[PATCH] iommu/arm-smmu: Report smmu type in dmesg

[Robert Richter]

The ARM SMMU detection especially depends from system firmware. For
better diagnostic, log the detected type in dmesg.

The smmu type's name is now stored in struct arm_smmu_type and ACPI
code is modified to use that struct too. Rename ARM_SMMU_MATCH_DATA()
macro to ARM_SMMU_TYPE() for better readability.

Signed-off-by: Robert Richter <rrichter@xxxxxxxxxx>
---
 drivers/iommu/arm-smmu.c | 61 ++++++++++++++++++++++++------------------------
 1 file changed, 30 insertions(+), 31 deletions(-)

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index abf6496843a6..5c793b3d3173 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -366,6 +366,7 @@ struct arm_smmu_device {
 	u32				options;
 	enum arm_smmu_arch_version	version;
 	enum arm_smmu_implementation	model;
+	const char			*name;
 
 	u32				num_context_banks;
 	u32				num_s2_context_banks;
@@ -1955,19 +1956,20 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu)
 	return 0;
 }
 
-struct arm_smmu_match_data {
+struct arm_smmu_type {
 	enum arm_smmu_arch_version version;
 	enum arm_smmu_implementation model;
+	const char *name;
 };
 
-#define ARM_SMMU_MATCH_DATA(name, ver, imp)	\
-static struct arm_smmu_match_data name = { .version = ver, .model = imp }
+#define ARM_SMMU_TYPE(var, ver, imp, _name)	\
+static struct arm_smmu_type var = { .version = ver, .model = imp, .name = _name }
 
-ARM_SMMU_MATCH_DATA(smmu_generic_v1, ARM_SMMU_V1, GENERIC_SMMU);
-ARM_SMMU_MATCH_DATA(smmu_generic_v2, ARM_SMMU_V2, GENERIC_SMMU);
-ARM_SMMU_MATCH_DATA(arm_mmu401, ARM_SMMU_V1_64K, GENERIC_SMMU);
-ARM_SMMU_MATCH_DATA(arm_mmu500, ARM_SMMU_V2, ARM_MMU500);
-ARM_SMMU_MATCH_DATA(cavium_smmuv2, ARM_SMMU_V2, CAVIUM_SMMUV2);
+ARM_SMMU_TYPE(smmu_generic_v1, ARM_SMMU_V1, GENERIC_SMMU, "smmu-generic-v1");
+ARM_SMMU_TYPE(smmu_generic_v2, ARM_SMMU_V2, GENERIC_SMMU, "smmu-generic-v2");
+ARM_SMMU_TYPE(arm_mmu401, ARM_SMMU_V1_64K, GENERIC_SMMU, "arm-mmu401");
+ARM_SMMU_TYPE(arm_mmu500, ARM_SMMU_V2, ARM_MMU500, "arm-mmu500");
+ARM_SMMU_TYPE(cavium_smmuv2, ARM_SMMU_V2, CAVIUM_SMMUV2, "cavium-smmuv2");
 
 static const struct of_device_id arm_smmu_of_match[] = {
 	{ .compatible = "arm,smmu-v1", .data = &smmu_generic_v1 },
@@ -1981,29 +1983,19 @@ static const struct of_device_id arm_smmu_of_match[] = {
 MODULE_DEVICE_TABLE(of, arm_smmu_of_match);
 
 #ifdef CONFIG_ACPI
-static int acpi_smmu_get_data(u32 model, struct arm_smmu_device *smmu)
+static struct arm_smmu_type *acpi_smmu_get_type(u32 model)
 {
-	int ret = 0;
-
 	switch (model) {
 	case ACPI_IORT_SMMU_V1:
 	case ACPI_IORT_SMMU_CORELINK_MMU400:
-		smmu->version = ARM_SMMU_V1;
-		smmu->model = GENERIC_SMMU;
-		break;
+		return &smmu_generic_v1;
 	case ACPI_IORT_SMMU_V2:
-		smmu->version = ARM_SMMU_V2;
-		smmu->model = GENERIC_SMMU;
-		break;
+		return &smmu_generic_v2;
 	case ACPI_IORT_SMMU_CORELINK_MMU500:
-		smmu->version = ARM_SMMU_V2;
-		smmu->model = ARM_MMU500;
-		break;
-	default:
-		ret = -ENODEV;
+		return &arm_mmu500;
 	}
 
-	return ret;
+	return NULL;
 }
 
 static int arm_smmu_device_acpi_probe(struct platform_device *pdev,
@@ -2013,14 +2005,18 @@ static int arm_smmu_device_acpi_probe(struct platform_device *pdev,
 	struct acpi_iort_node *node =
 		*(struct acpi_iort_node **)dev_get_platdata(dev);
 	struct acpi_iort_smmu *iort_smmu;
-	int ret;
+	struct arm_smmu_type *type;
 
 	/* Retrieve SMMU1/2 specific data */
 	iort_smmu = (struct acpi_iort_smmu *)node->node_data;
 
-	ret = acpi_smmu_get_data(iort_smmu->model, smmu);
-	if (ret < 0)
-		return ret;
+	type = acpi_smmu_get_type(iort_smmu->model);
+	if (!type)
+		return -ENODEV;
+
+	smmu->version	= type->version;
+	smmu->model	= type->model;
+	smmu->name	= type->name;
 
 	/* Ignore the configuration access interrupt */
 	smmu->num_global_irqs = 1;
@@ -2041,8 +2037,8 @@ static inline int arm_smmu_device_acpi_probe(struct platform_device *pdev,
 static int arm_smmu_device_dt_probe(struct platform_device *pdev,
 				    struct arm_smmu_device *smmu)
 {
-	const struct arm_smmu_match_data *data;
 	struct device *dev = &pdev->dev;
+	const struct arm_smmu_type *type;
 	bool legacy_binding;
 
 	if (of_property_read_u32(dev->of_node, "#global-interrupts",
@@ -2051,9 +2047,10 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev,
 		return -ENODEV;
 	}
 
-	data = of_device_get_match_data(dev);
-	smmu->version = data->version;
-	smmu->model = data->model;
+	type = of_device_get_match_data(dev);
+	smmu->version	= type->version;
+	smmu->model	= type->model;
+	smmu->name	= type->name;
 
 	parse_driver_options(smmu);
 
@@ -2098,6 +2095,8 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
 	if (err)
 		return err;
 
+	dev_notice(dev, "%s detected", smmu->name);
+
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	ioaddr = res->start;
 	smmu->base = devm_ioremap_resource(dev, res);
-- 
2.11.0