diff --git a/drivers/cxl/core/core.h b/drivers/cxl/core/core.h
index 91abeffbe985..119b12362977 100644
--- a/drivers/cxl/core/core.h
+++ b/drivers/cxl/core/core.h
@@ -4,6 +4,8 @@
 #ifndef __CXL_CORE_H__
 #define __CXL_CORE_H__
 
+#include <cxlmem.h>
+
 extern const struct device_type cxl_nvdimm_bridge_type;
 extern const struct device_type cxl_nvdimm_type;
 extern const struct device_type cxl_pmu_type;
@@ -28,6 +30,8 @@ void cxl_decoder_kill_region(struct cxl_endpoint_decoder *cxled);
 int cxl_region_init(void);
 void cxl_region_exit(void);
 int cxl_get_poison_by_endpoint(struct cxl_port *port);
+int cxl_ed_add_one_extent(struct cxl_endpoint_decoder *cxled,
+			  struct cxl_dc_extent *dc_extent);
 #else
 static inline int cxl_get_poison_by_endpoint(struct cxl_port *port)
 {
@@ -43,6 +47,11 @@ static inline int cxl_region_init(void)
 static inline void cxl_region_exit(void)
 {
 }
+static inline int cxl_ed_add_one_extent(struct cxl_endpoint_decoder *cxled,
+					struct cxl_dc_extent *dc_extent)
+{
+	return 0;
+}
 #define CXL_REGION_ATTR(x) NULL
 #define CXL_REGION_TYPE(x) NULL
 #define SET_CXL_REGION_ATTR(x)
diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
index 58b31fa47b93..9e33a0976828 100644
--- a/drivers/cxl/core/mbox.c
+++ b/drivers/cxl/core/mbox.c
@@ -870,6 +870,53 @@ int cxl_enumerate_cmds(struct cxl_memdev_state *mds)
 }
 EXPORT_SYMBOL_NS_GPL(cxl_enumerate_cmds, CXL);
 
+static int cxl_validate_extent(struct cxl_memdev_state *mds,
+			       struct cxl_dc_extent *dc_extent)
+{
+	struct device *dev = mds->cxlds.dev;
+	uint64_t start, len;
+
+	start = le64_to_cpu(dc_extent->start_dpa);
+	len = le64_to_cpu(dc_extent->length);
+
+	/* Extents must not cross region boundary's */
+	for (int i = 0; i < mds->nr_dc_region; i++) {
+		struct cxl_dc_region_info *dcr = &mds->dc_region[i];
+
+		if (dcr->base <= start &&
+		    (start + len) <= (dcr->base + dcr->decode_len)) {
+			dev_dbg(dev, "DC extent DPA %#llx - %#llx (DCR:%d:%#llx)\n",
+				start, start + len - 1, i, start - dcr->base);
+			return 0;
+		}
+	}
+
+	dev_err_ratelimited(dev,
+			    "DC extent DPA %#llx - %#llx is not in any DC region\n",
+			    start, start + len - 1);
+	return -EINVAL;
+}
+
+static bool cxl_dc_extent_in_ed(struct cxl_endpoint_decoder *cxled,
+				struct cxl_dc_extent *extent)
+{
+	uint64_t start = le64_to_cpu(extent->start_dpa);
+	uint64_t length = le64_to_cpu(extent->length);
+	struct range ext_range = (struct range){
+		.start = start,
+		.end = start + length - 1,
+	};
+	struct range ed_range = (struct range) {
+		.start = cxled->dpa_res->start,
+		.end = cxled->dpa_res->end,
+	};
+
+	dev_dbg(&cxled->cxld.dev, "Checking ED (%pr) for extent DPA:%#llx LEN:%#llx\n",
+		cxled->dpa_res, start, length);
+
+	return range_contains(&ed_range, &ext_range);
+}
+
 void cxl_event_trace_record(const struct cxl_memdev *cxlmd,
 			    enum cxl_event_log_type type,
 			    enum cxl_event_type event_type,
@@ -973,6 +1020,15 @@ static int cxl_clear_event_record(struct cxl_memdev_state *mds,
 	return rc;
 }
 
+static struct cxl_memdev_state *
+cxled_to_mds(struct cxl_endpoint_decoder *cxled)
+{
+	struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
+	struct cxl_dev_state *cxlds = cxlmd->cxlds;
+
+	return container_of(cxlds, struct cxl_memdev_state, cxlds);
+}
+
 static void cxl_mem_get_records_log(struct cxl_memdev_state *mds,
 				    enum cxl_event_log_type type)
 {
@@ -1406,6 +1462,142 @@ int cxl_dev_dynamic_capacity_identify(struct cxl_memdev_state *mds)
 }
 EXPORT_SYMBOL_NS_GPL(cxl_dev_dynamic_capacity_identify, CXL);
 
+static int cxl_dev_get_dc_extent_cnt(struct cxl_memdev_state *mds,
+				     unsigned int *extent_gen_num)
+{
+	struct cxl_mbox_get_dc_extent_in get_dc_extent;
+	struct cxl_mbox_get_dc_extent_out dc_extents;
+	struct cxl_mbox_cmd mbox_cmd;
+	unsigned int count;
+	int rc;
+
+	get_dc_extent = (struct cxl_mbox_get_dc_extent_in) {
+		.extent_cnt = cpu_to_le32(0),
+		.start_extent_index = cpu_to_le32(0),
+	};
+
+	mbox_cmd = (struct cxl_mbox_cmd) {
+		.opcode = CXL_MBOX_OP_GET_DC_EXTENT_LIST,
+		.payload_in = &get_dc_extent,
+		.size_in = sizeof(get_dc_extent),
+		.size_out = sizeof(dc_extents),
+		.payload_out = &dc_extents,
+		.min_out = 1,
+	};
+
+	rc = cxl_internal_send_cmd(mds, &mbox_cmd);
+	if (rc < 0)
+		return rc;
+
+	count = le32_to_cpu(dc_extents.total_extent_cnt);
+	*extent_gen_num = le32_to_cpu(dc_extents.extent_list_num);
+
+	return count;
+}
+
+static int cxl_dev_get_dc_extents(struct cxl_endpoint_decoder *cxled,
+				  unsigned int start_gen_num,
+				  unsigned int exp_cnt)
+{
+	struct cxl_memdev_state *mds = cxled_to_mds(cxled);
+	unsigned int start_index, total_read;
+	struct device *dev = mds->cxlds.dev;
+	struct cxl_mbox_cmd mbox_cmd;
+
+	struct cxl_mbox_get_dc_extent_out *dc_extents __free(kfree) =
+				kvmalloc(mds->payload_size, GFP_KERNEL);
+	if (!dc_extents)
+		return -ENOMEM;
+
+	total_read = 0;
+	start_index = 0;
+	do {
+		unsigned int nr_ext, total_extent_cnt, gen_num;
+		struct cxl_mbox_get_dc_extent_in get_dc_extent;
+		int rc;
+
+		get_dc_extent = (struct cxl_mbox_get_dc_extent_in) {
+			.extent_cnt = cpu_to_le32(exp_cnt - start_index),
+			.start_extent_index = cpu_to_le32(start_index),
+		};
+
+		mbox_cmd = (struct cxl_mbox_cmd) {
+			.opcode = CXL_MBOX_OP_GET_DC_EXTENT_LIST,
+			.payload_in = &get_dc_extent,
+			.size_in = sizeof(get_dc_extent),
+			.size_out = mds->payload_size,
+			.payload_out = dc_extents,
+			.min_out = 1,
+		};
+
+		rc = cxl_internal_send_cmd(mds, &mbox_cmd);
+		if (rc < 0)
+			return rc;
+
+		nr_ext = le32_to_cpu(dc_extents->ret_extent_cnt);
+		total_read += nr_ext;
+		total_extent_cnt = le32_to_cpu(dc_extents->total_extent_cnt);
+		gen_num = le32_to_cpu(dc_extents->extent_list_num);
+
+		dev_dbg(dev, "Get extent list count:%d generation Num:%d\n",
+			total_extent_cnt, gen_num);
+
+		if (gen_num != start_gen_num || exp_cnt != total_extent_cnt) {
+			dev_err(dev, "Possible incomplete extent list; gen %u != %u : cnt %u != %u\n",
+				gen_num, start_gen_num, exp_cnt, total_extent_cnt);
+			return -EIO;
+		}
+
+		for (int i = 0; i < nr_ext ; i++) {
+			dev_dbg(dev, "Processing extent %d/%d\n",
+				start_index + i, exp_cnt);
+			rc = cxl_validate_extent(mds, &dc_extents->extent[i]);
+			if (rc)
+				continue;
+			if (!cxl_dc_extent_in_ed(cxled, &dc_extents->extent[i]))
+				continue;
+			rc = cxl_ed_add_one_extent(cxled, &dc_extents->extent[i]);
+			if (rc)
+				return rc;
+		}
+
+		start_index += nr_ext;
+	} while (exp_cnt > total_read);
+
+	return 0;
+}
+
+/**
+ * cxl_read_dc_extents() - Read any existing extents
+ * @cxled: Endpoint decoder which is part of a region
+ *
+ * Issue the Get Dynamic Capacity Extent List command to the device
+ * and add any existing extents found which belong to this decoder.
+ *
+ * Return: 0 if command was executed successfully, -ERRNO on error.
+ */
+int cxl_read_dc_extents(struct cxl_endpoint_decoder *cxled)
+{
+	struct cxl_memdev_state *mds = cxled_to_mds(cxled);
+	struct device *dev = mds->cxlds.dev;
+	unsigned int extent_gen_num;
+	int rc;
+
+	if (!cxl_dcd_supported(mds)) {
+		dev_dbg(dev, "DCD unsupported\n");
+		return 0;
+	}
+
+	rc = cxl_dev_get_dc_extent_cnt(mds, &extent_gen_num);
+	dev_dbg(mds->cxlds.dev, "Extent count: %d Generation Num: %d\n",
+		rc, extent_gen_num);
+	if (rc <= 0) /* 0 == no records found */
+		return rc;
+
+	return cxl_dev_get_dc_extents(cxled, extent_gen_num, rc);
+}
+EXPORT_SYMBOL_NS_GPL(cxl_read_dc_extents, CXL);
+
 static int add_dpa_res(struct device *dev, struct resource *parent,
 		       struct resource *res, resource_size_t start,
 		       resource_size_t size, const char *type)
diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
index 0d7b09a49dcf..3e563ab29afe 100644
--- a/drivers/cxl/core/region.c
+++ b/drivers/cxl/core/region.c
@@ -1450,6 +1450,13 @@ static int cxl_region_validate_position(struct cxl_region *cxlr,
 	return 0;
 }
 
+/* Callers are expected to ensure cxled has been attached to a region */
+int cxl_ed_add_one_extent(struct cxl_endpoint_decoder *cxled,
+			  struct cxl_dc_extent *dc_extent)
+{
+	return 0;
+}
+
 static int cxl_region_attach_position(struct cxl_region *cxlr,
 				      struct cxl_root_decoder *cxlrd,
 				      struct cxl_endpoint_decoder *cxled,
@@ -2773,6 +2780,22 @@ static int devm_cxl_add_pmem_region(struct cxl_region *cxlr)
 	return rc;
 }
 
+static int cxl_region_read_extents(struct cxl_region *cxlr)
+{
+	struct cxl_region_params *p = &cxlr->params;
+	int i;
+
+	for (i = 0; i < p->nr_targets; i++) {
+		int rc;
+
+		rc = cxl_read_dc_extents(p->targets[i]);
+		if (rc)
+			return rc;
+	}
+
+	return 0;
+}
+
 static void cxlr_dax_unregister(void *_cxlr_dax)
 {
 	struct cxl_dax_region *cxlr_dax = _cxlr_dax;
@@ -2807,6 +2830,12 @@ static int devm_cxl_add_dax_region(struct cxl_region *cxlr)
 	dev_dbg(&cxlr->dev, "%s: register %s\n", dev_name(dev->parent),
 		dev_name(dev));
 
+	if (cxlr->mode == CXL_REGION_DC) {
+		rc = cxl_region_read_extents(cxlr);
+		if (rc)
+			goto err;
+	}
+
 	return devm_add_action_or_reset(&cxlr->dev, cxlr_dax_unregister,
 					cxlr_dax);
 err:
diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
index 01bee6eedff3..8f2d8944d334 100644
--- a/drivers/cxl/cxlmem.h
+++ b/drivers/cxl/cxlmem.h
@@ -604,6 +604,54 @@ enum cxl_opcode {
 	UUID_INIT(0xe1819d9, 0x11a9, 0x400c, 0x81, 0x1f, 0xd6, 0x07, 0x19,     \
 		  0x40, 0x3d, 0x86)
 
+/*
+ * Add Dynamic Capacity Response
+ * CXL rev 3.1 section 8.2.9.9.9.3; Table 8-168 & Table 8-169
+ */
+struct cxl_mbox_dc_response {
+	__le32 extent_list_size;
+	u8 flags;
+	u8 reserved[3];
+	struct updated_extent_list {
+		__le64 dpa_start;
+		__le64 length;
+		u8 reserved[8];
+	} __packed extent_list[];
+} __packed;
+
+/*
+ * CXL rev 3.1 section 8.2.9.2.1.6; Table 8-51
+ */
+#define CXL_DC_EXTENT_TAG_LEN 0x10
+struct cxl_dc_extent {
+	__le64 start_dpa;
+	__le64 length;
+	u8 tag[CXL_DC_EXTENT_TAG_LEN];
+	__le16 shared_extn_seq;
+	u8 reserved[6];
+} __packed;
+
+/*
+ * Get Dynamic Capacity Extent List; Input Payload
+ * CXL rev 3.1 section 8.2.9.9.9.2; Table 8-166
+ */
+struct cxl_mbox_get_dc_extent_in {
+	__le32 extent_cnt;
+	__le32 start_extent_index;
+} __packed;
+
+/*
+ * Get Dynamic Capacity Extent List; Output Payload
+ * CXL rev 3.1 section 8.2.9.9.9.2; Table 8-167
+ */
+struct cxl_mbox_get_dc_extent_out {
+	__le32 ret_extent_cnt;
+	__le32 total_extent_cnt;
+	__le32 extent_list_num;
+	u8 rsvd[4];
+	struct cxl_dc_extent extent[];
+} __packed;
+
 struct cxl_mbox_get_supported_logs {
 	__le16 entries;
 	u8 rsvd[6];
@@ -879,6 +927,7 @@ int cxl_internal_send_cmd(struct cxl_memdev_state *mds,
 			  struct cxl_mbox_cmd *cmd);
 int cxl_dev_state_identify(struct cxl_memdev_state *mds);
 int cxl_dev_dynamic_capacity_identify(struct cxl_memdev_state *mds);
+int cxl_read_dc_extents(struct cxl_endpoint_decoder *cxled);
 int cxl_await_media_ready(struct cxl_dev_state *cxlds);
 int cxl_enumerate_cmds(struct cxl_memdev_state *mds);
 int cxl_mem_create_range_info(struct cxl_memdev_state *mds);
