1 /* pci-dma.c: Dynamic DMA mapping support for the FRV CPUs that have MMUs
2  *
3  * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
4  * Written by David Howells (dhowells@redhat.com)
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version
9  * 2 of the License, or (at your option) any later version.
10  */
11 
12 #include <linux/types.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/list.h>
15 #include <linux/pci.h>
16 #include <linux/highmem.h>
17 #include <linux/scatterlist.h>
18 #include <asm/io.h>
19 
dma_alloc_coherent(struct device * hwdev,size_t size,dma_addr_t * dma_handle,gfp_t gfp)20 void *dma_alloc_coherent(struct device *hwdev, size_t size, dma_addr_t *dma_handle, gfp_t gfp)
21 {
22 	void *ret;
23 
24 	ret = consistent_alloc(gfp, size, dma_handle);
25 	if (ret)
26 		memset(ret, 0, size);
27 
28 	return ret;
29 }
30 
31 EXPORT_SYMBOL(dma_alloc_coherent);
32 
dma_free_coherent(struct device * hwdev,size_t size,void * vaddr,dma_addr_t dma_handle)33 void dma_free_coherent(struct device *hwdev, size_t size, void *vaddr, dma_addr_t dma_handle)
34 {
35 	consistent_free(vaddr);
36 }
37 
38 EXPORT_SYMBOL(dma_free_coherent);
39 
dma_map_single(struct device * dev,void * ptr,size_t size,enum dma_data_direction direction)40 dma_addr_t dma_map_single(struct device *dev, void *ptr, size_t size,
41 			  enum dma_data_direction direction)
42 {
43 	BUG_ON(direction == DMA_NONE);
44 
45 	frv_cache_wback_inv((unsigned long) ptr, (unsigned long) ptr + size);
46 
47 	return virt_to_bus(ptr);
48 }
49 
50 EXPORT_SYMBOL(dma_map_single);
51 
dma_map_sg(struct device * dev,struct scatterlist * sg,int nents,enum dma_data_direction direction)52 int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
53 	       enum dma_data_direction direction)
54 {
55 	unsigned long dampr2;
56 	void *vaddr;
57 	int i;
58 
59 	BUG_ON(direction == DMA_NONE);
60 
61 	dampr2 = __get_DAMPR(2);
62 
63 	for (i = 0; i < nents; i++) {
64 		vaddr = kmap_atomic_primary(sg_page(&sg[i]), __KM_CACHE);
65 
66 		frv_dcache_writeback((unsigned long) vaddr,
67 				     (unsigned long) vaddr + PAGE_SIZE);
68 
69 	}
70 
71 	kunmap_atomic_primary(vaddr, __KM_CACHE);
72 	if (dampr2) {
73 		__set_DAMPR(2, dampr2);
74 		__set_IAMPR(2, dampr2);
75 	}
76 
77 	return nents;
78 }
79 
80 EXPORT_SYMBOL(dma_map_sg);
81 
dma_map_page(struct device * dev,struct page * page,unsigned long offset,size_t size,enum dma_data_direction direction)82 dma_addr_t dma_map_page(struct device *dev, struct page *page, unsigned long offset,
83 			size_t size, enum dma_data_direction direction)
84 {
85 	BUG_ON(direction == DMA_NONE);
86 	flush_dcache_page(page);
87 	return (dma_addr_t) page_to_phys(page) + offset;
88 }
89 
90 EXPORT_SYMBOL(dma_map_page);
91