diff options
Diffstat (limited to 'arch/arm/xen/mm.c')
-rw-r--r-- | arch/arm/xen/mm.c | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/arch/arm/xen/mm.c b/arch/arm/xen/mm.c index b0e77de99148..ab700e1e5922 100644 --- a/arch/arm/xen/mm.c +++ b/arch/arm/xen/mm.c @@ -1,6 +1,10 @@ +#include <linux/cpu.h> +#include <linux/dma-mapping.h> #include <linux/bootmem.h> #include <linux/gfp.h> +#include <linux/highmem.h> #include <linux/export.h> +#include <linux/of_address.h> #include <linux/slab.h> #include <linux/types.h> #include <linux/dma-mapping.h> @@ -16,6 +20,86 @@ #include <asm/xen/hypercall.h> #include <asm/xen/interface.h> +enum dma_cache_op { + DMA_UNMAP, + DMA_MAP, +}; + +/* functions called by SWIOTLB */ + +static void dma_cache_maint(dma_addr_t handle, unsigned long offset, + size_t size, enum dma_data_direction dir, enum dma_cache_op op) +{ + unsigned long pfn; + size_t left = size; + + pfn = (handle >> PAGE_SHIFT) + offset / PAGE_SIZE; + offset %= PAGE_SIZE; + + do { + size_t len = left; + + /* TODO: cache flush */ + + offset = 0; + pfn++; + left -= len; + } while (left); +} + +static void __xen_dma_page_dev_to_cpu(struct device *hwdev, dma_addr_t handle, + size_t size, enum dma_data_direction dir) +{ + dma_cache_maint(handle & PAGE_MASK, handle & ~PAGE_MASK, size, dir, DMA_UNMAP); +} + +static void __xen_dma_page_cpu_to_dev(struct device *hwdev, dma_addr_t handle, + size_t size, enum dma_data_direction dir) +{ + dma_cache_maint(handle & PAGE_MASK, handle & ~PAGE_MASK, size, dir, DMA_MAP); +} + +void __xen_dma_map_page(struct device *hwdev, struct page *page, + dma_addr_t dev_addr, unsigned long offset, size_t size, + enum dma_data_direction dir, struct dma_attrs *attrs) +{ + if (is_device_dma_coherent(hwdev)) + return; + if (dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs)) + return; + + __xen_dma_page_cpu_to_dev(hwdev, dev_addr, size, dir); +} + +void __xen_dma_unmap_page(struct device *hwdev, dma_addr_t handle, + size_t size, enum dma_data_direction dir, + struct dma_attrs *attrs) + +{ + if (is_device_dma_coherent(hwdev)) + return; + if (dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs)) + return; + + __xen_dma_page_dev_to_cpu(hwdev, handle, size, dir); +} + +void __xen_dma_sync_single_for_cpu(struct device *hwdev, + dma_addr_t handle, size_t size, enum dma_data_direction dir) +{ + if (is_device_dma_coherent(hwdev)) + return; + __xen_dma_page_dev_to_cpu(hwdev, handle, size, dir); +} + +void __xen_dma_sync_single_for_device(struct device *hwdev, + dma_addr_t handle, size_t size, enum dma_data_direction dir) +{ + if (is_device_dma_coherent(hwdev)) + return; + __xen_dma_page_cpu_to_dev(hwdev, handle, size, dir); +} + int xen_create_contiguous_region(phys_addr_t pstart, unsigned int order, unsigned int address_bits, dma_addr_t *dma_handle) |