cxl/mem: Convert partition-info to resources

To date the per-device-partition DPA range information has only been
used for enumeration purposes. In preparation for allocating regions
from available DPA capacity, convert those ranges into DPA-type resource
trees.

With resources and the new add_dpa_res() helper some open coded end
address calculations and debug prints can be cleaned.

The 'cxlds->pmem_res' and 'cxlds->ram_res' resources are child resources
of the total-device DPA space and they in turn will host DPA allocations
from cxl_endpoint_decoder instances (tracked by cxled->dpa_res).

Cc: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/165603878921.551046.8127845916514734142.stgit@dwillia2-xfh
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/cxl/core/mbox.c

@@ -773,15 +773,6 @@ int cxl_dev_state_identify(struct cxl_dev_state *cxlds)
 	cxlds->partition_align_bytes =
 		le64_to_cpu(id.partition_align) * CXL_CAPACITY_MULTIPLIER;
 
-	dev_dbg(cxlds->dev,
-		"Identify Memory Device\n"
-		"     total_bytes = %#llx\n"
-		"     volatile_only_bytes = %#llx\n"
-		"     persistent_only_bytes = %#llx\n"
-		"     partition_align_bytes = %#llx\n",
-		cxlds->total_bytes, cxlds->volatile_only_bytes,
-		cxlds->persistent_only_bytes, cxlds->partition_align_bytes);
-
 	cxlds->lsa_size = le32_to_cpu(id.lsa_size);
 	memcpy(cxlds->firmware_version, id.fw_revision, sizeof(id.fw_revision));
 
@@ -789,42 +780,63 @@ int cxl_dev_state_identify(struct cxl_dev_state *cxlds)
 }
 EXPORT_SYMBOL_NS_GPL(cxl_dev_state_identify, CXL);
 
-int cxl_mem_create_range_info(struct cxl_dev_state *cxlds)
+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)
 {
 	int rc;
 
-	if (cxlds->partition_align_bytes == 0) {
+	res->name = type;
-		cxlds->ram_range.start = 0;
+	res->start = start;
-		cxlds->ram_range.end = cxlds->volatile_only_bytes - 1;
+	res->end = start + size - 1;
-		cxlds->pmem_range.start = cxlds->volatile_only_bytes;
+	res->flags = IORESOURCE_MEM;
-		cxlds->pmem_range.end = cxlds->volatile_only_bytes +
+	if (resource_size(res) == 0) {
-				       cxlds->persistent_only_bytes - 1;
+		dev_dbg(dev, "DPA(%s): no capacity\n", res->name);
 		return 0;
 	}
+	rc = request_resource(parent, res);
+	if (rc) {
+		dev_err(dev, "DPA(%s): failed to track %pr (%d)\n", res->name,
+			res, rc);
+		return rc;
+	}
+
+	dev_dbg(dev, "DPA(%s): %pr\n", res->name, res);
+
+	return 0;
+}
+
+int cxl_mem_create_range_info(struct cxl_dev_state *cxlds)
+{
+	struct device *dev = cxlds->dev;
+	int rc;
+
+	cxlds->dpa_res =
+		(struct resource)DEFINE_RES_MEM(0, cxlds->total_bytes);
+
+	if (cxlds->partition_align_bytes == 0) {
+		rc = add_dpa_res(dev, &cxlds->dpa_res, &cxlds->ram_res, 0,
+				 cxlds->volatile_only_bytes, "ram");
+		if (rc)
+			return rc;
+		return add_dpa_res(dev, &cxlds->dpa_res, &cxlds->pmem_res,
+				   cxlds->volatile_only_bytes,
+				   cxlds->persistent_only_bytes, "pmem");
+	}
 
 	rc = cxl_mem_get_partition_info(cxlds);
 	if (rc) {
-		dev_err(cxlds->dev, "Failed to query partition information\n");
+		dev_err(dev, "Failed to query partition information\n");
 		return rc;
 	}
 
-	dev_dbg(cxlds->dev,
+	rc = add_dpa_res(dev, &cxlds->dpa_res, &cxlds->ram_res, 0,
-		"Get Partition Info\n"
+			 cxlds->active_volatile_bytes, "ram");
-		"     active_volatile_bytes = %#llx\n"
+	if (rc)
-		"     active_persistent_bytes = %#llx\n"
+		return rc;
-		"     next_volatile_bytes = %#llx\n"
+	return add_dpa_res(dev, &cxlds->dpa_res, &cxlds->pmem_res,
-		"     next_persistent_bytes = %#llx\n",
+			   cxlds->active_volatile_bytes,
-		cxlds->active_volatile_bytes, cxlds->active_persistent_bytes,
+			   cxlds->active_persistent_bytes, "pmem");
-		cxlds->next_volatile_bytes, cxlds->next_persistent_bytes);
-
-	cxlds->ram_range.start = 0;
-	cxlds->ram_range.end = cxlds->active_volatile_bytes - 1;
-
-	cxlds->pmem_range.start = cxlds->active_volatile_bytes;
-	cxlds->pmem_range.end =
-		cxlds->active_volatile_bytes + cxlds->active_persistent_bytes - 1;
-
-	return 0;
 }
 EXPORT_SYMBOL_NS_GPL(cxl_mem_create_range_info, CXL);
 

drivers/cxl/core/memdev.c

@@ -68,7 +68,7 @@ static ssize_t ram_size_show(struct device *dev, struct device_attribute *attr,
 {
 	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
 	struct cxl_dev_state *cxlds = cxlmd->cxlds;
-	unsigned long long len = range_len(&cxlds->ram_range);
+	unsigned long long len = resource_size(&cxlds->ram_res);
 
 	return sysfs_emit(buf, "%#llx\n", len);
 }
@@ -81,7 +81,7 @@ static ssize_t pmem_size_show(struct device *dev, struct device_attribute *attr,
 {
 	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
 	struct cxl_dev_state *cxlds = cxlmd->cxlds;
-	unsigned long long len = range_len(&cxlds->pmem_range);
+	unsigned long long len = resource_size(&cxlds->pmem_res);
 
 	return sysfs_emit(buf, "%#llx\n", len);
 }

drivers/cxl/cxlmem.h

@@ -178,8 +178,9 @@ struct cxl_endpoint_dvsec_info {
  * @firmware_version: Firmware version for the memory device.
  * @enabled_cmds: Hardware commands found enabled in CEL.
  * @exclusive_cmds: Commands that are kernel-internal only
- * @pmem_range: Active Persistent memory capacity configuration
+ * @dpa_res: Overall DPA resource tree for the device
- * @ram_range: Active Volatile memory capacity configuration
+ * @pmem_res: Active Persistent memory capacity configuration
+ * @ram_res: Active Volatile memory capacity configuration
  * @total_bytes: sum of all possible capacities
  * @volatile_only_bytes: hard volatile capacity
  * @persistent_only_bytes: hard persistent capacity
@@ -209,8 +210,9 @@ struct cxl_dev_state {
 	DECLARE_BITMAP(enabled_cmds, CXL_MEM_COMMAND_ID_MAX);
 	DECLARE_BITMAP(exclusive_cmds, CXL_MEM_COMMAND_ID_MAX);
 
-	struct range pmem_range;
+	struct resource dpa_res;
-	struct range ram_range;
+	struct resource pmem_res;
+	struct resource ram_res;
 	u64 total_bytes;
 	u64 volatile_only_bytes;
 	u64 persistent_only_bytes;

drivers/cxl/pci.c

@@ -454,7 +454,7 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	if (IS_ERR(cxlmd))
 		return PTR_ERR(cxlmd);
 
-	if (range_len(&cxlds->pmem_range) && IS_ENABLED(CONFIG_CXL_PMEM))
+	if (resource_size(&cxlds->pmem_res) && IS_ENABLED(CONFIG_CXL_PMEM))
 		rc = devm_cxl_add_nvdimm(&pdev->dev, cxlmd);
 
 	return rc;

tools/testing/cxl/test/mem.c

@@ -282,7 +282,7 @@ static int cxl_mock_mem_probe(struct platform_device *pdev)
 	if (IS_ERR(cxlmd))
 		return PTR_ERR(cxlmd);
 
-	if (range_len(&cxlds->pmem_range) && IS_ENABLED(CONFIG_CXL_PMEM))
+	if (resource_size(&cxlds->pmem_res) && IS_ENABLED(CONFIG_CXL_PMEM))
 		rc = devm_cxl_add_nvdimm(dev, cxlmd);
 
 	return 0;