| Jason Wessel | 0fde663 | 2010-01-07 11:58:36 -0600 | [diff] [blame] | 1 | /* |
| 2 | * safe read and write memory routines callable while atomic |
| 3 | * |
| 4 | * Copyright 2005-2008 Analog Devices Inc. |
| 5 | * |
| 6 | * Licensed under the GPL-2 or later. |
| 7 | */ |
| 8 | |
| 9 | #include <linux/uaccess.h> |
| 10 | #include <asm/dma.h> |
| 11 | |
| 12 | static int validate_memory_access_address(unsigned long addr, int size) |
| 13 | { |
| 14 | if (size < 0 || addr == 0) |
| 15 | return -EFAULT; |
| 16 | return bfin_mem_access_type(addr, size); |
| 17 | } |
| 18 | |
| Steven Rostedt | f29c504 | 2011-05-19 14:35:33 -0400 | [diff] [blame] | 19 | long probe_kernel_read(void *dst, const void *src, size_t size) |
| Jason Wessel | 0fde663 | 2010-01-07 11:58:36 -0600 | [diff] [blame] | 20 | { |
| 21 | unsigned long lsrc = (unsigned long)src; |
| 22 | int mem_type; |
| 23 | |
| 24 | mem_type = validate_memory_access_address(lsrc, size); |
| 25 | if (mem_type < 0) |
| 26 | return mem_type; |
| 27 | |
| 28 | if (lsrc >= SYSMMR_BASE) { |
| 29 | if (size == 2 && lsrc % 2 == 0) { |
| 30 | u16 mmr = bfin_read16(src); |
| 31 | memcpy(dst, &mmr, sizeof(mmr)); |
| 32 | return 0; |
| 33 | } else if (size == 4 && lsrc % 4 == 0) { |
| 34 | u32 mmr = bfin_read32(src); |
| 35 | memcpy(dst, &mmr, sizeof(mmr)); |
| 36 | return 0; |
| 37 | } |
| 38 | } else { |
| 39 | switch (mem_type) { |
| 40 | case BFIN_MEM_ACCESS_CORE: |
| 41 | case BFIN_MEM_ACCESS_CORE_ONLY: |
| 42 | return __probe_kernel_read(dst, src, size); |
| 43 | /* XXX: should support IDMA here with SMP */ |
| 44 | case BFIN_MEM_ACCESS_DMA: |
| 45 | if (dma_memcpy(dst, src, size)) |
| 46 | return 0; |
| 47 | break; |
| 48 | case BFIN_MEM_ACCESS_ITEST: |
| 49 | if (isram_memcpy(dst, src, size)) |
| 50 | return 0; |
| 51 | break; |
| 52 | } |
| 53 | } |
| 54 | |
| 55 | return -EFAULT; |
| 56 | } |
| 57 | |
| Steven Rostedt | f29c504 | 2011-05-19 14:35:33 -0400 | [diff] [blame] | 58 | long probe_kernel_write(void *dst, const void *src, size_t size) |
| Jason Wessel | 0fde663 | 2010-01-07 11:58:36 -0600 | [diff] [blame] | 59 | { |
| 60 | unsigned long ldst = (unsigned long)dst; |
| 61 | int mem_type; |
| 62 | |
| 63 | mem_type = validate_memory_access_address(ldst, size); |
| 64 | if (mem_type < 0) |
| 65 | return mem_type; |
| 66 | |
| 67 | if (ldst >= SYSMMR_BASE) { |
| 68 | if (size == 2 && ldst % 2 == 0) { |
| 69 | u16 mmr; |
| 70 | memcpy(&mmr, src, sizeof(mmr)); |
| 71 | bfin_write16(dst, mmr); |
| 72 | return 0; |
| 73 | } else if (size == 4 && ldst % 4 == 0) { |
| 74 | u32 mmr; |
| 75 | memcpy(&mmr, src, sizeof(mmr)); |
| 76 | bfin_write32(dst, mmr); |
| 77 | return 0; |
| 78 | } |
| 79 | } else { |
| 80 | switch (mem_type) { |
| 81 | case BFIN_MEM_ACCESS_CORE: |
| 82 | case BFIN_MEM_ACCESS_CORE_ONLY: |
| 83 | return __probe_kernel_write(dst, src, size); |
| 84 | /* XXX: should support IDMA here with SMP */ |
| 85 | case BFIN_MEM_ACCESS_DMA: |
| 86 | if (dma_memcpy(dst, src, size)) |
| 87 | return 0; |
| 88 | break; |
| 89 | case BFIN_MEM_ACCESS_ITEST: |
| 90 | if (isram_memcpy(dst, src, size)) |
| 91 | return 0; |
| 92 | break; |
| 93 | } |
| 94 | } |
| 95 | |
| 96 | return -EFAULT; |
| 97 | } |