diff --git a/drivers/cxl/core/hdm.c b/drivers/cxl/core/hdm.c
index 80eccae6ba9e..45deda18ed32 100644
--- a/drivers/cxl/core/hdm.c
+++ b/drivers/cxl/core/hdm.c
@@ -101,11 +101,34 @@ static int map_hdm_decoder_regs(struct cxl_port *port, void __iomem *crb,
 				      BIT(CXL_CM_CAP_CAP_ID_HDM));
 }
 
+static struct cxl_hdm *devm_cxl_setup_emulated_hdm(struct cxl_port *port,
+						   struct cxl_endpoint_dvsec_info *info)
+{
+	struct device *dev = &port->dev;
+	struct cxl_hdm *cxlhdm;
+
+	if (!info->mem_enabled)
+		return ERR_PTR(-ENODEV);
+
+	cxlhdm = devm_kzalloc(dev, sizeof(*cxlhdm), GFP_KERNEL);
+	if (!cxlhdm)
+		return ERR_PTR(-ENOMEM);
+
+	cxlhdm->port = port;
+	cxlhdm->decoder_count = info->ranges;
+	cxlhdm->target_count = info->ranges;
+	dev_set_drvdata(&port->dev, cxlhdm);
+
+	return cxlhdm;
+}
+
 /**
  * devm_cxl_setup_hdm - map HDM decoder component registers
  * @port: cxl_port to map
+ * @info: cached DVSEC range register info
  */
-struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port)
+struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port,
+				   struct cxl_endpoint_dvsec_info *info)
 {
 	struct device *dev = &port->dev;
 	struct cxl_hdm *cxlhdm;
@@ -119,6 +142,9 @@ struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port)
 	cxlhdm->port = port;
 	crb = ioremap(port->component_reg_phys, CXL_COMPONENT_REG_BLOCK_SIZE);
 	if (!crb) {
+		if (info && info->mem_enabled)
+			return devm_cxl_setup_emulated_hdm(port, info);
+
 		dev_err(dev, "No component registers mapped\n");
 		return ERR_PTR(-ENXIO);
 	}
@@ -688,9 +714,60 @@ static int cxl_decoder_reset(struct cxl_decoder *cxld)
 	return 0;
 }
 
+static int cxl_setup_hdm_decoder_from_dvsec(struct cxl_port *port,
+					    struct cxl_decoder *cxld, int which,
+					    struct cxl_endpoint_dvsec_info *info)
+{
+	if (!is_cxl_endpoint(port))
+		return -EOPNOTSUPP;
+
+	if (!range_len(&info->dvsec_range[which]))
+		return -ENOENT;
+
+	cxld->target_type = CXL_DECODER_EXPANDER;
+	cxld->commit = NULL;
+	cxld->reset = NULL;
+	cxld->hpa_range = info->dvsec_range[which];
+
+	/*
+	 * Set the emulated decoder as locked pending additional support to
+	 * change the range registers at run time.
+	 */
+	cxld->flags |= CXL_DECODER_F_ENABLE | CXL_DECODER_F_LOCK;
+	port->commit_end = cxld->id;
+
+	return 0;
+}
+
+static bool should_emulate_decoders(struct cxl_port *port)
+{
+	struct cxl_hdm *cxlhdm = dev_get_drvdata(&port->dev);
+	void __iomem *hdm = cxlhdm->regs.hdm_decoder;
+	u32 ctrl;
+	int i;
+
+	if (!is_cxl_endpoint(cxlhdm->port))
+		return false;
+
+	if (!hdm)
+		return true;
+
+	/*
+	 * If any decoders are committed already, there should not be any
+	 * emulated DVSEC decoders.
+	 */
+	for (i = 0; i < cxlhdm->decoder_count; i++) {
+		ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(i));
+		if (FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMITTED, ctrl))
+			return false;
+	}
+
+	return true;
+}
+
 static int init_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld,
 			    int *target_map, void __iomem *hdm, int which,
-			    u64 *dpa_base)
+			    u64 *dpa_base, struct cxl_endpoint_dvsec_info *info)
 {
 	struct cxl_endpoint_decoder *cxled = NULL;
 	u64 size, base, skip, dpa_size;
@@ -703,6 +780,9 @@ static int init_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld,
 		unsigned char target_id[8];
 	} target_list;
 
+	if (should_emulate_decoders(port))
+		return cxl_setup_hdm_decoder_from_dvsec(port, cxld, which, info);
+
 	if (is_endpoint_decoder(&cxld->dev))
 		cxled = to_cxl_endpoint_decoder(&cxld->dev);
 
@@ -726,6 +806,9 @@ static int init_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld,
 		.end = base + size - 1,
 	};
 
+	if (cxled && !committed && range_len(&info->dvsec_range[which]))
+		return cxl_setup_hdm_decoder_from_dvsec(port, cxld, which, info);
+
 	/* decoders are enabled if committed */
 	if (committed) {
 		cxld->flags |= CXL_DECODER_F_ENABLE;
@@ -798,18 +881,15 @@ static int init_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld,
 	return 0;
 }
 
-/**
- * devm_cxl_enumerate_decoders - add decoder objects per HDM register set
- * @cxlhdm: Structure to populate with HDM capabilities
- */
-int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm)
+static void cxl_settle_decoders(struct cxl_hdm *cxlhdm)
 {
 	void __iomem *hdm = cxlhdm->regs.hdm_decoder;
-	struct cxl_port *port = cxlhdm->port;
-	int i, committed;
-	u64 dpa_base = 0;
+	int committed, i;
 	u32 ctrl;
 
+	if (!hdm)
+		return;
+
 	/*
 	 * Since the register resource was recently claimed via request_region()
 	 * be careful about trusting the "not-committed" status until the commit
@@ -826,6 +906,22 @@ int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm)
 	/* ensure that future checks of committed can be trusted */
 	if (committed != cxlhdm->decoder_count)
 		msleep(20);
+}
+
+/**
+ * devm_cxl_enumerate_decoders - add decoder objects per HDM register set
+ * @cxlhdm: Structure to populate with HDM capabilities
+ * @info: cached DVSEC range register info
+ */
+int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm,
+				struct cxl_endpoint_dvsec_info *info)
+{
+	void __iomem *hdm = cxlhdm->regs.hdm_decoder;
+	struct cxl_port *port = cxlhdm->port;
+	int i;
+	u64 dpa_base = 0;
+
+	cxl_settle_decoders(cxlhdm);
 
 	for (i = 0; i < cxlhdm->decoder_count; i++) {
 		int target_map[CXL_DECODER_MAX_INTERLEAVE] = { 0 };
@@ -856,7 +952,8 @@ int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm)
 			cxld = &cxlsd->cxld;
 		}
 
-		rc = init_hdm_decoder(port, cxld, target_map, hdm, i, &dpa_base);
+		rc = init_hdm_decoder(port, cxld, target_map, hdm, i,
+				      &dpa_base, info);
 		if (rc) {
 			dev_warn(&port->dev,
 				 "Failed to initialize decoder%d.%d\n",
diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
index 2b463f107cb5..dd3c37dafdac 100644
--- a/drivers/cxl/core/pci.c
+++ b/drivers/cxl/core/pci.c
@@ -142,11 +142,10 @@ int cxl_await_media_ready(struct cxl_dev_state *cxlds)
 }
 EXPORT_SYMBOL_NS_GPL(cxl_await_media_ready, CXL);
 
-static int wait_for_valid(struct cxl_dev_state *cxlds)
+static int wait_for_valid(struct pci_dev *pdev, int d)
 {
-	struct pci_dev *pdev = to_pci_dev(cxlds->dev);
-	int d = cxlds->cxl_dvsec, rc;
 	u32 val;
+	int rc;
 
 	/*
 	 * Memory_Info_Valid: When set, indicates that the CXL Range 1 Size high
@@ -225,8 +224,6 @@ static int dvsec_range_allowed(struct device *dev, void *arg)
 
 	cxld = to_cxl_decoder(dev);
 
-	if (!(cxld->flags & CXL_DECODER_F_LOCK))
-		return 0;
 	if (!(cxld->flags & CXL_DECODER_F_RAM))
 		return 0;
 
@@ -256,36 +253,145 @@ static int devm_cxl_enable_hdm(struct device *host, struct cxl_hdm *cxlhdm)
 	return devm_add_action_or_reset(host, disable_hdm, cxlhdm);
 }
 
-static bool __cxl_hdm_decode_init(struct cxl_dev_state *cxlds,
-				  struct cxl_hdm *cxlhdm,
-				  struct cxl_endpoint_dvsec_info *info)
+int cxl_dvsec_rr_decode(struct device *dev, int d,
+			struct cxl_endpoint_dvsec_info *info)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	int hdm_count, rc, i, ranges = 0;
+	u16 cap, ctrl;
+
+	if (!d) {
+		dev_dbg(dev, "No DVSEC Capability\n");
+		return -ENXIO;
+	}
+
+	rc = pci_read_config_word(pdev, d + CXL_DVSEC_CAP_OFFSET, &cap);
+	if (rc)
+		return rc;
+
+	rc = pci_read_config_word(pdev, d + CXL_DVSEC_CTRL_OFFSET, &ctrl);
+	if (rc)
+		return rc;
+
+	if (!(cap & CXL_DVSEC_MEM_CAPABLE)) {
+		dev_dbg(dev, "Not MEM Capable\n");
+		return -ENXIO;
+	}
+
+	/*
+	 * It is not allowed by spec for MEM.capable to be set and have 0 legacy
+	 * HDM decoders (values > 2 are also undefined as of CXL 2.0). As this
+	 * driver is for a spec defined class code which must be CXL.mem
+	 * capable, there is no point in continuing to enable CXL.mem.
+	 */
+	hdm_count = FIELD_GET(CXL_DVSEC_HDM_COUNT_MASK, cap);
+	if (!hdm_count || hdm_count > 2)
+		return -EINVAL;
+
+	rc = wait_for_valid(pdev, d);
+	if (rc) {
+		dev_dbg(dev, "Failure awaiting MEM_INFO_VALID (%d)\n", rc);
+		return rc;
+	}
+
+	/*
+	 * The current DVSEC values are moot if the memory capability is
+	 * disabled, and they will remain moot after the HDM Decoder
+	 * capability is enabled.
+	 */
+	info->mem_enabled = FIELD_GET(CXL_DVSEC_MEM_ENABLE, ctrl);
+	if (!info->mem_enabled)
+		return 0;
+
+	for (i = 0; i < hdm_count; i++) {
+		u64 base, size;
+		u32 temp;
+
+		rc = pci_read_config_dword(
+			pdev, d + CXL_DVSEC_RANGE_SIZE_HIGH(i), &temp);
+		if (rc)
+			return rc;
+
+		size = (u64)temp << 32;
+
+		rc = pci_read_config_dword(
+			pdev, d + CXL_DVSEC_RANGE_SIZE_LOW(i), &temp);
+		if (rc)
+			return rc;
+
+		size |= temp & CXL_DVSEC_MEM_SIZE_LOW_MASK;
+		if (!size) {
+			info->dvsec_range[i] = (struct range) {
+				.start = 0,
+				.end = CXL_RESOURCE_NONE,
+			};
+			continue;
+		}
+
+		rc = pci_read_config_dword(
+			pdev, d + CXL_DVSEC_RANGE_BASE_HIGH(i), &temp);
+		if (rc)
+			return rc;
+
+		base = (u64)temp << 32;
+
+		rc = pci_read_config_dword(
+			pdev, d + CXL_DVSEC_RANGE_BASE_LOW(i), &temp);
+		if (rc)
+			return rc;
+
+		base |= temp & CXL_DVSEC_MEM_BASE_LOW_MASK;
+
+		info->dvsec_range[i] = (struct range) {
+			.start = base,
+			.end = base + size - 1
+		};
+
+		ranges++;
+	}
+
+	info->ranges = ranges;
+
+	return 0;
+}
+EXPORT_SYMBOL_NS_GPL(cxl_dvsec_rr_decode, CXL);
+
+/**
+ * cxl_hdm_decode_init() - Setup HDM decoding for the endpoint
+ * @cxlds: Device state
+ * @cxlhdm: Mapped HDM decoder Capability
+ * @info: Cached DVSEC range registers info
+ *
+ * Try to enable the endpoint's HDM Decoder Capability
+ */
+int cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm *cxlhdm,
+			struct cxl_endpoint_dvsec_info *info)
 {
 	void __iomem *hdm = cxlhdm->regs.hdm_decoder;
 	struct cxl_port *port = cxlhdm->port;
 	struct device *dev = cxlds->dev;
 	struct cxl_port *root;
 	int i, rc, allowed;
-	u32 global_ctrl;
+	u32 global_ctrl = 0;
 
-	global_ctrl = readl(hdm + CXL_HDM_DECODER_CTRL_OFFSET);
+	if (hdm)
+		global_ctrl = readl(hdm + CXL_HDM_DECODER_CTRL_OFFSET);
 
 	/*
 	 * If the HDM Decoder Capability is already enabled then assume
 	 * that some other agent like platform firmware set it up.
 	 */
-	if (global_ctrl & CXL_HDM_DECODER_ENABLE) {
-		rc = devm_cxl_enable_mem(&port->dev, cxlds);
-		if (rc)
-			return false;
-		return true;
-	}
+	if (global_ctrl & CXL_HDM_DECODER_ENABLE || (!hdm && info->mem_enabled))
+		return devm_cxl_enable_mem(&port->dev, cxlds);
+	else if (!hdm)
+		return -ENODEV;
 
 	root = to_cxl_port(port->dev.parent);
 	while (!is_cxl_root(root) && is_cxl_port(root->dev.parent))
 		root = to_cxl_port(root->dev.parent);
 	if (!is_cxl_root(root)) {
 		dev_err(dev, "Failed to acquire root port for HDM enable\n");
-		return false;
+		return -ENODEV;
 	}
 
 	for (i = 0, allowed = 0; info->mem_enabled && i < info->ranges; i++) {
@@ -317,133 +423,13 @@ static bool __cxl_hdm_decode_init(struct cxl_dev_state *cxlds,
 	 * Decoder Capability Enable.
 	 */
 	if (info->mem_enabled)
-		return false;
+		return 0;
 
 	rc = devm_cxl_enable_hdm(&port->dev, cxlhdm);
-	if (rc)
-		return false;
-
-	rc = devm_cxl_enable_mem(&port->dev, cxlds);
-	if (rc)
-		return false;
-
-	return true;
-}
-
-/**
- * cxl_hdm_decode_init() - Setup HDM decoding for the endpoint
- * @cxlds: Device state
- * @cxlhdm: Mapped HDM decoder Capability
- *
- * Try to enable the endpoint's HDM Decoder Capability
- */
-int cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm *cxlhdm)
-{
-	struct pci_dev *pdev = to_pci_dev(cxlds->dev);
-	struct cxl_endpoint_dvsec_info info = { 0 };
-	int hdm_count, rc, i, ranges = 0;
-	struct device *dev = &pdev->dev;
-	int d = cxlds->cxl_dvsec;
-	u16 cap, ctrl;
-
-	if (!d) {
-		dev_dbg(dev, "No DVSEC Capability\n");
-		return -ENXIO;
-	}
-
-	rc = pci_read_config_word(pdev, d + CXL_DVSEC_CAP_OFFSET, &cap);
 	if (rc)
 		return rc;
 
-	rc = pci_read_config_word(pdev, d + CXL_DVSEC_CTRL_OFFSET, &ctrl);
-	if (rc)
-		return rc;
-
-	if (!(cap & CXL_DVSEC_MEM_CAPABLE)) {
-		dev_dbg(dev, "Not MEM Capable\n");
-		return -ENXIO;
-	}
-
-	/*
-	 * It is not allowed by spec for MEM.capable to be set and have 0 legacy
-	 * HDM decoders (values > 2 are also undefined as of CXL 2.0). As this
-	 * driver is for a spec defined class code which must be CXL.mem
-	 * capable, there is no point in continuing to enable CXL.mem.
-	 */
-	hdm_count = FIELD_GET(CXL_DVSEC_HDM_COUNT_MASK, cap);
-	if (!hdm_count || hdm_count > 2)
-		return -EINVAL;
-
-	rc = wait_for_valid(cxlds);
-	if (rc) {
-		dev_dbg(dev, "Failure awaiting MEM_INFO_VALID (%d)\n", rc);
-		return rc;
-	}
-
-	/*
-	 * The current DVSEC values are moot if the memory capability is
-	 * disabled, and they will remain moot after the HDM Decoder
-	 * capability is enabled.
-	 */
-	info.mem_enabled = FIELD_GET(CXL_DVSEC_MEM_ENABLE, ctrl);
-	if (!info.mem_enabled)
-		goto hdm_init;
-
-	for (i = 0; i < hdm_count; i++) {
-		u64 base, size;
-		u32 temp;
-
-		rc = pci_read_config_dword(
-			pdev, d + CXL_DVSEC_RANGE_SIZE_HIGH(i), &temp);
-		if (rc)
-			return rc;
-
-		size = (u64)temp << 32;
-
-		rc = pci_read_config_dword(
-			pdev, d + CXL_DVSEC_RANGE_SIZE_LOW(i), &temp);
-		if (rc)
-			return rc;
-
-		size |= temp & CXL_DVSEC_MEM_SIZE_LOW_MASK;
-
-		rc = pci_read_config_dword(
-			pdev, d + CXL_DVSEC_RANGE_BASE_HIGH(i), &temp);
-		if (rc)
-			return rc;
-
-		base = (u64)temp << 32;
-
-		rc = pci_read_config_dword(
-			pdev, d + CXL_DVSEC_RANGE_BASE_LOW(i), &temp);
-		if (rc)
-			return rc;
-
-		base |= temp & CXL_DVSEC_MEM_BASE_LOW_MASK;
-
-		info.dvsec_range[i] = (struct range) {
-			.start = base,
-			.end = base + size - 1
-		};
-
-		if (size)
-			ranges++;
-	}
-
-	info.ranges = ranges;
-
-	/*
-	 * If DVSEC ranges are being used instead of HDM decoder registers there
-	 * is no use in trying to manage those.
-	 */
-hdm_init:
-	if (!__cxl_hdm_decode_init(cxlds, cxlhdm, &info)) {
-		dev_err(dev,
-			"Legacy range registers configuration prevents HDM operation.\n");
-		return -EBUSY;
-	}
-
-	return 0;
+	return devm_cxl_enable_mem(&port->dev, cxlds);
 }
 EXPORT_SYMBOL_NS_GPL(cxl_hdm_decode_init, CXL);
 
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 64258442622a..d853a0238ad7 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -693,10 +693,26 @@ int cxl_decoder_add_locked(struct cxl_decoder *cxld, int *target_map);
 int cxl_decoder_autoremove(struct device *host, struct cxl_decoder *cxld);
 int cxl_endpoint_autoremove(struct cxl_memdev *cxlmd, struct cxl_port *endpoint);
 
+/**
+ * struct cxl_endpoint_dvsec_info - Cached DVSEC info
+ * @mem_enabled: cached value of mem_enabled in the DVSEC, PCIE_DEVICE
+ * @ranges: Number of active HDM ranges this device uses.
+ * @dvsec_range: cached attributes of the ranges in the DVSEC, PCIE_DEVICE
+ */
+struct cxl_endpoint_dvsec_info {
+	bool mem_enabled;
+	int ranges;
+	struct range dvsec_range[2];
+};
+
 struct cxl_hdm;
-struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port);
-int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm);
+struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port,
+				   struct cxl_endpoint_dvsec_info *info);
+int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm,
+				struct cxl_endpoint_dvsec_info *info);
 int devm_cxl_add_passthrough_decoder(struct cxl_port *port);
+int cxl_dvsec_rr_decode(struct device *dev, int dvsec,
+			struct cxl_endpoint_dvsec_info *info);
 
 bool is_cxl_region(struct device *dev);
 
diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
index 64ede1a06eaf..c6c560c67a8a 100644
--- a/drivers/cxl/cxlmem.h
+++ b/drivers/cxl/cxlmem.h
@@ -187,18 +187,6 @@ static inline int cxl_mbox_cmd_rc2errno(struct cxl_mbox_cmd *mbox_cmd)
  */
 #define CXL_CAPACITY_MULTIPLIER SZ_256M
 
-/**
- * struct cxl_endpoint_dvsec_info - Cached DVSEC info
- * @mem_enabled: cached value of mem_enabled in the DVSEC, PCIE_DEVICE
- * @ranges: Number of active HDM ranges this device uses.
- * @dvsec_range: cached attributes of the ranges in the DVSEC, PCIE_DEVICE
- */
-struct cxl_endpoint_dvsec_info {
-	bool mem_enabled;
-	int ranges;
-	struct range dvsec_range[2];
-};
-
 /**
  * Event Interrupt Policy
  *
diff --git a/drivers/cxl/cxlpci.h b/drivers/cxl/cxlpci.h
index a8ea04f536ab..be6a2ef3cce3 100644
--- a/drivers/cxl/cxlpci.h
+++ b/drivers/cxl/cxlpci.h
@@ -70,7 +70,8 @@ enum cxl_regloc_type {
 
 int devm_cxl_port_enumerate_dports(struct cxl_port *port);
 struct cxl_dev_state;
-int cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm *cxlhdm);
+int cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm *cxlhdm,
+			struct cxl_endpoint_dvsec_info *info);
 void read_cdat_data(struct cxl_port *port);
 void cxl_cor_error_detected(struct pci_dev *pdev);
 pci_ers_result_t cxl_error_detected(struct pci_dev *pdev,
diff --git a/drivers/cxl/port.c b/drivers/cxl/port.c
index d6c151dabaa7..1049bb5ea496 100644
--- a/drivers/cxl/port.c
+++ b/drivers/cxl/port.c
@@ -69,22 +69,27 @@ static int cxl_switch_port_probe(struct cxl_port *port)
 	if (rc == 1)
 		return devm_cxl_add_passthrough_decoder(port);
 
-	cxlhdm = devm_cxl_setup_hdm(port);
+	cxlhdm = devm_cxl_setup_hdm(port, NULL);
 	if (IS_ERR(cxlhdm))
 		return PTR_ERR(cxlhdm);
 
-	return devm_cxl_enumerate_decoders(cxlhdm);
+	return devm_cxl_enumerate_decoders(cxlhdm, NULL);
 }
 
 static int cxl_endpoint_port_probe(struct cxl_port *port)
 {
 	struct cxl_memdev *cxlmd = to_cxl_memdev(port->uport);
+	struct cxl_endpoint_dvsec_info info = { 0 };
 	struct cxl_dev_state *cxlds = cxlmd->cxlds;
 	struct cxl_hdm *cxlhdm;
 	struct cxl_port *root;
 	int rc;
 
-	cxlhdm = devm_cxl_setup_hdm(port);
+	rc = cxl_dvsec_rr_decode(cxlds->dev, cxlds->cxl_dvsec, &info);
+	if (rc < 0)
+		return rc;
+
+	cxlhdm = devm_cxl_setup_hdm(port, &info);
 	if (IS_ERR(cxlhdm))
 		return PTR_ERR(cxlhdm);
 
@@ -96,7 +101,7 @@ static int cxl_endpoint_port_probe(struct cxl_port *port)
 	if (rc)
 		return rc;
 
-	rc = cxl_hdm_decode_init(cxlds, cxlhdm);
+	rc = cxl_hdm_decode_init(cxlds, cxlhdm, &info);
 	if (rc)
 		return rc;
 
@@ -106,7 +111,7 @@ static int cxl_endpoint_port_probe(struct cxl_port *port)
 		return rc;
 	}
 
-	rc = devm_cxl_enumerate_decoders(cxlhdm);
+	rc = devm_cxl_enumerate_decoders(cxlhdm, &info);
 	if (rc)
 		return rc;
 
diff --git a/tools/testing/cxl/Kbuild b/tools/testing/cxl/Kbuild
index 37f77ac9b917..fba7bec96acd 100644
--- a/tools/testing/cxl/Kbuild
+++ b/tools/testing/cxl/Kbuild
@@ -10,6 +10,7 @@ ldflags-y += --wrap=devm_cxl_add_passthrough_decoder
 ldflags-y += --wrap=devm_cxl_enumerate_decoders
 ldflags-y += --wrap=cxl_await_media_ready
 ldflags-y += --wrap=cxl_hdm_decode_init
+ldflags-y += --wrap=cxl_dvsec_rr_decode
 ldflags-y += --wrap=cxl_rcrb_to_component
 
 DRIVERS := ../../../drivers
diff --git a/tools/testing/cxl/test/cxl.c b/tools/testing/cxl/test/cxl.c
index 41c5d735308e..bf00dc52fe96 100644
--- a/tools/testing/cxl/test/cxl.c
+++ b/tools/testing/cxl/test/cxl.c
@@ -620,7 +620,8 @@ static struct acpi_pci_root *mock_acpi_pci_find_root(acpi_handle handle)
 	return &mock_pci_root[host_bridge_index(adev)];
 }
 
-static struct cxl_hdm *mock_cxl_setup_hdm(struct cxl_port *port)
+static struct cxl_hdm *mock_cxl_setup_hdm(struct cxl_port *port,
+					  struct cxl_endpoint_dvsec_info *info)
 {
 	struct cxl_hdm *cxlhdm = devm_kzalloc(&port->dev, sizeof(*cxlhdm), GFP_KERNEL);
 
@@ -839,7 +840,8 @@ static void mock_init_hdm_decoder(struct cxl_decoder *cxld)
 	}
 }
 
-static int mock_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm)
+static int mock_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm,
+				       struct cxl_endpoint_dvsec_info *info)
 {
 	struct cxl_port *port = cxlhdm->port;
 	struct cxl_port *parent_port = to_cxl_port(port->dev.parent);
diff --git a/tools/testing/cxl/test/mock.c b/tools/testing/cxl/test/mock.c
index 5dface08e0de..c4e53f22e421 100644
--- a/tools/testing/cxl/test/mock.c
+++ b/tools/testing/cxl/test/mock.c
@@ -131,16 +131,18 @@ __wrap_nvdimm_bus_register(struct device *dev,
 }
 EXPORT_SYMBOL_GPL(__wrap_nvdimm_bus_register);
 
-struct cxl_hdm *__wrap_devm_cxl_setup_hdm(struct cxl_port *port)
+struct cxl_hdm *__wrap_devm_cxl_setup_hdm(struct cxl_port *port,
+					  struct cxl_endpoint_dvsec_info *info)
+
 {
 	int index;
 	struct cxl_hdm *cxlhdm;
 	struct cxl_mock_ops *ops = get_cxl_mock_ops(&index);
 
 	if (ops && ops->is_mock_port(port->uport))
-		cxlhdm = ops->devm_cxl_setup_hdm(port);
+		cxlhdm = ops->devm_cxl_setup_hdm(port, info);
 	else
-		cxlhdm = devm_cxl_setup_hdm(port);
+		cxlhdm = devm_cxl_setup_hdm(port, info);
 	put_cxl_mock_ops(index);
 
 	return cxlhdm;
@@ -162,16 +164,17 @@ int __wrap_devm_cxl_add_passthrough_decoder(struct cxl_port *port)
 }
 EXPORT_SYMBOL_NS_GPL(__wrap_devm_cxl_add_passthrough_decoder, CXL);
 
-int __wrap_devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm)
+int __wrap_devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm,
+				       struct cxl_endpoint_dvsec_info *info)
 {
 	int rc, index;
 	struct cxl_port *port = cxlhdm->port;
 	struct cxl_mock_ops *ops = get_cxl_mock_ops(&index);
 
 	if (ops && ops->is_mock_port(port->uport))
-		rc = ops->devm_cxl_enumerate_decoders(cxlhdm);
+		rc = ops->devm_cxl_enumerate_decoders(cxlhdm, info);
 	else
-		rc = devm_cxl_enumerate_decoders(cxlhdm);
+		rc = devm_cxl_enumerate_decoders(cxlhdm, info);
 	put_cxl_mock_ops(index);
 
 	return rc;
@@ -209,7 +212,8 @@ int __wrap_cxl_await_media_ready(struct cxl_dev_state *cxlds)
 EXPORT_SYMBOL_NS_GPL(__wrap_cxl_await_media_ready, CXL);
 
 int __wrap_cxl_hdm_decode_init(struct cxl_dev_state *cxlds,
-			       struct cxl_hdm *cxlhdm)
+			       struct cxl_hdm *cxlhdm,
+			       struct cxl_endpoint_dvsec_info *info)
 {
 	int rc = 0, index;
 	struct cxl_mock_ops *ops = get_cxl_mock_ops(&index);
@@ -217,13 +221,29 @@ int __wrap_cxl_hdm_decode_init(struct cxl_dev_state *cxlds,
 	if (ops && ops->is_mock_dev(cxlds->dev))
 		rc = 0;
 	else
-		rc = cxl_hdm_decode_init(cxlds, cxlhdm);
+		rc = cxl_hdm_decode_init(cxlds, cxlhdm, info);
 	put_cxl_mock_ops(index);
 
 	return rc;
 }
 EXPORT_SYMBOL_NS_GPL(__wrap_cxl_hdm_decode_init, CXL);
 
+int __wrap_cxl_dvsec_rr_decode(struct device *dev, int dvsec,
+			       struct cxl_endpoint_dvsec_info *info)
+{
+	int rc = 0, index;
+	struct cxl_mock_ops *ops = get_cxl_mock_ops(&index);
+
+	if (ops && ops->is_mock_dev(dev))
+		rc = 0;
+	else
+		rc = cxl_dvsec_rr_decode(dev, dvsec, info);
+	put_cxl_mock_ops(index);
+
+	return rc;
+}
+EXPORT_SYMBOL_NS_GPL(__wrap_cxl_dvsec_rr_decode, CXL);
+
 resource_size_t __wrap_cxl_rcrb_to_component(struct device *dev,
 					     resource_size_t rcrb,
 					     enum cxl_rcrb which)
diff --git a/tools/testing/cxl/test/mock.h b/tools/testing/cxl/test/mock.h
index ef33f159375e..bef8817b01f2 100644
--- a/tools/testing/cxl/test/mock.h
+++ b/tools/testing/cxl/test/mock.h
@@ -23,9 +23,11 @@ struct cxl_mock_ops {
 	bool (*is_mock_port)(struct device *dev);
 	bool (*is_mock_dev)(struct device *dev);
 	int (*devm_cxl_port_enumerate_dports)(struct cxl_port *port);
-	struct cxl_hdm *(*devm_cxl_setup_hdm)(struct cxl_port *port);
+	struct cxl_hdm *(*devm_cxl_setup_hdm)(
+		struct cxl_port *port, struct cxl_endpoint_dvsec_info *info);
 	int (*devm_cxl_add_passthrough_decoder)(struct cxl_port *port);
-	int (*devm_cxl_enumerate_decoders)(struct cxl_hdm *hdm);
+	int (*devm_cxl_enumerate_decoders)(
+		struct cxl_hdm *hdm, struct cxl_endpoint_dvsec_info *info);
 };
 
 void register_cxl_mock_ops(struct cxl_mock_ops *ops);