diff options
Diffstat (limited to 'arch/mips/mm/dma-default.c')
| -rw-r--r-- | arch/mips/mm/dma-default.c | 189 |
1 files changed, 119 insertions, 70 deletions
diff --git a/arch/mips/mm/dma-default.c b/arch/mips/mm/dma-default.c index 4fc1a0fbe00..44b6dff5aba 100644 --- a/arch/mips/mm/dma-default.c +++ b/arch/mips/mm/dma-default.c @@ -4,7 +4,7 @@ * for more details. * * Copyright (C) 2000 Ani Joshi <ajoshi@unixbox.com> - * Copyright (C) 2000, 2001, 06 Ralf Baechle <ralf@linux-mips.org> + * Copyright (C) 2000, 2001, 06 Ralf Baechle <ralf@linux-mips.org> * swiped from i386, and cloned for MIPS by Geert, polished by Ralf. */ @@ -15,31 +15,58 @@ #include <linux/scatterlist.h> #include <linux/string.h> #include <linux/gfp.h> +#include <linux/highmem.h> #include <asm/cache.h> +#include <asm/cpu-type.h> #include <asm/io.h> #include <dma-coherence.h> -static inline unsigned long dma_addr_to_virt(struct device *dev, - dma_addr_t dma_addr) +#ifdef CONFIG_DMA_MAYBE_COHERENT +int coherentio = 0; /* User defined DMA coherency from command line. */ +EXPORT_SYMBOL_GPL(coherentio); +int hw_coherentio = 0; /* Actual hardware supported DMA coherency setting. */ + +static int __init setcoherentio(char *str) { - unsigned long addr = plat_dma_addr_to_phys(dev, dma_addr); + coherentio = 1; + pr_info("Hardware DMA cache coherency (command line)\n"); + return 0; +} +early_param("coherentio", setcoherentio); - return (unsigned long)phys_to_virt(addr); +static int __init setnocoherentio(char *str) +{ + coherentio = 0; + pr_info("Software DMA cache coherency (command line)\n"); + return 0; +} +early_param("nocoherentio", setnocoherentio); +#endif + +static inline struct page *dma_addr_to_page(struct device *dev, + dma_addr_t dma_addr) +{ + return pfn_to_page( + plat_dma_addr_to_phys(dev, dma_addr) >> PAGE_SHIFT); } /* + * The affected CPUs below in 'cpu_needs_post_dma_flush()' can + * speculatively fill random cachelines with stale data at any time, + * requiring an extra flush post-DMA. + * * Warning on the terminology - Linux calls an uncached area coherent; * MIPS terminology calls memory areas with hardware maintained coherency * coherent. */ - -static inline int cpu_is_noncoherent_r10000(struct device *dev) +static inline int cpu_needs_post_dma_flush(struct device *dev) { return !plat_device_is_coherent(dev) && - (current_cpu_type() == CPU_R10000 || - current_cpu_type() == CPU_R12000); + (boot_cpu_type() == CPU_R10000 || + boot_cpu_type() == CPU_R12000 || + boot_cpu_type() == CPU_BMIPS5000); } static gfp_t massage_gfp_flags(const struct device *dev, gfp_t gfp) @@ -98,7 +125,7 @@ void *dma_alloc_noncoherent(struct device *dev, size_t size, EXPORT_SYMBOL(dma_alloc_noncoherent); static void *mips_dma_alloc_coherent(struct device *dev, size_t size, - dma_addr_t * dma_handle, gfp_t gfp) + dma_addr_t * dma_handle, gfp_t gfp, struct dma_attrs *attrs) { void *ret; @@ -115,7 +142,8 @@ static void *mips_dma_alloc_coherent(struct device *dev, size_t size, if (!plat_device_is_coherent(dev)) { dma_cache_wback_inv((unsigned long) ret, size); - ret = UNCAC_ADDR(ret); + if (!hw_coherentio) + ret = UNCAC_ADDR(ret); } } @@ -132,7 +160,7 @@ void dma_free_noncoherent(struct device *dev, size_t size, void *vaddr, EXPORT_SYMBOL(dma_free_noncoherent); static void mips_dma_free_coherent(struct device *dev, size_t size, void *vaddr, - dma_addr_t dma_handle) + dma_addr_t dma_handle, struct dma_attrs *attrs) { unsigned long addr = (unsigned long) vaddr; int order = get_order(size); @@ -142,26 +170,26 @@ static void mips_dma_free_coherent(struct device *dev, size_t size, void *vaddr, plat_unmap_dma_mem(dev, dma_handle, size, DMA_BIDIRECTIONAL); - if (!plat_device_is_coherent(dev)) + if (!plat_device_is_coherent(dev) && !hw_coherentio) addr = CAC_ADDR(addr); free_pages(addr, get_order(size)); } -static inline void __dma_sync(unsigned long addr, size_t size, +static inline void __dma_sync_virtual(void *addr, size_t size, enum dma_data_direction direction) { switch (direction) { case DMA_TO_DEVICE: - dma_cache_wback(addr, size); + dma_cache_wback((unsigned long)addr, size); break; case DMA_FROM_DEVICE: - dma_cache_inv(addr, size); + dma_cache_inv((unsigned long)addr, size); break; case DMA_BIDIRECTIONAL: - dma_cache_wback_inv(addr, size); + dma_cache_wback_inv((unsigned long)addr, size); break; default: @@ -169,12 +197,49 @@ static inline void __dma_sync(unsigned long addr, size_t size, } } +/* + * A single sg entry may refer to multiple physically contiguous + * pages. But we still need to process highmem pages individually. + * If highmem is not configured then the bulk of this loop gets + * optimized out. + */ +static inline void __dma_sync(struct page *page, + unsigned long offset, size_t size, enum dma_data_direction direction) +{ + size_t left = size; + + do { + size_t len = left; + + if (PageHighMem(page)) { + void *addr; + + if (offset + len > PAGE_SIZE) { + if (offset >= PAGE_SIZE) { + page += offset >> PAGE_SHIFT; + offset &= ~PAGE_MASK; + } + len = PAGE_SIZE - offset; + } + + addr = kmap_atomic(page); + __dma_sync_virtual(addr + offset, len, direction); + kunmap_atomic(addr); + } else + __dma_sync_virtual(page_address(page) + offset, + size, direction); + offset = 0; + page++; + left -= len; + } while (left); +} + static void mips_dma_unmap_page(struct device *dev, dma_addr_t dma_addr, size_t size, enum dma_data_direction direction, struct dma_attrs *attrs) { - if (cpu_is_noncoherent_r10000(dev)) - __dma_sync(dma_addr_to_virt(dev, dma_addr), size, - direction); + if (cpu_needs_post_dma_flush(dev)) + __dma_sync(dma_addr_to_page(dev, dma_addr), + dma_addr & ~PAGE_MASK, size, direction); plat_unmap_dma_mem(dev, dma_addr, size, direction); } @@ -185,13 +250,14 @@ static int mips_dma_map_sg(struct device *dev, struct scatterlist *sg, int i; for (i = 0; i < nents; i++, sg++) { - unsigned long addr; - - addr = (unsigned long) sg_virt(sg); - if (!plat_device_is_coherent(dev) && addr) - __dma_sync(addr, sg->length, direction); - sg->dma_address = plat_map_dma_mem(dev, - (void *)addr, sg->length); + if (!plat_device_is_coherent(dev)) + __dma_sync(sg_page(sg), sg->offset, sg->length, + direction); +#ifdef CONFIG_NEED_SG_DMA_LENGTH + sg->dma_length = sg->length; +#endif + sg->dma_address = plat_map_dma_mem_page(dev, sg_page(sg)) + + sg->offset; } return nents; @@ -201,30 +267,23 @@ static dma_addr_t mips_dma_map_page(struct device *dev, struct page *page, unsigned long offset, size_t size, enum dma_data_direction direction, struct dma_attrs *attrs) { - unsigned long addr; - - addr = (unsigned long) page_address(page) + offset; - if (!plat_device_is_coherent(dev)) - __dma_sync(addr, size, direction); + __dma_sync(page, offset, size, direction); - return plat_map_dma_mem(dev, (void *)addr, size); + return plat_map_dma_mem_page(dev, page) + offset; } static void mips_dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nhwentries, enum dma_data_direction direction, struct dma_attrs *attrs) { - unsigned long addr; int i; for (i = 0; i < nhwentries; i++, sg++) { if (!plat_device_is_coherent(dev) && - direction != DMA_TO_DEVICE) { - addr = (unsigned long) sg_virt(sg); - if (addr) - __dma_sync(addr, sg->length, direction); - } + direction != DMA_TO_DEVICE) + __dma_sync(sg_page(sg), sg->offset, sg->length, + direction); plat_unmap_dma_mem(dev, sg->dma_address, sg->length, direction); } } @@ -232,24 +291,17 @@ static void mips_dma_unmap_sg(struct device *dev, struct scatterlist *sg, static void mips_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction direction) { - if (cpu_is_noncoherent_r10000(dev)) { - unsigned long addr; - - addr = dma_addr_to_virt(dev, dma_handle); - __dma_sync(addr, size, direction); - } + if (cpu_needs_post_dma_flush(dev)) + __dma_sync(dma_addr_to_page(dev, dma_handle), + dma_handle & ~PAGE_MASK, size, direction); } static void mips_dma_sync_single_for_device(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction direction) { - plat_extra_sync_for_device(dev); - if (!plat_device_is_coherent(dev)) { - unsigned long addr; - - addr = dma_addr_to_virt(dev, dma_handle); - __dma_sync(addr, size, direction); - } + if (!plat_device_is_coherent(dev)) + __dma_sync(dma_addr_to_page(dev, dma_handle), + dma_handle & ~PAGE_MASK, size, direction); } static void mips_dma_sync_sg_for_cpu(struct device *dev, @@ -257,12 +309,10 @@ static void mips_dma_sync_sg_for_cpu(struct device *dev, { int i; - /* Make sure that gcc doesn't leave the empty loop body. */ - for (i = 0; i < nelems; i++, sg++) { - if (cpu_is_noncoherent_r10000(dev)) - __dma_sync((unsigned long)page_address(sg_page(sg)), - sg->length, direction); - } + if (cpu_needs_post_dma_flush(dev)) + for (i = 0; i < nelems; i++, sg++) + __dma_sync(sg_page(sg), sg->offset, sg->length, + direction); } static void mips_dma_sync_sg_for_device(struct device *dev, @@ -270,17 +320,15 @@ static void mips_dma_sync_sg_for_device(struct device *dev, { int i; - /* Make sure that gcc doesn't leave the empty loop body. */ - for (i = 0; i < nelems; i++, sg++) { - if (!plat_device_is_coherent(dev)) - __dma_sync((unsigned long)page_address(sg_page(sg)), - sg->length, direction); - } + if (!plat_device_is_coherent(dev)) + for (i = 0; i < nelems; i++, sg++) + __dma_sync(sg_page(sg), sg->offset, sg->length, + direction); } int mips_dma_mapping_error(struct device *dev, dma_addr_t dma_addr) { - return plat_dma_mapping_error(dev, dma_addr); + return 0; } int mips_dma_supported(struct device *dev, u64 mask) @@ -288,19 +336,20 @@ int mips_dma_supported(struct device *dev, u64 mask) return plat_dma_supported(dev, mask); } -void mips_dma_cache_sync(struct device *dev, void *vaddr, size_t size, +void dma_cache_sync(struct device *dev, void *vaddr, size_t size, enum dma_data_direction direction) { BUG_ON(direction == DMA_NONE); - plat_extra_sync_for_device(dev); if (!plat_device_is_coherent(dev)) - __dma_sync((unsigned long)vaddr, size, direction); + __dma_sync_virtual(vaddr, size, direction); } +EXPORT_SYMBOL(dma_cache_sync); + static struct dma_map_ops mips_default_dma_map_ops = { - .alloc_coherent = mips_dma_alloc_coherent, - .free_coherent = mips_dma_free_coherent, + .alloc = mips_dma_alloc_coherent, + .free = mips_dma_free_coherent, .map_page = mips_dma_map_page, .unmap_page = mips_dma_unmap_page, .map_sg = mips_dma_map_sg, |