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/* |
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* Copyright (C) 2006-2007 Anders Gavare. All rights reserved. |
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* |
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* Redistribution and use in source and binary forms, with or without |
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* modification, are permitted provided that the following conditions are met: |
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* |
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* 1. Redistributions of source code must retain the above copyright |
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* notice, this list of conditions and the following disclaimer. |
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* 2. Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in the |
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* documentation and/or other materials provided with the distribution. |
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* 3. The name of the author may not be used to endorse or promote products |
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* derived from this software without specific prior written permission. |
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* |
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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* SUCH DAMAGE. |
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* |
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* |
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* $Id: dev_dreamcast_gdrom.c,v 1.5 2007/06/15 19:11:15 debug Exp $ |
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* |
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* COMMENT: Dreamcast GD-ROM |
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* |
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* TODO: This is just a dummy so far. |
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*/ |
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|
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#include <stdio.h> |
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#include <stdlib.h> |
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#include <string.h> |
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|
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#include "cpu.h" |
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#include "device.h" |
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#include "diskimage.h" |
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#include "machine.h" |
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#include "memory.h" |
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#include "misc.h" |
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|
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#include "dreamcast_sysasicvar.h" |
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|
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|
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/* #define debug fatal */ |
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|
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struct dreamcast_gdrom_data { |
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uint8_t busy; /* Busy status */ |
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uint8_t stat; /* Status */ |
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int cnt; /* Data length */ |
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uint8_t cond; |
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|
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int cmd_count; |
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uint8_t cmd[12]; |
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|
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uint8_t *data; |
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int data_len; |
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int cur_data_offset; |
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int cur_cnt; |
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}; |
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|
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/* Register offsets: */ |
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#define GDROM_BUSY 0x18 |
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#define GDROM_DATA 0x80 |
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#define GDROM_REGX 0x84 |
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#define GDROM_STAT 0x8c |
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#define GDROM_CNTLO 0x90 |
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#define GDROM_CNTHI 0x94 |
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#define GDROM_COND 0x9c |
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|
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#define COND_DATA_AVAIL 0x08 |
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|
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|
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static void alloc_data(struct dreamcast_gdrom_data *d) |
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{ |
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d->data_len = d->cnt; |
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|
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CHECK_ALLOCATION(d->data = malloc(d->data_len)); |
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memset(d->data, 0, d->data_len); |
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} |
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|
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|
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static void handle_command(struct cpu *cpu, struct dreamcast_gdrom_data *d) |
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{ |
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int64_t sector_nr, sector_count; |
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int i, res; |
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|
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debug("[ GDROM cmd: "); |
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for (i=0; i<12; i++) |
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debug("%02x ", d->cmd[i]); |
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debug("(cnt=%i) ]\n", d->cnt); |
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|
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if (d->data != NULL) |
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free(d->data); |
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d->data = NULL; |
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d->cur_data_offset = 0; |
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d->cur_cnt = 0; |
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|
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switch (d->cmd[0]) { |
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|
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case 0x14: |
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/* Read Table-Of-Contents: */ |
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if (d->cnt != 408) { |
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fatal("GDROM Read TOC not 408 bytes?\n"); |
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exit(1); |
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} |
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alloc_data(d); |
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|
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/* TODO: Fill TOC in a better way */ |
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d->data[99*4] = 1; /* First track */ |
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d->data[100*4] = 2; /* Last track */ |
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|
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d->data[0*4] = 0x10; /* Track 1 */ |
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d->data[1*4] = 0x10; /* Track 2 */ |
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break; |
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|
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case 0x30: |
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/* Read sectors: */ |
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if (d->cmd[1] != 0x20) { |
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fatal("GDROM unimplemented data format 0x%02x\n", |
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d->cmd[1]); |
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exit(1); |
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} |
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sector_nr = d->cmd[2] * 65536 + d->cmd[3] * 256 + d->cmd[4]; |
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sector_count = d->cmd[8] * 65536 + d->cmd[9] * 256 + d->cmd[10]; |
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if (d->cnt == 0) |
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d->cnt = 65536; |
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alloc_data(d); |
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if (sector_count * 2048 != d->data_len) { |
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fatal("Huh? GDROM data_len=0x%x, but sector_count" |
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"=0x%x\n", (int)d->data_len, (int)sector_count); |
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exit(1); |
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} |
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|
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{ |
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if (sector_nr >= 1376810) |
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sector_nr -= 1376810; |
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sector_nr -= 150; |
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if (sector_nr > 1048576) |
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sector_nr -= 1048576; |
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/* printf("sector nr = %i\n", (int)sector_nr); */ |
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|
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if (sector_nr < 1000) |
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sector_nr += (diskimage_get_baseoffset(cpu->machine, 0, DISKIMAGE_IDE) |
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/ 2048); |
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} |
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|
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res = diskimage_access(cpu->machine, 0, DISKIMAGE_IDE, |
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0, sector_nr * 2048, d->data, d->data_len); |
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if (!res) { |
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fatal("GDROM: diskimage_access failed? TODO\n"); |
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// exit(1); |
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} |
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break; |
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|
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case 0x70: |
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/* Mount: (?) */ |
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break; |
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|
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default:fatal("GDROM handle_command: unimplemented command 0x%02x" |
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"\n", d->cmd[0]); |
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exit(1); |
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} |
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|
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if (d->data != NULL) |
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d->cond |= COND_DATA_AVAIL; |
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|
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if (d->cnt == 65536) |
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d->cnt = 32768; |
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|
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SYSASIC_TRIGGER_EVENT(SYSASIC_EVENT_GDROM); |
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} |
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|
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|
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DEVICE_ACCESS(dreamcast_gdrom) |
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{ |
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struct dreamcast_gdrom_data *d = (struct dreamcast_gdrom_data *) extra; |
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uint64_t idata = 0, odata = 0; |
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|
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if (writeflag == MEM_WRITE) |
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idata = memory_readmax64(cpu, data, len); |
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|
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switch (relative_addr) { |
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|
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case GDROM_BUSY: |
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if (writeflag == MEM_READ) { |
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odata = d->busy; |
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} else { |
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fatal("Write to GDROM_BUSY?\n"); |
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exit(1); |
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} |
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break; |
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|
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case GDROM_DATA: |
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if (len != sizeof(uint16_t)) { |
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fatal("Non-16bit GDROM data access? TODO\n"); |
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exit(1); |
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} |
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|
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if (writeflag == MEM_READ) { |
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if (!(d->cond & COND_DATA_AVAIL)) { |
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fatal("Read from GDROM_DATA when no data" |
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" is available? TODO\n"); |
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exit(1); |
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} |
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if (d->cur_data_offset < d->data_len) { |
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odata = d->data[d->cur_data_offset ++]; |
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odata |= (d->data[d->cur_data_offset ++] << 8); |
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d->cur_cnt += 2; |
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if (d->cur_cnt >= d->cnt) { |
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if (d->cur_data_offset >= d->data_len) { |
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d->cond &= ~COND_DATA_AVAIL; |
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} else { |
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d->cnt = d->data_len - |
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d->cur_data_offset; |
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d->cur_cnt = 0; |
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} |
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SYSASIC_TRIGGER_EVENT( |
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SYSASIC_EVENT_GDROM); |
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} |
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} else { |
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fatal("Read too much from GDROM_DATA\n"); |
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exit(1); |
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} |
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} else { |
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if (d->busy & 0x08) { |
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if (d->cmd_count >= 12) { |
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fatal("Too much GDROM_DATA?\n"); |
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exit(1); |
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} |
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/* Add data to cmd: */ |
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d->cmd[d->cmd_count++] = idata; |
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d->cmd[d->cmd_count++] = idata >> 8; |
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if (d->cmd_count == 12) { |
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d->busy &= ~0x08; |
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handle_command(cpu, d); |
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} |
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} else { |
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fatal("Write to GDROM_DATA, but not waiting" |
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" for data?\n"); |
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exit(1); |
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} |
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} |
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break; |
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|
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case GDROM_REGX: |
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if (writeflag == MEM_READ) { |
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fatal("Read from GDROM_REGX?\n"); |
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exit(1); |
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} else { |
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/* NetBSD/dreamcast writes 0 here. */ |
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if (idata != 0) { |
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fatal("Write to GDROM_REGX?\n"); |
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exit(1); |
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} |
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} |
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break; |
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|
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case GDROM_STAT: |
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if (writeflag == MEM_READ) { |
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odata = d->stat; |
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} else { |
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fatal("Write to GDROM_STAT?\n"); |
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exit(1); |
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} |
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break; |
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|
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case GDROM_CNTLO: |
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if (writeflag == MEM_READ) { |
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odata = d->cnt & 0xff; |
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} else { |
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d->cnt = (d->cnt & 0xff00) | (idata & 0xff); |
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} |
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break; |
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|
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case GDROM_CNTHI: |
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if (writeflag == MEM_READ) { |
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odata = (d->cnt >> 8) & 0xff; |
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} else { |
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d->cnt = (d->cnt & 0x00ff) | ((idata & 0xff) << 8); |
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} |
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break; |
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|
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case GDROM_COND: |
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if (writeflag == MEM_READ) { |
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odata = d->cond; |
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} else { |
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d->cond = idata; |
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|
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/* |
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* NetBSD/dreamcast writes 0xa0 to GDROM_COND to |
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* start a command. It expects (BUSY & 0x88) to |
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* be 0x08 after writing to GDROM_COND, and STAT |
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* to be not equal to 6. NetBSD then sends 6 |
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* 16-bit data words to GDROM_DATA. |
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*/ |
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if (idata == 0xa0) { |
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d->stat = 0; /* TODO */ |
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d->busy |= 0x08; |
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d->cmd_count = 0; |
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} else { |
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fatal("dreamcast_gdrom: unimplemented " |
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"GDROM_COND = 0x%02x\n", (int)idata); |
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exit(1); |
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} |
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} |
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break; |
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|
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default:if (writeflag == MEM_READ) { |
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fatal("[ dreamcast_gdrom: read from addr 0x%x ]\n", |
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(int)relative_addr); |
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} else { |
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fatal("[ dreamcast_gdrom: write to addr 0x%x: 0x%x ]\n", |
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(int)relative_addr, (int)idata); |
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} |
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exit(1); |
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} |
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|
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if (writeflag == MEM_READ) |
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memory_writemax64(cpu, data, len, odata); |
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|
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return 1; |
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} |
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|
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|
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DEVINIT(dreamcast_gdrom) |
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{ |
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struct dreamcast_gdrom_data *d; |
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|
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CHECK_ALLOCATION(d = malloc(sizeof(struct dreamcast_gdrom_data))); |
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memset(d, 0, sizeof(struct dreamcast_gdrom_data)); |
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|
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memory_device_register(devinit->machine->memory, devinit->name, |
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0x005f7000, 0x100, dev_dreamcast_gdrom_access, d, |
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DM_DEFAULT, NULL); |
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|
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return 1; |
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} |
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