1
2
3
4
5
6
7
8
9
10
11
12
13
14#include <linux/dma-contiguous.h>
15#include <linux/dma-noncoherent.h>
16#include <linux/dma-direct.h>
17#include <linux/gfp.h>
18#include <linux/highmem.h>
19#include <linux/mm.h>
20#include <linux/types.h>
21#include <asm/cacheflush.h>
22#include <asm/io.h>
23#include <asm/platform.h>
24
25static void do_cache_op(phys_addr_t paddr, size_t size,
26 void (*fn)(unsigned long, unsigned long))
27{
28 unsigned long off = paddr & (PAGE_SIZE - 1);
29 unsigned long pfn = PFN_DOWN(paddr);
30 struct page *page = pfn_to_page(pfn);
31
32 if (!PageHighMem(page))
33 fn((unsigned long)phys_to_virt(paddr), size);
34 else
35 while (size > 0) {
36 size_t sz = min_t(size_t, size, PAGE_SIZE - off);
37 void *vaddr = kmap_atomic(page);
38
39 fn((unsigned long)vaddr + off, sz);
40 kunmap_atomic(vaddr);
41 off = 0;
42 ++page;
43 size -= sz;
44 }
45}
46
47void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr,
48 size_t size, enum dma_data_direction dir)
49{
50 switch (dir) {
51 case DMA_BIDIRECTIONAL:
52 case DMA_FROM_DEVICE:
53 do_cache_op(paddr, size, __invalidate_dcache_range);
54 break;
55
56 case DMA_NONE:
57 BUG();
58 break;
59
60 default:
61 break;
62 }
63}
64
65void arch_sync_dma_for_device(struct device *dev, phys_addr_t paddr,
66 size_t size, enum dma_data_direction dir)
67{
68 switch (dir) {
69 case DMA_BIDIRECTIONAL:
70 case DMA_TO_DEVICE:
71 if (XCHAL_DCACHE_IS_WRITEBACK)
72 do_cache_op(paddr, size, __flush_dcache_range);
73 break;
74
75 case DMA_NONE:
76 BUG();
77 break;
78
79 default:
80 break;
81 }
82}
83
84#ifdef CONFIG_MMU
85bool platform_vaddr_cached(const void *p)
86{
87 unsigned long addr = (unsigned long)p;
88
89 return addr >= XCHAL_KSEG_CACHED_VADDR &&
90 addr - XCHAL_KSEG_CACHED_VADDR < XCHAL_KSEG_SIZE;
91}
92
93bool platform_vaddr_uncached(const void *p)
94{
95 unsigned long addr = (unsigned long)p;
96
97 return addr >= XCHAL_KSEG_BYPASS_VADDR &&
98 addr - XCHAL_KSEG_BYPASS_VADDR < XCHAL_KSEG_SIZE;
99}
100
101void *platform_vaddr_to_uncached(void *p)
102{
103 return p + XCHAL_KSEG_BYPASS_VADDR - XCHAL_KSEG_CACHED_VADDR;
104}
105
106void *platform_vaddr_to_cached(void *p)
107{
108 return p + XCHAL_KSEG_CACHED_VADDR - XCHAL_KSEG_BYPASS_VADDR;
109}
110#else
111bool __attribute__((weak)) platform_vaddr_cached(const void *p)
112{
113 WARN_ONCE(1, "Default %s implementation is used\n", __func__);
114 return true;
115}
116
117bool __attribute__((weak)) platform_vaddr_uncached(const void *p)
118{
119 WARN_ONCE(1, "Default %s implementation is used\n", __func__);
120 return false;
121}
122
123void __attribute__((weak)) *platform_vaddr_to_uncached(void *p)
124{
125 WARN_ONCE(1, "Default %s implementation is used\n", __func__);
126 return p;
127}
128
129void __attribute__((weak)) *platform_vaddr_to_cached(void *p)
130{
131 WARN_ONCE(1, "Default %s implementation is used\n", __func__);
132 return p;
133}
134#endif
135
136
137
138
139
140
141void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
142 gfp_t flag, unsigned long attrs)
143{
144 unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
145 struct page *page = NULL;
146
147
148
149 flag &= ~(__GFP_DMA | __GFP_HIGHMEM);
150
151 if (dev == NULL || (dev->coherent_dma_mask < 0xffffffff))
152 flag |= GFP_DMA;
153
154 if (gfpflags_allow_blocking(flag))
155 page = dma_alloc_from_contiguous(dev, count, get_order(size),
156 flag & __GFP_NOWARN);
157
158 if (!page)
159 page = alloc_pages(flag | __GFP_ZERO, get_order(size));
160
161 if (!page)
162 return NULL;
163
164 *handle = phys_to_dma(dev, page_to_phys(page));
165
166#ifdef CONFIG_MMU
167 if (PageHighMem(page)) {
168 void *p;
169
170 p = dma_common_contiguous_remap(page, size,
171 pgprot_noncached(PAGE_KERNEL),
172 __builtin_return_address(0));
173 if (!p) {
174 if (!dma_release_from_contiguous(dev, page, count))
175 __free_pages(page, get_order(size));
176 }
177 return p;
178 }
179#endif
180 BUG_ON(!platform_vaddr_cached(page_address(page)));
181 __invalidate_dcache_range((unsigned long)page_address(page), size);
182 return platform_vaddr_to_uncached(page_address(page));
183}
184
185void arch_dma_free(struct device *dev, size_t size, void *vaddr,
186 dma_addr_t dma_handle, unsigned long attrs)
187{
188 unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
189 struct page *page;
190
191 if (platform_vaddr_uncached(vaddr)) {
192 page = virt_to_page(platform_vaddr_to_cached(vaddr));
193 } else {
194#ifdef CONFIG_MMU
195 dma_common_free_remap(vaddr, size);
196#endif
197 page = pfn_to_page(PHYS_PFN(dma_to_phys(dev, dma_handle)));
198 }
199
200 if (!dma_release_from_contiguous(dev, page, count))
201 __free_pages(page, get_order(size));
202}
203
