ACPI/IORT: Add an input ID to acpi_dma_configure()

Some HW devices are created as child devices of proprietary busses,
that have a bus specific policy defining how the child devices
wires representing the devices ID are translated into IOMMU and
IRQ controllers device IDs.

Current IORT code provides translations for:

- PCI devices, where the device ID is well identified at bus level
  as the requester ID (RID)
- Platform devices that are endpoint devices where the device ID is
  retrieved from the ACPI object IORT mappings (Named components single
  mappings). A platform device is represented in IORT as a named
  component node

For devices that are child devices of proprietary busses the IORT
firmware represents the bus node as a named component node in IORT
and it is up to that named component node to define in/out bus
specific ID translations for the bus child devices that are
allocated and created in a bus specific manner.

In order to make IORT ID translations available for proprietary
bus child devices, the current ACPI (and IORT) code must be
augmented to provide an additional ID parameter to acpi_dma_configure()
representing the child devices input ID. This ID is bus specific
and it is retrieved in bus specific code.

By adding an ID parameter to acpi_dma_configure(), the IORT
code can map the child device ID to an IOMMU stream ID through
the IORT named component representing the bus in/out ID mappings.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Link: https://lore.kernel.org/r/20200619082013.13661-6-lorenzo.pieralisi@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

2 files changed, 49 insertions, 18 deletions

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index 421c6976ab81..ec782e4a0fe4 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -978,19 +978,54 @@ static void iort_named_component_init(struct device *dev,
 					   nc->node_flags);
 }
 
+static int iort_nc_iommu_map(struct device *dev, struct acpi_iort_node *node)
+{
+	struct acpi_iort_node *parent;
+	int err = -ENODEV, i = 0;
+	u32 streamid = 0;
+
+	do {
+
+		parent = iort_node_map_platform_id(node, &streamid,
+						   IORT_IOMMU_TYPE,
+						   i++);
+
+		if (parent)
+			err = iort_iommu_xlate(dev, parent, streamid);
+	} while (parent && !err);
+
+	return err;
+}
+
+static int iort_nc_iommu_map_id(struct device *dev,
+				struct acpi_iort_node *node,
+				const u32 *in_id)
+{
+	struct acpi_iort_node *parent;
+	u32 streamid;
+
+	parent = iort_node_map_id(node, *in_id, &streamid, IORT_IOMMU_TYPE);
+	if (parent)
+		return iort_iommu_xlate(dev, parent, streamid);
+
+	return -ENODEV;
+}
+
+
 /**
- * iort_iommu_configure - Set-up IOMMU configuration for a device.
+ * iort_iommu_configure_id - Set-up IOMMU configuration for a device.
  *
  * @dev: device to configure
+ * @id_in: optional input id const value pointer
  *
  * Returns: iommu_ops pointer on configuration success
  *          NULL on configuration failure
  */
-const struct iommu_ops *iort_iommu_configure(struct device *dev)
+const struct iommu_ops *iort_iommu_configure_id(struct device *dev,
+						const u32 *id_in)
 {
-	struct acpi_iort_node *node, *parent;
+	struct acpi_iort_node *node;
 	const struct iommu_ops *ops;
-	u32 streamid = 0;
 	int err = -ENODEV;
 
 	/*
@@ -1019,21 +1054,13 @@ const struct iommu_ops *iort_iommu_configure(struct device *dev)
 		if (fwspec && iort_pci_rc_supports_ats(node))
 			fwspec->flags |= IOMMU_FWSPEC_PCI_RC_ATS;
 	} else {
-		int i = 0;
-
 		node = iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT,
 				      iort_match_node_callback, dev);
 		if (!node)
 			return NULL;
 
-		do {
-			parent = iort_node_map_platform_id(node, &streamid,
-							   IORT_IOMMU_TYPE,
-							   i++);
-
-			if (parent)
-				err = iort_iommu_xlate(dev, parent, streamid);
-		} while (parent && !err);
+		err = id_in ? iort_nc_iommu_map_id(dev, node, id_in) :
+			      iort_nc_iommu_map(dev, node);
 
 		if (!err)
 			iort_named_component_init(dev, node);
@@ -1058,6 +1085,7 @@ const struct iommu_ops *iort_iommu_configure(struct device *dev)
 
 	return ops;
 }
+
 #else
 static inline const struct iommu_ops *iort_fwspec_iommu_ops(struct device *dev)
 { return NULL; }
@@ -1066,7 +1094,8 @@ static inline int iort_add_device_replay(const struct iommu_ops *ops,
 { return 0; }
 int iort_iommu_msi_get_resv_regions(struct device *dev, struct list_head *head)
 { return 0; }
-const struct iommu_ops *iort_iommu_configure(struct device *dev)
+const struct iommu_ops *iort_iommu_configure_id(struct device *dev,
+						const u32 *input_id)
 { return NULL; }
 #endif
 
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 8777faced51a..2142f1554761 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1457,8 +1457,10 @@ int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset,
  * acpi_dma_configure - Set-up DMA configuration for the device.
  * @dev: The pointer to the device
  * @attr: device dma attributes
+ * @input_id: input device id const value pointer
  */
-int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
+int acpi_dma_configure_id(struct device *dev, enum dev_dma_attr attr,
+			  const u32 *input_id)
 {
 	const struct iommu_ops *iommu;
 	u64 dma_addr = 0, size = 0;
@@ -1470,7 +1472,7 @@ int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
 
 	iort_dma_setup(dev, &dma_addr, &size);
 
-	iommu = iort_iommu_configure(dev);
+	iommu = iort_iommu_configure_id(dev, input_id);
 	if (PTR_ERR(iommu) == -EPROBE_DEFER)
 		return -EPROBE_DEFER;
 
@@ -1479,7 +1481,7 @@ int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
 
 	return 0;
 }
-EXPORT_SYMBOL_GPL(acpi_dma_configure);
+EXPORT_SYMBOL_GPL(acpi_dma_configure_id);
 
 static void acpi_init_coherency(struct acpi_device *adev)
 {