| 1 | // Buffering handling |
| 2 | // (c) Copyright 2007, Grazvydas "notaz" Ignotas |
| 3 | |
| 4 | #include "../PicoInt.h" |
| 5 | |
| 6 | //#include <stdlib.h> |
| 7 | |
| 8 | int PicoCDBuffers = 0; |
| 9 | static unsigned char *cd_buffer = NULL; |
| 10 | static int prev_lba = 0x80000000; |
| 11 | |
| 12 | static int hits, reads; |
| 13 | |
| 14 | |
| 15 | void PicoCDBufferInit(void) |
| 16 | { |
| 17 | void *tmp; |
| 18 | |
| 19 | prev_lba = 0x80000000; |
| 20 | hits = reads = 0; |
| 21 | |
| 22 | if (PicoCDBuffers <= 1) { |
| 23 | PicoCDBuffers = 0; |
| 24 | return; /* buffering off */ |
| 25 | } |
| 26 | |
| 27 | /* try alloc'ing until we succeed */ |
| 28 | while (PicoCDBuffers > 0) |
| 29 | { |
| 30 | tmp = realloc(cd_buffer, PicoCDBuffers * 2048); |
| 31 | if (tmp != NULL) break; |
| 32 | PicoCDBuffers >>= 1; |
| 33 | } |
| 34 | |
| 35 | if (PicoCDBuffers <= 0) return; /* buffering became off */ |
| 36 | |
| 37 | cd_buffer = tmp; |
| 38 | } |
| 39 | |
| 40 | |
| 41 | void PicoCDBufferFree(void) |
| 42 | { |
| 43 | if (cd_buffer) { |
| 44 | free(cd_buffer); |
| 45 | cd_buffer = NULL; |
| 46 | } |
| 47 | if (reads) |
| 48 | printf("CD buffer hits: %i/%i (%i%%)\n", hits, reads, hits * 100 / reads); |
| 49 | } |
| 50 | |
| 51 | |
| 52 | /* this is a try to fight slow SD access of GP2X */ |
| 53 | PICO_INTERNAL void PicoCDBufferRead(void *dest, int lba) |
| 54 | { |
| 55 | int is_bin, offs, read_len, moved = 0; |
| 56 | reads++; |
| 57 | |
| 58 | is_bin = Pico_mcd->TOC.Tracks[0].ftype == TYPE_BIN; |
| 59 | |
| 60 | if (PicoCDBuffers <= 0) |
| 61 | { |
| 62 | /* no buffering */ |
| 63 | int where_seek = is_bin ? (lba * 2352 + 16) : (lba << 11); |
| 64 | pm_seek(Pico_mcd->TOC.Tracks[0].F, where_seek, SEEK_SET); |
| 65 | pm_read(dest, 2048, Pico_mcd->TOC.Tracks[0].F); |
| 66 | return; |
| 67 | } |
| 68 | |
| 69 | /* hit? */ |
| 70 | offs = lba - prev_lba; |
| 71 | if (offs >= 0 && offs < PicoCDBuffers) |
| 72 | { |
| 73 | hits++; |
| 74 | if (offs == 0) dprintf("CD buffer seek to old %i -> %i\n", prev_lba, lba); |
| 75 | memcpy32(dest, (int *)(cd_buffer + offs*2048), 2048/4); |
| 76 | return; |
| 77 | } |
| 78 | |
| 79 | if (prev_lba + PicoCDBuffers != lba) |
| 80 | { |
| 81 | int where_seek = is_bin ? (lba * 2352 + 16) : (lba << 11); |
| 82 | dprintf("CD buffer seek %i -> %i\n", prev_lba, lba); |
| 83 | pm_seek(Pico_mcd->TOC.Tracks[0].F, where_seek, SEEK_SET); |
| 84 | } |
| 85 | |
| 86 | dprintf("CD buffer miss %i -> %i\n", prev_lba, lba); |
| 87 | |
| 88 | if (lba < prev_lba && prev_lba - lba < PicoCDBuffers) |
| 89 | { |
| 90 | read_len = prev_lba - lba; |
| 91 | dprintf("CD buffer move=%i, read_len=%i", PicoCDBuffers - read_len, read_len); |
| 92 | memmove(cd_buffer + read_len*2048, cd_buffer, (PicoCDBuffers - read_len)*2048); |
| 93 | moved = 1; |
| 94 | } |
| 95 | else |
| 96 | { |
| 97 | read_len = PicoCDBuffers; |
| 98 | } |
| 99 | |
| 100 | if (PicoMessage != NULL && read_len >= 512) |
| 101 | { |
| 102 | PicoMessage("Buffering data..."); |
| 103 | } |
| 104 | |
| 105 | if (is_bin) |
| 106 | { |
| 107 | int i; |
| 108 | for (i = 0; i < read_len; i++) |
| 109 | { |
| 110 | pm_read(cd_buffer + i*2048, 2048, Pico_mcd->TOC.Tracks[0].F); |
| 111 | pm_seek(Pico_mcd->TOC.Tracks[0].F, 304, SEEK_CUR); |
| 112 | } |
| 113 | } |
| 114 | else |
| 115 | { |
| 116 | pm_read(cd_buffer, read_len*2048, Pico_mcd->TOC.Tracks[0].F); |
| 117 | } |
| 118 | memcpy32(dest, (int *) cd_buffer, 2048/4); |
| 119 | prev_lba = lba; |
| 120 | |
| 121 | if (moved) |
| 122 | { |
| 123 | /* file pointer must point to the same data in file, as would-be data after our buffer */ |
| 124 | int where_seek; |
| 125 | lba += PicoCDBuffers; |
| 126 | where_seek = is_bin ? (lba * 2352 + 16) : (lba << 11); |
| 127 | pm_seek(Pico_mcd->TOC.Tracks[0].F, where_seek, SEEK_SET); |
| 128 | } |
| 129 | } |
| 130 | |