iommu/arm-smmu: Add IORT configuration

In ACPI based systems, in order to be able to create platform
devices and initialize them for ARM SMMU components, the IORT
kernel implementation requires a set of static functions to be
used by the IORT kernel layer to configure platform devices for
ARM SMMU components.

Add static configuration functions to the IORT kernel layer for
the ARM SMMU components, so that the ARM SMMU driver can
initialize its respective platform device by relying on the IORT
kernel infrastructure and by adding a corresponding ACPI device
early probe section entry.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Tomasz Nowicki <tn@semihalf.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Tomasz Nowicki <tn@semihalf.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>

1 files changed, 76 insertions, 1 deletions

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index e068c6f4d1d6..41b67ce999bf 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -28,6 +28,8 @@
 
 #define pr_fmt(fmt) "arm-smmu: " fmt
 
+#include <linux/acpi.h>
+#include <linux/acpi_iort.h>
 #include <linux/atomic.h>
 #include <linux/delay.h>
 #include <linux/dma-iommu.h>
@@ -1911,6 +1913,64 @@ 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)
+{
+	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;
+	case ACPI_IORT_SMMU_V2:
+		smmu->version = ARM_SMMU_V2;
+		smmu->model = GENERIC_SMMU;
+		break;
+	case ACPI_IORT_SMMU_CORELINK_MMU500:
+		smmu->version = ARM_SMMU_V2;
+		smmu->model = ARM_MMU500;
+		break;
+	default:
+		ret = -ENODEV;
+	}
+
+	return ret;
+}
+
+static int arm_smmu_device_acpi_probe(struct platform_device *pdev,
+				      struct arm_smmu_device *smmu)
+{
+	struct device *dev = smmu->dev;
+	struct acpi_iort_node *node =
+		*(struct acpi_iort_node **)dev_get_platdata(dev);
+	struct acpi_iort_smmu *iort_smmu;
+	int ret;
+
+	/* 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;
+
+	/* Ignore the configuration access interrupt */
+	smmu->num_global_irqs = 1;
+
+	if (iort_smmu->flags & ACPI_IORT_SMMU_COHERENT_WALK)
+		smmu->features |= ARM_SMMU_FEAT_COHERENT_WALK;
+
+	return 0;
+}
+#else
+static inline int arm_smmu_device_acpi_probe(struct platform_device *pdev,
+					     struct arm_smmu_device *smmu)
+{
+	return -ENODEV;
+}
+#endif
+
 static int arm_smmu_device_dt_probe(struct platform_device *pdev,
 				    struct arm_smmu_device *smmu)
 {
@@ -1962,7 +2022,11 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
 	}
 	smmu->dev = dev;
 
-	err = arm_smmu_device_dt_probe(pdev, smmu);
+	if (dev->of_node)
+		err = arm_smmu_device_dt_probe(pdev, smmu);
+	else
+		err = arm_smmu_device_acpi_probe(pdev, smmu);
+
 	if (err)
 		return err;
 
@@ -2110,6 +2174,17 @@ IOMMU_OF_DECLARE(arm_mmu401, "arm,mmu-401", arm_smmu_of_init);
 IOMMU_OF_DECLARE(arm_mmu500, "arm,mmu-500", arm_smmu_of_init);
 IOMMU_OF_DECLARE(cavium_smmuv2, "cavium,smmu-v2", arm_smmu_of_init);
 
+#ifdef CONFIG_ACPI
+static int __init arm_smmu_acpi_init(struct acpi_table_header *table)
+{
+	if (iort_node_match(ACPI_IORT_NODE_SMMU))
+		return arm_smmu_init();
+
+	return 0;
+}
+IORT_ACPI_DECLARE(arm_smmu, ACPI_SIG_IORT, arm_smmu_acpi_init);
+#endif
+
 MODULE_DESCRIPTION("IOMMU API for ARM architected SMMU implementations");
 MODULE_AUTHOR("Will Deacon <will.deacon@arm.com>");
 MODULE_LICENSE("GPL v2");