1 | /* |
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2 | * MC68360 buffer descriptor allocation routines |
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3 | * |
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4 | * W. Eric Norum |
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5 | * Saskatchewan Accelerator Laboratory |
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6 | * University of Saskatchewan |
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7 | * Saskatoon, Saskatchewan, CANADA |
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8 | * eric@skatter.usask.ca |
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9 | */ |
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10 | |
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11 | #include <rtems.h> |
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12 | #include <bsp.h> |
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13 | #include <rtems/m68k/m68360.h> |
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14 | #include <rtems/error.h> |
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15 | |
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16 | /* |
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17 | * Allocation order: |
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18 | * - Dual-Port RAM section 1 |
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19 | * - Dual-Port RAM section 3 |
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20 | * - Dual-Port RAM section 0 |
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21 | * - Dual-Port RAM section 2 |
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22 | */ |
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23 | static struct { |
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24 | uint8_t *base; |
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25 | uint32_t size; |
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26 | uint32_t used; |
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27 | } bdregions[] = { |
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28 | { (uint8_t *)&m360.dpram1[0], sizeof m360.dpram1, 0 }, |
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29 | { (uint8_t *)&m360.dpram3[0], sizeof m360.dpram3, 0 }, |
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30 | { (uint8_t *)&m360.dpram0[0], sizeof m360.dpram0, 0 }, |
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31 | { (uint8_t *)&m360.dpram2[0], sizeof m360.dpram2, 0 }, |
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32 | }; |
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33 | |
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34 | /* |
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35 | * Send a command to the CPM RISC processer |
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36 | */ |
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37 | void * |
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38 | M360AllocateBufferDescriptors (int count) |
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39 | { |
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40 | unsigned int i; |
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41 | ISR_Level level; |
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42 | void *bdp = NULL; |
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43 | unsigned int want = count * sizeof(m360BufferDescriptor_t); |
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44 | |
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45 | /* |
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46 | * Running with interrupts disabled is usually considered bad |
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47 | * form, but this routine is probably being run as part of an |
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48 | * initialization sequence so the effect shouldn't be too severe. |
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49 | */ |
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50 | _ISR_Local_disable (level); |
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51 | for (i = 0 ; i < sizeof(bdregions) / sizeof(bdregions[0]) ; i++) { |
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52 | /* |
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53 | * Verify that the region exists. |
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54 | * This test is necessary since some chips have |
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55 | * less dual-port RAM. |
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56 | */ |
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57 | if (bdregions[i].used == 0) { |
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58 | volatile uint8_t *cp = bdregions[i].base; |
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59 | *cp = 0xAA; |
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60 | if (*cp != 0xAA) { |
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61 | bdregions[i].used = bdregions[i].size; |
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62 | continue; |
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63 | } |
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64 | *cp = 0x55; |
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65 | if (*cp != 0x55) { |
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66 | bdregions[i].used = bdregions[i].size; |
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67 | continue; |
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68 | } |
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69 | *cp = 0x0; |
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70 | } |
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71 | if (bdregions[i].size - bdregions[i].used >= want) { |
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72 | bdp = bdregions[i].base + bdregions[i].used; |
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73 | bdregions[i].used += want; |
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74 | break; |
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75 | } |
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76 | } |
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77 | _ISR_Local_enable (level); |
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78 | if (bdp == NULL) |
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79 | rtems_panic ("Can't allocate %d buffer descriptor(s).\n", count); |
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80 | return bdp; |
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81 | } |
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82 | |
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83 | void * |
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84 | M360AllocateRiscTimers (int count) |
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85 | { |
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86 | /* |
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87 | * Convert the count to the number of buffer descriptors |
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88 | * of equal or larger size. This ensures that all buffer |
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89 | * descriptors are allocated with appropriate alignment. |
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90 | */ |
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91 | return M360AllocateBufferDescriptors (((count * 4) + |
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92 | sizeof(m360BufferDescriptor_t) - 1) / |
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93 | sizeof(m360BufferDescriptor_t)); |
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94 | } |
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