diff options
Diffstat (limited to 'arch/frv/mb93090-mb00/pci-dma.c')
-rw-r--r-- | arch/frv/mb93090-mb00/pci-dma.c | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/arch/frv/mb93090-mb00/pci-dma.c b/arch/frv/mb93090-mb00/pci-dma.c new file mode 100644 index 000000000000..27eb12066507 --- /dev/null +++ b/arch/frv/mb93090-mb00/pci-dma.c @@ -0,0 +1,105 @@ +/* pci-dma.c: Dynamic DMA mapping support for the FRV CPUs that have MMUs + * + * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/dma-mapping.h> +#include <linux/list.h> +#include <linux/pci.h> +#include <linux/highmem.h> +#include <asm/io.h> + +void *dma_alloc_coherent(struct device *hwdev, size_t size, dma_addr_t *dma_handle, int gfp) +{ + void *ret; + + ret = consistent_alloc(gfp, size, dma_handle); + if (ret) + memset(ret, 0, size); + + return ret; +} + +void dma_free_coherent(struct device *hwdev, size_t size, void *vaddr, dma_addr_t dma_handle) +{ + consistent_free(vaddr); +} + +/* + * Map a single buffer of the indicated size for DMA in streaming mode. + * The 32-bit bus address to use is returned. + * + * Once the device is given the dma address, the device owns this memory + * until either pci_unmap_single or pci_dma_sync_single is performed. + */ +dma_addr_t dma_map_single(struct device *dev, void *ptr, size_t size, + enum dma_data_direction direction) +{ + if (direction == DMA_NONE) + BUG(); + + frv_cache_wback_inv((unsigned long) ptr, (unsigned long) ptr + size); + + return virt_to_bus(ptr); +} + +/* + * Map a set of buffers described by scatterlist in streaming + * mode for DMA. This is the scather-gather version of the + * above pci_map_single interface. Here the scatter gather list + * elements are each tagged with the appropriate dma address + * and length. They are obtained via sg_dma_{address,length}(SG). + * + * NOTE: An implementation may be able to use a smaller number of + * DMA address/length pairs than there are SG table elements. + * (for example via virtual mapping capabilities) + * The routine returns the number of addr/length pairs actually + * used, at most nents. + * + * Device ownership issues as mentioned above for pci_map_single are + * the same here. + */ +int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents, + enum dma_data_direction direction) +{ + unsigned long dampr2; + void *vaddr; + int i; + + if (direction == DMA_NONE) + BUG(); + + dampr2 = __get_DAMPR(2); + + for (i = 0; i < nents; i++) { + vaddr = kmap_atomic(sg[i].page, __KM_CACHE); + + frv_dcache_writeback((unsigned long) vaddr, + (unsigned long) vaddr + PAGE_SIZE); + + } + + kunmap_atomic(vaddr, __KM_CACHE); + if (dampr2) { + __set_DAMPR(2, dampr2); + __set_IAMPR(2, dampr2); + } + + return nents; +} + +dma_addr_t dma_map_page(struct device *dev, struct page *page, unsigned long offset, + size_t size, enum dma_data_direction direction) +{ + BUG_ON(direction == DMA_NONE); + flush_dcache_page(page); + return (dma_addr_t) page_to_phys(page) + offset; +} |