1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/sdram.c	Tue Jan 13 11:56:28 2009 +0000
     1.3 @@ -0,0 +1,65 @@
     1.4 +/**
     1.5 + * $Id$
     1.6 + *
     1.7 + * Dreamcast main SDRAM - access methods and timing controls. This is fairly
     1.8 + * directly coupled to the SH4
     1.9 + *
    1.10 + * Copyright (c) 2005 Nathan Keynes.
    1.11 + *
    1.12 + * This program is free software; you can redistribute it and/or modify
    1.13 + * it under the terms of the GNU General Public License as published by
    1.14 + * the Free Software Foundation; either version 2 of the License, or
    1.15 + * (at your option) any later version.
    1.16 + *
    1.17 + * This program is distributed in the hope that it will be useful,
    1.18 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
    1.19 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    1.20 + * GNU General Public License for more details.
    1.21 + */
    1.22 +
    1.23 +#include "lxdream.h"
    1.24 +#include "mem.h"
    1.25 +#include "dreamcast.h"
    1.26 +#include <string.h>
    1.27 +
    1.28 +
    1.29 +static int32_t FASTCALL ext_sdram_read_long( sh4addr_t addr )
    1.30 +{
    1.31 +    return *((int32_t *)(dc_main_ram + (addr&0x00FFFFFF)));
    1.32 +}
    1.33 +static int32_t FASTCALL ext_sdram_read_word( sh4addr_t addr )
    1.34 +{
    1.35 +    return SIGNEXT16(*((int16_t *)(dc_main_ram + (addr&0x00FFFFFF))));
    1.36 +}
    1.37 +static int32_t FASTCALL ext_sdram_read_byte( sh4addr_t addr )
    1.38 +{
    1.39 +    return SIGNEXT8(*((int16_t *)(dc_main_ram + (addr&0x00FFFFFF))));
    1.40 +}
    1.41 +static void FASTCALL ext_sdram_write_long( sh4addr_t addr, uint32_t val )
    1.42 +{
    1.43 +    *(uint32_t *)(dc_main_ram + (addr&0x00FFFFFF)) = val;
    1.44 +    xlat_invalidate_long(addr);
    1.45 +}
    1.46 +static void FASTCALL ext_sdram_write_word( sh4addr_t addr, uint32_t val )
    1.47 +{
    1.48 +    *(uint16_t *)(dc_main_ram + (addr&0x00FFFFFF)) = (uint16_t)val;
    1.49 +    xlat_invalidate_word(addr);
    1.50 +}
    1.51 +static void FASTCALL ext_sdram_write_byte( sh4addr_t addr, uint32_t val )
    1.52 +{
    1.53 +    *(uint8_t *)(dc_main_ram + (addr&0x00FFFFFF)) = (uint8_t)val;
    1.54 +    xlat_invalidate_word(addr);
    1.55 +}
    1.56 +static void FASTCALL ext_sdram_read_burst( unsigned char *dest, sh4addr_t addr )
    1.57 +{
    1.58 +    memcpy( dest, dc_main_ram+(addr&0x00FFFFFF), 32 );
    1.59 +}
    1.60 +static void FASTCALL ext_sdram_write_burst( sh4addr_t addr, unsigned char *src )
    1.61 +{
    1.62 +    memcpy( dc_main_ram+(addr&0x00FFFFFF), src, 32 );
    1.63 +}
    1.64 +
    1.65 +struct mem_region_fn mem_region_sdram = { ext_sdram_read_long, ext_sdram_write_long, 
    1.66 +        ext_sdram_read_word, ext_sdram_write_word, 
    1.67 +        ext_sdram_read_byte, ext_sdram_write_byte, 
    1.68 +        ext_sdram_read_burst, ext_sdram_write_burst };