[RFC PATCH v2 4/4] ACPI: IORT: SMMUv3 nodes MSI support

[Hanjun Guo]

From: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>

Since we make single mappings valid for SMMUv3 (and PMCG), also
we have a mapping index for SMMUv3 MSI, we can directly use that
index to get the map entry, then retrieve dev ID and ITS parent
to add SMMUv3 MSI support.

Introduce a new API iort_set_device_domain() to find the MSI domain
for an SMMUv3 (or any other IORT table node) to reduce the complex
of doing that via acpi_configure_pmsi_domain(), then reuse the
iort_node_get_id() to get the dev id for SMMU MSI.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>
Signed-off-by: Hanjun Guo <hanjun.guo at linaro.org>
---
 drivers/acpi/arm64/iort.c | 99 ++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 81 insertions(+), 18 deletions(-)

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index 269959e..bbab2ab 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -357,7 +357,8 @@ struct acpi_iort_node *iort_node_get_id(struct acpi_iort_node *node,
 
 	if (map->flags & ACPI_IORT_ID_SINGLE_MAPPING) {
 		if (node->type == ACPI_IORT_NODE_NAMED_COMPONENT ||
-		    node->type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX) {
+		    node->type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX ||
+		    node->type == ACPI_IORT_NODE_SMMU_V3) {
 			*id_out = map->output_base;
 			return parent;
 		}
@@ -366,8 +367,8 @@ struct acpi_iort_node *iort_node_get_id(struct acpi_iort_node *node,
 	return NULL;
 }
 
-static int iort_get_smmu_v3_id_mapping_index(struct acpi_iort_node *node,
-					     u32 *index)
+static int iort_get_id_mapping_index(struct acpi_iort_node *node,
+				     u32 *index)
 {
 	struct acpi_iort_smmu_v3 *smmu;
 
@@ -378,20 +379,28 @@ static int iort_get_smmu_v3_id_mapping_index(struct acpi_iort_node *node,
 	if (node->revision < 1)
 		return -EINVAL;
 
-	smmu = (struct acpi_iort_smmu_v3 *)node->node_data;
-	/* if any of the gsi for control interrupts is not 0, ignore the MSI */
-	if (smmu->event_gsiv || smmu->pri_gsiv || smmu->gerr_gsiv
-	    || smmu->sync_gsiv)
-		return -EINVAL;
+	switch (node->type) {
+	case ACPI_IORT_NODE_SMMU_V3:
+		smmu = (struct acpi_iort_smmu_v3 *)node->node_data;
+		/*
+		 * if any of the gsi for control interrupts is not 0,
+		 * ignore the MSI
+		 */
+		if (smmu->event_gsiv || smmu->pri_gsiv || smmu->gerr_gsiv
+		    || smmu->sync_gsiv)
+			return -EINVAL;
 
-	if (smmu->id_mapping_index >= node->mapping_count) {
-		pr_err(FW_BUG "[node %p type %d] ID mapping index overflows valid mappings\n",
-		       node, node->type);
+		if (smmu->id_mapping_index >= node->mapping_count) {
+			pr_err(FW_BUG "[node %p type %d] ID mapping index overflows valid mappings\n",
+			       node, node->type);
+			return -EINVAL;
+		}
+
+		*index = smmu->id_mapping_index;
+		return 0;
+	default:
 		return -EINVAL;
 	}
-
-	*index = smmu->id_mapping_index;
-	return 0;
 }
 
 static struct acpi_iort_node *iort_node_map_id(struct acpi_iort_node *node,
@@ -431,7 +440,7 @@ static struct acpi_iort_node *iort_node_map_id(struct acpi_iort_node *node,
 		 *  associated ID map for single mapping cases.
 		 */
 		if (node->type == ACPI_IORT_NODE_SMMU_V3)
-			ret = iort_get_smmu_v3_id_mapping_index(node, &index);
+			ret = iort_get_id_mapping_index(node, &index);
 
 		/* Do the ID translation */
 		for (i = 0; i < node->mapping_count; i++, map++) {
@@ -555,9 +564,18 @@ int iort_pmsi_get_dev_id(struct device *dev, u32 *dev_id)
 	if (!node)
 		return -ENODEV;
 
-	for (i = 0; i < node->mapping_count; i++) {
-		if (iort_node_map_platform_id(node, dev_id, IORT_MSI_TYPE, i))
-			return 0;
+	if (node->type == ACPI_IORT_NODE_SMMU_V3) {
+		u32 index;
+
+		if (!iort_get_id_mapping_index(node, &index)) {
+			if (iort_node_get_id(node, dev_id, index))
+				return 0;
+		}
+	} else {
+		for (i = 0; i < node->mapping_count; i++) {
+			if (iort_node_map_platform_id(node, dev_id, IORT_MSI_TYPE, i))
+				return 0;
+		}
 	}
 
 	return -ENODEV;
@@ -620,6 +638,49 @@ struct irq_domain *iort_get_device_domain(struct device *dev, u32 req_id)
 	return irq_find_matching_fwnode(handle, DOMAIN_BUS_PCI_MSI);
 }
 
+static void iort_set_device_domain(struct device *dev,
+				   struct acpi_iort_node *node)
+{
+	struct acpi_iort_its_group *its;
+	struct acpi_iort_node *msi_parent;
+	struct acpi_iort_id_mapping *map;
+	struct fwnode_handle *iort_fwnode;
+	struct irq_domain *domain;
+	int ret, index;
+
+	ret = iort_get_id_mapping_index(node, &index);
+	if (ret < 0)
+		return;
+
+	map = ACPI_ADD_PTR(struct acpi_iort_id_mapping, node,
+			   node->mapping_offset + index * sizeof(*map));
+
+	/* Firmware bug! */
+	if (!map->output_reference ||
+	    !(map->flags & ACPI_IORT_ID_SINGLE_MAPPING)) {
+		pr_err(FW_BUG "[node %p type %d] Invalid MSI mapping\n",
+		       node, node->type);
+		return;
+	}
+
+	msi_parent = ACPI_ADD_PTR(struct acpi_iort_node, iort_table,
+				  map->output_reference);
+
+	if (!msi_parent || msi_parent->type != ACPI_IORT_NODE_ITS_GROUP)
+		return;
+
+	/* Move to ITS specific data */
+	its = (struct acpi_iort_its_group *)msi_parent->node_data;
+
+	iort_fwnode = iort_find_domain_token(its->identifiers[0]);
+	if (!iort_fwnode)
+		return;
+
+	domain = irq_find_matching_fwnode(iort_fwnode, DOMAIN_BUS_PLATFORM_MSI);
+	if (domain)
+		dev_set_msi_domain(dev, domain);
+}
+
 /**
  * iort_get_platform_device_domain() - Find MSI domain related to a
  * platform device
@@ -1246,6 +1307,8 @@ static int __init iort_add_smmu_platform_device(struct acpi_iort_node *node)
 	/* Configure DMA for the page table walker */
 	acpi_dma_configure(&pdev->dev, attr);
 
+	iort_set_device_domain(&pdev->dev, node);
+
 	ret = platform_device_add(pdev);
 	if (ret)
 		goto dma_deconfigure;
-- 
1.7.12.4