Add ACPI-based PMT discovery support for Intel PMC

index b4c9964df807..9b315334a69b 100644
@@ -381,10 +381,22 @@ int intel_pmt_dev_create(struct intel_pmt_entry *entry, struct intel_pmt_namespa
 	if (IS_ERR(entry->disc_table))
 		return PTR_ERR(entry->disc_table);
 
+	if (ns->pmt_pre_decode) {
+		ret = ns->pmt_pre_decode(intel_vsec_dev, entry);
+		if (ret)
+			return ret;
+	}
+
 	ret = ns->pmt_header_decode(entry, dev);
 	if (ret)
 		return ret;
 
+	if (ns->pmt_post_decode) {
+		ret = ns->pmt_post_decode(intel_vsec_dev, entry);
+		if (ret)
+			return ret;
+	}
+
 	ret = intel_pmt_populate_entry(entry, intel_vsec_dev, disc_res);
 	if (ret)
 		return ret;

index 1ae56a5baad2..ff39014b208c 100644
@@ -62,6 +62,10 @@ struct intel_pmt_namespace {
 	struct xarray *xa;
 	int (*pmt_header_decode)(struct intel_pmt_entry *entry,
 				 struct device *dev);
+	int (*pmt_pre_decode)(struct intel_vsec_device *ivdev,
+			      struct intel_pmt_entry *entry);
+	int (*pmt_post_decode)(struct intel_vsec_device *ivdev,
+			       struct intel_pmt_entry *entry);
 	int (*pmt_add_endpoint)(struct intel_vsec_device *ivdev,
 				struct intel_pmt_entry *entry);
 };

index b0393c9c5b4b..f936daf99e4d 100644
@@ -496,11 +496,9 @@ static const struct crashlog_info *select_crashlog_info(u32 type, u32 version)
 	return &crashlog_type1_ver2;
 }
 
-static int pmt_crashlog_header_decode(struct intel_pmt_entry *entry,
-				      struct device *dev)
+static int pmt_crashlog_pre_decode(struct intel_vsec_device *ivdev,
+				   struct intel_pmt_entry *entry)
 {
-	void __iomem *disc_table = entry->disc_table;
-	struct intel_pmt_header *header = &entry->header;
 	struct crashlog_entry *crashlog;
 	u32 version;
 	u32 type;

@@ -513,6 +511,16 @@ static int pmt_crashlog_header_decode(struct intel_pmt_entry *entry,
 	mutex_init(&crashlog->control_mutex);
 
 	crashlog->info = select_crashlog_info(type, version);
+	entry->attr_grp = crashlog->info->attr_grp;
+
+	return 0;
+}
+
+static int pmt_crashlog_header_decode(struct intel_pmt_entry *entry,
+				      struct device *dev)
+{
+	void __iomem *disc_table = entry->disc_table;
+	struct intel_pmt_header *header = &entry->header;
 
 	header->access_type = GET_ACCESS(readl(disc_table));
 	header->guid = readl(disc_table + GUID_OFFSET);

@@ -521,8 +529,6 @@ static int pmt_crashlog_header_decode(struct intel_pmt_entry *entry,
 	/* Size is measured in DWORDS, but accessor returns bytes */
 	header->size = GET_SIZE(readl(disc_table + SIZE_OFFSET));
 
-	entry->attr_grp = crashlog->info->attr_grp;
-
 	return 0;
 }
 

@@ -530,6 +536,7 @@ static DEFINE_XARRAY_ALLOC(crashlog_array);
 static struct intel_pmt_namespace pmt_crashlog_ns = {
 	.name = "crashlog",
 	.xa = &crashlog_array,
+	.pmt_pre_decode = pmt_crashlog_pre_decode,
 	.pmt_header_decode = pmt_crashlog_header_decode,
 };
 

index ff39014b208c..8a0db0ef58c1 100644
@@ -37,6 +37,7 @@ struct intel_pmt_header {
 	u32	size;
 	u32	guid;
 	u8	access_type;
+	u8	telem_type;
 };
 
 struct intel_pmt_entry {

index bdc7c24a3678..d22f633638be 100644
@@ -58,14 +58,9 @@ struct pmt_telem_priv {
 	struct intel_pmt_entry		entry[];
 };
 
-static bool pmt_telem_region_overlaps(struct intel_pmt_entry *entry,
-				      struct device *dev)
+static bool pmt_telem_region_overlaps(struct device *dev, u32 guid, u32 type)
 {
-	u32 guid = readl(entry->disc_table + TELEM_GUID_OFFSET);
-
 	if (intel_pmt_is_early_client_hw(dev)) {
-		u32 type = TELEM_TYPE(readl(entry->disc_table));
-
 		if ((type == TELEM_TYPE_PUNIT_FIXED) ||
 		    (guid == TELEM_CLIENT_FIXED_BLOCK_GUID))
 			return true;

@@ -80,15 +75,25 @@ static int pmt_telem_header_decode(struct intel_pmt_entry *entry,
 	void __iomem *disc_table = entry->disc_table;
 	struct intel_pmt_header *header = &entry->header;
 
-	if (pmt_telem_region_overlaps(entry, dev))
-		return 1;
-
 	header->access_type = TELEM_ACCESS(readl(disc_table));
 	header->guid = readl(disc_table + TELEM_GUID_OFFSET);
 	header->base_offset = readl(disc_table + TELEM_BASE_OFFSET);
 
 	/* Size is measured in DWORDS, but accessor returns bytes */
 	header->size = TELEM_SIZE(readl(disc_table));
+	header->telem_type = TELEM_TYPE(readl(entry->disc_table));
+
+	return 0;
+}
+
+static int pmt_telem_post_decode(struct intel_vsec_device *ivdev,
+				 struct intel_pmt_entry *entry)
+{
+	struct intel_pmt_header *header = &entry->header;
+	struct device *dev = &ivdev->auxdev.dev;
+
+	if (pmt_telem_region_overlaps(dev, header->guid, header->telem_type))
+		return 1;
 
 	/*
 	 * Some devices may expose non-functioning entries that are

@@ -131,6 +136,7 @@ static struct intel_pmt_namespace pmt_telem_ns = {
 	.name = "telem",
 	.xa = &telem_array,
 	.pmt_header_decode = pmt_telem_header_decode,
+	.pmt_post_decode = pmt_telem_post_decode,
 	.pmt_add_endpoint = pmt_telem_add_endpoint,
 };
 

index 9b315334a69b..7da8279b54f8 100644
@@ -206,11 +206,12 @@ EXPORT_SYMBOL_GPL(intel_pmt_class);
 
 static int intel_pmt_populate_entry(struct intel_pmt_entry *entry,
 				    struct intel_vsec_device *ivdev,
-				    struct resource *disc_res)
+				    int idx)
 {
 	struct pci_dev *pci_dev = to_pci_dev(ivdev->dev);
 	struct device *dev = &ivdev->auxdev.dev;
 	struct intel_pmt_header *header = &entry->header;
+	struct resource *disc_res;
 	u8 bir;
 
 	/*

@@ -235,6 +236,7 @@ static int intel_pmt_populate_entry(struct intel_pmt_entry *entry,
 		 * For access_type LOCAL, the base address is as follows:
 		 * base address = end of discovery region + base offset
 		 */
+		disc_res = &ivdev->resource[idx];
 		entry->base_addr = disc_res->end + 1 + header->base_offset;
 
 		/*

@@ -397,7 +399,7 @@ int intel_pmt_dev_create(struct intel_pmt_entry *entry, struct intel_pmt_namespa
 			return ret;
 	}
 
-	ret = intel_pmt_populate_entry(entry, intel_vsec_dev, disc_res);
+	ret = intel_pmt_populate_entry(entry, intel_vsec_dev, idx);
 	if (ret)
 		return ret;
 

index 7da8279b54f8..8d27f59d5bff 100644
@@ -12,6 +12,7 @@
 #include <linux/log2.h>
 #include <linux/intel_vsec.h>
 #include <linux/io-64-nonatomic-lo-hi.h>
+#include <linux/minmax.h>
 #include <linux/module.h>
 #include <linux/mm.h>
 #include <linux/pci.h>

@@ -383,6 +384,16 @@ int intel_pmt_dev_create(struct intel_pmt_entry *entry, struct intel_pmt_namespa
 	if (IS_ERR(entry->disc_table))
 		return PTR_ERR(entry->disc_table);
 
+	/*
+	 * The mapped discovery resource may be smaller than disc_header (its
+	 * size is the namespace's DVSEC entry_size in dwords, which can be
+	 * less than 4). Cap the copy to the actual resource size to avoid
+	 * reading past the mapped region; any unread dwords stay zero from
+	 * the zero-initialized allocation of the containing struct.
+	 */
+	memcpy_fromio(entry->disc_header, entry->disc_table,
+		      min(sizeof(entry->disc_header), resource_size(disc_res)));
+
 	if (ns->pmt_pre_decode) {
 		ret = ns->pmt_pre_decode(intel_vsec_dev, entry);
 		if (ret)

index 8a0db0ef58c1..84202fc7920c 100644
@@ -44,6 +44,7 @@ struct intel_pmt_entry {
 	struct telem_endpoint	*ep;
 	struct pci_dev		*pcidev;
 	struct intel_pmt_header	header;
+	u32			disc_header[4];
 	struct bin_attribute	pmt_bin_attr;
 	const struct attribute_group *attr_grp;
 	struct kobject		*kobj;

index d22f633638be..953f35b6daec 100644
@@ -72,16 +72,16 @@ static bool pmt_telem_region_overlaps(struct device *dev, u32 guid, u32 type)
 static int pmt_telem_header_decode(struct intel_pmt_entry *entry,
 				   struct device *dev)
 {
-	void __iomem *disc_table = entry->disc_table;
 	struct intel_pmt_header *header = &entry->header;
+	u32 *disc_header = entry->disc_header;
 
-	header->access_type = TELEM_ACCESS(readl(disc_table));
-	header->guid = readl(disc_table + TELEM_GUID_OFFSET);
-	header->base_offset = readl(disc_table + TELEM_BASE_OFFSET);
+	header->access_type = TELEM_ACCESS(disc_header[0]);
+	header->guid = disc_header[1];
+	header->base_offset = disc_header[2];
 
 	/* Size is measured in DWORDS, but accessor returns bytes */
-	header->size = TELEM_SIZE(readl(disc_table));
-	header->telem_type = TELEM_TYPE(readl(entry->disc_table));
+	header->size = TELEM_SIZE(disc_header[0]);
+	header->telem_type = TELEM_TYPE(disc_header[0]);
 
 	return 0;
 }

index 8d27f59d5bff..d0ab8e33c62a 100644
@@ -205,9 +205,9 @@ struct class intel_pmt_class = {
 };
 EXPORT_SYMBOL_GPL(intel_pmt_class);
 
-static int intel_pmt_populate_entry(struct intel_pmt_entry *entry,
-				    struct intel_vsec_device *ivdev,
-				    int idx)
+static int pmt_resolve_access_pci(struct intel_pmt_entry *entry,
+				  struct intel_vsec_device *ivdev,
+				  int idx)
 {
 	struct pci_dev *pci_dev = to_pci_dev(ivdev->dev);
 	struct device *dev = &ivdev->auxdev.dev;

@@ -287,6 +287,81 @@ static int intel_pmt_populate_entry(struct intel_pmt_entry *entry,
 	}
 
 	entry->pcidev = pci_dev;
+
+	return 0;
+}
+
+static int pmt_resolve_access_acpi(struct intel_pmt_entry *entry,
+				   struct intel_vsec_device *ivdev)
+{
+	struct pci_dev *pci_dev = NULL;
+	struct device *dev = &ivdev->auxdev.dev;
+	struct intel_pmt_header *header = &entry->header;
+	u8 bir;
+
+	if (dev_is_pci(ivdev->dev))
+		pci_dev = to_pci_dev(ivdev->dev);
+
+	/*
+	 * The base offset should always be 8 byte aligned.
+	 *
+	 * For non-local access types the lower 3 bits of base offset
+	 * contains the index of the base address register where the
+	 * telemetry can be found.
+	 */
+	bir = GET_BIR(header->base_offset);
+
+	switch (header->access_type) {
+	case ACCESS_BARID:
+		/* ACPI platform drivers use base_addr */
+		if (ivdev->base_addr) {
+			entry->base_addr = ivdev->base_addr +
+					   GET_ADDRESS(header->base_offset);
+			break;
+		}
+
+		/* If base_addr is not provided, then this is an ACPI companion device */
+		if (!pci_dev) {
+			dev_err(dev, "ACCESS_BARID requires PCI BAR resources or base_addr\n");
+			return -EINVAL;
+		}
+
+		entry->base_addr = pci_resource_start(pci_dev, bir) +
+				   GET_ADDRESS(header->base_offset);
+		break;
+	default:
+		dev_err(dev, "Unsupported access type %d for ACPI based PMT\n",
+			header->access_type);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int intel_pmt_populate_entry(struct intel_pmt_entry *entry,
+				    struct intel_vsec_device *ivdev,
+				    int idx)
+{
+	struct intel_pmt_header *header = &entry->header;
+	struct device *dev = &ivdev->auxdev.dev;
+	int ret;
+
+	switch (ivdev->src) {
+	case INTEL_VSEC_DISC_PCI:
+		ret = pmt_resolve_access_pci(entry, ivdev, idx);
+		if (ret)
+			return ret;
+		break;
+	case INTEL_VSEC_DISC_ACPI:
+		ret = pmt_resolve_access_acpi(entry, ivdev);
+		if (ret)
+			return ret;
+		break;
+	default:
+		dev_err(dev, "Unknown discovery source: %d\n", ivdev->src);
+		return -EINVAL;
+	}
+
 	entry->guid = header->guid;
 	entry->size = header->size;
 	entry->cb = ivdev->priv_data;

@@ -371,28 +446,66 @@ static int intel_pmt_dev_register(struct intel_pmt_entry *entry,
 	return ret;
 }
 
+static int pmt_get_headers(struct intel_vsec_device *ivdev, int idx,
+			   struct intel_pmt_entry *entry)
+{
+	struct device *dev = &ivdev->auxdev.dev;
+	size_t header_bytes = sizeof(entry->disc_header);
+
+	switch (ivdev->src) {
+	case INTEL_VSEC_DISC_PCI: {
+		struct resource *disc_res = &ivdev->resource[idx];
+		void __iomem *disc_table;
+
+		disc_table = devm_ioremap_resource(dev, disc_res);
+		if (IS_ERR(disc_table))
+			return PTR_ERR(disc_table);
+
+		/*
+		 * The mapped resource is sized by the namespace's DVSEC
+		 * entry_size (in dwords), which can be less than the default
+		 * size (e.g. telemetry uses entry_size = 3, 12 bytes). Cap the
+		 * copy to resource_size() to avoid reading past the mapped
+		 * region.
+		 */
+		memset(entry->disc_header, 0, header_bytes);
+		memcpy_fromio(entry->disc_header, disc_table,
+			      min(header_bytes, resource_size(disc_res)));
+
+		/* Used by crashlog driver */
+		entry->disc_table = disc_table;
+
+		return 0;
+	}
+	case INTEL_VSEC_DISC_ACPI: {
+		memcpy(entry->disc_header, &ivdev->acpi_disc[idx][0], header_bytes);
+		/*
+		 * No MMIO mapping exists on the ACPI source path; the cached
+		 * headers are the only view of the discovery record. Consumers
+		 * that dereference disc_table (e.g. crashlog) must therefore
+		 * only be wired to namespaces backed by INTEL_VSEC_DISC_PCI.
+		 */
+		entry->disc_table = NULL;
+
+		return 0;
+	}
+	default:
+		dev_err(dev, "Unknown discovery source type: %d\n", ivdev->src);
+		break;
+	}
+
+	return -EINVAL;
+}
+
 int intel_pmt_dev_create(struct intel_pmt_entry *entry, struct intel_pmt_namespace *ns,
 			 struct intel_vsec_device *intel_vsec_dev, int idx)
 {
 	struct device *dev = &intel_vsec_dev->auxdev.dev;
-	struct resource	*disc_res;
 	int ret;
 
-	disc_res = &intel_vsec_dev->resource[idx];
-
-	entry->disc_table = devm_ioremap_resource(dev, disc_res);
-	if (IS_ERR(entry->disc_table))
-		return PTR_ERR(entry->disc_table);
-
-	/*
-	 * The mapped discovery resource may be smaller than disc_header (its
-	 * size is the namespace's DVSEC entry_size in dwords, which can be
-	 * less than 4). Cap the copy to the actual resource size to avoid
-	 * reading past the mapped region; any unread dwords stay zero from
-	 * the zero-initialized allocation of the containing struct.
-	 */
-	memcpy_fromio(entry->disc_header, entry->disc_table,
-		      min(sizeof(entry->disc_header), resource_size(disc_res)));
+	ret = pmt_get_headers(intel_vsec_dev, idx, entry);
+	if (ret)
+		return ret;
 
 	if (ns->pmt_pre_decode) {
 		ret = ns->pmt_pre_decode(intel_vsec_dev, entry);

index 84202fc7920c..a0ece4fc3837 100644
@@ -44,7 +44,7 @@ struct intel_pmt_entry {
 	struct telem_endpoint	*ep;
 	struct pci_dev		*pcidev;
 	struct intel_pmt_header	header;
-	u32			disc_header[4];
+	u32			disc_header[PMT_DISC_DWORDS];
 	struct bin_attribute	pmt_bin_attr;
 	const struct attribute_group *attr_grp;
 	struct kobject		*kobj;

index 07ea563f524e..843cda8f8644 100644
@@ -28,6 +28,7 @@
 #define INTEL_DVSEC_TABLE_BAR(x)	((x) & GENMASK(2, 0))
 #define INTEL_DVSEC_TABLE_OFFSET(x)	((x) & GENMASK(31, 3))
 #define TABLE_OFFSET_SHIFT		3
+#define PMT_DISC_DWORDS		4
 
 struct device;
 struct pci_dev;

@@ -122,7 +123,7 @@ struct intel_vsec_platform_info {
 	struct device *parent;
 	struct intel_vsec_header **headers;
 	const struct vsec_feature_dependency *deps;
-	u32 (*acpi_disc)[4];
+	u32 (*acpi_disc)[PMT_DISC_DWORDS];
 	enum intel_vsec_disc_source src;
 	void *priv_data;
 	unsigned long caps;

@@ -153,7 +154,7 @@ struct intel_vsec_platform_info {
 struct intel_vsec_device {
 	struct auxiliary_device auxdev;
 	struct device *dev;
-	u32 (*acpi_disc)[4];
+	u32 (*acpi_disc)[PMT_DISC_DWORDS];
 	enum intel_vsec_disc_source src;
 	struct ida *ida;
 	int num_resources;

index 55cf567febe4..b4c7399f8369 100644
@@ -14,10 +14,15 @@
 
 #include <linux/acpi.h>
 #include <linux/bits.h>
+#include <linux/cleanup.h>
+#include <linux/intel_vsec.h>
 #include <linux/platform_device.h>
+#include <linux/uuid.h>
 
 struct telem_endpoint;
 
+DEFINE_FREE(pmc_acpi_free, void *, if (_T) ACPI_FREE(_T))
+
 #define SLP_S0_RES_COUNTER_MASK			GENMASK(31, 0)
 
 #define PMC_BASE_ADDR_DEFAULT			0xFE000000

@@ -622,6 +627,8 @@ int pmc_core_pmt_get_blk_sub_req(struct pmc_dev *pmcdev, struct pmc *pmc,
 extern const struct file_operations pmc_core_substate_req_regs_fops;
 extern const struct file_operations pmc_core_substate_blk_req_fops;
 
+extern const guid_t intel_vsec_guid;
+
 #define pmc_for_each_mode(mode, pmc)						\
 	for (unsigned int __i = 0, __cond;					\
 	     __cond = __i < (pmc)->num_lpm_modes,				\

@@ -643,4 +650,13 @@ static const struct file_operations __name ## _fops = {			\
 	.release	= single_release,				\
 }
 
+struct intel_vsec_header;
+union acpi_object;
+
+/* Avoid checkpatch warning */
+typedef u32 (*acpi_disc_t)[PMT_DISC_DWORDS];
+
+acpi_disc_t pmc_parse_telem_dsd(union acpi_object *obj,
+				struct intel_vsec_header *header);
+union acpi_object *pmc_find_telem_guid(union acpi_object *dsd);
 #endif /* PMC_CORE_H */

216 lines not on this page · raw message

index 6f6e83e70fc5..1deb4d71da3f 100644
@@ -149,7 +149,7 @@ int pmc_ssram_telemetry_get_pmc_info(unsigned int pmc_idx,
 }
 EXPORT_SYMBOL_GPL(pmc_ssram_telemetry_get_pmc_info);
 
-static int intel_pmc_ssram_telemetry_probe(struct pci_dev *pcidev, const struct pci_device_id *id)
+static int pmc_ssram_telemetry_probe(struct pci_dev *pcidev, const struct pci_device_id *id)
 {
 	int ret;
 

@@ -183,7 +183,7 @@ static int intel_pmc_ssram_telemetry_probe(struct pci_dev *pcidev, const struct
 	return ret;
 }
 
-static const struct pci_device_id intel_pmc_ssram_telemetry_pci_ids[] = {
+static const struct pci_device_id pmc_ssram_telemetry_pci_ids[] = {
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_MTL_SOCM) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_ARL_SOCS) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_ARL_SOCM) },

@@ -193,14 +193,14 @@ static const struct pci_device_id intel_pmc_ssram_telemetry_pci_ids[] = {
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_WCL_PCDN) },
 	{ }
 };
-MODULE_DEVICE_TABLE(pci, intel_pmc_ssram_telemetry_pci_ids);
+MODULE_DEVICE_TABLE(pci, pmc_ssram_telemetry_pci_ids);
 
-static struct pci_driver intel_pmc_ssram_telemetry_driver = {
+static struct pci_driver pmc_ssram_telemetry_driver = {
 	.name = "intel_pmc_ssram_telemetry",
-	.id_table = intel_pmc_ssram_telemetry_pci_ids,
-	.probe = intel_pmc_ssram_telemetry_probe,
+	.id_table = pmc_ssram_telemetry_pci_ids,
+	.probe = pmc_ssram_telemetry_probe,
 };
-module_pci_driver(intel_pmc_ssram_telemetry_driver);
+module_pci_driver(pmc_ssram_telemetry_driver);
 
 MODULE_IMPORT_NS("INTEL_VSEC");
 MODULE_AUTHOR("Xi Pardee <[email protected]>");

index 1deb4d71da3f..05f213aa108f 100644
@@ -6,6 +6,7 @@
  */
 
 #include <linux/cleanup.h>
+#include <linux/device.h>
 #include <linux/intel_vsec.h>
 #include <linux/pci.h>
 #include <linux/types.h>

@@ -24,6 +25,18 @@
 
 DEFINE_FREE(pmc_ssram_telemetry_iounmap, void __iomem *, if (_T) iounmap(_T))
 
+enum resource_method {
+	RES_METHOD_PCI,
+};
+
+struct ssram_type {
+	enum resource_method method;
+};
+
+static const struct ssram_type pci_main = {
+	.method = RES_METHOD_PCI,
+};
+
 static struct pmc_ssram_telemetry *pmc_ssram_telems;
 static bool device_probed;
 

@@ -69,7 +82,7 @@ static inline u64 get_base(void __iomem *addr, u32 offset)
 }
 
 static int
-pmc_ssram_telemetry_get_pmc(struct pci_dev *pcidev, unsigned int pmc_idx, u32 offset)
+pmc_ssram_telemetry_get_pmc_pci(struct pci_dev *pcidev, unsigned int pmc_idx, u32 offset)
 {
 	void __iomem __free(pmc_ssram_telemetry_iounmap) *tmp_ssram = NULL;
 	void __iomem __free(pmc_ssram_telemetry_iounmap) *ssram = NULL;

@@ -109,6 +122,20 @@ pmc_ssram_telemetry_get_pmc(struct pci_dev *pcidev, unsigned int pmc_idx, u32 of
 	return pmc_ssram_telemetry_add_pmt(pcidev, ssram_base, ssram);
 }
 
+static int pmc_ssram_telemetry_pci_init(struct pci_dev *pcidev)
+{
+	int ret;
+
+	ret = pmc_ssram_telemetry_get_pmc_pci(pcidev, PMC_IDX_MAIN, 0);
+	if (ret)
+		return ret;
+
+	pmc_ssram_telemetry_get_pmc_pci(pcidev, PMC_IDX_IOE, SSRAM_IOE_OFFSET);
+	pmc_ssram_telemetry_get_pmc_pci(pcidev, PMC_IDX_PCH, SSRAM_PCH_OFFSET);
+
+	return 0;
+}
+
 /**
  * pmc_ssram_telemetry_get_pmc_info() - Get a PMC devid and base_addr information
  * @pmc_idx:               Index of the PMC

@@ -151,6 +178,8 @@ EXPORT_SYMBOL_GPL(pmc_ssram_telemetry_get_pmc_info);
 
 static int pmc_ssram_telemetry_probe(struct pci_dev *pcidev, const struct pci_device_id *id)
 {
+	const struct ssram_type *ssram_type;
+	enum resource_method method;
 	int ret;
 
 	pmc_ssram_telems = devm_kzalloc(&pcidev->dev, sizeof(*pmc_ssram_telems) * MAX_NUM_PMC,

@@ -160,18 +189,25 @@ static int pmc_ssram_telemetry_probe(struct pci_dev *pcidev, const struct pci_de
 		goto probe_finish;
 	}
 
+	ssram_type = (const struct ssram_type *)id->driver_data;
+	if (!ssram_type) {
+		dev_dbg(&pcidev->dev, "missing driver data\n");
+		ret = -EINVAL;
+		goto probe_finish;
+	}
+
+	method = ssram_type->method;
+
 	ret = pcim_enable_device(pcidev);
 	if (ret) {
 		dev_dbg(&pcidev->dev, "failed to enable PMC SSRAM device\n");
 		goto probe_finish;
 	}
 
-	ret = pmc_ssram_telemetry_get_pmc(pcidev, PMC_IDX_MAIN, 0);
-	if (ret)
-		goto probe_finish;
-
-	pmc_ssram_telemetry_get_pmc(pcidev, PMC_IDX_IOE, SSRAM_IOE_OFFSET);
-	pmc_ssram_telemetry_get_pmc(pcidev, PMC_IDX_PCH, SSRAM_PCH_OFFSET);
+	if (method == RES_METHOD_PCI)
+		ret = pmc_ssram_telemetry_pci_init(pcidev);
+	else
+		ret = -EINVAL;
 
 probe_finish:
 	/*

@@ -184,13 +220,20 @@ static int pmc_ssram_telemetry_probe(struct pci_dev *pcidev, const struct pci_de
 }
 
 static const struct pci_device_id pmc_ssram_telemetry_pci_ids[] = {
-	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_MTL_SOCM) },
-	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_ARL_SOCS) },
-	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_ARL_SOCM) },
-	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_LNL_SOCM) },
-	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_PTL_PCDH) },
-	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_PTL_PCDP) },
-	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_WCL_PCDN) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_MTL_SOCM),
+		.driver_data = (kernel_ulong_t)&pci_main },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_ARL_SOCS),
+		.driver_data = (kernel_ulong_t)&pci_main },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_ARL_SOCM),
+		.driver_data = (kernel_ulong_t)&pci_main },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_LNL_SOCM),
+		.driver_data = (kernel_ulong_t)&pci_main },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_PTL_PCDH),
+		.driver_data = (kernel_ulong_t)&pci_main },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_PTL_PCDP),
+		.driver_data = (kernel_ulong_t)&pci_main },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_WCL_PCDN),
+		.driver_data = (kernel_ulong_t)&pci_main },
 	{ }
 };
 MODULE_DEVICE_TABLE(pci, pmc_ssram_telemetry_pci_ids);

index 05f213aa108f..211d842df449 100644
@@ -5,6 +5,7 @@
  * Copyright (c) 2023, Intel Corporation.
  */
 
+#include <linux/bits.h>
 #include <linux/cleanup.h>
 #include <linux/device.h>
 #include <linux/intel_vsec.h>

@@ -22,6 +23,7 @@
 #define SSRAM_PCH_OFFSET	0x60
 #define SSRAM_IOE_OFFSET	0x68
 #define SSRAM_DEVID_OFFSET	0x70
+#define SSRAM_BASE_ADDR_MASK	GENMASK_ULL(63, 3)
 
 DEFINE_FREE(pmc_ssram_telemetry_iounmap, void __iomem *, if (_T) iounmap(_T))
 

@@ -40,6 +42,23 @@ static const struct ssram_type pci_main = {
 static struct pmc_ssram_telemetry *pmc_ssram_telems;
 static bool device_probed;
 
+static inline u64 get_base(void __iomem *addr, u32 offset)
+{
+	return lo_hi_readq(addr + offset) & SSRAM_BASE_ADDR_MASK;
+}
+
+static void pmc_ssram_get_devid_pwrmbase(void __iomem *ssram, unsigned int pmc_idx)
+{
+	u64 pwrm_base;
+	u16 devid;
+
+	pwrm_base = get_base(ssram, SSRAM_PWRM_OFFSET);
+	devid = readw(ssram + SSRAM_DEVID_OFFSET);
+
+	pmc_ssram_telems[pmc_idx].devid = devid;
+	pmc_ssram_telems[pmc_idx].base_addr = pwrm_base;
+}
+
 static int
 pmc_ssram_telemetry_add_pmt(struct pci_dev *pcidev, u64 ssram_base, void __iomem *ssram)
 {

@@ -76,18 +95,12 @@ pmc_ssram_telemetry_add_pmt(struct pci_dev *pcidev, u64 ssram_base, void __iomem
 	return intel_vsec_register(&pcidev->dev, &info);
 }
 
-static inline u64 get_base(void __iomem *addr, u32 offset)
-{
-	return lo_hi_readq(addr + offset) & GENMASK_ULL(63, 3);
-}
-
 static int
 pmc_ssram_telemetry_get_pmc_pci(struct pci_dev *pcidev, unsigned int pmc_idx, u32 offset)
 {
 	void __iomem __free(pmc_ssram_telemetry_iounmap) *tmp_ssram = NULL;
 	void __iomem __free(pmc_ssram_telemetry_iounmap) *ssram = NULL;
-	u64 ssram_base, pwrm_base;
-	u16 devid;
+	u64 ssram_base;
 
 	ssram_base = pci_resource_start(pcidev, 0);
 	tmp_ssram = ioremap(ssram_base, SSRAM_HDR_SIZE);

@@ -112,11 +125,7 @@ pmc_ssram_telemetry_get_pmc_pci(struct pci_dev *pcidev, unsigned int pmc_idx, u3
 		ssram = no_free_ptr(tmp_ssram);
 	}
 
-	pwrm_base = get_base(ssram, SSRAM_PWRM_OFFSET);
-	devid = readw(ssram + SSRAM_DEVID_OFFSET);
-
-	pmc_ssram_telems[pmc_idx].devid = devid;
-	pmc_ssram_telems[pmc_idx].base_addr = pwrm_base;
+	pmc_ssram_get_devid_pwrmbase(ssram, pmc_idx);
 
 	/* Find and register and PMC telemetry entries */
 	return pmc_ssram_telemetry_add_pmt(pcidev, ssram_base, ssram);

index 211d842df449..3349f65ae7bd 100644
@@ -5,6 +5,7 @@
  * Copyright (c) 2023, Intel Corporation.
  */
 
+#include <linux/bitmap.h>
 #include <linux/bits.h>
 #include <linux/cleanup.h>
 #include <linux/device.h>

@@ -24,6 +25,7 @@
 #define SSRAM_IOE_OFFSET	0x68
 #define SSRAM_DEVID_OFFSET	0x70
 #define SSRAM_BASE_ADDR_MASK	GENMASK_ULL(63, 3)
+#define SSRAM_PCI_PMC_MASK	(BIT(PMC_IDX_MAIN) | BIT(PMC_IDX_IOE) | BIT(PMC_IDX_PCH))
 
 DEFINE_FREE(pmc_ssram_telemetry_iounmap, void __iomem *, if (_T) iounmap(_T))
 

@@ -39,15 +41,37 @@ static const struct ssram_type pci_main = {
 	.method = RES_METHOD_PCI,
 };
 
-static struct pmc_ssram_telemetry *pmc_ssram_telems;
-static bool device_probed;
+enum pmc_ssram_state {
+	PMC_SSRAM_UNPROBED = 0,
+	PMC_SSRAM_PROBING,
+	PMC_SSRAM_PRESENT,
+	PMC_SSRAM_ABSENT,
+};
+
+static enum pmc_ssram_state pmc_ssram_state[MAX_NUM_PMC];
+static struct pmc_ssram_telemetry pmc_ssram_telems[MAX_NUM_PMC];
+
+struct pmc_ssram_probe_cache {
+	/* Per-index values staged by probe before publishing globally. */
+	struct pmc_ssram_telemetry telems[MAX_NUM_PMC];
+	/* PMCs this probe instance is responsible for publishing. */
+	unsigned long owned_mask;
+	/* Subset of owned_mask that was discovered successfully. */
+	unsigned long valid_mask;
+};
+
+struct pmc_ssram_drvdata {
+	/* PMCs published by this bound device; used to unpublish on remove. */
+	unsigned long owned_mask;
+};
 
 static inline u64 get_base(void __iomem *addr, u32 offset)
 {
 	return lo_hi_readq(addr + offset) & SSRAM_BASE_ADDR_MASK;
 }
 
-static void pmc_ssram_get_devid_pwrmbase(void __iomem *ssram, unsigned int pmc_idx)
+static void pmc_ssram_get_devid_pwrmbase(struct pmc_ssram_probe_cache *probe_cache,
+					 void __iomem *ssram, unsigned int pmc_idx)
 {
 	u64 pwrm_base;
 	u16 devid;

@@ -55,8 +79,45 @@ static void pmc_ssram_get_devid_pwrmbase(void __iomem *ssram, unsigned int pmc_i
 	pwrm_base = get_base(ssram, SSRAM_PWRM_OFFSET);
 	devid = readw(ssram + SSRAM_DEVID_OFFSET);
 
-	pmc_ssram_telems[pmc_idx].devid = devid;
-	pmc_ssram_telems[pmc_idx].base_addr = pwrm_base;
+	probe_cache->telems[pmc_idx].base_addr = pwrm_base;
+	probe_cache->telems[pmc_idx].devid = devid;
+}
+
+static void pmc_ssram_publish_absent(unsigned int pmc_idx)
+{
+	/*
+	 * Publish only the state without modifying base_addr and devid. This
+	 * lets a reader that already observed PRESENT finish copying the
+	 * previous values even if unbind concurrently publishes ABSENT. Readers
+	 * that observe ABSENT return -ENODEV without accessing data.
+	 */
+	smp_store_release(&pmc_ssram_state[pmc_idx], PMC_SSRAM_ABSENT);
+}
+
+static void pmc_ssram_publish_present(struct pmc_ssram_probe_cache *probe_cache,
+				      unsigned int pmc_idx)
+{
+	/*
+	 * The devid and base_addr fields are read from hardware MMIO registers
+	 * whose values are stable for a given PMC index. A reader that observed
+	 * PRESENT from an earlier probe can safely copy them while a concurrent
+	 * rebind republishes those fields because both probes read the same
+	 * hardware values.
+	 */
+	pmc_ssram_telems[pmc_idx] = probe_cache->telems[pmc_idx];
+	/*
+	 * Publish base_addr and devid before publishing PRESENT. Pairs with the
+	 * acquire load in the reader that consumes them after observing PRESENT.
+	 */
+	smp_store_release(&pmc_ssram_state[pmc_idx], PMC_SSRAM_PRESENT);
+}
+
+static void pmc_ssram_mark_probing(unsigned long mask)
+{
+	unsigned long bit;
+
+	for_each_set_bit(bit, &mask, MAX_NUM_PMC)
+		WRITE_ONCE(pmc_ssram_state[bit], PMC_SSRAM_PROBING);
 }
 
 static int

@@ -96,11 +157,14 @@ pmc_ssram_telemetry_add_pmt(struct pci_dev *pcidev, u64 ssram_base, void __iomem
 }
 
 static int
-pmc_ssram_telemetry_get_pmc_pci(struct pci_dev *pcidev, unsigned int pmc_idx, u32 offset)
+pmc_ssram_telemetry_get_pmc_pci(struct pci_dev *pcidev,
+				struct pmc_ssram_probe_cache *probe_cache,
+				unsigned int pmc_idx, u32 offset)
 {
 	void __iomem __free(pmc_ssram_telemetry_iounmap) *tmp_ssram = NULL;
 	void __iomem __free(pmc_ssram_telemetry_iounmap) *ssram = NULL;
 	u64 ssram_base;
+	int ret;
 
 	ssram_base = pci_resource_start(pcidev, 0);
 	tmp_ssram = ioremap(ssram_base, SSRAM_HDR_SIZE);

@@ -125,22 +189,38 @@ pmc_ssram_telemetry_get_pmc_pci(struct pci_dev *pcidev, unsigned int pmc_idx, u3
 		ssram = no_free_ptr(tmp_ssram);
 	}
 
-	pmc_ssram_get_devid_pwrmbase(ssram, pmc_idx);
+	pmc_ssram_get_devid_pwrmbase(probe_cache, ssram, pmc_idx);
 
 	/* Find and register and PMC telemetry entries */
-	return pmc_ssram_telemetry_add_pmt(pcidev, ssram_base, ssram);
+	ret = pmc_ssram_telemetry_add_pmt(pcidev, ssram_base, ssram);
+	if (ret)
+		return ret;
+
+	probe_cache->valid_mask |= BIT(pmc_idx);
+
+	return 0;
 }
 
-static int pmc_ssram_telemetry_pci_init(struct pci_dev *pcidev)
+static int pmc_ssram_telemetry_pci_init(struct pci_dev *pcidev,
+					struct pmc_ssram_probe_cache *probe_cache)
 {
 	int ret;
 
-	ret = pmc_ssram_telemetry_get_pmc_pci(pcidev, PMC_IDX_MAIN, 0);
+	ret = pmc_ssram_telemetry_get_pmc_pci(pcidev, probe_cache, PMC_IDX_MAIN, 0);
 	if (ret)
 		return ret;
 
-	pmc_ssram_telemetry_get_pmc_pci(pcidev, PMC_IDX_IOE, SSRAM_IOE_OFFSET);
-	pmc_ssram_telemetry_get_pmc_pci(pcidev, PMC_IDX_PCH, SSRAM_PCH_OFFSET);
+	/*
+	 * If MAIN PMC enumeration is successful but either IOE or PCH fail,
+	 * don't fail probe as the MAIN PMC is still useful as it provides the
+	 * global reset and slp_s0 counter access. Failed or missing secondary
+	 * PMCs are left out of valid_mask and published as absent.
+	 */
+	pmc_ssram_telemetry_get_pmc_pci(pcidev, probe_cache, PMC_IDX_IOE,
+					SSRAM_IOE_OFFSET);
+
+	pmc_ssram_telemetry_get_pmc_pci(pcidev, probe_cache, PMC_IDX_PCH,
+					SSRAM_PCH_OFFSET);
 
 	return 0;
 }

@@ -150,62 +230,106 @@ static int pmc_ssram_telemetry_pci_init(struct pci_dev *pcidev)
  * @pmc_idx:               Index of the PMC
  * @pmc_ssram_telemetry:   pmc_ssram_telemetry structure to store the PMC information
  *
+ * State flow per PMC index:
+ * - PMC_SSRAM_UNPROBED: Probe has not started for this index.
+ * - PMC_SSRAM_PROBING:  Probe is currently discovering data for this index.
+ * - PMC_SSRAM_PRESENT:  base_addr/devid were published and can be read.
+ * - PMC_SSRAM_ABSENT:   No data is available for this index.
+ *
+ * Readers use an acquire load of the state. If state is PRESENT, reads of
+ * base_addr/devid are ordered after the state observation and pair with the
+ * writer's release-store when publishing PRESENT.
+ *
  * Return:
  * * 0           - Success
  * * -EAGAIN     - Probe function has not finished yet. Try again.
  * * -EINVAL     - Invalid pmc_idx
- * * -ENODEV     - PMC device is not available
+ * * -ENODEV     - PMC device is not available (hardware absent or driver failed to initialize)
  */
 int pmc_ssram_telemetry_get_pmc_info(unsigned int pmc_idx,
 				     struct pmc_ssram_telemetry *pmc_ssram_telemetry)
 {
+	enum pmc_ssram_state state;
+
+	if (pmc_idx >= MAX_NUM_PMC)
+		return -EINVAL;
+
 	/*
 	 * PMCs are discovered in probe function. If this function is called before
-	 * probe function complete, the result would be invalid. Use device_probed
-	 * variable to avoid this case. Return -EAGAIN to inform the consumer to call
-	 * again later.
+	 * probe function complete, the result would be invalid. Use per-PMC state
+	 * to inform the consumer to call again later.
 	 */
-	if (!device_probed)
+	state = smp_load_acquire(&pmc_ssram_state[pmc_idx]);
+	if (state == PMC_SSRAM_UNPROBED || state == PMC_SSRAM_PROBING)
 		return -EAGAIN;
 
-	/*
-	 * Memory barrier is used to ensure the correct read order between
-	 * device_probed variable and PMC info.
-	 */
-	smp_rmb();
-	if (pmc_idx >= MAX_NUM_PMC)
-		return -EINVAL;
-
-	if (!pmc_ssram_telems || !pmc_ssram_telems[pmc_idx].devid)
+	if (state == PMC_SSRAM_ABSENT)
 		return -ENODEV;
 
+	/*
+	 * Acquire semantics order reads of devid and base_addr after observing
+	 * PRESENT and pair with the writer's release-store.
+	 */
 	pmc_ssram_telemetry->devid = pmc_ssram_telems[pmc_idx].devid;
 	pmc_ssram_telemetry->base_addr = pmc_ssram_telems[pmc_idx].base_addr;
 	return 0;
 }
 EXPORT_SYMBOL_GPL(pmc_ssram_telemetry_get_pmc_info);
 
+static void pmc_ssram_publish_absent_mask(unsigned long mask)
+{
+	unsigned long bit;
+
+	for_each_set_bit(bit, &mask, MAX_NUM_PMC)
+		pmc_ssram_publish_absent(bit);
+}
+
+static void pmc_ssram_publish_telems(struct pmc_ssram_probe_cache *probe_cache, int ret)
+{
+	unsigned long bit;
+
+	/* If probe failed, all owned indexes become absent for readers. */
+	if (ret) {
+		pmc_ssram_publish_absent_mask(probe_cache->owned_mask);
+		return;
+	}
+
+	/* Publish each owned index independently based on discovery result. */
+	for_each_set_bit(bit, &probe_cache->owned_mask, MAX_NUM_PMC) {
+		if (probe_cache->valid_mask & BIT(bit))
+			pmc_ssram_publish_present(probe_cache, bit);
+		else
+			pmc_ssram_publish_absent(bit);
+	}
+}
+
 static int pmc_ssram_telemetry_probe(struct pci_dev *pcidev, const struct pci_device_id *id)
 {
+	struct pmc_ssram_probe_cache probe_cache = {};
+	struct pmc_ssram_drvdata *drvdata;
 	const struct ssram_type *ssram_type;
 	enum resource_method method;
 	int ret;
 
-	pmc_ssram_telems = devm_kzalloc(&pcidev->dev, sizeof(*pmc_ssram_telems) * MAX_NUM_PMC,
-					GFP_KERNEL);
-	if (!pmc_ssram_telems) {
-		ret = -ENOMEM;
-		goto probe_finish;
-	}
-
 	ssram_type = (const struct ssram_type *)id->driver_data;
 	if (!ssram_type) {
 		dev_dbg(&pcidev->dev, "missing driver data\n");
-		ret = -EINVAL;
-		goto probe_finish;
+		return -EINVAL;
 	}
 
 	method = ssram_type->method;
+	if (method == RES_METHOD_PCI)
+		probe_cache.owned_mask = SSRAM_PCI_PMC_MASK;
+	else
+		return -EINVAL;
+
+	pmc_ssram_mark_probing(probe_cache.owned_mask);
+
+	drvdata = devm_kzalloc(&pcidev->dev, sizeof(*drvdata), GFP_KERNEL);
+	if (!drvdata) {
+		ret = -ENOMEM;
+		goto probe_finish;
+	}
 
 	ret = pcim_enable_device(pcidev);
 	if (ret) {

@@ -214,20 +338,29 @@ static int pmc_ssram_telemetry_probe(struct pci_dev *pcidev, const struct pci_de
 	}
 
 	if (method == RES_METHOD_PCI)
-		ret = pmc_ssram_telemetry_pci_init(pcidev);
+		ret = pmc_ssram_telemetry_pci_init(pcidev, &probe_cache);
 	else
 		ret = -EINVAL;
 
+	if (!ret) {
+		drvdata->owned_mask = probe_cache.owned_mask;
+		pci_set_drvdata(pcidev, drvdata);
+	}
+
 probe_finish:
-	/*
-	 * Memory barrier is used to ensure the correct write order between PMC info
-	 * and device_probed variable.
-	 */
-	smp_wmb();
-	device_probed = true;
+	pmc_ssram_publish_telems(&probe_cache, ret);
+
 	return ret;
 }
 
+static void pmc_ssram_telemetry_remove(struct pci_dev *pcidev)
+{
+	struct pmc_ssram_drvdata *drvdata = pci_get_drvdata(pcidev);
+
+	if (drvdata)
+		pmc_ssram_publish_absent_mask(drvdata->owned_mask);
+}
+
 static const struct pci_device_id pmc_ssram_telemetry_pci_ids[] = {
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_MTL_SOCM),
 		.driver_data = (kernel_ulong_t)&pci_main },

@@ -251,6 +384,7 @@ static struct pci_driver pmc_ssram_telemetry_driver = {
 	.name = "intel_pmc_ssram_telemetry",
 	.id_table = pmc_ssram_telemetry_pci_ids,
 	.probe = pmc_ssram_telemetry_probe,
+	.remove = pmc_ssram_telemetry_remove,
 };
 module_pci_driver(pmc_ssram_telemetry_driver);
 

index 3349f65ae7bd..10462fa7ebbf 100644
@@ -5,6 +5,7 @@
  * Copyright (c) 2023, Intel Corporation.
  */
 
+#include <linux/acpi.h>
 #include <linux/bitmap.h>
 #include <linux/bits.h>
 #include <linux/cleanup.h>

@@ -31,14 +32,17 @@ DEFINE_FREE(pmc_ssram_telemetry_iounmap, void __iomem *, if (_T) iounmap(_T))
 
 enum resource_method {
 	RES_METHOD_PCI,
+	RES_METHOD_ACPI,
 };
 
 struct ssram_type {
 	enum resource_method method;
+	enum pmc_index p_index;
 };
 
 static const struct ssram_type pci_main = {
 	.method = RES_METHOD_PCI,
+	.p_index = PMC_IDX_MAIN,
 };
 
 enum pmc_ssram_state {

@@ -225,6 +229,73 @@ static int pmc_ssram_telemetry_pci_init(struct pci_dev *pcidev,
 	return 0;
 }
 
+static int pmc_ssram_telemetry_get_pmc_acpi(struct pci_dev *pcidev,
+					    struct pmc_ssram_probe_cache *probe_cache,
+					    unsigned int pmc_idx)
+{
+	u64 ssram_base;
+
+	ssram_base = pci_resource_start(pcidev, 0);
+	if (!ssram_base)
+		return -ENODEV;
+
+	void __iomem __free(pmc_ssram_telemetry_iounmap) *ssram =
+		ioremap(ssram_base, SSRAM_HDR_SIZE);
+	if (!ssram)
+		return -ENOMEM;
+
+	pmc_ssram_get_devid_pwrmbase(probe_cache, ssram, pmc_idx);
+	probe_cache->valid_mask |= BIT(pmc_idx);
+
+	return 0;
+}
+
+static int pmc_ssram_telemetry_acpi_init(struct pci_dev *pcidev,
+					 struct pmc_ssram_probe_cache *probe_cache,
+					 enum pmc_index index)
+{
+	struct intel_vsec_header header;
+	struct intel_vsec_header *headers[2] = { &header, NULL };
+	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER, NULL };
+	struct intel_vsec_platform_info info = { };
+	union acpi_object *dsd;
+	acpi_handle handle;
+	acpi_status status;
+	int ret;
+
+	handle = ACPI_HANDLE(&pcidev->dev);
+	if (!handle)
+		return -ENODEV;
+
+	status = acpi_evaluate_object(handle, "_DSD", NULL, &buf);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	void *dsd_buf __free(pmc_acpi_free) = buf.pointer;
+
+	dsd = pmc_find_telem_guid(dsd_buf);
+	if (!dsd)
+		return -ENODEV;
+
+	acpi_disc_t disc __free(kfree) = pmc_parse_telem_dsd(dsd, &header);
+	if (IS_ERR(disc))
+		return PTR_ERR(disc);
+
+	info.headers = headers;
+	info.caps = VSEC_CAP_TELEMETRY;
+	info.acpi_disc = disc;
+	info.src = INTEL_VSEC_DISC_ACPI;
+
+	/* This is an ACPI companion device. PCI BAR will be used for base addr. */
+	info.base_addr = 0;
+
+	ret = intel_vsec_register(&pcidev->dev, &info);
+	if (ret)
+		return ret;
+
+	return pmc_ssram_telemetry_get_pmc_acpi(pcidev, probe_cache, index);
+}
+
 /**
  * pmc_ssram_telemetry_get_pmc_info() - Get a PMC devid and base_addr information
  * @pmc_idx:               Index of the PMC

@@ -309,6 +380,7 @@ static int pmc_ssram_telemetry_probe(struct pci_dev *pcidev, const struct pci_de
 	struct pmc_ssram_drvdata *drvdata;
 	const struct ssram_type *ssram_type;
 	enum resource_method method;
+	enum pmc_index index;
 	int ret;
 
 	ssram_type = (const struct ssram_type *)id->driver_data;

@@ -317,9 +389,12 @@ static int pmc_ssram_telemetry_probe(struct pci_dev *pcidev, const struct pci_de
 		return -EINVAL;
 	}
 
+	index = ssram_type->p_index;
 	method = ssram_type->method;
 	if (method == RES_METHOD_PCI)
 		probe_cache.owned_mask = SSRAM_PCI_PMC_MASK;
+	else if (method == RES_METHOD_ACPI)
+		probe_cache.owned_mask = BIT(index);
 	else
 		return -EINVAL;
 

@@ -339,6 +414,8 @@ static int pmc_ssram_telemetry_probe(struct pci_dev *pcidev, const struct pci_de
 
 	if (method == RES_METHOD_PCI)
 		ret = pmc_ssram_telemetry_pci_init(pcidev, &probe_cache);
+	else if (method == RES_METHOD_ACPI)
+		ret = pmc_ssram_telemetry_acpi_init(pcidev, &probe_cache, index);
 	else
 		ret = -EINVAL;
 

@@ -389,6 +466,7 @@ static struct pci_driver pmc_ssram_telemetry_driver = {
 module_pci_driver(pmc_ssram_telemetry_driver);
 
 MODULE_IMPORT_NS("INTEL_VSEC");
+MODULE_IMPORT_NS("INTEL_PMC_CORE");
 MODULE_AUTHOR("Xi Pardee <[email protected]>");
 MODULE_DESCRIPTION("Intel PMC SSRAM Telemetry driver");
 MODULE_LICENSE("GPL");

index 10462fa7ebbf..9a8922045ab7 100644
@@ -198,7 +198,7 @@ pmc_ssram_telemetry_get_pmc_pci(struct pci_dev *pcidev,
 	/* Find and register and PMC telemetry entries */
 	ret = pmc_ssram_telemetry_add_pmt(pcidev, ssram_base, ssram);
 	if (ret)
-		return ret;
+		dev_warn(&pcidev->dev, "could not register PMT\n");
 
 	probe_cache->valid_mask |= BIT(pmc_idx);
 

@@ -291,7 +291,7 @@ static int pmc_ssram_telemetry_acpi_init(struct pci_dev *pcidev,
 
 	ret = intel_vsec_register(&pcidev->dev, &info);
 	if (ret)
-		return ret;
+		dev_warn(&pcidev->dev, "could not register PMT\n");
 
 	return pmc_ssram_telemetry_get_pmc_acpi(pcidev, probe_cache, index);
 }

index 9a8922045ab7..8e280ec525a6 100644
@@ -45,6 +45,16 @@ static const struct ssram_type pci_main = {
 	.p_index = PMC_IDX_MAIN,
 };
 
+static const struct ssram_type acpi_main = {
+	.method = RES_METHOD_ACPI,
+	.p_index = PMC_IDX_MAIN,
+};
+
+static const struct ssram_type acpi_pch = {
+	.method = RES_METHOD_ACPI,
+	.p_index = PMC_IDX_PCH,
+};
+
 enum pmc_ssram_state {
 	PMC_SSRAM_UNPROBED = 0,
 	PMC_SSRAM_PROBING,

@@ -453,6 +463,12 @@ static const struct pci_device_id pmc_ssram_telemetry_pci_ids[] = {
 		.driver_data = (kernel_ulong_t)&pci_main },
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_WCL_PCDN),
 		.driver_data = (kernel_ulong_t)&pci_main },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_NVL_PCDH),
+		.driver_data = (kernel_ulong_t)&acpi_main },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_NVL_PCDS),
+		.driver_data = (kernel_ulong_t)&acpi_main },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PMC_DEVID_NVL_PCHS),
+		.driver_data = (kernel_ulong_t)&acpi_pch },
 	{ }
 };
 MODULE_DEVICE_TABLE(pci, pmc_ssram_telemetry_pci_ids);