@@ -34,6 +34,42 @@ struct iort_its_msi_chip {
u32 translation_id;
};
+static int iort_dev_match(struct device *dev, void *data)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ const char *name = data;
+
+ return !strcmp(pdev->name, name);
+}
+
+/**
+ * iort_find_iommu_device- Retrieve IOMMU platform_device associated with
+ * IORT node
+ *
+ * @node: IORT table node associated with the device
+ *
+ * Returns: device on success
+ * NULL on failure
+ */
+struct platform_device *iort_find_iommu_device(struct acpi_iort_node *node)
+{
+ struct acpi_iort_node *curr;
+ struct device *dev = NULL;
+ const struct iort_iommu_config *cfg = iort_get_iommu_config(node);
+
+ if (!cfg)
+ return NULL;
+
+ while ((dev = bus_find_device(&platform_bus_type, dev,
+ (void *)cfg->name, iort_dev_match))) {
+ curr = *(struct acpi_iort_node **) dev_get_platdata(dev);
+ if (curr == node)
+ return to_platform_device(dev);
+ }
+
+ return NULL;
+}
+
struct iort_ops_node {
struct list_head list;
struct acpi_iort_node *node;
@@ -32,6 +32,7 @@ u32 iort_pci_get_msi_rid(struct pci_dev *pdev, u32 req_id);
struct irq_domain *iort_pci_get_domain(struct pci_dev *pdev, u32 req_id);
/* IOMMU interface */
+struct platform_device *iort_find_iommu_device(struct acpi_iort_node *node);
const struct iommu_ops *iort_iommu_configure(struct device *dev);
#else
static inline bool iort_node_match(u8 type) { return false; }
@@ -41,6 +42,8 @@ static inline struct irq_domain *
iort_pci_get_domain(struct pci_dev *pdev, u32 req_id) { return NULL; }
/* IOMMU interface */
+static inline struct platform_device *
+iort_find_iommu_device(struct acpi_iort_node *node) { return NULL; }
static inline const struct iommu_ops *
iort_iommu_configure(struct device *dev) { return NULL; }
#endif
Some kernel components (ie ARM SMMU drivers) require to look-up the platform device corresponding to a specific IORT node to carry out streamid translation. Platform devices created for ARM SMMU components out of IORT tables have no fwnode token initialized, in that they do not have any device tree node or ACPI device backing them. Therefore, to implement the IORT node<->platform device look-up, this patch adds a function to the IORT kernel layer that allows to retrieve the platform device corresponding to an IORT node through platform device name and its platform_data (that for platform devices created out of IORT nodes for SMMUs contains a pointer to the respective IORT node). Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Hanjun Guo <hanjun.guo@linaro.org> Cc: Tomasz Nowicki <tn@semihalf.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> --- drivers/acpi/iort.c | 36 ++++++++++++++++++++++++++++++++++++ include/linux/iort.h | 3 +++ 2 files changed, 39 insertions(+)