// Buffering handling // (c) Copyright 2007, Grazvydas "notaz" Ignotas #include "../PicoInt.h" int PicoCDBuffers = 0; static unsigned char *cd_buffer = NULL; static int prev_lba = 0x80000000; static int hits, reads; void PicoCDBufferInit(void) { void *tmp = NULL; prev_lba = 0x80000000; hits = reads = 0; if (PicoCDBuffers <= 1) { PicoCDBuffers = 0; return; /* buffering off */ } /* try alloc'ing until we succeed */ while (PicoCDBuffers > 0) { tmp = realloc(cd_buffer, PicoCDBuffers * 2048 + 304); if (tmp != NULL) break; PicoCDBuffers >>= 1; } if (PicoCDBuffers <= 0) return; /* buffering became off */ cd_buffer = tmp; } void PicoCDBufferFree(void) { if (cd_buffer) { free(cd_buffer); cd_buffer = NULL; } if (reads) elprintf(EL_STATUS, "CD buffer hits: %i/%i (%i%%)\n", hits, reads, hits * 100 / reads); } void PicoCDBufferFlush(void) { prev_lba = 0x80000000; } /* this is was a try to fight slow SD access of GP2X */ PICO_INTERNAL void PicoCDBufferRead(void *dest, int lba) { int is_bin, offs, read_len, moved = 0; reads++; is_bin = Pico_mcd->TOC.Tracks[0].ftype == TYPE_BIN; if (PicoCDBuffers <= 0) { /* no buffering */ int where_seek = is_bin ? (lba * 2352 + 16) : (lba << 11); pm_seek(Pico_mcd->TOC.Tracks[0].F, where_seek, SEEK_SET); pm_read(dest, 2048, Pico_mcd->TOC.Tracks[0].F); return; } /* hit? */ offs = lba - prev_lba; if (offs >= 0 && offs < PicoCDBuffers) { hits++; if (offs == 0) dprintf("CD buffer seek to old %i -> %i\n", prev_lba, lba); memcpy32(dest, (int *)(cd_buffer + offs*2048), 2048/4); return; } if (prev_lba + PicoCDBuffers != lba) { int where_seek = is_bin ? (lba * 2352 + 16) : (lba << 11); dprintf("CD buffer seek %i -> %i\n", prev_lba, lba); pm_seek(Pico_mcd->TOC.Tracks[0].F, where_seek, SEEK_SET); } dprintf("CD buffer miss %i -> %i\n", prev_lba, lba); if (lba < prev_lba && prev_lba - lba < PicoCDBuffers) { read_len = prev_lba - lba; dprintf("CD buffer move=%i, read_len=%i", PicoCDBuffers - read_len, read_len); memmove(cd_buffer + read_len*2048, cd_buffer, (PicoCDBuffers - read_len)*2048); moved = 1; } else { read_len = PicoCDBuffers; } if (PicoMessage != NULL && read_len >= 512) { PicoMessage("Buffering data..."); } if (is_bin) { int i = 0; #if REDUCE_IO_CALLS int bufs = (read_len*2048) / (2048+304); pm_read(cd_buffer, bufs*(2048+304), Pico_mcd->TOC.Tracks[0].F); for (i = 1; i < bufs; i++) // should really use memmove here, but my memcpy32 implementation is also suitable here memcpy32((int *)(cd_buffer + i*2048), (int *)(cd_buffer + i*(2048+304)), 2048/4); #endif for (; i < read_len - 1; i++) { pm_read(cd_buffer + i*2048, 2048 + 304, Pico_mcd->TOC.Tracks[0].F); // pm_seek(Pico_mcd->TOC.Tracks[0].F, 304, SEEK_CUR); // seeking is slower, in PSP case even more } // further data might be moved, do not overwrite pm_read(cd_buffer + i*2048, 2048, Pico_mcd->TOC.Tracks[0].F); pm_seek(Pico_mcd->TOC.Tracks[0].F, 304, SEEK_CUR); } else { pm_read(cd_buffer, read_len*2048, Pico_mcd->TOC.Tracks[0].F); } memcpy32(dest, (int *) cd_buffer, 2048/4); prev_lba = lba; if (moved) { /* file pointer must point to the same data in file, as would-be data after our buffer */ int where_seek; lba += PicoCDBuffers; where_seek = is_bin ? (lba * 2352 + 16) : (lba << 11); pm_seek(Pico_mcd->TOC.Tracks[0].F, where_seek, SEEK_SET); } }