diff options
Diffstat (limited to 'arch/sh')
| -rw-r--r-- | arch/sh/mm/consistent.c | 174 |
1 files changed, 128 insertions, 46 deletions
diff --git a/arch/sh/mm/consistent.c b/arch/sh/mm/consistent.c index 65ad30031ad7..7b2131c9eeda 100644 --- a/arch/sh/mm/consistent.c +++ b/arch/sh/mm/consistent.c @@ -3,6 +3,8 @@ * * Copyright (C) 2004 - 2007 Paul Mundt * + * Declared coherent memory functions based on arch/x86/kernel/pci-dma_32.c + * * 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. @@ -13,66 +15,146 @@ #include <asm/addrspace.h> #include <asm/io.h> -void *consistent_alloc(gfp_t gfp, size_t size, dma_addr_t *handle) -{ - struct page *page, *end, *free; - void *ret, *vp; - int order; - - size = PAGE_ALIGN(size); - order = get_order(size); +struct dma_coherent_mem { + void *virt_base; + u32 device_base; + int size; + int flags; + unsigned long *bitmap; +}; - page = alloc_pages(gfp, order); - if (!page) - return NULL; - split_page(page, order); +void *dma_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp) +{ + void *ret; + struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL; + int order = get_order(size); + + if (mem) { + int page = bitmap_find_free_region(mem->bitmap, mem->size, + order); + if (page >= 0) { + *dma_handle = mem->device_base + (page << PAGE_SHIFT); + ret = mem->virt_base + (page << PAGE_SHIFT); + memset(ret, 0, size); + return ret; + } + if (mem->flags & DMA_MEMORY_EXCLUSIVE) + return NULL; + } - ret = page_address(page); - *handle = virt_to_phys(ret); + ret = (void *)__get_free_pages(gfp, order); - vp = ioremap_nocache(*handle, size); - if (!vp) { - free_pages((unsigned long)ret, order); - return NULL; + if (ret != NULL) { + memset(ret, 0, size); + /* + * Pages from the page allocator may have data present in + * cache. So flush the cache before using uncached memory. + */ + dma_cache_sync(NULL, ret, size, DMA_BIDIRECTIONAL); + *dma_handle = virt_to_phys(ret); } + return ret; +} +EXPORT_SYMBOL(dma_alloc_coherent); - memset(vp, 0, size); - - /* - * We must flush the cache before we pass it on to the device - */ - dma_cache_sync(NULL, ret, size, DMA_BIDIRECTIONAL); +void dma_free_coherent(struct device *dev, size_t size, + void *vaddr, dma_addr_t dma_handle) +{ + struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL; + int order = get_order(size); - page = virt_to_page(ret); - free = page + (size >> PAGE_SHIFT); - end = page + (1 << order); + if (mem && vaddr >= mem->virt_base && vaddr < (mem->virt_base + (mem->size << PAGE_SHIFT))) { + int page = (vaddr - mem->virt_base) >> PAGE_SHIFT; - while (++page < end) { - /* Free any unused pages */ - if (page >= free) { - __free_page(page); - } + bitmap_release_region(mem->bitmap, page, order); + } else { + WARN_ON(irqs_disabled()); /* for portability */ + BUG_ON(mem && mem->flags & DMA_MEMORY_EXCLUSIVE); + free_pages((unsigned long)vaddr, order); } - - return vp; } -EXPORT_SYMBOL(consistent_alloc); +EXPORT_SYMBOL(dma_free_coherent); -void consistent_free(void *vaddr, size_t size, dma_addr_t dma_handle) +int dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr, + dma_addr_t device_addr, size_t size, int flags) { - struct page *page; - unsigned long addr; - - addr = (unsigned long)phys_to_virt((unsigned long)dma_handle); - page = virt_to_page(addr); + void __iomem *mem_base = NULL; + int pages = size >> PAGE_SHIFT; + int bitmap_size = BITS_TO_LONGS(pages) * sizeof(long); + + if ((flags & (DMA_MEMORY_MAP | DMA_MEMORY_IO)) == 0) + goto out; + if (!size) + goto out; + if (dev->dma_mem) + goto out; + + /* FIXME: this routine just ignores DMA_MEMORY_INCLUDES_CHILDREN */ + + mem_base = ioremap_nocache(bus_addr, size); + if (!mem_base) + goto out; + + dev->dma_mem = kmalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL); + if (!dev->dma_mem) + goto out; + dev->dma_mem->bitmap = kzalloc(bitmap_size, GFP_KERNEL); + if (!dev->dma_mem->bitmap) + goto free1_out; + + dev->dma_mem->virt_base = mem_base; + dev->dma_mem->device_base = device_addr; + dev->dma_mem->size = pages; + dev->dma_mem->flags = flags; + + if (flags & DMA_MEMORY_MAP) + return DMA_MEMORY_MAP; + + return DMA_MEMORY_IO; + + free1_out: + kfree(dev->dma_mem); + out: + if (mem_base) + iounmap(mem_base); + return 0; +} +EXPORT_SYMBOL(dma_declare_coherent_memory); - free_pages(addr, get_order(size)); +void dma_release_declared_memory(struct device *dev) +{ + struct dma_coherent_mem *mem = dev->dma_mem; + + if (!mem) + return; + dev->dma_mem = NULL; + iounmap(mem->virt_base); + kfree(mem->bitmap); + kfree(mem); +} +EXPORT_SYMBOL(dma_release_declared_memory); - iounmap(vaddr); +void *dma_mark_declared_memory_occupied(struct device *dev, + dma_addr_t device_addr, size_t size) +{ + struct dma_coherent_mem *mem = dev->dma_mem; + int pages = (size + (device_addr & ~PAGE_MASK) + PAGE_SIZE - 1) >> PAGE_SHIFT; + int pos, err; + + if (!mem) + return ERR_PTR(-EINVAL); + + pos = (device_addr - mem->device_base) >> PAGE_SHIFT; + err = bitmap_allocate_region(mem->bitmap, pos, get_order(pages)); + if (err != 0) + return ERR_PTR(err); + return mem->virt_base + (pos << PAGE_SHIFT); } -EXPORT_SYMBOL(consistent_free); +EXPORT_SYMBOL(dma_mark_declared_memory_occupied); -void consistent_sync(void *vaddr, size_t size, int direction) +void dma_cache_sync(struct device *dev, void *vaddr, size_t size, + enum dma_data_direction direction) { #ifdef CONFIG_CPU_SH5 void *p1addr = vaddr; @@ -94,4 +176,4 @@ void consistent_sync(void *vaddr, size_t size, int direction) BUG(); } } -EXPORT_SYMBOL(consistent_sync); +EXPORT_SYMBOL(dma_cache_sync); |