we'd at least
+	 * know.
+	 */
+	if (WARN_ON_ONCE(in_nmi()))
+		return;
+
+	spin_lock_irqsave(&ghes_lock, flags);
+
+	mci = pvt->mci;
+	e = &mci->error_desc;
+
+	/* Cleans the error report buffer */
+	memset(e, 0, sizeof (*e));
+	e->error_count = 1;
+	strcpy(e->label, "unknown label");
+	e->msg = pvt->msg;
+	e->other_detail = pvt->other_detail;
+	e->top_layer = -1;
+	e->mid_layer = -1;
+	e->low_layer = -1;
+	*pvt->other_detail = '\0';
+	*pvt->msg = '\0';
+
+	switch (sev) {
+	case GHES_SEV_CORRECTED:
+		type = HW_EVENT_ERR_CORRECTED;
+		break;
+	case GHES_SEV_RECOVERABLE:
+		type = HW_EVENT_ERR_UNCORRECTED;
+		break;
+	case GHES_SEV_PANIC:
+		type = HW_EVENT_ERR_FATAL;
+		break;
+	default:
+	case GHES_SEV_NO:
+		type = HW_EVENT_ERR_INFO;
+	}
+
+	edac_dbg(1, "error validation_bits: 0x%08llx\n",
+		 (long long)mem_err->validation_bits);
+
+	/* Error type, mapped on e->msg */
+	if (mem_err->validation_bits & CPER_MEM_VALID_ERROR_TYPE) {
+		p = pvt->msg;
+		switch (mem_err->error_type) {
+		case 0:
+			p += sprintf(p, "Unknown");
+			break;
+		case 1:
+			p += sprintf(p, "No error");
+			break;
+		case 2:
+			p += sprintf(p, "Single-bit ECC");
+			break;
+		case 3:
+			p += sprintf(p, "Multi-bit ECC");
+			break;
+		case 4:
+			p += sprintf(p, "Single-symbol ChipKill ECC");
+			break;
+		case 5:
+			p += sprintf(p, "Multi-symbol ChipKill ECC");
+			break;
+		case 6:
+			p += sprintf(p, "Master abort");
+			break;
+		case 7:
+			p += sprintf(p, "Target abort");
+			break;
+		case 8:
+			p += sprintf(p, "Parity Error");
+			break;
+		case 9:
+			p += sprintf(p, "Watchdog timeout");
+			break;
+		case 10:
+			p += sprintf(p, "Invalid address");
+			break;
+		case 11:
+			p += sprintf(p, "Mirror Broken");
+			break;
+		case 12:
+			p += sprintf(p, "Memory Sparing");
+			break;
+		case 13:
+			p += sprintf(p, "Scrub corrected error");
+			break;
+		case 14:
+			p += sprintf(p, "Scrub uncorrected error");
+			break;
+		case 15:
+			p += sprintf(p, "Physical Memory Map-out event");
+			break;
+		default:
+			p += sprintf(p, "reserved error (%d)",
+				     mem_err->error_type);
+		}
+	} else {
+		strcpy(pvt->msg, "unknown error");
+	}
+
+	/* Error address */
+	if (mem_err->validation_bits & CPER_MEM_VALID_PA) {
+		e->page_frame_number = mem_err->physical_addr >> PAGE_SHIFT;
+		e->offset_in_page = mem_err->physical_addr & ~PAGE_MASK;
+	}
+
+	/* Error grain */
+	if (mem_err->validation_bits & CPER_MEM_VALID_PA_MASK)
+		e->grain = ~(mem_err->physical_addr_mask & ~PAGE_MASK);
+
+	/* Memory error location, mapped on e->location */
+	p = e->location;
+	if (mem_err->validation_bits & CPER_MEM_VALID_NODE)
+		p += sprintf(p, "node:%d ", mem_err->node);
+	if (mem_err->validation_bits & CPER_MEM_VALID_CARD)
+		p += sprintf(p, "card:%d ", mem_err->card);
+	if (mem_err->validation_bits & CPER_MEM_VALID_MODULE)
+		p += sprintf(p, "module:%d ", mem_err->module);
+	if (mem_err->validation_bits & CPER_MEM_VALID_RANK_NUMBER)
+		p += sprintf(p, "rank:%d ", mem_err->rank);
+	if (mem_err->validation_bits & CPER_MEM_VALID_BANK)
+		p += sprintf(p, "bank:%d ", mem_err->bank);
+	if (mem_err->validation_bits & CPER_MEM_VALID_ROW)
+		p += sprintf(p, "row:%d ", mem_err->row);
+	if (mem_err->validation_bits & CPER_MEM_VALID_COLUMN)
+		p += sprintf(p, "col:%d ", mem_err->column);
+	if (mem_err->validation_bits & CPER_MEM_VALID_BIT_POSITION)
+		p += sprintf(p, "bit_pos:%d ", mem_err->bit_pos);
+	if (mem_err->validation_bits & CPER_MEM_VALID_MODULE_HANDLE) {
+		const char *bank = NULL, *device = NULL;
+		dmi_memdev_name(mem_err->mem_dev_handle, &bank, &device);
+		if (bank != NULL && device != NULL)
+			p += sprintf(p, "DIMM location:%s %s ", bank, device);
+		else
+			p += sprintf(p, "DIMM DMI handle: 0x%.4x ",
+				     mem_err->mem_dev_handle);
+	}
+	if (p > e->location)
+		*(p - 1) = '\0';
+
+	/* All other fields are mapped on e->other_detail */
+	p = pvt->other_detail;
+	if (mem_err->validation_bits & CPER_MEM_VALID_ERROR_STATUS) {
+		u64 status = mem_err->error_status;
+
+		p += sprintf(p, "status(0x%016llx): ", (long long)status);
+		switch ((status >> 8) & 0xff) {
+		case 1:
+			p += sprintf(p, "Error detected internal to the component ");
+			break;
+		case 16:
+			p += sprintf(p, "Error detected in the bus ");
+			break;
+		case 4:
+			p += sprintf(p, "Storage error in DRAM memory ");
+			break;
+		case 5:
+			p += sprintf(p, "Storage error in TLB ");
+			break;
+		case 6:
+			p += sprintf(p, "Storage error in cache ");
+			break;
+		case 7:
+			p += sprintf(p, "Error in one or more functional units ");
+			break;
+		case 8:
+			p += sprintf(p, "component failed self test ");
+			break;
+		case 9:
+			p += sprintf(p, "Overflow or undervalue of internal queue ");
+			break;
+		case 17:
+			p += sprintf(p, "Virtual address not found on IO-TLB or IO-PDIR ");
+			break;
+		case 18:
+			p += sprintf(p, "Improper access error ");
+			break;
+		case 19:
+			p += sprintf(p, "Access to a memory address which is not mapped to any component ");
+			break;
+		case 20:
+			p += sprintf(p, "Loss of Lockstep ");
+			break;
+		case 21:
+			p += sprintf(p, "Response not associated with a request ");
+			break;
+		case 22:
+			p += sprintf(p, "Bus parity error - must also set the A, C, or D Bits ");
+			break;
+		case 23:
+			p += sprintf(p, "Detection of a PATH_ERROR ");
+			break;
+		case 25:
+			p += sprintf(p, "Bus operation timeout ");
+			break;
+		case 26:
+			p += sprintf(p, "A read was issued to data that has been poisoned ");
+			break;
+		default:
+			p += sprintf(p, "reserved ");
+			break;
+		}
+	}
+	if (mem_err->validation_bits & CPER_MEM_VALID_REQUESTOR_ID)
+		p += sprintf(p, "requestorID: 0x%016llx ",
+			     (long long)mem_err->requestor_id);
+	if (mem_err->validation_bits & CPER_MEM_VALID_RESPONDER_ID)
+		p += sprintf(p, "responderID: 0x%016llx ",
+			     (long long)mem_err->responder_id);
+	if (mem_err->validation_bits & CPER_MEM_VALID_TARGET_ID)
+		p += sprintf(p, "targetID: 0x%016llx ",
+			     (long long)mem_err->responder_id);
+	if (p > pvt->other_detail)
+		*(p - 1) = '\0';
+
+	/* Generate the trace event */
+	grain_bits = fls_long(e->grain);
+	snprintf(pvt->detail_location, sizeof(pvt->detail_location),
+		 "APEI location: %s %s", e->location, e->other_detail);
+	trace_mc_event(type, e->msg, e->label, e->error_count,
+		       mci->mc_idx, e->top_layer, e->mid_layer, e->low_layer,
+		       (e->page_frame_number << PAGE_SHIFT) | e->offset_in_page,
+		       grain_bits, e->syndrome, pvt->detail_location);
+
+	edac_raw_mc_handle_error(type, mci, e);
+	spin_unlock_irqrestore(&ghes_lock, flags);
+}
+
+/*
+ * Known systems that are safe to enable this module.
+ */
+static struct acpi_platform_list plat_list[] = {
+	{"HPE   ", "Server  ", 0, ACPI_SIG_FADT, all_versions},
+	{ } /* End */
+};
+
+int ghes_edac_register(struct ghes *ghes, struct device *dev)
+{
+	bool fake = false;
+	int rc, num_dimm = 0;
+	struct mem_ctl_info *mci;
+	struct edac_mc_layer layers[1];
+	struct ghes_edac_dimm_fill dimm_fill;
+	int idx = -1;
+
+	if (IS_ENABLED(CONFIG_X86)) {
+		/* Check if safe to enable on this system */
+		idx = acpi_match_platform_list(plat_list);
+		if (!force_load && idx < 0)
+			return -ENODEV;
+	} else {
+		idx = 0;
+	}
+
+	/*
+	 * We have only one logical memory controller to which all DIMMs belong.
+	 */
+	if (atomic_inc_return(&ghes_init) > 1)
+		return 0;
+
+	/* Get the number of DIMMs */
+	dmi_walk(ghes_edac_count_dimms, &num_dimm);
+
+	/* Check if we've got a bogus BIOS */
+	if (num_dimm == 0) {
+		fake = true;
+		num_dimm = 1;
+	}
+
+	layers[0].type = EDAC_MC_LAYER_ALL_MEM;
+	layers[0].size = num_dimm;
+	layers[0].is_virt_csrow = true;
+
+	mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers, sizeof(struct ghes_edac_pvt));
+	if (!mci) {
+		pr_info("Can't allocate memory for EDAC data\n");
+		return -ENOMEM;
+	}
+
+	ghes_pvt	= mci->pvt_info;
+	ghes_pvt->ghes	= ghes;
+	ghes_pvt->mci	= mci;
+
+	mci->pdev = dev;
+	mci->mtype_cap = MEM_FLAG_EMPTY;
+	mci->edac_ctl_cap = EDAC_FLAG_NONE;
+	mci->edac_cap = EDAC_FLAG_NONE;
+	mci->mod_name = "ghes_edac.c";
+	mci->ctl_name = "ghes_edac";
+	mci->dev_name = "ghes";
+
+	if (fake) {
+		pr_info("This system has a very crappy BIOS: It doesn't even list the DIMMS.\n");
+		pr_info("Its SMBIOS info is wrong. It is doubtful that the error report would\n");
+		pr_info("work on such system. Use this driver with caution\n");
+	} else if (idx < 0) {
+		pr_info("This EDAC driver relies on BIOS to enumerate memory and get error reports.\n");
+		pr_info("Unfortunately, not all BIOSes reflect the memory layout correctly.\n");
+		pr_info("So, the end result of using this driver varies from vendor to vendor.\n");
+		pr_info("If you find incorrect reports, please contact your hardware vendor\n");
+		pr_info("to correct its BIOS.\n");
+		pr_info("This system has %d DIMM sockets.\n", num_dimm);
+	}
+
+	if (!fake) {
+		dimm_fill.count = 0;
+		dimm_fill.mci = mci;
+		dmi_walk(ghes_edac_dmidecode, &dimm_fill);
+	} else {
+		struct dimm_info *dimm = EDAC_DIMM_PTR(mci->layers, mci->dimms,
+						       mci->n_layers, 0, 0, 0);
+
+		dimm->nr_pages = 1;
+		dimm->grain = 128;
+		dimm->mtype = MEM_UNKNOWN;
+		dimm->dtype = DEV_UNKNOWN;
+		dimm->edac_mode = EDAC_SECDED;
+	}
+
+	rc = edac_mc_add_mc(mci);
+	if (rc < 0) {
+		pr_info("Can't register at EDAC core\n");
+		edac_mc_free(mci);
+		return -ENODEV;
+	}
+	return 0;
+}
+
+void ghes_edac_unregister(struct ghes *ghes)
+{
+	struct mem_ctl_info *mci;
+
+	if (!ghes_pvt)
+		return;
+
+	mci = ghes_pvt->mci;
+	edac_mc_del_mc(mci->pdev);
+	edac_mc_free(mci);
+}