From: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Date: Fri, 13 Oct 2017 15:09:50 +0800
Subject: ACPI/IORT: Enable SMMUv3/PMCG IORT MSI domain set-up

Git-commit: 65637901a3409f8a7952750e975536bde70fa1f8
Patch-mainline: v4.15-rc1
References: bsc#1084475

ITS specific mappings for SMMUv3/PMCG components can be retrieved
through special index mapping entries introduced in IORT revision C.

Introduce a new API iort_set_device_domain() to set the MSI domain for
SMMUv3/PMCG nodes (extendable to any future IORT node requiring special
index ITS mapping entries) that represent MSI through special index
mappings in order to enable MSI support for the devices their nodes
represent.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>
---
 drivers/acpi/arm64/iort.c | 45 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 45 insertions(+)

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index 3d7e3cd2eae8..7dc964f4d8f1 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -638,6 +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 index;
+
+	index = iort_get_id_mapping_index(node);
+	if (index < 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
@@ -1261,6 +1304,8 @@ static int __init iort_add_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;
-- 
2.11.0