[PATCH v6 16/16] drivers: acpi: iort: introduce iort_iommu_configure

[Lorenzo Pieralisi]

DT based systems have a generic kernel API to configure IOMMUs
for devices (ie of_iommu_configure()).

On ARM based ACPI systems, the of_iommu_configure() equivalent can
be implemented atop ACPI IORT kernel API, with the corresponding
functions to map device identifiers to IOMMUs and retrieve the
corresponding IOMMU operations necessary for DMA operations set-up.

By relying on the iommu_fwspec generic kernel infrastructure,
implement the IORT based IOMMU configuration for ARM ACPI systems
and hook it up in the ACPI kernel layer that implements DMA
configuration for a device.

Signed-off-by: Lorenzo Pieralisi 
Cc: Hanjun Guo 
Cc: Tomasz Nowicki 
Cc: "Rafael J. Wysocki" 
---
 drivers/acpi/arm64/iort.c | 99 +++
 drivers/acpi/scan.c   |  7 +++-
 include/linux/acpi_iort.h |  6 +++
 3 files changed, 111 insertions(+), 1 deletion(-)

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index db7b153..5741bfd 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -28,6 +28,8 @@
 
 #define IORT_TYPE_MASK(type)   (1 << (type))
 #define IORT_MSI_TYPE  (1 << ACPI_IORT_NODE_ITS_GROUP)
+#define IORT_IOMMU_TYPE((1 << ACPI_IORT_NODE_SMMU) |   \
+   (1 << ACPI_IORT_NODE_SMMU_V3))
 
 struct iort_its_msi_chip {
struct list_headlist;
@@ -501,6 +503,103 @@ struct irq_domain *iort_get_device_domain(struct device 
*dev, u32 req_id)
return irq_find_matching_fwnode(handle, DOMAIN_BUS_PCI_MSI);
 }
 
+static int __get_pci_rid(struct pci_dev *pdev, u16 alias, void *data)
+{
+   u32 *rid = data;
+
+   *rid = alias;
+   return 0;
+}
+
+static int arm_smmu_iort_xlate(struct device *dev, u32 streamid,
+  struct fwnode_handle *fwnode,
+  const struct iommu_ops *ops)
+{
+   int ret = iommu_fwspec_init(dev, fwnode, ops);
+
+   if (!ret)
+   ret = iommu_fwspec_add_ids(dev, , 1);
+
+   return ret;
+}
+
+static const struct iommu_ops *iort_iommu_xlate(struct device *dev,
+   struct acpi_iort_node *node,
+   u32 streamid)
+{
+   struct fwnode_handle *iort_fwnode = NULL;
+   const struct iommu_ops *ops = NULL;
+   int ret = -ENODEV;
+
+   if (node) {
+   iort_fwnode = iort_get_fwnode(node);
+   if (!iort_fwnode)
+   return NULL;
+
+   ops = fwnode_iommu_get_ops(iort_fwnode);
+   if (!ops)
+   return NULL;
+
+   ret = arm_smmu_iort_xlate(dev, streamid,
+ iort_fwnode, ops);
+   }
+
+   return ret ? NULL : ops;
+}
+
+/**
+ * iort_iommu_configure - Set-up IOMMU configuration for a device.
+ *
+ * @dev: device to configure
+ *
+ * Returns: iommu_ops pointer on configuration success
+ *  NULL on configuration failure
+ */
+const struct iommu_ops *iort_iommu_configure(struct device *dev)
+{
+   struct acpi_iort_node *node, *parent;
+   const struct iommu_ops *ops = NULL;
+   u32 streamid = 0;
+
+   if (dev_is_pci(dev)) {
+   struct pci_bus *bus = to_pci_dev(dev)->bus;
+   u32 rid;
+
+   pci_for_each_dma_alias(to_pci_dev(dev), __get_pci_rid,
+  );
+
+   node = iort_scan_node(ACPI_IORT_NODE_PCI_ROOT_COMPLEX,
+ iort_match_node_callback, >dev);
+   if (!node)
+   return NULL;
+
+   parent = iort_node_map_rid(node, rid, ,
+  IORT_IOMMU_TYPE);
+
+   ops = iort_iommu_xlate(dev, parent, streamid);
+
+   } else {
+   int i = 0;
+
+   node = iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT,
+ iort_match_node_callback, dev);
+   if (!node)
+   return NULL;
+
+   parent = iort_node_get_id(node, ,
+ IORT_IOMMU_TYPE, i++);
+
+   while (parent) {
+   ops = iort_iommu_xlate(dev, parent, streamid);
+
+   parent = iort_node_get_id(node, ,
+ IORT_IOMMU_TYPE, i++);
+   }
+   }
+
+   return ops;
+}
+
 static void __init acpi_iort_register_irq(int hwirq, const char *name,
  int trigger,
  struct resource *res)
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 694e0b6..e5f7004 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -7,6 +7,7 @@
 #include 
 #include 
 #include 
+#include 
 #include 
 #include 
 #include 

[PATCH v6 16/16] drivers: acpi: iort: introduce iort_iommu_configure

[Lorenzo Pieralisi]

DT based systems have a generic kernel API to configure IOMMUs
for devices (ie of_iommu_configure()).

On ARM based ACPI systems, the of_iommu_configure() equivalent can
be implemented atop ACPI IORT kernel API, with the corresponding
functions to map device identifiers to IOMMUs and retrieve the
corresponding IOMMU operations necessary for DMA operations set-up.

By relying on the iommu_fwspec generic kernel infrastructure,
implement the IORT based IOMMU configuration for ARM ACPI systems
and hook it up in the ACPI kernel layer that implements DMA
configuration for a device.

Signed-off-by: Lorenzo Pieralisi 
Cc: Hanjun Guo 
Cc: Tomasz Nowicki 
Cc: "Rafael J. Wysocki" 
---
 drivers/acpi/arm64/iort.c | 99 +++
 drivers/acpi/scan.c   |  7 +++-
 include/linux/acpi_iort.h |  6 +++
 3 files changed, 111 insertions(+), 1 deletion(-)

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index db7b153..5741bfd 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -28,6 +28,8 @@
 
 #define IORT_TYPE_MASK(type)   (1 << (type))
 #define IORT_MSI_TYPE  (1 << ACPI_IORT_NODE_ITS_GROUP)
+#define IORT_IOMMU_TYPE((1 << ACPI_IORT_NODE_SMMU) |   \
+   (1 << ACPI_IORT_NODE_SMMU_V3))
 
 struct iort_its_msi_chip {
struct list_headlist;
@@ -501,6 +503,103 @@ struct irq_domain *iort_get_device_domain(struct device 
*dev, u32 req_id)
return irq_find_matching_fwnode(handle, DOMAIN_BUS_PCI_MSI);
 }
 
+static int __get_pci_rid(struct pci_dev *pdev, u16 alias, void *data)
+{
+   u32 *rid = data;
+
+   *rid = alias;
+   return 0;
+}
+
+static int arm_smmu_iort_xlate(struct device *dev, u32 streamid,
+  struct fwnode_handle *fwnode,
+  const struct iommu_ops *ops)
+{
+   int ret = iommu_fwspec_init(dev, fwnode, ops);
+
+   if (!ret)
+   ret = iommu_fwspec_add_ids(dev, , 1);
+
+   return ret;
+}
+
+static const struct iommu_ops *iort_iommu_xlate(struct device *dev,
+   struct acpi_iort_node *node,
+   u32 streamid)
+{
+   struct fwnode_handle *iort_fwnode = NULL;
+   const struct iommu_ops *ops = NULL;
+   int ret = -ENODEV;
+
+   if (node) {
+   iort_fwnode = iort_get_fwnode(node);
+   if (!iort_fwnode)
+   return NULL;
+
+   ops = fwnode_iommu_get_ops(iort_fwnode);
+   if (!ops)
+   return NULL;
+
+   ret = arm_smmu_iort_xlate(dev, streamid,
+ iort_fwnode, ops);
+   }
+
+   return ret ? NULL : ops;
+}
+
+/**
+ * iort_iommu_configure - Set-up IOMMU configuration for a device.
+ *
+ * @dev: device to configure
+ *
+ * Returns: iommu_ops pointer on configuration success
+ *  NULL on configuration failure
+ */
+const struct iommu_ops *iort_iommu_configure(struct device *dev)
+{
+   struct acpi_iort_node *node, *parent;
+   const struct iommu_ops *ops = NULL;
+   u32 streamid = 0;
+
+   if (dev_is_pci(dev)) {
+   struct pci_bus *bus = to_pci_dev(dev)->bus;
+   u32 rid;
+
+   pci_for_each_dma_alias(to_pci_dev(dev), __get_pci_rid,
+  );
+
+   node = iort_scan_node(ACPI_IORT_NODE_PCI_ROOT_COMPLEX,
+ iort_match_node_callback, >dev);
+   if (!node)
+   return NULL;
+
+   parent = iort_node_map_rid(node, rid, ,
+  IORT_IOMMU_TYPE);
+
+   ops = iort_iommu_xlate(dev, parent, streamid);
+
+   } else {
+   int i = 0;
+
+   node = iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT,
+ iort_match_node_callback, dev);
+   if (!node)
+   return NULL;
+
+   parent = iort_node_get_id(node, ,
+ IORT_IOMMU_TYPE, i++);
+
+   while (parent) {
+   ops = iort_iommu_xlate(dev, parent, streamid);
+
+   parent = iort_node_get_id(node, ,
+ IORT_IOMMU_TYPE, i++);
+   }
+   }
+
+   return ops;
+}
+
 static void __init acpi_iort_register_irq(int hwirq, const char *name,
  int trigger,
  struct resource *res)
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 694e0b6..e5f7004 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -7,6 +7,7 @@
 #include 
 #include 
 #include 
+#include 
 #include 
 #include 
 #include 
@@ -1377,6 +1378,8 @@ enum dev_dma_attr acpi_get_dma_attr(struct acpi_device 
*adev)