| /* |
| * arch/sh/mm/consistent.c |
| * |
| * 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. |
| */ |
| #include <linux/mm.h> |
| #include <linux/init.h> |
| #include <linux/platform_device.h> |
| #include <linux/dma-mapping.h> |
| #include <linux/dma-debug.h> |
| #include <linux/io.h> |
| #include <linux/module.h> |
| #include <linux/gfp.h> |
| #include <asm/cacheflush.h> |
| #include <asm/addrspace.h> |
| |
| #define PREALLOC_DMA_DEBUG_ENTRIES 4096 |
| |
| const struct dma_map_ops *dma_ops; |
| EXPORT_SYMBOL(dma_ops); |
| |
| static int __init dma_init(void) |
| { |
| dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES); |
| return 0; |
| } |
| fs_initcall(dma_init); |
| |
| void *dma_generic_alloc_coherent(struct device *dev, size_t size, |
| dma_addr_t *dma_handle, gfp_t gfp, |
| unsigned long attrs) |
| { |
| void *ret, *ret_nocache; |
| int order = get_order(size); |
| |
| gfp |= __GFP_ZERO; |
| |
| ret = (void *)__get_free_pages(gfp, order); |
| if (!ret) |
| return NULL; |
| |
| /* |
| * Pages from the page allocator may have data present in |
| * cache. So flush the cache before using uncached memory. |
| */ |
| sh_sync_dma_for_device(ret, size, DMA_BIDIRECTIONAL); |
| |
| ret_nocache = (void __force *)ioremap_nocache(virt_to_phys(ret), size); |
| if (!ret_nocache) { |
| free_pages((unsigned long)ret, order); |
| return NULL; |
| } |
| |
| split_page(pfn_to_page(virt_to_phys(ret) >> PAGE_SHIFT), order); |
| |
| *dma_handle = virt_to_phys(ret); |
| if (!WARN_ON(!dev)) |
| *dma_handle -= PFN_PHYS(dev->dma_pfn_offset); |
| |
| return ret_nocache; |
| } |
| |
| void dma_generic_free_coherent(struct device *dev, size_t size, |
| void *vaddr, dma_addr_t dma_handle, |
| unsigned long attrs) |
| { |
| int order = get_order(size); |
| unsigned long pfn = dma_handle >> PAGE_SHIFT; |
| int k; |
| |
| if (!WARN_ON(!dev)) |
| pfn += dev->dma_pfn_offset; |
| |
| for (k = 0; k < (1 << order); k++) |
| __free_pages(pfn_to_page(pfn + k), 0); |
| |
| iounmap(vaddr); |
| } |
| |
| void sh_sync_dma_for_device(void *vaddr, size_t size, |
| enum dma_data_direction direction) |
| { |
| void *addr; |
| |
| addr = __in_29bit_mode() ? |
| (void *)CAC_ADDR((unsigned long)vaddr) : vaddr; |
| |
| switch (direction) { |
| case DMA_FROM_DEVICE: /* invalidate only */ |
| __flush_invalidate_region(addr, size); |
| break; |
| case DMA_TO_DEVICE: /* writeback only */ |
| __flush_wback_region(addr, size); |
| break; |
| case DMA_BIDIRECTIONAL: /* writeback and invalidate */ |
| __flush_purge_region(addr, size); |
| break; |
| default: |
| BUG(); |
| } |
| } |
| EXPORT_SYMBOL(sh_sync_dma_for_device); |
| |
| static int __init memchunk_setup(char *str) |
| { |
| return 1; /* accept anything that begins with "memchunk." */ |
| } |
| __setup("memchunk.", memchunk_setup); |
| |
| static void __init memchunk_cmdline_override(char *name, unsigned long *sizep) |
| { |
| char *p = boot_command_line; |
| int k = strlen(name); |
| |
| while ((p = strstr(p, "memchunk."))) { |
| p += 9; /* strlen("memchunk.") */ |
| if (!strncmp(name, p, k) && p[k] == '=') { |
| p += k + 1; |
| *sizep = memparse(p, NULL); |
| pr_info("%s: forcing memory chunk size to 0x%08lx\n", |
| name, *sizep); |
| break; |
| } |
| } |
| } |
| |
| int __init platform_resource_setup_memory(struct platform_device *pdev, |
| char *name, unsigned long memsize) |
| { |
| struct resource *r; |
| dma_addr_t dma_handle; |
| void *buf; |
| |
| r = pdev->resource + pdev->num_resources - 1; |
| if (r->flags) { |
| pr_warning("%s: unable to find empty space for resource\n", |
| name); |
| return -EINVAL; |
| } |
| |
| memchunk_cmdline_override(name, &memsize); |
| if (!memsize) |
| return 0; |
| |
| buf = dma_alloc_coherent(&pdev->dev, memsize, &dma_handle, GFP_KERNEL); |
| if (!buf) { |
| pr_warning("%s: unable to allocate memory\n", name); |
| return -ENOMEM; |
| } |
| |
| memset(buf, 0, memsize); |
| |
| r->flags = IORESOURCE_MEM; |
| r->start = dma_handle; |
| r->end = r->start + memsize - 1; |
| r->name = name; |
| return 0; |
| } |