If a device is not behind an IOMMU, we look up the device node and set up the restricted DMA when the restricted-dma-pool is presented.
Signed-off-by: Claire Chang tientzu@chromium.org --- drivers/of/address.c | 33 +++++++++++++++++++++++++++++++++ drivers/of/device.c | 3 +++ drivers/of/of_private.h | 6 ++++++ 3 files changed, 42 insertions(+)
diff --git a/drivers/of/address.c b/drivers/of/address.c index 3b2acca7e363..c8066d95ff0e 100644 --- a/drivers/of/address.c +++ b/drivers/of/address.c @@ -8,6 +8,7 @@ #include <linux/logic_pio.h> #include <linux/module.h> #include <linux/of_address.h> +#include <linux/of_reserved_mem.h> #include <linux/pci.h> #include <linux/pci_regs.h> #include <linux/sizes.h> @@ -1001,6 +1002,38 @@ int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map) of_node_put(node); return ret; } + +int of_dma_set_restricted_buffer(struct device *dev, struct device_node *np) +{ + struct device_node *node, *of_node = dev->of_node; + int count, i; + + count = of_property_count_elems_of_size(of_node, "memory-region", + sizeof(u32)); + /* + * If dev->of_node doesn't exist or doesn't contain memory-region, try + * the OF node having DMA configuration. + */ + if (count <= 0) { + of_node = np; + count = of_property_count_elems_of_size( + of_node, "memory-region", sizeof(u32)); + } + + for (i = 0; i < count; i++) { + node = of_parse_phandle(of_node, "memory-region", i); + /* + * There might be multiple memory regions, but only one + * restricted-dma-pool region is allowed. + */ + if (of_device_is_compatible(node, "restricted-dma-pool") && + of_device_is_available(node)) + return of_reserved_mem_device_init_by_idx(dev, of_node, + i); + } + + return 0; +} #endif /* CONFIG_HAS_DMA */
/** diff --git a/drivers/of/device.c b/drivers/of/device.c index 1defdf15ba95..ba4656e77502 100644 --- a/drivers/of/device.c +++ b/drivers/of/device.c @@ -168,6 +168,9 @@ int of_dma_configure_id(struct device *dev, struct device_node *np, if (IS_ENABLED(CONFIG_SWIOTLB)) swiotlb_set_io_tlb_default_mem(dev);
+ if (!iommu) + return of_dma_set_restricted_buffer(dev, np); + return 0; } EXPORT_SYMBOL_GPL(of_dma_configure_id); diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h index 631489f7f8c0..376462798f7e 100644 --- a/drivers/of/of_private.h +++ b/drivers/of/of_private.h @@ -163,12 +163,18 @@ struct bus_dma_region; #if defined(CONFIG_OF_ADDRESS) && defined(CONFIG_HAS_DMA) int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map); +int of_dma_set_restricted_buffer(struct device *dev, struct device_node *np); #else static inline int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map) { return -ENODEV; } +static inline int of_dma_set_restricted_buffer(struct device *dev, + struct device_node *np) +{ + return -ENODEV; +} #endif
void fdt_init_reserved_mem(void);