From: Tony Luck <tony.luck@intel.com>
Date: Mon, 12 Mar 2018 11:24:30 -0700
Subject: EDAC, skx_edac: Detect non-volatile DIMMs
Patch-mainline: v4.17-rc1
Git-commit: 58ca9ac1463d07d24b9fa8befe065192abca6f76
References: bsc#1099125, fate#326228

This just covers the topology function of the EDAC driver. We locate
which DIMM slots are populated with NVDIMMs and query the NFIT and
SMBIOS tables to get the size.

Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Aristeu Rozanski <aris@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: linux-acpi@vger.kernel.org
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: linux-nvdimm@lists.01.org
Link: http://lkml.kernel.org/r/20180312182430.10335-6-tony.luck@intel.com
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Johannes Thumshirn <jthumshirn@suse.de>
---
 drivers/edac/Kconfig    |    5 +++
 drivers/edac/skx_edac.c |   64 ++++++++++++++++++++++++++++++++++++++++++++----
 2 files changed, 63 insertions(+), 6 deletions(-)

--- a/drivers/edac/Kconfig
+++ b/drivers/edac/Kconfig
@@ -232,9 +232,12 @@ config EDAC_SBRIDGE
 config EDAC_SKX
 	tristate "Intel Skylake server Integrated MC"
 	depends on PCI && X86_64 && X86_MCE_INTEL && PCI_MMCONFIG
+	select DMI
 	help
 	  Support for error detection and correction the Intel
-	  Skylake server Integrated Memory Controllers.
+	  Skylake server Integrated Memory Controllers. If your
+	  system has non-volatile DIMMs you should also manually
+	  select CONFIG_ACPI_NFIT.
 
 config EDAC_PND2
 	tristate "Intel Pondicherry2"
--- a/drivers/edac/skx_edac.c
+++ b/drivers/edac/skx_edac.c
@@ -14,6 +14,8 @@
 
 #include <linux/module.h>
 #include <linux/init.h>
+#include <linux/acpi.h>
+#include <linux/dmi.h>
 #include <linux/pci.h>
 #include <linux/pci_ids.h>
 #include <linux/slab.h>
@@ -24,6 +26,7 @@
 #include <linux/bitmap.h>
 #include <linux/math64.h>
 #include <linux/mod_devicetable.h>
+#include <acpi/nfit.h>
 #include <asm/cpu_device_id.h>
 #include <asm/intel-family.h>
 #include <asm/processor.h>
@@ -304,6 +307,7 @@ static int get_dimm_attr(u32 reg, int lo
 }
 
 #define IS_DIMM_PRESENT(mtr)		GET_BITFIELD((mtr), 15, 15)
+#define IS_NVDIMM_PRESENT(mcddrtcfg, i)	GET_BITFIELD((mcddrtcfg), (i), (i))
 
 #define numrank(reg) get_dimm_attr((reg), 12, 13, 0, 0, 2, "ranks")
 #define numrow(reg) get_dimm_attr((reg), 2, 4, 12, 1, 6, "rows")
@@ -352,8 +356,6 @@ static int get_dimm_info(u32 mtr, u32 am
 	int  banks = 16, ranks, rows, cols, npages;
 	u64 size;
 
-	if (!IS_DIMM_PRESENT(mtr))
-		return 0;
 	ranks = numrank(mtr);
 	rows = numrow(mtr);
 	cols = numcol(mtr);
@@ -385,6 +387,54 @@ static int get_dimm_info(u32 mtr, u32 am
 	return 1;
 }
 
+static int get_nvdimm_info(struct dimm_info *dimm, struct skx_imc *imc,
+			   int chan, int dimmno)
+{
+	int smbios_handle;
+	u32 dev_handle;
+	u16 flags;
+	u64 size = 0;
+
+	dev_handle = ACPI_NFIT_BUILD_DEVICE_HANDLE(dimmno, chan, imc->lmc,
+						   imc->src_id, 0);
+
+	smbios_handle = nfit_get_smbios_id(dev_handle, &flags);
+	if (smbios_handle == -EOPNOTSUPP) {
+		pr_warn_once(EDAC_MOD_STR ": Can't find size of NVDIMM. Try enabling CONFIG_ACPI_NFIT\n");
+		goto unknown_size;
+	}
+
+	if (smbios_handle < 0) {
+		skx_printk(KERN_ERR, "Can't find handle for NVDIMM ADR=%x\n", dev_handle);
+		goto unknown_size;
+	}
+
+	if (flags & ACPI_NFIT_MEM_MAP_FAILED) {
+		skx_printk(KERN_ERR, "NVDIMM ADR=%x is not mapped\n", dev_handle);
+		goto unknown_size;
+	}
+
+	size = dmi_memdev_size(smbios_handle);
+	if (size == ~0ull)
+		skx_printk(KERN_ERR, "Can't find size for NVDIMM ADR=%x/SMBIOS=%x\n",
+			   dev_handle, smbios_handle);
+
+unknown_size:
+	dimm->nr_pages = size >> PAGE_SHIFT;
+	dimm->grain = 32;
+	dimm->dtype = DEV_UNKNOWN;
+	dimm->mtype = MEM_NVDIMM;
+	dimm->edac_mode = EDAC_SECDED; /* likely better than this */
+
+	edac_dbg(0, "mc#%d: channel %d, dimm %d, %llu Mb (%u pages)\n",
+		 imc->mc, chan, dimmno, size >> 20, dimm->nr_pages);
+
+	snprintf(dimm->label, sizeof(dimm->label), "CPU_SrcID#%u_MC#%u_Chan#%u_DIMM#%u",
+		 imc->src_id, imc->lmc, chan, dimmno);
+
+	return (size == 0 || size == ~0ull) ? 0 : 1;
+}
+
 #define SKX_GET_MTMTR(dev, reg) \
 	pci_read_config_dword((dev), 0x87c, &reg)
 
@@ -401,20 +451,24 @@ static int skx_get_dimm_config(struct me
 {
 	struct skx_pvt *pvt = mci->pvt_info;
 	struct skx_imc *imc = pvt->imc;
+	u32 mtr, amap, mcddrtcfg;
 	struct dimm_info *dimm;
 	int i, j;
-	u32 mtr, amap;
 	int ndimms;
 
 	for (i = 0; i < NUM_CHANNELS; i++) {
 		ndimms = 0;
 		pci_read_config_dword(imc->chan[i].cdev, 0x8C, &amap);
+		pci_read_config_dword(imc->chan[i].cdev, 0x400, &mcddrtcfg);
 		for (j = 0; j < NUM_DIMMS; j++) {
 			dimm = EDAC_DIMM_PTR(mci->layers, mci->dimms,
 					     mci->n_layers, i, j, 0);
 			pci_read_config_dword(imc->chan[i].cdev,
 					0x80 + 4*j, &mtr);
-			ndimms += get_dimm_info(mtr, amap, dimm, imc, i, j);
+			if (IS_DIMM_PRESENT(mtr))
+				ndimms += get_dimm_info(mtr, amap, dimm, imc, i, j);
+			else if (IS_NVDIMM_PRESENT(mcddrtcfg, j))
+				ndimms += get_nvdimm_info(dimm, imc, i, j);
 		}
 		if (ndimms && !skx_check_ecc(imc->chan[0].cdev)) {
 			skx_printk(KERN_ERR, "ECC is disabled on imc %d\n", imc->mc);
@@ -472,7 +526,7 @@ static int skx_register_mci(struct skx_i
 
 	mci->ctl_name = kasprintf(GFP_KERNEL, "Skylake Socket#%d IMC#%d",
 				  imc->node_id, imc->lmc);
-	mci->mtype_cap = MEM_FLAG_DDR4;
+	mci->mtype_cap = MEM_FLAG_DDR4 | MEM_FLAG_NVDIMM;
 	mci->edac_ctl_cap = EDAC_FLAG_NONE;
 	mci->edac_cap = EDAC_FLAG_NONE;
 	mci->mod_name = EDAC_MOD_STR;