Add of_pci_dma_configure() to allow updating the dma configuration of the pci device using the configuration from DT of the parent of the root bridge device.
Signed-off-by: Murali Karicheri <m-kariche...@ti.com> --- drivers/of/of_pci.c | 39 +++++++++++++++++++++++++++++++++++++++ include/linux/of_pci.h | 12 ++++++++++++ 2 files changed, 51 insertions(+) diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c index 88471d3..34878c9 100644 --- a/drivers/of/of_pci.c +++ b/drivers/of/of_pci.c @@ -2,6 +2,7 @@ #include <linux/export.h> #include <linux/of.h> #include <linux/of_address.h> +#include <linux/of_device.h> #include <linux/of_pci.h> #include <linux/slab.h> @@ -229,6 +230,44 @@ parse_failed: return err; } EXPORT_SYMBOL_GPL(of_pci_get_host_bridge_resources); + +/** + * of_get_pci_root_bridge_parent - get the OF node of the root bridge's parent + * @dev: ptr to pci_dev struct of the pci device + * + * This function will traverse the bus up to the root bus starting with + * the child and return the OF node ptr to root bridge device's parent device. + */ +struct device_node *of_get_pci_root_bridge_parent(struct pci_dev *dev) +{ + struct pci_bus *bus = dev->bus; + struct device *bridge; + + while (!pci_is_root_bus(bus)) + bus = bus->parent; + bridge = bus->bridge; + + return bridge->parent->of_node; +} +EXPORT_SYMBOL_GPL(of_get_pci_root_bridge_parent); + +/** + * of_pci_dma_configure - Setup DMA configuration + * @dev: ptr to pci_dev struct of the pci device + * + * Function to update PCI devices's DMA configuration using the same + * info from the OF node of root host bridge's parent. + */ +void of_pci_dma_configure(struct pci_dev *pci_dev) +{ + struct device *dev = &pci_dev->dev; + struct device_node *parent_np; + + parent_np = of_get_pci_root_bridge_parent(pci_dev); + of_dma_configure(dev, parent_np); +} +EXPORT_SYMBOL_GPL(of_pci_dma_configure); + #endif /* CONFIG_OF_ADDRESS */ #ifdef CONFIG_PCI_MSI diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h index ce0e5ab..0465a2a 100644 --- a/include/linux/of_pci.h +++ b/include/linux/of_pci.h @@ -16,6 +16,8 @@ int of_pci_get_devfn(struct device_node *np); int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin); int of_pci_parse_bus_range(struct device_node *node, struct resource *res); int of_get_pci_domain_nr(struct device_node *node); +struct device_node *of_get_pci_root_bridge_parent(struct pci_dev *dev); +void of_pci_dma_configure(struct pci_dev *pci_dev); #else static inline int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq) { @@ -50,6 +52,16 @@ of_get_pci_domain_nr(struct device_node *node) { return -1; } + +static inline struct device_node +*of_get_pci_root_bridge_parent(struct pci_dev *dev) +{ + return NULL; +} + +static inline void of_pci_dma_configure(struct pci_dev *pci_dev) +{ +} #endif #if defined(CONFIG_OF_ADDRESS) -- 1.7.9.5 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu