tools/testing/cxl: Add partition support

In support of testing DPA allocation mechanisms in the CXL core, the
cxl_test environment needs to support establishing and retrieving the
'pmem partition boundary.

Replace the platform_device_add_resources() method for delineating DPA
within an endpoint with an emulated DEV_SIZE amount of partitionable
capacity. Set DEV_SIZE such that an endpoint has enough capacity to
simultaneously participate in 8 distinct regions.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/165603887411.551046.13234212587991192347.stgit@dwillia2-xfhSigned-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/cxl/core/mbox.c

@@ -718,12 +718,7 @@ EXPORT_SYMBOL_NS_GPL(cxl_enumerate_cmds, CXL);
  */
 static int cxl_mem_get_partition_info(struct cxl_dev_state *cxlds)
 {
-	struct cxl_mbox_get_partition_info {
-		__le64 active_volatile_cap;
-		__le64 active_persistent_cap;
-		__le64 next_volatile_cap;
-		__le64 next_persistent_cap;
-	} __packed pi;
+	struct cxl_mbox_get_partition_info pi;
 	int rc;
 
 	rc = cxl_mbox_send_cmd(cxlds, CXL_MBOX_OP_GET_PARTITION_INFO, NULL, 0,

drivers/cxl/cxlmem.h

@@ -301,6 +301,13 @@ struct cxl_mbox_identify {
 	u8 qos_telemetry_caps;
 } __packed;
 
+struct cxl_mbox_get_partition_info {
+	__le64 active_volatile_cap;
+	__le64 active_persistent_cap;
+	__le64 next_volatile_cap;
+	__le64 next_persistent_cap;
+} __packed;
+
 struct cxl_mbox_get_lsa {
 	__le32 offset;
 	__le32 length;

tools/testing/cxl/test/cxl.c

@@ -569,44 +569,6 @@ static void mock_companion(struct acpi_device *adev, struct device *dev)
 #define SZ_512G (SZ_64G * 8)
 #endif
 
-static struct platform_device *alloc_memdev(int id)
-{
-	struct resource res[] = {
-		[0] = {
-			.flags = IORESOURCE_MEM,
-		},
-		[1] = {
-			.flags = IORESOURCE_MEM,
-			.desc = IORES_DESC_PERSISTENT_MEMORY,
-		},
-	};
-	struct platform_device *pdev;
-	int i, rc;
-
-	for (i = 0; i < ARRAY_SIZE(res); i++) {
-		struct cxl_mock_res *r = alloc_mock_res(SZ_256M);
-
-		if (!r)
-			return NULL;
-		res[i].start = r->range.start;
-		res[i].end = r->range.end;
-	}
-
-	pdev = platform_device_alloc("cxl_mem", id);
-	if (!pdev)
-		return NULL;
-
-	rc = platform_device_add_resources(pdev, res, ARRAY_SIZE(res));
-	if (rc)
-		goto err;
-
-	return pdev;
-
-err:
-	platform_device_put(pdev);
-	return NULL;
-}
-
 static __init int cxl_test_init(void)
 {
 	int rc, i;
@@ -709,7 +671,7 @@ static __init int cxl_test_init(void)
 		struct platform_device *dport = cxl_switch_dport[i];
 		struct platform_device *pdev;
 
-		pdev = alloc_memdev(i);
+		pdev = platform_device_alloc("cxl_mem", i);
 		if (!pdev)
 			goto err_mem;
 		pdev->dev.parent = &dport->dev;

tools/testing/cxl/test/mem.c

@@ -10,6 +10,7 @@
 #include <cxlmem.h>
 
 #define LSA_SIZE SZ_128K
+#define DEV_SIZE SZ_2G
 #define EFFECT(x) (1U << x)
 
 static struct cxl_cel_entry mock_cel[] = {
@@ -25,6 +26,10 @@ static struct cxl_cel_entry mock_cel[] = {
 		.opcode = cpu_to_le16(CXL_MBOX_OP_GET_LSA),
 		.effect = cpu_to_le16(0),
 	},
+	{
+		.opcode = cpu_to_le16(CXL_MBOX_OP_GET_PARTITION_INFO),
+		.effect = cpu_to_le16(0),
+	},
 	{
 		.opcode = cpu_to_le16(CXL_MBOX_OP_SET_LSA),
 		.effect = cpu_to_le16(EFFECT(1) | EFFECT(2)),
@@ -97,42 +102,37 @@ static int mock_get_log(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd)
 
 static int mock_id(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd)
 {
-	struct platform_device *pdev = to_platform_device(cxlds->dev);
 	struct cxl_mbox_identify id = {
 		.fw_revision = { "mock fw v1 " },
 		.lsa_size = cpu_to_le32(LSA_SIZE),
-		/* FIXME: Add partition support */
-		.partition_align = cpu_to_le64(0),
+		.partition_align =
+			cpu_to_le64(SZ_256M / CXL_CAPACITY_MULTIPLIER),
+		.total_capacity =
+			cpu_to_le64(DEV_SIZE / CXL_CAPACITY_MULTIPLIER),
 	};
-	u64 capacity = 0;
-	int i;
 
 	if (cmd->size_out < sizeof(id))
 		return -EINVAL;
 
-	for (i = 0; i < 2; i++) {
-		struct resource *res;
-
-		res = platform_get_resource(pdev, IORESOURCE_MEM, i);
-		if (!res)
-			break;
-
-		capacity += resource_size(res) / CXL_CAPACITY_MULTIPLIER;
+	memcpy(cmd->payload_out, &id, sizeof(id));
 
-		if (le64_to_cpu(id.partition_align))
-			continue;
+	return 0;
+}
 
-		if (res->desc == IORES_DESC_PERSISTENT_MEMORY)
-			id.persistent_capacity = cpu_to_le64(
-				resource_size(res) / CXL_CAPACITY_MULTIPLIER);
-		else
-			id.volatile_capacity = cpu_to_le64(
-				resource_size(res) / CXL_CAPACITY_MULTIPLIER);
-	}
+static int mock_partition_info(struct cxl_dev_state *cxlds,
+			       struct cxl_mbox_cmd *cmd)
+{
+	struct cxl_mbox_get_partition_info pi = {
+		.active_volatile_cap =
+			cpu_to_le64(DEV_SIZE / 2 / CXL_CAPACITY_MULTIPLIER),
+		.active_persistent_cap =
+			cpu_to_le64(DEV_SIZE / 2 / CXL_CAPACITY_MULTIPLIER),
+	};
 
-	id.total_capacity = cpu_to_le64(capacity);
+	if (cmd->size_out < sizeof(pi))
+		return -EINVAL;
 
-	memcpy(cmd->payload_out, &id, sizeof(id));
+	memcpy(cmd->payload_out, &pi, sizeof(pi));
 
 	return 0;
 }
@@ -221,6 +221,9 @@ static int cxl_mock_mbox_send(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *
 	case CXL_MBOX_OP_GET_LSA:
 		rc = mock_get_lsa(cxlds, cmd);
 		break;
+	case CXL_MBOX_OP_GET_PARTITION_INFO:
+		rc = mock_partition_info(cxlds, cmd);
+		break;
 	case CXL_MBOX_OP_SET_LSA:
 		rc = mock_set_lsa(cxlds, cmd);
 		break;