130 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			130 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * This file is subject to the terms and conditions of the GNU General Public
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|  * License.  See the file COPYING in the main directory of this archive
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|  * for more details.
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|  */
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| 
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| #undef DEBUG
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| 
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| #include <linux/dma-mapping.h>
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| #include <linux/device.h>
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| #include <linux/kernel.h>
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| #include <linux/scatterlist.h>
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| #include <linux/vmalloc.h>
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| 
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| #include <asm/pgalloc.h>
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| 
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| void *dma_alloc_coherent(struct device *dev, size_t size,
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| 			 dma_addr_t *handle, gfp_t flag)
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| {
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| 	struct page *page, **map;
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| 	pgprot_t pgprot;
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| 	void *addr;
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| 	int i, order;
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| 
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| 	pr_debug("dma_alloc_coherent: %d,%x\n", size, flag);
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| 
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| 	size = PAGE_ALIGN(size);
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| 	order = get_order(size);
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| 
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| 	page = alloc_pages(flag, order);
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| 	if (!page)
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| 		return NULL;
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| 
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| 	*handle = page_to_phys(page);
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| 	map = kmalloc(sizeof(struct page *) << order, flag & ~__GFP_DMA);
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| 	if (!map) {
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| 		__free_pages(page, order);
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| 		return NULL;
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| 	}
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| 	split_page(page, order);
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| 
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| 	order = 1 << order;
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| 	size >>= PAGE_SHIFT;
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| 	map[0] = page;
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| 	for (i = 1; i < size; i++)
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| 		map[i] = page + i;
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| 	for (; i < order; i++)
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| 		__free_page(page + i);
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| 	pgprot = __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY);
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| 	if (CPU_IS_040_OR_060)
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| 		pgprot_val(pgprot) |= _PAGE_GLOBAL040 | _PAGE_NOCACHE_S;
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| 	else
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| 		pgprot_val(pgprot) |= _PAGE_NOCACHE030;
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| 	addr = vmap(map, size, VM_MAP, pgprot);
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| 	kfree(map);
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| 
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| 	return addr;
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| }
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| EXPORT_SYMBOL(dma_alloc_coherent);
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| 
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| void dma_free_coherent(struct device *dev, size_t size,
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| 		       void *addr, dma_addr_t handle)
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| {
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| 	pr_debug("dma_free_coherent: %p, %x\n", addr, handle);
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| 	vfree(addr);
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| }
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| EXPORT_SYMBOL(dma_free_coherent);
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| 
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| void dma_sync_single_for_device(struct device *dev, dma_addr_t handle,
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| 				size_t size, enum dma_data_direction dir)
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| {
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| 	switch (dir) {
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| 	case DMA_TO_DEVICE:
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| 		cache_push(handle, size);
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| 		break;
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| 	case DMA_FROM_DEVICE:
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| 		cache_clear(handle, size);
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| 		break;
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| 	default:
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| 		if (printk_ratelimit())
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| 			printk("dma_sync_single_for_device: unsupported dir %u\n", dir);
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| 		break;
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| 	}
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| }
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| EXPORT_SYMBOL(dma_sync_single_for_device);
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| 
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| void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nents,
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| 			    enum dma_data_direction dir)
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| {
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| 	int i;
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| 
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| 	for (i = 0; i < nents; sg++, i++)
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| 		dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir);
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| }
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| EXPORT_SYMBOL(dma_sync_sg_for_device);
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| 
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| dma_addr_t dma_map_single(struct device *dev, void *addr, size_t size,
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| 			  enum dma_data_direction dir)
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| {
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| 	dma_addr_t handle = virt_to_bus(addr);
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| 
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| 	dma_sync_single_for_device(dev, handle, size, dir);
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| 	return handle;
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| }
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| EXPORT_SYMBOL(dma_map_single);
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| 
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| dma_addr_t dma_map_page(struct device *dev, struct page *page,
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| 			unsigned long offset, size_t size,
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| 			enum dma_data_direction dir)
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| {
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| 	dma_addr_t handle = page_to_phys(page) + offset;
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| 
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| 	dma_sync_single_for_device(dev, handle, size, dir);
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| 	return handle;
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| }
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| EXPORT_SYMBOL(dma_map_page);
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| 
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| int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
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| 	       enum dma_data_direction dir)
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| {
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| 	int i;
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| 
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| 	for (i = 0; i < nents; sg++, i++) {
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| 		sg->dma_address = sg_phys(sg);
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| 		dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir);
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| 	}
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| 	return nents;
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| }
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| EXPORT_SYMBOL(dma_map_sg);
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