xref: /openbmc/linux/arch/m68k/kernel/dma.c (revision be709d48)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file COPYING in the main directory of this archive
4  * for more details.
5  */
6 
7 #undef DEBUG
8 
9 #include <linux/dma-noncoherent.h>
10 #include <linux/device.h>
11 #include <linux/kernel.h>
12 #include <linux/platform_device.h>
13 #include <linux/scatterlist.h>
14 #include <linux/slab.h>
15 #include <linux/vmalloc.h>
16 #include <linux/export.h>
17 
18 #include <asm/pgalloc.h>
19 
20 #if defined(CONFIG_MMU) && !defined(CONFIG_COLDFIRE)
21 
22 void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
23 		gfp_t flag, unsigned long attrs)
24 {
25 	struct page *page, **map;
26 	pgprot_t pgprot;
27 	void *addr;
28 	int i, order;
29 
30 	pr_debug("dma_alloc_coherent: %d,%x\n", size, flag);
31 
32 	size = PAGE_ALIGN(size);
33 	order = get_order(size);
34 
35 	page = alloc_pages(flag | __GFP_ZERO, order);
36 	if (!page)
37 		return NULL;
38 
39 	*handle = page_to_phys(page);
40 	map = kmalloc(sizeof(struct page *) << order, flag & ~__GFP_DMA);
41 	if (!map) {
42 		__free_pages(page, order);
43 		return NULL;
44 	}
45 	split_page(page, order);
46 
47 	order = 1 << order;
48 	size >>= PAGE_SHIFT;
49 	map[0] = page;
50 	for (i = 1; i < size; i++)
51 		map[i] = page + i;
52 	for (; i < order; i++)
53 		__free_page(page + i);
54 	pgprot = __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY);
55 	if (CPU_IS_040_OR_060)
56 		pgprot_val(pgprot) |= _PAGE_GLOBAL040 | _PAGE_NOCACHE_S;
57 	else
58 		pgprot_val(pgprot) |= _PAGE_NOCACHE030;
59 	addr = vmap(map, size, VM_MAP, pgprot);
60 	kfree(map);
61 
62 	return addr;
63 }
64 
65 void arch_dma_free(struct device *dev, size_t size, void *addr,
66 		dma_addr_t handle, unsigned long attrs)
67 {
68 	pr_debug("dma_free_coherent: %p, %x\n", addr, handle);
69 	vfree(addr);
70 }
71 
72 #else
73 
74 #include <asm/cacheflush.h>
75 
76 void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
77 		gfp_t gfp, unsigned long attrs)
78 {
79 	void *ret;
80 
81 	if (dev == NULL || (*dev->dma_mask < 0xffffffff))
82 		gfp |= GFP_DMA;
83 	ret = (void *)__get_free_pages(gfp, get_order(size));
84 
85 	if (ret != NULL) {
86 		memset(ret, 0, size);
87 		*dma_handle = virt_to_phys(ret);
88 	}
89 	return ret;
90 }
91 
92 void arch_dma_free(struct device *dev, size_t size, void *vaddr,
93 		dma_addr_t dma_handle, unsigned long attrs)
94 {
95 	free_pages((unsigned long)vaddr, get_order(size));
96 }
97 
98 #endif /* CONFIG_MMU && !CONFIG_COLDFIRE */
99 
100 void arch_sync_dma_for_device(struct device *dev, phys_addr_t handle,
101 		size_t size, enum dma_data_direction dir)
102 {
103 	switch (dir) {
104 	case DMA_BIDIRECTIONAL:
105 	case DMA_TO_DEVICE:
106 		cache_push(handle, size);
107 		break;
108 	case DMA_FROM_DEVICE:
109 		cache_clear(handle, size);
110 		break;
111 	default:
112 		pr_err_ratelimited("dma_sync_single_for_device: unsupported dir %u\n",
113 				   dir);
114 		break;
115 	}
116 }
117 
118 void arch_setup_pdev_archdata(struct platform_device *pdev)
119 {
120 	if (pdev->dev.coherent_dma_mask == DMA_MASK_NONE &&
121 	    pdev->dev.dma_mask == NULL) {
122 		pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
123 		pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
124 	}
125 }
126