| .. | .. |
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| 3 | 3 | |
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| 4 | 4 | #include <linux/types.h> |
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| 5 | 5 | #include <linux/mm.h> |
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| 6 | | -#include <linux/string.h> |
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| 7 | | -#include <linux/dma-noncoherent.h> |
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| 8 | | -#include <linux/io.h> |
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| 6 | +#include <linux/dma-map-ops.h> |
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| 9 | 7 | #include <linux/cache.h> |
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| 10 | 8 | #include <linux/highmem.h> |
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| 11 | | -#include <linux/slab.h> |
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| 12 | 9 | #include <asm/cacheflush.h> |
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| 13 | 10 | #include <asm/tlbflush.h> |
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| 14 | 11 | #include <asm/proc-fns.h> |
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| 15 | | - |
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| 16 | | -/* |
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| 17 | | - * This is the page table (2MB) covering uncached, DMA consistent allocations |
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| 18 | | - */ |
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| 19 | | -static pte_t *consistent_pte; |
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| 20 | | -static DEFINE_RAW_SPINLOCK(consistent_lock); |
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| 21 | | - |
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| 22 | | -/* |
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| 23 | | - * VM region handling support. |
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| 24 | | - * |
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| 25 | | - * This should become something generic, handling VM region allocations for |
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| 26 | | - * vmalloc and similar (ioremap, module space, etc). |
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| 27 | | - * |
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| 28 | | - * I envisage vmalloc()'s supporting vm_struct becoming: |
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| 29 | | - * |
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| 30 | | - * struct vm_struct { |
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| 31 | | - * struct vm_region region; |
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| 32 | | - * unsigned long flags; |
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| 33 | | - * struct page **pages; |
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| 34 | | - * unsigned int nr_pages; |
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| 35 | | - * unsigned long phys_addr; |
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| 36 | | - * }; |
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| 37 | | - * |
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| 38 | | - * get_vm_area() would then call vm_region_alloc with an appropriate |
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| 39 | | - * struct vm_region head (eg): |
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| 40 | | - * |
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| 41 | | - * struct vm_region vmalloc_head = { |
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| 42 | | - * .vm_list = LIST_HEAD_INIT(vmalloc_head.vm_list), |
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| 43 | | - * .vm_start = VMALLOC_START, |
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| 44 | | - * .vm_end = VMALLOC_END, |
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| 45 | | - * }; |
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| 46 | | - * |
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| 47 | | - * However, vmalloc_head.vm_start is variable (typically, it is dependent on |
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| 48 | | - * the amount of RAM found at boot time.) I would imagine that get_vm_area() |
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| 49 | | - * would have to initialise this each time prior to calling vm_region_alloc(). |
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| 50 | | - */ |
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| 51 | | -struct arch_vm_region { |
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| 52 | | - struct list_head vm_list; |
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| 53 | | - unsigned long vm_start; |
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| 54 | | - unsigned long vm_end; |
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| 55 | | - struct page *vm_pages; |
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| 56 | | -}; |
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| 57 | | - |
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| 58 | | -static struct arch_vm_region consistent_head = { |
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| 59 | | - .vm_list = LIST_HEAD_INIT(consistent_head.vm_list), |
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| 60 | | - .vm_start = CONSISTENT_BASE, |
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| 61 | | - .vm_end = CONSISTENT_END, |
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| 62 | | -}; |
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| 63 | | - |
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| 64 | | -static struct arch_vm_region *vm_region_alloc(struct arch_vm_region *head, |
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| 65 | | - size_t size, int gfp) |
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| 66 | | -{ |
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| 67 | | - unsigned long addr = head->vm_start, end = head->vm_end - size; |
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| 68 | | - unsigned long flags; |
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| 69 | | - struct arch_vm_region *c, *new; |
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| 70 | | - |
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| 71 | | - new = kmalloc(sizeof(struct arch_vm_region), gfp); |
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| 72 | | - if (!new) |
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| 73 | | - goto out; |
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| 74 | | - |
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| 75 | | - raw_spin_lock_irqsave(&consistent_lock, flags); |
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| 76 | | - |
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| 77 | | - list_for_each_entry(c, &head->vm_list, vm_list) { |
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| 78 | | - if ((addr + size) < addr) |
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| 79 | | - goto nospc; |
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| 80 | | - if ((addr + size) <= c->vm_start) |
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| 81 | | - goto found; |
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| 82 | | - addr = c->vm_end; |
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| 83 | | - if (addr > end) |
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| 84 | | - goto nospc; |
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| 85 | | - } |
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| 86 | | - |
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| 87 | | -found: |
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| 88 | | - /* |
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| 89 | | - * Insert this entry _before_ the one we found. |
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| 90 | | - */ |
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| 91 | | - list_add_tail(&new->vm_list, &c->vm_list); |
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| 92 | | - new->vm_start = addr; |
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| 93 | | - new->vm_end = addr + size; |
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| 94 | | - |
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| 95 | | - raw_spin_unlock_irqrestore(&consistent_lock, flags); |
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| 96 | | - return new; |
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| 97 | | - |
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| 98 | | -nospc: |
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| 99 | | - raw_spin_unlock_irqrestore(&consistent_lock, flags); |
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| 100 | | - kfree(new); |
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| 101 | | -out: |
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| 102 | | - return NULL; |
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| 103 | | -} |
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| 104 | | - |
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| 105 | | -static struct arch_vm_region *vm_region_find(struct arch_vm_region *head, |
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| 106 | | - unsigned long addr) |
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| 107 | | -{ |
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| 108 | | - struct arch_vm_region *c; |
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| 109 | | - |
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| 110 | | - list_for_each_entry(c, &head->vm_list, vm_list) { |
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| 111 | | - if (c->vm_start == addr) |
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| 112 | | - goto out; |
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| 113 | | - } |
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| 114 | | - c = NULL; |
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| 115 | | -out: |
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| 116 | | - return c; |
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| 117 | | -} |
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| 118 | | - |
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| 119 | | -void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, |
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| 120 | | - gfp_t gfp, unsigned long attrs) |
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| 121 | | -{ |
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| 122 | | - struct page *page; |
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| 123 | | - struct arch_vm_region *c; |
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| 124 | | - unsigned long order; |
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| 125 | | - u64 mask = ~0ULL, limit; |
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| 126 | | - pgprot_t prot = pgprot_noncached(PAGE_KERNEL); |
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| 127 | | - |
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| 128 | | - if (!consistent_pte) { |
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| 129 | | - pr_err("%s: not initialized\n", __func__); |
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| 130 | | - dump_stack(); |
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| 131 | | - return NULL; |
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| 132 | | - } |
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| 133 | | - |
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| 134 | | - if (dev) { |
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| 135 | | - mask = dev->coherent_dma_mask; |
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| 136 | | - |
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| 137 | | - /* |
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| 138 | | - * Sanity check the DMA mask - it must be non-zero, and |
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| 139 | | - * must be able to be satisfied by a DMA allocation. |
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| 140 | | - */ |
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| 141 | | - if (mask == 0) { |
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| 142 | | - dev_warn(dev, "coherent DMA mask is unset\n"); |
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| 143 | | - goto no_page; |
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| 144 | | - } |
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| 145 | | - |
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| 146 | | - } |
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| 147 | | - |
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| 148 | | - /* |
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| 149 | | - * Sanity check the allocation size. |
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| 150 | | - */ |
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| 151 | | - size = PAGE_ALIGN(size); |
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| 152 | | - limit = (mask + 1) & ~mask; |
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| 153 | | - if ((limit && size >= limit) || |
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| 154 | | - size >= (CONSISTENT_END - CONSISTENT_BASE)) { |
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| 155 | | - pr_warn("coherent allocation too big " |
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| 156 | | - "(requested %#x mask %#llx)\n", size, mask); |
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| 157 | | - goto no_page; |
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| 158 | | - } |
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| 159 | | - |
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| 160 | | - order = get_order(size); |
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| 161 | | - |
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| 162 | | - if (mask != 0xffffffff) |
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| 163 | | - gfp |= GFP_DMA; |
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| 164 | | - |
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| 165 | | - page = alloc_pages(gfp, order); |
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| 166 | | - if (!page) |
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| 167 | | - goto no_page; |
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| 168 | | - |
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| 169 | | - /* |
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| 170 | | - * Invalidate any data that might be lurking in the |
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| 171 | | - * kernel direct-mapped region for device DMA. |
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| 172 | | - */ |
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| 173 | | - { |
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| 174 | | - unsigned long kaddr = (unsigned long)page_address(page); |
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| 175 | | - memset(page_address(page), 0, size); |
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| 176 | | - cpu_dma_wbinval_range(kaddr, kaddr + size); |
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| 177 | | - } |
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| 178 | | - |
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| 179 | | - /* |
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| 180 | | - * Allocate a virtual address in the consistent mapping region. |
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| 181 | | - */ |
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| 182 | | - c = vm_region_alloc(&consistent_head, size, |
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| 183 | | - gfp & ~(__GFP_DMA | __GFP_HIGHMEM)); |
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| 184 | | - if (c) { |
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| 185 | | - pte_t *pte = consistent_pte + CONSISTENT_OFFSET(c->vm_start); |
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| 186 | | - struct page *end = page + (1 << order); |
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| 187 | | - |
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| 188 | | - c->vm_pages = page; |
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| 189 | | - |
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| 190 | | - /* |
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| 191 | | - * Set the "dma handle" |
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| 192 | | - */ |
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| 193 | | - *handle = page_to_phys(page); |
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| 194 | | - |
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| 195 | | - do { |
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| 196 | | - BUG_ON(!pte_none(*pte)); |
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| 197 | | - |
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| 198 | | - /* |
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| 199 | | - * x86 does not mark the pages reserved... |
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| 200 | | - */ |
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| 201 | | - SetPageReserved(page); |
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| 202 | | - set_pte(pte, mk_pte(page, prot)); |
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| 203 | | - page++; |
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| 204 | | - pte++; |
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| 205 | | - } while (size -= PAGE_SIZE); |
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| 206 | | - |
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| 207 | | - /* |
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| 208 | | - * Free the otherwise unused pages. |
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| 209 | | - */ |
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| 210 | | - while (page < end) { |
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| 211 | | - __free_page(page); |
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| 212 | | - page++; |
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| 213 | | - } |
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| 214 | | - |
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| 215 | | - return (void *)c->vm_start; |
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| 216 | | - } |
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| 217 | | - |
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| 218 | | - if (page) |
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| 219 | | - __free_pages(page, order); |
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| 220 | | -no_page: |
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| 221 | | - *handle = ~0; |
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| 222 | | - return NULL; |
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| 223 | | -} |
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| 224 | | - |
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| 225 | | -void arch_dma_free(struct device *dev, size_t size, void *cpu_addr, |
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| 226 | | - dma_addr_t handle, unsigned long attrs) |
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| 227 | | -{ |
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| 228 | | - struct arch_vm_region *c; |
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| 229 | | - unsigned long flags, addr; |
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| 230 | | - pte_t *ptep; |
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| 231 | | - |
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| 232 | | - size = PAGE_ALIGN(size); |
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| 233 | | - |
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| 234 | | - raw_spin_lock_irqsave(&consistent_lock, flags); |
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| 235 | | - |
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| 236 | | - c = vm_region_find(&consistent_head, (unsigned long)cpu_addr); |
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| 237 | | - if (!c) |
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| 238 | | - goto no_area; |
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| 239 | | - |
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| 240 | | - if ((c->vm_end - c->vm_start) != size) { |
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| 241 | | - pr_err("%s: freeing wrong coherent size (%ld != %d)\n", |
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| 242 | | - __func__, c->vm_end - c->vm_start, size); |
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| 243 | | - dump_stack(); |
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| 244 | | - size = c->vm_end - c->vm_start; |
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| 245 | | - } |
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| 246 | | - |
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| 247 | | - ptep = consistent_pte + CONSISTENT_OFFSET(c->vm_start); |
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| 248 | | - addr = c->vm_start; |
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| 249 | | - do { |
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| 250 | | - pte_t pte = ptep_get_and_clear(&init_mm, addr, ptep); |
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| 251 | | - unsigned long pfn; |
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| 252 | | - |
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| 253 | | - ptep++; |
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| 254 | | - addr += PAGE_SIZE; |
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| 255 | | - |
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| 256 | | - if (!pte_none(pte) && pte_present(pte)) { |
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| 257 | | - pfn = pte_pfn(pte); |
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| 258 | | - |
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| 259 | | - if (pfn_valid(pfn)) { |
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| 260 | | - struct page *page = pfn_to_page(pfn); |
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| 261 | | - |
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| 262 | | - /* |
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| 263 | | - * x86 does not mark the pages reserved... |
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| 264 | | - */ |
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| 265 | | - ClearPageReserved(page); |
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| 266 | | - |
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| 267 | | - __free_page(page); |
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| 268 | | - continue; |
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| 269 | | - } |
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| 270 | | - } |
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| 271 | | - |
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| 272 | | - pr_crit("%s: bad page in kernel page table\n", __func__); |
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| 273 | | - } while (size -= PAGE_SIZE); |
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| 274 | | - |
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| 275 | | - flush_tlb_kernel_range(c->vm_start, c->vm_end); |
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| 276 | | - |
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| 277 | | - list_del(&c->vm_list); |
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| 278 | | - |
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| 279 | | - raw_spin_unlock_irqrestore(&consistent_lock, flags); |
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| 280 | | - |
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| 281 | | - kfree(c); |
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| 282 | | - return; |
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| 283 | | - |
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| 284 | | -no_area: |
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| 285 | | - raw_spin_unlock_irqrestore(&consistent_lock, flags); |
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| 286 | | - pr_err("%s: trying to free invalid coherent area: %p\n", |
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| 287 | | - __func__, cpu_addr); |
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| 288 | | - dump_stack(); |
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| 289 | | -} |
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| 290 | | - |
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| 291 | | -/* |
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| 292 | | - * Initialise the consistent memory allocation. |
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| 293 | | - */ |
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| 294 | | -static int __init consistent_init(void) |
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| 295 | | -{ |
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| 296 | | - pgd_t *pgd; |
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| 297 | | - pmd_t *pmd; |
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| 298 | | - pte_t *pte; |
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| 299 | | - int ret = 0; |
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| 300 | | - |
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| 301 | | - do { |
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| 302 | | - pgd = pgd_offset(&init_mm, CONSISTENT_BASE); |
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| 303 | | - pmd = pmd_alloc(&init_mm, pgd, CONSISTENT_BASE); |
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| 304 | | - if (!pmd) { |
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| 305 | | - pr_err("%s: no pmd tables\n", __func__); |
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| 306 | | - ret = -ENOMEM; |
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| 307 | | - break; |
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| 308 | | - } |
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| 309 | | - /* The first level mapping may be created in somewhere. |
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| 310 | | - * It's not necessary to warn here. */ |
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| 311 | | - /* WARN_ON(!pmd_none(*pmd)); */ |
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| 312 | | - |
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| 313 | | - pte = pte_alloc_kernel(pmd, CONSISTENT_BASE); |
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| 314 | | - if (!pte) { |
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| 315 | | - ret = -ENOMEM; |
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| 316 | | - break; |
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| 317 | | - } |
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| 318 | | - |
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| 319 | | - consistent_pte = pte; |
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| 320 | | - } while (0); |
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| 321 | | - |
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| 322 | | - return ret; |
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| 323 | | -} |
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| 324 | | - |
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| 325 | | -core_initcall(consistent_init); |
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| 326 | 12 | |
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| 327 | 13 | static inline void cache_op(phys_addr_t paddr, size_t size, |
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| 328 | 14 | void (*fn)(unsigned long start, unsigned long end)) |
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| .. | .. |
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| 360 | 46 | } while (left); |
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| 361 | 47 | } |
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| 362 | 48 | |
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| 363 | | -void arch_sync_dma_for_device(struct device *dev, phys_addr_t paddr, |
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| 364 | | - size_t size, enum dma_data_direction dir) |
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| 49 | +void arch_sync_dma_for_device(phys_addr_t paddr, size_t size, |
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| 50 | + enum dma_data_direction dir) |
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| 365 | 51 | { |
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| 366 | 52 | switch (dir) { |
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| 367 | 53 | case DMA_FROM_DEVICE: |
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| .. | .. |
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| 375 | 61 | } |
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| 376 | 62 | } |
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| 377 | 63 | |
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| 378 | | -void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr, |
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| 379 | | - size_t size, enum dma_data_direction dir) |
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| 64 | +void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size, |
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| 65 | + enum dma_data_direction dir) |
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| 380 | 66 | { |
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| 381 | 67 | switch (dir) { |
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| 382 | 68 | case DMA_TO_DEVICE: |
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| .. | .. |
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| 389 | 75 | BUG(); |
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| 390 | 76 | } |
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| 391 | 77 | } |
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| 78 | + |
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| 79 | +void arch_dma_prep_coherent(struct page *page, size_t size) |
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| 80 | +{ |
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| 81 | + cache_op(page_to_phys(page), size, cpu_dma_wbinval_range); |
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| 82 | +} |
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