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Diffstat (limited to '')
-rw-r--r-- | arch/nios2/mm/dma-mapping.c | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/arch/nios2/mm/dma-mapping.c b/arch/nios2/mm/dma-mapping.c new file mode 100644 index 000000000..4af9e5b5b --- /dev/null +++ b/arch/nios2/mm/dma-mapping.c @@ -0,0 +1,91 @@ +/* + * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch> + * Copyright (C) 2009 Wind River Systems Inc + * Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com + * + * Based on DMA code from MIPS. + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ + +#include <linux/types.h> +#include <linux/mm.h> +#include <linux/string.h> +#include <linux/dma-mapping.h> +#include <linux/io.h> +#include <linux/cache.h> +#include <asm/cacheflush.h> + +void arch_sync_dma_for_device(struct device *dev, phys_addr_t paddr, + size_t size, enum dma_data_direction dir) +{ + void *vaddr = phys_to_virt(paddr); + + switch (dir) { + case DMA_FROM_DEVICE: + invalidate_dcache_range((unsigned long)vaddr, + (unsigned long)(vaddr + size)); + break; + case DMA_TO_DEVICE: + /* + * We just need to flush the caches here , but Nios2 flush + * instruction will do both writeback and invalidate. + */ + case DMA_BIDIRECTIONAL: /* flush and invalidate */ + flush_dcache_range((unsigned long)vaddr, + (unsigned long)(vaddr + size)); + break; + default: + BUG(); + } +} + +void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr, + size_t size, enum dma_data_direction dir) +{ + void *vaddr = phys_to_virt(paddr); + + switch (dir) { + case DMA_BIDIRECTIONAL: + case DMA_FROM_DEVICE: + invalidate_dcache_range((unsigned long)vaddr, + (unsigned long)(vaddr + size)); + break; + case DMA_TO_DEVICE: + break; + default: + BUG(); + } +} + +void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, + gfp_t gfp, unsigned long attrs) +{ + void *ret; + + /* optimized page clearing */ + gfp |= __GFP_ZERO; + + if (dev == NULL || (dev->coherent_dma_mask < 0xffffffff)) + gfp |= GFP_DMA; + + ret = (void *) __get_free_pages(gfp, get_order(size)); + if (ret != NULL) { + *dma_handle = virt_to_phys(ret); + flush_dcache_range((unsigned long) ret, + (unsigned long) ret + size); + ret = UNCAC_ADDR(ret); + } + + return ret; +} + +void arch_dma_free(struct device *dev, size_t size, void *vaddr, + dma_addr_t dma_handle, unsigned long attrs) +{ + unsigned long addr = (unsigned long) CAC_ADDR((unsigned long) vaddr); + + free_pages(addr, get_order(size)); +} |