From 76239f441c9455edd5a0784a3117de03d55d1b17 Mon Sep 17 00:00:00 2001
From: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Date: Thu, 31 Jul 2025 22:55:28 +0800
Subject: [PATCH 01/11] EDAC/{skx_common,skx}: Use configuration data, not
 global macros

commit 219af5dfce98fe254335ea79c2bf98428c38370c upstream.

Use model-specific configuration data for the number of memory controllers
per socket, channels per memory controller, and DIMMs per channel as
intended, instead of relying on global macros for maximum values.

No functional changes intended.

Intel-SIG: commit 219af5dfce98 EDAC/{skx_common,skx}: Use configuration data, not global macros
Backport EDAC for DMR

Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://lore.kernel.org/r/20250731145534.2759334-2-qiuxu.zhuo@intel.com
[ Zhang Rui: amend change log ]
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
---
 drivers/edac/skx_base.c   | 33 ++++++++++++++++++++-------------
 drivers/edac/skx_common.c | 16 +++++++++-------
 drivers/edac/skx_common.h |  1 +
 3 files changed, 30 insertions(+), 20 deletions(-)

diff --git a/drivers/edac/skx_base.c b/drivers/edac/skx_base.c
index 67634d3af4617..78282c8e3444e 100644
--- a/drivers/edac/skx_base.c
+++ b/drivers/edac/skx_base.c
@@ -33,6 +33,15 @@ static unsigned int nvdimm_count;
 #define	MASK26	0x3FFFFFF		/* Mask for 2^26 */
 #define MASK29	0x1FFFFFFF		/* Mask for 2^29 */
 
+static struct res_config skx_cfg = {
+	.type			= SKX,
+	.decs_did		= 0x2016,
+	.busno_cfg_offset	= 0xcc,
+	.ddr_imc_num		= 2,
+	.ddr_chan_num		= 3,
+	.ddr_dimm_num		= 2,
+};
+
 static struct skx_dev *get_skx_dev(struct pci_bus *bus, u8 idx)
 {
 	struct skx_dev *d;
@@ -52,7 +61,7 @@ enum munittype {
 
 struct munit {
 	u16	did;
-	u16	devfn[SKX_NUM_IMC];
+	u16	devfn[2];
 	u8	busidx;
 	u8	per_socket;
 	enum munittype mtype;
@@ -89,11 +98,11 @@ static int get_all_munits(const struct munit *m)
 		if (!pdev)
 			break;
 		ndev++;
-		if (m->per_socket == SKX_NUM_IMC) {
-			for (i = 0; i < SKX_NUM_IMC; i++)
+		if (m->per_socket == skx_cfg.ddr_imc_num) {
+			for (i = 0; i < skx_cfg.ddr_imc_num; i++)
 				if (m->devfn[i] == pdev->devfn)
 					break;
-			if (i == SKX_NUM_IMC)
+			if (i == skx_cfg.ddr_imc_num)
 				goto fail;
 		}
 		d = get_skx_dev(pdev->bus, m->busidx);
@@ -157,12 +166,6 @@ static int get_all_munits(const struct munit *m)
 	return -ENODEV;
 }
 
-static struct res_config skx_cfg = {
-	.type			= SKX,
-	.decs_did		= 0x2016,
-	.busno_cfg_offset	= 0xcc,
-};
-
 static const struct x86_cpu_id skx_cpuids[] = {
 	X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(SKYLAKE_X, X86_STEPPINGS(0x0, 0xf), &skx_cfg),
 	{ }
@@ -186,11 +189,11 @@ static int skx_get_dimm_config(struct mem_ctl_info *mci, struct res_config *cfg)
 	/* Only the mcmtr on the first channel is effective */
 	pci_read_config_dword(imc->chan[0].cdev, 0x87c, &mcmtr);
 
-	for (i = 0; i < SKX_NUM_CHANNELS; i++) {
+	for (i = 0; i < cfg->ddr_chan_num; 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 < SKX_NUM_DIMMS; j++) {
+		for (j = 0; j < cfg->ddr_dimm_num; j++) {
 			dimm = edac_get_dimm(mci, i, j, 0);
 			pci_read_config_dword(imc->chan[i].cdev,
 					      0x80 + 4 * j, &mtr);
@@ -620,6 +623,7 @@ static int __init skx_init(void)
 		return -ENODEV;
 
 	cfg = (struct res_config *)id->driver_data;
+	skx_set_res_cfg(cfg);
 
 	rc = skx_get_hi_lo(0x2034, off, &skx_tolm, &skx_tohm);
 	if (rc)
@@ -652,10 +656,13 @@ static int __init skx_init(void)
 			goto fail;
 
 		edac_dbg(2, "src_id = %d\n", src_id);
-		for (i = 0; i < SKX_NUM_IMC; i++) {
+		for (i = 0; i < cfg->ddr_imc_num; i++) {
 			d->imc[i].mc = mc++;
 			d->imc[i].lmc = i;
 			d->imc[i].src_id = src_id;
+			d->imc[i].num_channels = cfg->ddr_chan_num;
+			d->imc[i].num_dimms    = cfg->ddr_dimm_num;
+
 			rc = skx_register_mci(&d->imc[i], d->imc[i].chan[0].cdev,
 					      "Skylake Socket", EDAC_MOD_STR,
 					      skx_get_dimm_config, cfg);
diff --git a/drivers/edac/skx_common.c b/drivers/edac/skx_common.c
index d9cd4a3b27736..24cdf57b20e37 100644
--- a/drivers/edac/skx_common.c
+++ b/drivers/edac/skx_common.c
@@ -322,10 +322,10 @@ static int get_width(u32 mtr)
  */
 int skx_get_all_bus_mappings(struct res_config *cfg, struct list_head **list)
 {
+	int ndev = 0, imc_num = cfg->ddr_imc_num + cfg->hbm_imc_num;
 	struct pci_dev *pdev, *prev;
 	struct skx_dev *d;
 	u32 reg;
-	int ndev = 0;
 
 	prev = NULL;
 	for (;;) {
@@ -356,8 +356,10 @@ int skx_get_all_bus_mappings(struct res_config *cfg, struct list_head **list)
 			d->seg = GET_BITFIELD(reg, 16, 23);
 		}
 
-		edac_dbg(2, "busses: 0x%x, 0x%x, 0x%x, 0x%x\n",
-			 d->bus[0], d->bus[1], d->bus[2], d->bus[3]);
+		d->num_imc = imc_num;
+
+		edac_dbg(2, "busses: 0x%x, 0x%x, 0x%x, 0x%x, imcs %d\n",
+			 d->bus[0], d->bus[1], d->bus[2], d->bus[3], imc_num);
 		list_add_tail(&d->list, &dev_edac_list);
 		prev = pdev;
 
@@ -546,10 +548,10 @@ int skx_register_mci(struct skx_imc *imc, struct pci_dev *pdev,
 
 	/* Allocate a new MC control structure */
 	layers[0].type = EDAC_MC_LAYER_CHANNEL;
-	layers[0].size = NUM_CHANNELS;
+	layers[0].size = imc->num_channels;
 	layers[0].is_virt_csrow = false;
 	layers[1].type = EDAC_MC_LAYER_SLOT;
-	layers[1].size = NUM_DIMMS;
+	layers[1].size = imc->num_dimms;
 	layers[1].is_virt_csrow = true;
 	mci = edac_mc_alloc(imc->mc, ARRAY_SIZE(layers), layers,
 			    sizeof(struct skx_pvt));
@@ -789,7 +791,7 @@ void skx_remove(void)
 
 	list_for_each_entry_safe(d, tmp, &dev_edac_list, list) {
 		list_del(&d->list);
-		for (i = 0; i < NUM_IMC; i++) {
+		for (i = 0; i < d->num_imc; i++) {
 			if (d->imc[i].mci)
 				skx_unregister_mci(&d->imc[i]);
 
@@ -799,7 +801,7 @@ void skx_remove(void)
 			if (d->imc[i].mbase)
 				iounmap(d->imc[i].mbase);
 
-			for (j = 0; j < NUM_CHANNELS; j++) {
+			for (j = 0; j < d->imc[i].num_channels; j++) {
 				if (d->imc[i].chan[j].cdev)
 					pci_dev_put(d->imc[i].chan[j].cdev);
 			}
diff --git a/drivers/edac/skx_common.h b/drivers/edac/skx_common.h
index ec4966f7ea40b..3f6007a972679 100644
--- a/drivers/edac/skx_common.h
+++ b/drivers/edac/skx_common.h
@@ -134,6 +134,7 @@ struct skx_dev {
 	struct pci_dev *uracu; /* for i10nm CPU */
 	struct pci_dev *pcu_cr3; /* for HBM memory detection */
 	u32 mcroute;
+	int num_imc;
 	/*
 	 * Some server BIOS may hide certain memory controllers, and the
 	 * EDAC driver skips those hidden memory controllers. However, the

From 88cf6f3a824e2900bd005e658bd775028ca5a1b3 Mon Sep 17 00:00:00 2001
From: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Date: Thu, 31 Jul 2025 22:55:29 +0800
Subject: [PATCH 02/11] EDAC/skx_common: Move mc_mapping to be a field inside
 struct skx_imc

commit 59cfc06a874e01633865d0b05eba47b09b8b3a8f upstream.

The mc_mapping and imc fields of struct skx_dev have the same size,
NUM_IMC. Move mc_mapping to be a field inside struct skx_imc to prepare
for making the imc array of memory controller instances a flexible array.

No functional changes intended.

Intel-SIG: commit 59cfc06a874e EDAC/skx_common: Move mc_mapping to be a field inside struct skx_imc
Backport EDAC for DMR

Suggested-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://lore.kernel.org/r/20250731145534.2759334-3-qiuxu.zhuo@intel.com
[ Zhang Rui: amend change log ]
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
---
 drivers/edac/skx_common.c |  8 ++++----
 drivers/edac/skx_common.h | 20 ++++++++++----------
 2 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/drivers/edac/skx_common.c b/drivers/edac/skx_common.c
index 24cdf57b20e37..c3cd478d02f26 100644
--- a/drivers/edac/skx_common.c
+++ b/drivers/edac/skx_common.c
@@ -133,7 +133,7 @@ static void skx_init_mc_mapping(struct skx_dev *d)
 	 * EDAC driver.
 	 */
 	for (int i = 0; i < NUM_IMC; i++)
-		d->mc_mapping[i] = i;
+		d->imc[i].mc_mapping = i;
 }
 
 void skx_set_mc_mapping(struct skx_dev *d, u8 pmc, u8 lmc)
@@ -141,16 +141,16 @@ void skx_set_mc_mapping(struct skx_dev *d, u8 pmc, u8 lmc)
 	edac_dbg(0, "Set the mapping of mc phy idx to logical idx: %02d -> %02d\n",
 		 pmc, lmc);
 
-	d->mc_mapping[pmc] = lmc;
+	d->imc[pmc].mc_mapping = lmc;
 }
 EXPORT_SYMBOL_GPL(skx_set_mc_mapping);
 
 static u8 skx_get_mc_mapping(struct skx_dev *d, u8 pmc)
 {
 	edac_dbg(0, "Get the mapping of mc phy idx to logical idx: %02d -> %02d\n",
-		 pmc, d->mc_mapping[pmc]);
+		 pmc, d->imc[pmc].mc_mapping);
 
-	return d->mc_mapping[pmc];
+	return d->imc[pmc].mc_mapping;
 }
 
 static bool skx_adxl_decode(struct decoded_addr *res, enum error_source err_src)
diff --git a/drivers/edac/skx_common.h b/drivers/edac/skx_common.h
index 3f6007a972679..95d61d23f89ef 100644
--- a/drivers/edac/skx_common.h
+++ b/drivers/edac/skx_common.h
@@ -135,16 +135,6 @@ struct skx_dev {
 	struct pci_dev *pcu_cr3; /* for HBM memory detection */
 	u32 mcroute;
 	int num_imc;
-	/*
-	 * Some server BIOS may hide certain memory controllers, and the
-	 * EDAC driver skips those hidden memory controllers. However, the
-	 * ADXL still decodes memory error address using physical memory
-	 * controller indices. The mapping table is used to convert the
-	 * physical indices (reported by ADXL) to the logical indices
-	 * (used the EDAC driver) of present memory controllers during the
-	 * error handling process.
-	 */
-	u8 mc_mapping[NUM_IMC];
 	struct skx_imc {
 		struct mem_ctl_info *mci;
 		struct pci_dev *mdev; /* for i10nm CPU */
@@ -156,6 +146,16 @@ struct skx_dev {
 		u8 mc;	/* system wide mc# */
 		u8 lmc;	/* socket relative mc# */
 		u8 src_id;
+		/*
+		 * Some server BIOS may hide certain memory controllers, and the
+		 * EDAC driver skips those hidden memory controllers. However, the
+		 * ADXL still decodes memory error address using physical memory
+		 * controller indices. The mapping table is used to convert the
+		 * physical indices (reported by ADXL) to the logical indices
+		 * (used the EDAC driver) of present memory controllers during the
+		 * error handling process.
+		 */
+		u8 mc_mapping;
 		struct skx_channel {
 			struct pci_dev	*cdev;
 			struct pci_dev	*edev;

From 9b293522ebbcde4b75a0146a9174999730bfe821 Mon Sep 17 00:00:00 2001
From: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Date: Thu, 31 Jul 2025 22:55:30 +0800
Subject: [PATCH 03/11] EDAC/skx_common: Swap memory controller index mapping

commit 30b47b71fdc0091db5a4fa9503ad630aeb0ab3eb upstream.

The current mapping of memory controller indices is from physical index [1]
to logical index [2], as show below:

  skx_dev->imc[pmc].mc_mapping = lmc

Since skx_dev->imc[] is an array of present memory controller instances,
mapping memory controller indices from logical index to physical index,
as show below, is more reasonable. This is also a preparatory step for
making skx_dev->imc[] a flexible array.

  skx_dev->imc[lmc].mc_mapping = pmc

Both mappings are equivalent. No functional changes intended.

[1] Indices for memory controllers include both those present to the
    OS and those disabled by BIOS.

[2] Indices for memory controllers present to the OS.

Intel-SIG: commit 30b47b71fdc0 EDAC/skx_common: Swap memory controller index mapping
Backport EDAC for DMR

Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://lore.kernel.org/r/20250731145534.2759334-4-qiuxu.zhuo@intel.com
[ Zhang Rui: amend change log ]
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
---
 drivers/edac/skx_common.c | 28 ++++++++++++++++++++--------
 1 file changed, 20 insertions(+), 8 deletions(-)

diff --git a/drivers/edac/skx_common.c b/drivers/edac/skx_common.c
index c3cd478d02f26..e9af4f716a60e 100644
--- a/drivers/edac/skx_common.c
+++ b/drivers/edac/skx_common.c
@@ -132,7 +132,7 @@ static void skx_init_mc_mapping(struct skx_dev *d)
 	 * the logical indices of the memory controllers enumerated by the
 	 * EDAC driver.
 	 */
-	for (int i = 0; i < NUM_IMC; i++)
+	for (int i = 0; i < d->num_imc; i++)
 		d->imc[i].mc_mapping = i;
 }
 
@@ -141,22 +141,28 @@ void skx_set_mc_mapping(struct skx_dev *d, u8 pmc, u8 lmc)
 	edac_dbg(0, "Set the mapping of mc phy idx to logical idx: %02d -> %02d\n",
 		 pmc, lmc);
 
-	d->imc[pmc].mc_mapping = lmc;
+	d->imc[lmc].mc_mapping = pmc;
 }
 EXPORT_SYMBOL_GPL(skx_set_mc_mapping);
 
-static u8 skx_get_mc_mapping(struct skx_dev *d, u8 pmc)
+static int skx_get_mc_mapping(struct skx_dev *d, u8 pmc)
 {
-	edac_dbg(0, "Get the mapping of mc phy idx to logical idx: %02d -> %02d\n",
-		 pmc, d->imc[pmc].mc_mapping);
+	for (int lmc = 0; lmc < d->num_imc; lmc++) {
+		if (d->imc[lmc].mc_mapping == pmc) {
+			edac_dbg(0, "Get the mapping of mc phy idx to logical idx: %02d -> %02d\n",
+				 pmc, lmc);
 
-	return d->imc[pmc].mc_mapping;
+			return lmc;
+		}
+	}
+
+	return -1;
 }
 
 static bool skx_adxl_decode(struct decoded_addr *res, enum error_source err_src)
 {
+	int i, lmc, len = 0;
 	struct skx_dev *d;
-	int i, len = 0;
 
 	if (res->addr >= skx_tohm || (res->addr >= skx_tolm &&
 				      res->addr < BIT_ULL(32))) {
@@ -220,7 +226,13 @@ static bool skx_adxl_decode(struct decoded_addr *res, enum error_source err_src)
 		return false;
 	}
 
-	res->imc = skx_get_mc_mapping(d, res->imc);
+	lmc = skx_get_mc_mapping(d, res->imc);
+	if (lmc < 0) {
+		skx_printk(KERN_ERR, "No lmc for imc %d\n", res->imc);
+		return false;
+	}
+
+	res->imc = lmc;
 
 	for (i = 0; i < adxl_component_count; i++) {
 		if (adxl_values[i] == ~0x0ull)

From 7c8adb70a4315c698830212876db58fcb1654155 Mon Sep 17 00:00:00 2001
From: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Date: Thu, 31 Jul 2025 22:55:31 +0800
Subject: [PATCH 04/11] EDAC/skx_common: Make skx_dev->imc[] a flexible array

commit 43060ca5332462903f57c2ff9b49b69124618070 upstream.

The current skx->imc[NUM_IMC] array of memory controller instances is
sized using the macro NUM_IMC. Each time EDAC support is added for a
new CPU, NUM_IMC needs to be updated to ensure it is greater than or
equal to the number of memory controllers for the new CPU. This approach
is inconvenient and results in memory waste for older CPUs with fewer
memory controllers.

To address this, make skx->imc[] a flexible array and determine its size
from configuration data or at runtime.

Intel-SIG: commit 43060ca53324 EDAC/skx_common: Make skx_dev->imc[] a flexible array
Backport EDAC for DMR

Suggested-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://lore.kernel.org/r/20250731145534.2759334-5-qiuxu.zhuo@intel.com
[ Zhang Rui: amend change log ]
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
---
 drivers/edac/skx_common.c | 3 ++-
 drivers/edac/skx_common.h | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/edac/skx_common.c b/drivers/edac/skx_common.c
index e9af4f716a60e..e7851b92f1c20 100644
--- a/drivers/edac/skx_common.c
+++ b/drivers/edac/skx_common.c
@@ -17,6 +17,7 @@
 #include <linux/acpi.h>
 #include <linux/dmi.h>
 #include <linux/adxl.h>
+#include <linux/overflow.h>
 #include <acpi/nfit.h>
 #include <asm/mce.h>
 #include <asm/uv/uv.h>
@@ -345,7 +346,7 @@ int skx_get_all_bus_mappings(struct res_config *cfg, struct list_head **list)
 		if (!pdev)
 			break;
 		ndev++;
-		d = kzalloc(sizeof(*d), GFP_KERNEL);
+		d = kzalloc(struct_size(d, imc, imc_num), GFP_KERNEL);
 		if (!d) {
 			pci_dev_put(pdev);
 			return -ENOMEM;
diff --git a/drivers/edac/skx_common.h b/drivers/edac/skx_common.h
index 95d61d23f89ef..e7038fd45d063 100644
--- a/drivers/edac/skx_common.h
+++ b/drivers/edac/skx_common.h
@@ -172,7 +172,7 @@ struct skx_dev {
 				u8 colbits;
 			} dimms[NUM_DIMMS];
 		} chan[NUM_CHANNELS];
-	} imc[NUM_IMC];
+	} imc[];
 };
 
 struct skx_pvt {

From 38a3a68d09e98d6a4a6b0a8077b97d0b9ec6edec Mon Sep 17 00:00:00 2001
From: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Date: Wed, 19 Nov 2025 12:11:40 -0800
Subject: [PATCH 05/11] EDAC/{skx_common,skx,i10nm}: Make skx_register_mci()
 independent of pci_dev

commit b3d70059cbb262eef12927dbcf37ba8586d4a3ab upstream.

Memory controllers in the new Intel server CPUs, such as Diamond Rapids,
are presented as MMIO-based devices rather than PCI devices.
Modify skx_register_mci() to be independent of 'pci_dev' and use a generic
'dev' of 'struct device' to prepare for support of such MMIO-based memory
controllers.

Intel-SIG: commit b3d70059cbb2 EDAC/{skx_common,skx,i10nm}: Make skx_register_mci() independent of pci_dev
Backport EDAC for DMR

Tested-by: Yi Lai <yi1.lai@intel.com>
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://patch.msgid.link/20251119134132.2389472-2-qiuxu.zhuo@intel.com
[ Zhang Rui: amend change log ]
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
---
 drivers/edac/i10nm_base.c |  3 ++-
 drivers/edac/skx_base.c   |  4 ++--
 drivers/edac/skx_common.c | 10 +++++-----
 drivers/edac/skx_common.h |  2 +-
 4 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/drivers/edac/i10nm_base.c b/drivers/edac/i10nm_base.c
index ab4d3e483618d..efcb910015ec0 100644
--- a/drivers/edac/i10nm_base.c
+++ b/drivers/edac/i10nm_base.c
@@ -1197,7 +1197,8 @@ static int __init i10nm_init(void)
 				d->imc[i].num_dimms    = cfg->ddr_dimm_num;
 			}
 
-			rc = skx_register_mci(&d->imc[i], d->imc[i].mdev,
+			rc = skx_register_mci(&d->imc[i], &d->imc[i].mdev->dev,
+					      pci_name(d->imc[i].mdev),
 					      "Intel_10nm Socket", EDAC_MOD_STR,
 					      i10nm_get_dimm_config, cfg);
 			if (rc < 0)
diff --git a/drivers/edac/skx_base.c b/drivers/edac/skx_base.c
index 78282c8e3444e..8246e5dd2b61c 100644
--- a/drivers/edac/skx_base.c
+++ b/drivers/edac/skx_base.c
@@ -662,8 +662,8 @@ static int __init skx_init(void)
 			d->imc[i].src_id = src_id;
 			d->imc[i].num_channels = cfg->ddr_chan_num;
 			d->imc[i].num_dimms    = cfg->ddr_dimm_num;
-
-			rc = skx_register_mci(&d->imc[i], d->imc[i].chan[0].cdev,
+			rc = skx_register_mci(&d->imc[i], &d->imc[i].chan[0].cdev->dev,
+					      pci_name(d->imc[i].chan[0].cdev),
 					      "Skylake Socket", EDAC_MOD_STR,
 					      skx_get_dimm_config, cfg);
 			if (rc < 0)
diff --git a/drivers/edac/skx_common.c b/drivers/edac/skx_common.c
index e7851b92f1c20..ef1b50d151d55 100644
--- a/drivers/edac/skx_common.c
+++ b/drivers/edac/skx_common.c
@@ -549,9 +549,9 @@ int skx_get_nvdimm_info(struct dimm_info *dimm, struct skx_imc *imc,
 }
 EXPORT_SYMBOL_GPL(skx_get_nvdimm_info);
 
-int skx_register_mci(struct skx_imc *imc, struct pci_dev *pdev,
-		     const char *ctl_name, const char *mod_str,
-		     get_dimm_config_f get_dimm_config,
+int skx_register_mci(struct skx_imc *imc, struct device *dev,
+		     const char *dev_name, const char *ctl_name,
+		     const char *mod_str, get_dimm_config_f get_dimm_config,
 		     struct res_config *cfg)
 {
 	struct mem_ctl_info *mci;
@@ -592,7 +592,7 @@ int skx_register_mci(struct skx_imc *imc, struct pci_dev *pdev,
 	mci->edac_ctl_cap = EDAC_FLAG_NONE;
 	mci->edac_cap = EDAC_FLAG_NONE;
 	mci->mod_name = mod_str;
-	mci->dev_name = pci_name(pdev);
+	mci->dev_name = dev_name;
 	mci->ctl_page_to_phys = NULL;
 
 	rc = get_dimm_config(mci, cfg);
@@ -600,7 +600,7 @@ int skx_register_mci(struct skx_imc *imc, struct pci_dev *pdev,
 		goto fail;
 
 	/* Record ptr to the generic device */
-	mci->pdev = &pdev->dev;
+	mci->pdev = dev;
 
 	/* Add this new MC control structure to EDAC's list of MCs */
 	if (unlikely(edac_mc_add_mc(mci))) {
diff --git a/drivers/edac/skx_common.h b/drivers/edac/skx_common.h
index e7038fd45d063..24e1a93bcd982 100644
--- a/drivers/edac/skx_common.h
+++ b/drivers/edac/skx_common.h
@@ -307,7 +307,7 @@ int skx_get_dimm_info(u32 mtr, u32 mcmtr, u32 amap, struct dimm_info *dimm,
 int skx_get_nvdimm_info(struct dimm_info *dimm, struct skx_imc *imc,
 			int chan, int dimmno, const char *mod_str);
 
-int skx_register_mci(struct skx_imc *imc, struct pci_dev *pdev,
+int skx_register_mci(struct skx_imc *imc, struct device *dev, const char *dev_name,
 		     const char *ctl_name, const char *mod_str,
 		     get_dimm_config_f get_dimm_config,
 		     struct res_config *cfg);

From 878af15f92a6def7b16cb5fbcdf7d061ebfa91b9 Mon Sep 17 00:00:00 2001
From: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Date: Wed, 19 Nov 2025 12:11:40 -0800
Subject: [PATCH 06/11] EDAC/skx_common: Prepare for skx_get_edac_list()

commit 9529e697739e2d4dc8c4129bbe91576f744f79f6 upstream.

The Intel EDAC library 'skx_common' maintains the Intel server EDAC device
list for {skx, i10nm}_edac drivers, which use skx_get_all_bus_mappings()
to build and retrieve the EDAC device list.

However, the upcoming Intel EDAC driver, imh_edac, for Diamond Rapids
servers is designed for memory controllers that are MMIO-based devices
rather than PCI devices. Consequently, it can't use
skx_get_all_bus_mappings() due to the absence of a PCI bus. To accommodate
this, prepare skx_get_edac_list() to enable the upcoming imh_edac driver
to obtain the EDAC device list from the skx_common library and build the
EDAC device list independently.

Intel-SIG: commit 9529e697739e EDAC/skx_common: Prepare for skx_get_edac_list()
Backport EDAC for DMR

Tested-by: Yi Lai <yi1.lai@intel.com>
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://patch.msgid.link/20251119134132.2389472-3-qiuxu.zhuo@intel.com
[ Zhang Rui: amend change log ]
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
---
 drivers/edac/skx_common.c | 6 ++++++
 drivers/edac/skx_common.h | 2 ++
 2 files changed, 8 insertions(+)

diff --git a/drivers/edac/skx_common.c b/drivers/edac/skx_common.c
index ef1b50d151d55..f70666a19dffa 100644
--- a/drivers/edac/skx_common.c
+++ b/drivers/edac/skx_common.c
@@ -385,6 +385,12 @@ int skx_get_all_bus_mappings(struct res_config *cfg, struct list_head **list)
 }
 EXPORT_SYMBOL_GPL(skx_get_all_bus_mappings);
 
+struct list_head *skx_get_edac_list(void)
+{
+	return &dev_edac_list;
+}
+EXPORT_SYMBOL_GPL(skx_get_edac_list);
+
 int skx_get_hi_lo(unsigned int did, int off[], u64 *tolm, u64 *tohm)
 {
 	struct pci_dev *pdev;
diff --git a/drivers/edac/skx_common.h b/drivers/edac/skx_common.h
index 24e1a93bcd982..cf364a7936f9d 100644
--- a/drivers/edac/skx_common.h
+++ b/drivers/edac/skx_common.h
@@ -298,6 +298,8 @@ int skx_get_src_id(struct skx_dev *d, int off, u8 *id);
 
 int skx_get_all_bus_mappings(struct res_config *cfg, struct list_head **list);
 
+struct list_head *skx_get_edac_list(void);
+
 int skx_get_hi_lo(unsigned int did, int off[], u64 *tolm, u64 *tohm);
 
 int skx_get_dimm_info(u32 mtr, u32 mcmtr, u32 amap, struct dimm_info *dimm,

From 27666c837805fc18990fe0739c4aa8ea1698c7a7 Mon Sep 17 00:00:00 2001
From: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Date: Wed, 19 Nov 2025 12:11:40 -0800
Subject: [PATCH 07/11] EDAC/skx_common: Prepare for skx_set_hi_lo()

commit d4839582bc7002095b013acb4a2dcaa1438c41aa upstream.

The upcoming imh_edac driver for Intel Diamond Rapids servers cannot
use skx_get_hi_lo() in skx_common to retrieve the TOHM (Top of High
Memory) and TOLM (Top of Low Memory) parameters. Instead, it obtains
these parameters within its own EDAC driver. To accommodate this,
prepare skx_set_hi_lo() to allow the driver to notify skx_common of
these parameters.

Intel-SIG: commit d4839582bc70 EDAC/skx_common: Prepare for skx_set_hi_lo()
Backport EDAC for DMR

Tested-by: Yi Lai <yi1.lai@intel.com>
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://patch.msgid.link/20251119134132.2389472-4-qiuxu.zhuo@intel.com
[ Zhang Rui: amend change log ]
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
---
 drivers/edac/skx_common.c | 7 +++++++
 drivers/edac/skx_common.h | 1 +
 2 files changed, 8 insertions(+)

diff --git a/drivers/edac/skx_common.c b/drivers/edac/skx_common.c
index f70666a19dffa..38603509efab0 100644
--- a/drivers/edac/skx_common.c
+++ b/drivers/edac/skx_common.c
@@ -431,6 +431,13 @@ int skx_get_hi_lo(unsigned int did, int off[], u64 *tolm, u64 *tohm)
 }
 EXPORT_SYMBOL_GPL(skx_get_hi_lo);
 
+void skx_set_hi_lo(u64 tolm, u64 tohm)
+{
+	skx_tolm = tolm;
+	skx_tohm = tohm;
+}
+EXPORT_SYMBOL_GPL(skx_set_hi_lo);
+
 static int skx_get_dimm_attr(u32 reg, int lobit, int hibit, int add,
 			     int minval, int maxval, const char *name)
 {
diff --git a/drivers/edac/skx_common.h b/drivers/edac/skx_common.h
index cf364a7936f9d..93f50ab4153f9 100644
--- a/drivers/edac/skx_common.h
+++ b/drivers/edac/skx_common.h
@@ -301,6 +301,7 @@ int skx_get_all_bus_mappings(struct res_config *cfg, struct list_head **list);
 struct list_head *skx_get_edac_list(void);
 
 int skx_get_hi_lo(unsigned int did, int off[], u64 *tolm, u64 *tohm);
+void skx_set_hi_lo(u64 tolm, u64 tohm);
 
 int skx_get_dimm_info(u32 mtr, u32 mcmtr, u32 amap, struct dimm_info *dimm,
 		      struct skx_imc *imc, int chan, int dimmno,

From bf4a949ec2c906bd70d33eec29a486fafbfea6be Mon Sep 17 00:00:00 2001
From: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Date: Wed, 19 Nov 2025 12:11:40 -0800
Subject: [PATCH 08/11] EDAC/{skx_common,imh}: Add EDAC driver for Intel
 Diamond Rapids servers

commit 9fc67b11703fe9d8a5617ccacec2a452e455fa52 upstream.

Intel Diamond Rapids CPUs include Integrated Memory and I/O Hubs (IMH).
The memory controllers within the IMHs provide memory stacks to the
processor. Create a new driver for this IMH-based memory controllers
rather than applying additional patches to the existing i10nm_edac.c
for the following reasons:

1) The memory controllers are not presented as PCI devices; instead,
   the detection and all their registers have been transitioned to
   MMIO-based memory spaces.

2) Validation processes are costly. Modifications to i10nm_edac would
   require extensive validation checks against multiple platforms,
   including Ice Lake, Sapphire Rapids, Emerald Rapids, Granite Rapids,
   Sierra Forest, and Grand Ridge.

3) Future Intel CPUs will likely only need patches on top of this new
   EDAC driver. Validation can be limited to Diamond Rapids servers
   and future Intel CPU generations.

[Tony: Fix kerneldoc for struct local_reg]
[randconfig: Added dependencies on NFIT and DMI]

Intel-SIG: commit 9fc67b11703f EDAC/{skx_common,imh}: Add EDAC driver for Intel Diamond Rapids servers
Backport EDAC for DMR

Tested-by: Yi Lai <yi1.lai@intel.com>
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://patch.msgid.link/20251119134132.2389472-5-qiuxu.zhuo@intel.com
[ Zhang Rui: amend change log ]
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
---
 drivers/edac/Kconfig      |  12 +
 drivers/edac/Makefile     |   3 +
 drivers/edac/imh_base.c   | 562 ++++++++++++++++++++++++++++++++++++++
 drivers/edac/skx_common.c |   8 +-
 drivers/edac/skx_common.h |  89 ++++--
 5 files changed, 648 insertions(+), 26 deletions(-)
 create mode 100644 drivers/edac/imh_base.c

diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
index 41a215f230f0f..ab43465e19a7e 100644
--- a/drivers/edac/Kconfig
+++ b/drivers/edac/Kconfig
@@ -263,6 +263,18 @@ config EDAC_I10NM
 	  system has non-volatile DIMMs you should also manually
 	  select CONFIG_ACPI_NFIT.
 
+config EDAC_IMH
+	tristate "Intel Integrated Memory/IO Hub MC"
+	depends on X86_64 && X86_MCE_INTEL && ACPI
+	depends on ACPI_NFIT || !ACPI_NFIT # if ACPI_NFIT=m, EDAC_IMH can't be y
+	select DMI
+	select ACPI_ADXL
+	help
+	  Support for error detection and correction the Intel
+	  Integrated Memory/IO Hub Memory Controller. This MC IP is
+	  first used on the Diamond Rapids servers but may appear on
+	  others in the future.
+
 config EDAC_PND2
 	tristate "Intel Pondicherry2"
 	depends on PCI && X86_64 && X86_MCE_INTEL
diff --git a/drivers/edac/Makefile b/drivers/edac/Makefile
index 446364264e2b1..b0a121bf4e1e8 100644
--- a/drivers/edac/Makefile
+++ b/drivers/edac/Makefile
@@ -67,6 +67,9 @@ obj-$(CONFIG_EDAC_PPC4XX)		+= ppc4xx_edac.o
 obj-$(CONFIG_EDAC_AMD8111)		+= amd8111_edac.o
 obj-$(CONFIG_EDAC_AMD8131)		+= amd8131_edac.o
 
+imh_edac-y				:= imh_base.o
+obj-$(CONFIG_EDAC_IMH)			+= imh_edac.o skx_edac_common.o
+
 obj-$(CONFIG_EDAC_HIGHBANK_MC)		+= highbank_mc_edac.o
 obj-$(CONFIG_EDAC_HIGHBANK_L2)		+= highbank_l2_edac.o
 
diff --git a/drivers/edac/imh_base.c b/drivers/edac/imh_base.c
new file mode 100644
index 0000000000000..2be27be783907
--- /dev/null
+++ b/drivers/edac/imh_base.c
@@ -0,0 +1,562 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for Intel(R) servers with Integrated Memory/IO Hub-based memory controller.
+ * Copyright (c) 2025, Intel Corporation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <asm/cpu_device_id.h>
+#include <asm/intel-family.h>
+#include <asm/mce.h>
+#include <asm/cpu.h>
+#include "edac_module.h"
+#include "skx_common.h"
+
+#define IMH_REVISION	"v0.0.1"
+#define EDAC_MOD_STR	"imh_edac"
+
+/* Debug macros */
+#define imh_printk(level, fmt, arg...)	\
+	edac_printk(level, "imh", fmt, ##arg)
+
+/* Configuration Agent(Ubox) */
+#define MMIO_BASE_H(reg)		(((u64)GET_BITFIELD(reg, 0, 29)) << 23)
+#define SOCKET_ID(reg)			GET_BITFIELD(reg, 0, 3)
+
+/* PUNIT */
+#define DDR_IMC_BITMAP(reg)		GET_BITFIELD(reg, 23, 30)
+
+/* Memory Controller */
+#define ECC_ENABLED(reg)		GET_BITFIELD(reg, 2, 2)
+#define DIMM_POPULATED(reg)		GET_BITFIELD(reg, 15, 15)
+
+/* System Cache Agent(SCA) */
+#define TOLM(reg)			(((u64)GET_BITFIELD(reg, 16, 31)) << 16)
+#define TOHM(reg)			(((u64)GET_BITFIELD(reg, 16, 51)) << 16)
+
+/**
+ * struct local_reg - A register as described in the local package view.
+ *
+ * @pkg: (input)	The package where the register is located.
+ * @pbase: (input)	The IP MMIO base physical address in the local package view.
+ * @size: (input)	The IP MMIO size.
+ * @offset: (input)	The register offset from the IP MMIO base @pbase.
+ * @width: (input)	The register width in byte.
+ * @vbase: (internal)	The IP MMIO base virtual address.
+ * @val: (output)	The register value.
+ */
+struct local_reg {
+	int pkg;
+	u64 pbase;
+	u32 size;
+	u32 offset;
+	u8  width;
+	void __iomem *vbase;
+	u64 val;
+};
+
+#define DEFINE_LOCAL_REG(name, cfg, package, north, ip_name, ip_idx, reg_name)	\
+	struct local_reg name = {						\
+		.pkg	= package,						\
+		.pbase	= (north ? (cfg)->mmio_base_l_north :			\
+			  (cfg)->mmio_base_l_south) +				\
+			  (cfg)->ip_name##_base +				\
+			  (cfg)->ip_name##_size * (ip_idx),			\
+		.size	= (cfg)->ip_name##_size,				\
+		.offset	= (cfg)->ip_name##_reg_##reg_name##_offset,		\
+		.width	= (cfg)->ip_name##_reg_##reg_name##_width,		\
+	}
+
+static u64 readx(void __iomem *addr, u8 width)
+{
+	switch (width) {
+	case 1:
+		return readb(addr);
+	case 2:
+		return readw(addr);
+	case 4:
+		return readl(addr);
+	case 8:
+		return readq(addr);
+	default:
+		imh_printk(KERN_ERR, "Invalid reg 0x%p width %d\n", addr, width);
+		return 0;
+	}
+}
+
+static void __read_local_reg(void *reg)
+{
+	struct local_reg *r = (struct local_reg *)reg;
+
+	r->val = readx(r->vbase + r->offset, r->width);
+}
+
+/* Read a local-view register. */
+static bool read_local_reg(struct local_reg *reg)
+{
+	int cpu;
+
+	/* Get the target CPU in the package @reg->pkg. */
+	for_each_online_cpu(cpu) {
+		if (reg->pkg == topology_physical_package_id(cpu))
+			break;
+	}
+
+	if (cpu >= nr_cpu_ids)
+		return false;
+
+	reg->vbase = ioremap(reg->pbase, reg->size);
+	if (!reg->vbase) {
+		imh_printk(KERN_ERR, "Failed to ioremap 0x%llx\n", reg->pbase);
+		return false;
+	}
+
+	/* Get the target CPU to read the register. */
+	smp_call_function_single(cpu, __read_local_reg, reg, 1);
+	iounmap(reg->vbase);
+
+	return true;
+}
+
+/* Get the bitmap of memory controller instances in package @pkg. */
+static u32 get_imc_bitmap(struct res_config *cfg, int pkg, bool north)
+{
+	DEFINE_LOCAL_REG(reg, cfg, pkg, north, pcu, 0, capid3);
+
+	if (!read_local_reg(&reg))
+		return 0;
+
+	edac_dbg(2, "Pkg%d %s mc instances bitmap 0x%llx (reg 0x%llx)\n",
+		 pkg, north ? "north" : "south",
+		 DDR_IMC_BITMAP(reg.val), reg.val);
+
+	return DDR_IMC_BITMAP(reg.val);
+}
+
+static void imc_release(struct device *dev)
+{
+	edac_dbg(2, "imc device %s released\n", dev_name(dev));
+	kfree(dev);
+}
+
+static int __get_ddr_munits(struct res_config *cfg, struct skx_dev *d,
+			    bool north, int lmc)
+{
+	unsigned long size = cfg->ddr_chan_mmio_sz * cfg->ddr_chan_num;
+	unsigned long bitmap = get_imc_bitmap(cfg, d->pkg, north);
+	void __iomem *mbase;
+	struct device *dev;
+	int i, rc, pmc;
+	u64 base;
+
+	for_each_set_bit(i, &bitmap, sizeof(bitmap) * 8) {
+		base  = north ? d->mmio_base_h_north : d->mmio_base_h_south;
+		base += cfg->ddr_imc_base + size * i;
+
+		edac_dbg(2, "Pkg%d mc%d mmio base 0x%llx size 0x%lx\n",
+			 d->pkg, lmc, base, size);
+
+		/* Set up the imc MMIO. */
+		mbase = ioremap(base, size);
+		if (!mbase) {
+			imh_printk(KERN_ERR, "Failed to ioremap 0x%llx\n", base);
+			return -ENOMEM;
+		}
+
+		d->imc[lmc].mbase = mbase;
+		d->imc[lmc].lmc = lmc;
+
+		/* Create the imc device instance. */
+		dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+		if (!dev)
+			return -ENOMEM;
+
+		dev->release = imc_release;
+		device_initialize(dev);
+		rc = dev_set_name(dev, "0x%llx", base);
+		if (rc) {
+			imh_printk(KERN_ERR, "Failed to set dev name\n");
+			put_device(dev);
+			return rc;
+		}
+
+		d->imc[lmc].dev = dev;
+
+		/* Set up the imc index mapping. */
+		pmc = north ? i : 8 + i;
+		skx_set_mc_mapping(d, pmc, lmc);
+
+		lmc++;
+	}
+
+	return lmc;
+}
+
+static bool get_ddr_munits(struct res_config *cfg, struct skx_dev *d)
+{
+	int lmc = __get_ddr_munits(cfg, d, true, 0);
+
+	if (lmc < 0)
+		return false;
+
+	lmc = __get_ddr_munits(cfg, d, false, lmc);
+	if (lmc <= 0)
+		return false;
+
+	return true;
+}
+
+static bool get_socket_id(struct res_config *cfg, struct skx_dev *d)
+{
+	DEFINE_LOCAL_REG(reg, cfg, d->pkg, true, ubox, 0, socket_id);
+	u8 src_id;
+	int i;
+
+	if (!read_local_reg(&reg))
+		return false;
+
+	src_id = SOCKET_ID(reg.val);
+	edac_dbg(2, "socket id 0x%x (reg 0x%llx)\n", src_id, reg.val);
+
+	for (i = 0; i < cfg->ddr_imc_num; i++)
+		d->imc[i].src_id   = src_id;
+
+	return true;
+}
+
+/* Get TOLM (Top Of Low Memory) and TOHM (Top Of High Memory) parameters. */
+static bool imh_get_tolm_tohm(struct res_config *cfg, u64 *tolm, u64 *tohm)
+{
+	DEFINE_LOCAL_REG(reg, cfg, 0, true, sca, 0, tolm);
+
+	if (!read_local_reg(&reg))
+		return false;
+
+	*tolm = TOLM(reg.val);
+	edac_dbg(2, "tolm 0x%llx (reg 0x%llx)\n", *tolm, reg.val);
+
+	DEFINE_LOCAL_REG(reg2, cfg, 0, true, sca, 0, tohm);
+
+	if (!read_local_reg(&reg2))
+		return false;
+
+	*tohm = TOHM(reg2.val);
+	edac_dbg(2, "tohm 0x%llx (reg 0x%llx)\n", *tohm, reg2.val);
+
+	return true;
+}
+
+/* Get the system-view MMIO_BASE_H for {north,south}-IMH. */
+static int imh_get_all_mmio_base_h(struct res_config *cfg, struct list_head *edac_list)
+{
+	int i, n = topology_max_packages(), imc_num = cfg->ddr_imc_num + cfg->hbm_imc_num;
+	struct skx_dev *d;
+
+	for (i = 0; i < n; i++) {
+		d = kzalloc(struct_size(d, imc, imc_num), GFP_KERNEL);
+		if (!d)
+			return -ENOMEM;
+
+		DEFINE_LOCAL_REG(reg, cfg, i, true, ubox, 0, mmio_base);
+
+		/* Get MMIO_BASE_H for the north-IMH. */
+		if (!read_local_reg(&reg) || !reg.val) {
+			kfree(d);
+			imh_printk(KERN_ERR, "Pkg%d has no north mmio_base_h\n", i);
+			return -ENODEV;
+		}
+
+		d->mmio_base_h_north = MMIO_BASE_H(reg.val);
+		edac_dbg(2, "Pkg%d north mmio_base_h 0x%llx (reg 0x%llx)\n",
+			 i, d->mmio_base_h_north, reg.val);
+
+		/* Get MMIO_BASE_H for the south-IMH (optional). */
+		DEFINE_LOCAL_REG(reg2, cfg, i, false, ubox, 0, mmio_base);
+
+		if (read_local_reg(&reg2)) {
+			d->mmio_base_h_south = MMIO_BASE_H(reg2.val);
+			edac_dbg(2, "Pkg%d south mmio_base_h 0x%llx (reg 0x%llx)\n",
+				 i, d->mmio_base_h_south, reg2.val);
+		}
+
+		d->pkg = i;
+		d->num_imc = imc_num;
+		skx_init_mc_mapping(d);
+		list_add_tail(&d->list, edac_list);
+	}
+
+	return 0;
+}
+
+/* Get the number of per-package memory controllers. */
+static int imh_get_imc_num(struct res_config *cfg)
+{
+	int imc_num = hweight32(get_imc_bitmap(cfg, 0, true)) +
+		      hweight32(get_imc_bitmap(cfg, 0, false));
+
+	if (!imc_num) {
+		imh_printk(KERN_ERR, "Invalid mc number\n");
+		return -ENODEV;
+	}
+
+	if (cfg->ddr_imc_num != imc_num) {
+		/*
+		 * Update the configuration data to reflect the number of
+		 * present DDR memory controllers.
+		 */
+		cfg->ddr_imc_num = imc_num;
+		edac_dbg(2, "Set ddr mc number %d\n", imc_num);
+	}
+
+	return 0;
+}
+
+/* Get all memory controllers' parameters. */
+static int imh_get_munits(struct res_config *cfg, struct list_head *edac_list)
+{
+	struct skx_imc *imc;
+	struct skx_dev *d;
+	u8 mc = 0;
+	int i;
+
+	list_for_each_entry(d, edac_list, list) {
+		if (!get_ddr_munits(cfg, d)) {
+			imh_printk(KERN_ERR, "No mc found\n");
+			return -ENODEV;
+		}
+
+		if (!get_socket_id(cfg, d)) {
+			imh_printk(KERN_ERR, "Failed to get socket id\n");
+			return -ENODEV;
+		}
+
+		for (i = 0; i < cfg->ddr_imc_num; i++) {
+			imc = &d->imc[i];
+			if (!imc->mbase)
+				continue;
+
+			imc->chan_mmio_sz = cfg->ddr_chan_mmio_sz;
+			imc->num_channels = cfg->ddr_chan_num;
+			imc->num_dimms    = cfg->ddr_dimm_num;
+			imc->mc		  = mc++;
+		}
+	}
+
+	return 0;
+}
+
+/* Helpers to read memory controller registers */
+static u64 read_imc_reg(struct skx_imc *imc, int chan, u32 offset, u8 width)
+{
+	return readx(imc->mbase + imc->chan_mmio_sz * chan + offset, width);
+}
+
+static u32 read_imc_mcmtr(struct res_config *cfg, struct skx_imc *imc, int chan)
+{
+	return (u32)read_imc_reg(imc, chan, cfg->ddr_reg_mcmtr_offset, cfg->ddr_reg_mcmtr_width);
+}
+
+static u32 read_imc_dimmmtr(struct res_config *cfg, struct skx_imc *imc, int chan, int dimm)
+{
+	return (u32)read_imc_reg(imc, chan, cfg->ddr_reg_dimmmtr_offset +
+				 cfg->ddr_reg_dimmmtr_width * dimm,
+				 cfg->ddr_reg_dimmmtr_width);
+}
+
+static bool ecc_enabled(u32 mcmtr)
+{
+	return (bool)ECC_ENABLED(mcmtr);
+}
+
+static bool dimm_populated(u32 dimmmtr)
+{
+	return (bool)DIMM_POPULATED(dimmmtr);
+}
+
+/* Get each DIMM's configurations of the memory controller @mci. */
+static int imh_get_dimm_config(struct mem_ctl_info *mci, struct res_config *cfg)
+{
+	struct skx_pvt *pvt = mci->pvt_info;
+	struct skx_imc *imc = pvt->imc;
+	struct dimm_info *dimm;
+	u32 mcmtr, dimmmtr;
+	int i, j, ndimms;
+
+	for (i = 0; i < imc->num_channels; i++) {
+		if (!imc->mbase)
+			continue;
+
+		mcmtr = read_imc_mcmtr(cfg, imc, i);
+
+		for (ndimms = 0, j = 0; j < imc->num_dimms; j++) {
+			dimmmtr = read_imc_dimmmtr(cfg, imc, i, j);
+			edac_dbg(1, "mcmtr 0x%x dimmmtr 0x%x (mc%d ch%d dimm%d)\n",
+				 mcmtr, dimmmtr, imc->mc, i, j);
+
+			if (!dimm_populated(dimmmtr))
+				continue;
+
+			dimm = edac_get_dimm(mci, i, j, 0);
+			ndimms += skx_get_dimm_info(dimmmtr, 0, 0, dimm,
+						    imc, i, j, cfg);
+		}
+
+		if (ndimms && !ecc_enabled(mcmtr)) {
+			imh_printk(KERN_ERR, "ECC is disabled on mc%d ch%d\n",
+				   imc->mc, i);
+			return -ENODEV;
+		}
+	}
+
+	return 0;
+}
+
+/* Register all memory controllers to the EDAC core. */
+static int imh_register_mci(struct res_config *cfg, struct list_head *edac_list)
+{
+	struct skx_imc *imc;
+	struct skx_dev *d;
+	int i, rc;
+
+	list_for_each_entry(d, edac_list, list) {
+		for (i = 0; i < cfg->ddr_imc_num; i++) {
+			imc = &d->imc[i];
+			if (!imc->mbase)
+				continue;
+
+			rc = skx_register_mci(imc, imc->dev,
+					      dev_name(imc->dev),
+					      "Intel IMH-based Socket",
+					      EDAC_MOD_STR,
+					      imh_get_dimm_config, cfg);
+			if (rc)
+				return rc;
+		}
+	}
+
+	return 0;
+}
+
+static struct res_config dmr_cfg = {
+	.type				= DMR,
+	.support_ddr5			= true,
+	.mmio_base_l_north		= 0xf6800000,
+	.mmio_base_l_south		= 0xf6000000,
+	.ddr_chan_num			= 1,
+	.ddr_dimm_num			= 2,
+	.ddr_imc_base			= 0x39b000,
+	.ddr_chan_mmio_sz		= 0x8000,
+	.ddr_reg_mcmtr_offset		= 0x360,
+	.ddr_reg_mcmtr_width		= 4,
+	.ddr_reg_dimmmtr_offset		= 0x370,
+	.ddr_reg_dimmmtr_width		= 4,
+	.ubox_base			= 0x0,
+	.ubox_size			= 0x2000,
+	.ubox_reg_mmio_base_offset	= 0x580,
+	.ubox_reg_mmio_base_width	= 4,
+	.ubox_reg_socket_id_offset	= 0x1080,
+	.ubox_reg_socket_id_width	= 4,
+	.pcu_base			= 0x3000,
+	.pcu_size			= 0x10000,
+	.pcu_reg_capid3_offset		= 0x290,
+	.pcu_reg_capid3_width		= 4,
+	.sca_base			= 0x24c000,
+	.sca_size			= 0x2500,
+	.sca_reg_tolm_offset		= 0x2100,
+	.sca_reg_tolm_width		= 8,
+	.sca_reg_tohm_offset		= 0x2108,
+	.sca_reg_tohm_width		= 8,
+};
+
+static const struct x86_cpu_id imh_cpuids[] = {
+	X86_MATCH_VFM(INTEL_DIAMONDRAPIDS_X, &dmr_cfg),
+	{}
+};
+MODULE_DEVICE_TABLE(x86cpu, imh_cpuids);
+
+static struct notifier_block imh_mce_dec = {
+	.notifier_call	= skx_mce_check_error,
+	.priority	= MCE_PRIO_EDAC,
+};
+
+static int __init imh_init(void)
+{
+	const struct x86_cpu_id *id;
+	struct list_head *edac_list;
+	struct res_config *cfg;
+	const char *owner;
+	u64 tolm, tohm;
+	int rc;
+
+	edac_dbg(2, "\n");
+
+	if (ghes_get_devices())
+		return -EBUSY;
+
+	owner = edac_get_owner();
+	if (owner && strncmp(owner, EDAC_MOD_STR, sizeof(EDAC_MOD_STR)))
+		return -EBUSY;
+
+	if (cpu_feature_enabled(X86_FEATURE_HYPERVISOR))
+		return -ENODEV;
+
+	id = x86_match_cpu(imh_cpuids);
+	if (!id)
+		return -ENODEV;
+	cfg = (struct res_config *)id->driver_data;
+	skx_set_res_cfg(cfg);
+
+	if (!imh_get_tolm_tohm(cfg, &tolm, &tohm))
+		return -ENODEV;
+
+	skx_set_hi_lo(tolm, tohm);
+
+	rc = imh_get_imc_num(cfg);
+	if (rc < 0)
+		goto fail;
+
+	edac_list = skx_get_edac_list();
+
+	rc = imh_get_all_mmio_base_h(cfg, edac_list);
+	if (rc)
+		goto fail;
+
+	rc = imh_get_munits(cfg, edac_list);
+	if (rc)
+		goto fail;
+
+	rc = imh_register_mci(cfg, edac_list);
+	if (rc)
+		goto fail;
+
+	rc = skx_adxl_get();
+	if (rc)
+		goto fail;
+
+	opstate_init();
+	mce_register_decode_chain(&imh_mce_dec);
+
+	imh_printk(KERN_INFO, "%s\n", IMH_REVISION);
+
+	return 0;
+fail:
+	skx_remove();
+	return rc;
+}
+
+static void __exit imh_exit(void)
+{
+	edac_dbg(2, "\n");
+
+	mce_unregister_decode_chain(&imh_mce_dec);
+	skx_adxl_put();
+	skx_remove();
+}
+
+module_init(imh_init);
+module_exit(imh_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Qiuxu Zhuo");
+MODULE_DESCRIPTION("MC Driver for Intel servers using IMH-based memory controller");
diff --git a/drivers/edac/skx_common.c b/drivers/edac/skx_common.c
index 38603509efab0..3f2b6c4e16e6b 100644
--- a/drivers/edac/skx_common.c
+++ b/drivers/edac/skx_common.c
@@ -125,7 +125,7 @@ void skx_adxl_put(void)
 }
 EXPORT_SYMBOL_GPL(skx_adxl_put);
 
-static void skx_init_mc_mapping(struct skx_dev *d)
+void skx_init_mc_mapping(struct skx_dev *d)
 {
 	/*
 	 * By default, the BIOS presents all memory controllers within each
@@ -136,6 +136,7 @@ static void skx_init_mc_mapping(struct skx_dev *d)
 	for (int i = 0; i < d->num_imc; i++)
 		d->imc[i].mc_mapping = i;
 }
+EXPORT_SYMBOL_GPL(skx_init_mc_mapping);
 
 void skx_set_mc_mapping(struct skx_dev *d, u8 pmc, u8 lmc)
 {
@@ -827,6 +828,9 @@ void skx_remove(void)
 			if (d->imc[i].mbase)
 				iounmap(d->imc[i].mbase);
 
+			if (d->imc[i].dev)
+				put_device(d->imc[i].dev);
+
 			for (j = 0; j < d->imc[i].num_channels; j++) {
 				if (d->imc[i].chan[j].cdev)
 					pci_dev_put(d->imc[i].chan[j].cdev);
@@ -850,7 +854,7 @@ EXPORT_SYMBOL_GPL(skx_remove);
 /*
  * Debug feature.
  * Exercise the address decode logic by writing an address to
- * /sys/kernel/debug/edac/{skx,i10nm}_test/addr.
+ * /sys/kernel/debug/edac/{skx,i10nm,imh}_test/addr.
  */
 static struct dentry *skx_test;
 
diff --git a/drivers/edac/skx_common.h b/drivers/edac/skx_common.h
index 93f50ab4153f9..b970e8f4680d8 100644
--- a/drivers/edac/skx_common.h
+++ b/drivers/edac/skx_common.h
@@ -126,20 +126,33 @@ struct reg_rrl {
  * memory controllers on the die.
  */
 struct skx_dev {
-	struct list_head list;
+	/* {skx,i10nm}_edac */
 	u8 bus[4];
 	int seg;
 	struct pci_dev *sad_all;
 	struct pci_dev *util_all;
-	struct pci_dev *uracu; /* for i10nm CPU */
-	struct pci_dev *pcu_cr3; /* for HBM memory detection */
+	struct pci_dev *uracu;
+	struct pci_dev *pcu_cr3;
 	u32 mcroute;
+
+	/* imh_edac */
+	/* System-view MMIO base physical addresses. */
+	u64 mmio_base_h_north;
+	u64 mmio_base_h_south;
+	int pkg;
+
 	int num_imc;
+	struct list_head list;
 	struct skx_imc {
+		/* i10nm_edac */
+		struct pci_dev *mdev;
+
+		/* imh_edac */
+		struct device *dev;
+
 		struct mem_ctl_info *mci;
-		struct pci_dev *mdev; /* for i10nm CPU */
-		void __iomem *mbase;  /* for i10nm CPU */
-		int chan_mmio_sz;     /* for i10nm CPU */
+		void __iomem *mbase;
+		int chan_mmio_sz;
 		int num_channels; /* channels per memory controller */
 		int num_dimms; /* dimms per channel */
 		bool hbm_mc;
@@ -183,7 +196,8 @@ enum type {
 	SKX,
 	I10NM,
 	SPR,
-	GNR
+	GNR,
+	DMR,
 };
 
 enum {
@@ -242,10 +256,6 @@ struct pci_bdf {
 
 struct res_config {
 	enum type type;
-	/* Configuration agent device ID */
-	unsigned int decs_did;
-	/* Default bus number configuration register offset */
-	int busno_cfg_offset;
 	/* DDR memory controllers per socket */
 	int ddr_imc_num;
 	/* DDR channels per DDR memory controller */
@@ -263,23 +273,53 @@ struct res_config {
 	/* Per HBM channel memory-mapped I/O size */
 	int hbm_chan_mmio_sz;
 	bool support_ddr5;
-	/* SAD device BDF */
-	struct pci_bdf sad_all_bdf;
-	/* PCU device BDF */
-	struct pci_bdf pcu_cr3_bdf;
-	/* UTIL device BDF */
-	struct pci_bdf util_all_bdf;
-	/* URACU device BDF */
-	struct pci_bdf uracu_bdf;
-	/* DDR mdev device BDF */
-	struct pci_bdf ddr_mdev_bdf;
-	/* HBM mdev device BDF */
-	struct pci_bdf hbm_mdev_bdf;
-	int sad_all_offset;
 	/* RRL register sets per DDR channel */
 	struct reg_rrl *reg_rrl_ddr;
 	/* RRL register sets per HBM channel */
 	struct reg_rrl *reg_rrl_hbm[2];
+	union {
+		/* {skx,i10nm}_edac */
+		struct {
+			/* Configuration agent device ID */
+			unsigned int decs_did;
+			/* Default bus number configuration register offset */
+			int busno_cfg_offset;
+			struct pci_bdf sad_all_bdf;
+			struct pci_bdf pcu_cr3_bdf;
+			struct pci_bdf util_all_bdf;
+			struct pci_bdf uracu_bdf;
+			struct pci_bdf ddr_mdev_bdf;
+			struct pci_bdf hbm_mdev_bdf;
+			int sad_all_offset;
+		};
+		/* imh_edac */
+		struct {
+			/* MMIO base physical address in local package view */
+			u64 mmio_base_l_north;
+			u64 mmio_base_l_south;
+			u64 ddr_imc_base;
+			u64 ddr_reg_mcmtr_offset;
+			u8  ddr_reg_mcmtr_width;
+			u64 ddr_reg_dimmmtr_offset;
+			u8  ddr_reg_dimmmtr_width;
+			u64 ubox_base;
+			u32 ubox_size;
+			u32 ubox_reg_mmio_base_offset;
+			u8  ubox_reg_mmio_base_width;
+			u32 ubox_reg_socket_id_offset;
+			u8  ubox_reg_socket_id_width;
+			u64 pcu_base;
+			u32 pcu_size;
+			u32 pcu_reg_capid3_offset;
+			u8  pcu_reg_capid3_width;
+			u64 sca_base;
+			u32 sca_size;
+			u32 sca_reg_tolm_offset;
+			u8  sca_reg_tolm_width;
+			u32 sca_reg_tohm_offset;
+			u8  sca_reg_tohm_width;
+		};
+	};
 };
 
 typedef int (*get_dimm_config_f)(struct mem_ctl_info *mci,
@@ -292,6 +332,7 @@ void skx_adxl_put(void);
 void skx_set_decode(skx_decode_f decode, skx_show_retry_log_f show_retry_log);
 void skx_set_mem_cfg(bool mem_cfg_2lm);
 void skx_set_res_cfg(struct res_config *cfg);
+void skx_init_mc_mapping(struct skx_dev *d);
 void skx_set_mc_mapping(struct skx_dev *d, u8 pmc, u8 lmc);
 
 int skx_get_src_id(struct skx_dev *d, int off, u8 *id);

From 7f44b87483914a2809befd53630c91d4cbc4c42e Mon Sep 17 00:00:00 2001
From: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Date: Wed, 19 Nov 2025 12:11:40 -0800
Subject: [PATCH 09/11] EDAC/skx_common: Extend the maximum number of DRAM chip
 row bits

commit 39abdcbdad597b1ac3dabd44a757de91b87c683a upstream.

The allowed maximum number of row bits for DRAM chips in the Diamond
Rapids server processor is up to 19. Extend the current maximum row
bits from 18 to 19.

Intel-SIG: commit 39abdcbdad59 EDAC/skx_common: Extend the maximum number of DRAM chip row bits
Backport EDAC for DMR

Tested-by: Yi Lai <yi1.lai@intel.com>
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://patch.msgid.link/20251119134132.2389472-6-qiuxu.zhuo@intel.com
[ Zhang Rui: amend change log ]
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
---
 drivers/edac/skx_common.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/edac/skx_common.c b/drivers/edac/skx_common.c
index 3f2b6c4e16e6b..4ed4f5a465e08 100644
--- a/drivers/edac/skx_common.c
+++ b/drivers/edac/skx_common.c
@@ -452,7 +452,7 @@ static int skx_get_dimm_attr(u32 reg, int lobit, int hibit, int add,
 }
 
 #define numrank(reg)	skx_get_dimm_attr(reg, 12, 13, 0, 0, 2, "ranks")
-#define numrow(reg)	skx_get_dimm_attr(reg, 2, 4, 12, 1, 6, "rows")
+#define numrow(reg)	skx_get_dimm_attr(reg, 2, 4, 12, 1, 7, "rows")
 #define numcol(reg)	skx_get_dimm_attr(reg, 0, 1, 10, 0, 2, "cols")
 
 int skx_get_dimm_info(u32 mtr, u32 mcmtr, u32 amap, struct dimm_info *dimm,

From cc44e58bb48bf4f334b30e3635da05a03566a860 Mon Sep 17 00:00:00 2001
From: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Date: Wed, 19 Nov 2025 12:11:40 -0800
Subject: [PATCH 10/11] EDAC/{skx_comm,imh}: Detect 2-level memory
 configuration

commit f619613f3058dee38f50b116ec774c5295c8b08b upstream.

Detect 2-level memory configurations and notify the 'skx_common' library
to enable ADXL 2-level memory error decoding.

Intel-SIG: commit f619613f3058 EDAC/{skx_comm,imh}: Detect 2-level memory configuration
Backport EDAC for DMR

Tested-by: Yi Lai <yi1.lai@intel.com>
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://patch.msgid.link/20251119134132.2389472-7-qiuxu.zhuo@intel.com
[ Zhang Rui: amend change log ]
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
---
 drivers/edac/imh_base.c   | 38 ++++++++++++++++++++++++++++++++++++++
 drivers/edac/skx_common.h |  4 ++++
 2 files changed, 42 insertions(+)

diff --git a/drivers/edac/imh_base.c b/drivers/edac/imh_base.c
index 2be27be783907..2b0db6321da0a 100644
--- a/drivers/edac/imh_base.c
+++ b/drivers/edac/imh_base.c
@@ -35,6 +35,9 @@
 #define TOLM(reg)			(((u64)GET_BITFIELD(reg, 16, 31)) << 16)
 #define TOHM(reg)			(((u64)GET_BITFIELD(reg, 16, 51)) << 16)
 
+/* Home Agent (HA) */
+#define NMCACHING(reg)			GET_BITFIELD(reg, 8, 8)
+
 /**
  * struct local_reg - A register as described in the local package view.
  *
@@ -346,6 +349,35 @@ static int imh_get_munits(struct res_config *cfg, struct list_head *edac_list)
 	return 0;
 }
 
+static bool check_2lm_enabled(struct res_config *cfg, struct skx_dev *d, int ha_idx)
+{
+	DEFINE_LOCAL_REG(reg, cfg, d->pkg, true, ha, ha_idx, mode);
+
+	if (!read_local_reg(&reg))
+		return false;
+
+	if (!NMCACHING(reg.val))
+		return false;
+
+	edac_dbg(2, "2-level memory configuration (reg 0x%llx, ha idx %d)\n", reg.val, ha_idx);
+	return true;
+}
+
+/* Check whether the system has a 2-level memory configuration. */
+static bool imh_2lm_enabled(struct res_config *cfg, struct list_head *head)
+{
+	struct skx_dev *d;
+	int i;
+
+	list_for_each_entry(d, head, list) {
+		for (i = 0; i < cfg->ddr_imc_num; i++)
+			if (check_2lm_enabled(cfg, d, i))
+				return true;
+	}
+
+	return false;
+}
+
 /* Helpers to read memory controller registers */
 static u64 read_imc_reg(struct skx_imc *imc, int chan, u32 offset, u8 width)
 {
@@ -467,6 +499,10 @@ static struct res_config dmr_cfg = {
 	.sca_reg_tolm_width		= 8,
 	.sca_reg_tohm_offset		= 0x2108,
 	.sca_reg_tohm_width		= 8,
+	.ha_base			= 0x3eb000,
+	.ha_size			= 0x1000,
+	.ha_reg_mode_offset		= 0x4a0,
+	.ha_reg_mode_width		= 4,
 };
 
 static const struct x86_cpu_id imh_cpuids[] = {
@@ -526,6 +562,8 @@ static int __init imh_init(void)
 	if (rc)
 		goto fail;
 
+	skx_set_mem_cfg(imh_2lm_enabled(cfg, edac_list));
+
 	rc = imh_register_mci(cfg, edac_list);
 	if (rc)
 		goto fail;
diff --git a/drivers/edac/skx_common.h b/drivers/edac/skx_common.h
index b970e8f4680d8..0ca6c9cd46a9d 100644
--- a/drivers/edac/skx_common.h
+++ b/drivers/edac/skx_common.h
@@ -318,6 +318,10 @@ struct res_config {
 			u8  sca_reg_tolm_width;
 			u32 sca_reg_tohm_offset;
 			u8  sca_reg_tohm_width;
+			u64 ha_base;
+			u32 ha_size;
+			u32 ha_reg_mode_offset;
+			u8  ha_reg_mode_width;
 		};
 	};
 };

From 7c142fc14591fbd1bd189205dbbe8a5d9a1f99c8 Mon Sep 17 00:00:00 2001
From: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Date: Wed, 19 Nov 2025 12:11:40 -0800
Subject: [PATCH 11/11] EDAC/imh: Setup 'imh_test' debugfs testing node

commit 5f40ea7f41773d996d92db8bde600199200adc11 upstream.

Setup the following debugfs testing node to enable fake memory error
address decoding tests for the imh_edac driver.

  /sys/kernel/debug/edac/imh_test/addr

Intel-SIG: commit 5f40ea7f4177 EDAC/imh: Setup 'imh_test' debugfs testing node
Backport EDAC for DMR

Tested-by: Yi Lai <yi1.lai@intel.com>
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://patch.msgid.link/20251119134132.2389472-8-qiuxu.zhuo@intel.com
[ Zhang Rui: amend change log ]
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
---
 drivers/edac/imh_base.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/edac/imh_base.c b/drivers/edac/imh_base.c
index 2b0db6321da0a..4348b3883b457 100644
--- a/drivers/edac/imh_base.c
+++ b/drivers/edac/imh_base.c
@@ -574,6 +574,7 @@ static int __init imh_init(void)
 
 	opstate_init();
 	mce_register_decode_chain(&imh_mce_dec);
+	skx_setup_debug("imh_test");
 
 	imh_printk(KERN_INFO, "%s\n", IMH_REVISION);
 
@@ -587,6 +588,7 @@ static void __exit imh_exit(void)
 {
 	edac_dbg(2, "\n");
 
+	skx_teardown_debug();
 	mce_unregister_decode_chain(&imh_mce_dec);
 	skx_adxl_put();
 	skx_remove();