diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-11-23 01:35:55 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-11-23 01:35:55 -0300 |
commit | d26f4ddb48463e2ff798859505af1cc520e75685 (patch) | |
tree | a1268534c14d9a7db61b4758ac72c33a3c7712bb /arch/arc/mm/dma.c | |
parent | 3326a1803802aa4730d32304b003f50720996b31 (diff) |
Linux-libre 4.8.10-gnupck-4.8.10-gnu
Diffstat (limited to 'arch/arc/mm/dma.c')
-rw-r--r-- | arch/arc/mm/dma.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/arch/arc/mm/dma.c b/arch/arc/mm/dma.c index 20afc65e2..9288851d4 100644 --- a/arch/arc/mm/dma.c +++ b/arch/arc/mm/dma.c @@ -105,6 +105,31 @@ static void arc_dma_free(struct device *dev, size_t size, void *vaddr, __free_pages(page, get_order(size)); } +static int arc_dma_mmap(struct device *dev, struct vm_area_struct *vma, + void *cpu_addr, dma_addr_t dma_addr, size_t size, + unsigned long attrs) +{ + unsigned long user_count = vma_pages(vma); + unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT; + unsigned long pfn = __phys_to_pfn(plat_dma_to_phys(dev, dma_addr)); + unsigned long off = vma->vm_pgoff; + int ret = -ENXIO; + + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); + + if (dma_mmap_from_coherent(dev, vma, cpu_addr, size, &ret)) + return ret; + + if (off < count && user_count <= (count - off)) { + ret = remap_pfn_range(vma, vma->vm_start, + pfn + off, + user_count << PAGE_SHIFT, + vma->vm_page_prot); + } + + return ret; +} + /* * streaming DMA Mapping API... * CPU accesses page via normal paddr, thus needs to explicitly made @@ -193,6 +218,7 @@ static int arc_dma_supported(struct device *dev, u64 dma_mask) struct dma_map_ops arc_dma_ops = { .alloc = arc_dma_alloc, .free = arc_dma_free, + .mmap = arc_dma_mmap, .map_page = arc_dma_map_page, .map_sg = arc_dma_map_sg, .sync_single_for_device = arc_dma_sync_single_for_device, |