In order to support IOMMUs in non-bypass mode we need device ops to map and unmap DMA memory. The map operation enters a mapping for a region specified by CPU address and size into the translation table of the IOMMU and returns a DMA address suitable for programming the device to do DMA. The unmap operation removes this mapping from the translation table of the IOMMU.
Signed-off-by: Mark Kettenis kettenis@openbsd.org --- drivers/iommu/iommu-uclass.c | 28 ++++++++++++++++++++++++++++ include/dm/device.h | 3 +++ include/iommu.h | 24 ++++++++++++++++++++++++ 3 files changed, 55 insertions(+)
diff --git a/drivers/iommu/iommu-uclass.c b/drivers/iommu/iommu-uclass.c index ed917b3c3e..f6b1457736 100644 --- a/drivers/iommu/iommu-uclass.c +++ b/drivers/iommu/iommu-uclass.c @@ -7,6 +7,9 @@
#include <common.h> #include <dm.h> +#include <iommu.h> +#include <phys2bus.h> +#include <asm/io.h>
#if (CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)) int dev_iommu_enable(struct udevice *dev) @@ -33,12 +36,37 @@ int dev_iommu_enable(struct udevice *dev) __func__, ret); return ret; } + dev->iommu = dev_iommu; }
return 0; } #endif
+dma_addr_t dev_iommu_dma_map(struct udevice *dev, void *addr, size_t size) +{ + const struct iommu_ops *ops; + + if (dev->iommu) { + ops = device_get_ops(dev->iommu); + if (ops && ops->map) + return ops->map(dev->iommu, addr, size); + } + + return dev_phys_to_bus(dev, virt_to_phys(addr)); +} + +void dev_iommu_dma_unmap(struct udevice *dev, dma_addr_t addr, size_t size) +{ + const struct iommu_ops *ops; + + if (dev->iommu) { + ops = device_get_ops(dev->iommu); + if (ops && ops->unmap) + ops->unmap(dev->iommu, addr, size); + } +} + UCLASS_DRIVER(iommu) = { .id = UCLASS_IOMMU, .name = "iommu", diff --git a/include/dm/device.h b/include/dm/device.h index f3f953c9af..abe1927ecd 100644 --- a/include/dm/device.h +++ b/include/dm/device.h @@ -194,6 +194,9 @@ struct udevice { #if CONFIG_IS_ENABLED(DM_DMA) ulong dma_offset; #endif +#if CONFIG_IS_ENABLED(IOMMU) + struct udevice *iommu; +#endif };
static inline int dm_udevice_size(void) diff --git a/include/iommu.h b/include/iommu.h index 6c46adf449..cf9719c5e9 100644 --- a/include/iommu.h +++ b/include/iommu.h @@ -3,6 +3,27 @@
struct udevice;
+struct iommu_ops { + /** + * map() - map DMA memory + * + * @dev: device for which to map DMA memory + * @addr: CPU address of the memory + * @size: size of the memory + * @return DMA address for the device + */ + dma_addr_t (*map)(struct udevice *dev, void *addr, size_t size); + + /** + * unmap() - unmap DMA memory + * + * @dev: device for which to unmap DMA memory + * @addr: DMA address of the memory + * @size: size of the memory + */ + void (*unmap)(struct udevice *dev, dma_addr_t addr, size_t size); +}; + #if (CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)) && \ CONFIG_IS_ENABLED(IOMMU) int dev_iommu_enable(struct udevice *dev); @@ -13,4 +34,7 @@ static inline int dev_iommu_enable(struct udevice *dev) } #endif
+dma_addr_t dev_iommu_dma_map(struct udevice *dev, void *addr, size_t size); +void dev_iommu_dma_unmap(struct udevice *dev, dma_addr_t addr, size_t size); + #endif