/**

 * $Id: sh4mmio.c,v 1.5 2005-12-25 05:57:00 nkeynes Exp $

 * 

 * Miscellaneous and not-really-implemented SH4 peripheral modules. Also

 * responsible for including the IMPL side of the SH4 MMIO pages.

 * Most of these will eventually be split off into their own files.

 *

 * Copyright (c) 2005 Nathan Keynes.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 */

#include "dream.h"

#include "mem.h"

#include "clock.h"

#include "sh4core.h"

#include "sh4mmio.h"

#define MMIO_IMPL

#include "sh4mmio.h"

/********************************* MMU *************************************/

MMIO_REGION_READ_STUBFN( MMU )

#define OCRAM_START (0x1C000000>>PAGE_BITS)

#define OCRAM_END   (0x20000000>>PAGE_BITS)

static char *cache = NULL;

void mmio_region_MMU_write( uint32_t reg, uint32_t val )

{

    switch(reg) {

        case CCR:

            mmu_set_cache_mode( val & (CCR_OIX|CCR_ORA) );

            INFO( "Cache mode set to %08X", val );

            break;

        default:

            break;

    }

    MMIO_WRITE( MMU, reg, val );

}

void mmu_init() 

{

    cache = mem_alloc_pages(2);

}

void mmu_set_cache_mode( int mode )

{

    uint32_t i;

    switch( mode ) {

        case MEM_OC_INDEX0: /* OIX=0 */

            for( i=OCRAM_START; i<OCRAM_END; i++ )

                page_map[i] = cache + ((i&0x02)<<(PAGE_BITS-1));

            break;

        case MEM_OC_INDEX1: /* OIX=1 */

            for( i=OCRAM_START; i<OCRAM_END; i++ )

                page_map[i] = cache + ((i&0x02000000)>>(25-PAGE_BITS));

            break;

        default: /* disabled */

            for( i=OCRAM_START; i<OCRAM_END; i++ )

                page_map[i] = NULL;

            break;

    }

}

/********************************* BSC *************************************/

uint16_t bsc_output_mask_lo = 0, bsc_output_mask_hi = 0;

uint16_t bsc_input_mask_lo = 0, bsc_input_mask_hi = 0;

uint32_t bsc_output = 0, bsc_input = 0x0300;

void bsc_out( int output, int mask )

{

    /* Go figure... The BIOS won't start without this mess though */

    if( ((output | (~mask)) & 0x03) == 3 ) {

        bsc_output |= 0x03;

    } else {

        bsc_output &= ~0x03;

    }

}

void mmio_region_BSC_write( uint32_t reg, uint32_t val )

{

    int i;

    switch( reg ) {

        case PCTRA:

            bsc_input_mask_lo = bsc_output_mask_lo = 0;

            for( i=0; i<16; i++ ) {

                int bits = (val >> (i<<1)) & 0x03;

                if( bits == 2 ) bsc_input_mask_lo |= (1<<i);

                else if( bits != 0 ) bsc_output_mask_lo |= (1<<i);

            }

            bsc_output = (bsc_output&0x000F0000) |

                (MMIO_READ( BSC, PDTRA ) & bsc_output_mask_lo);

            bsc_out( MMIO_READ( BSC, PDTRA ) | ((MMIO_READ(BSC,PDTRB)<<16)),

                     bsc_output_mask_lo | (bsc_output_mask_hi<<16) );

            break;

        case PCTRB:

            bsc_input_mask_hi = bsc_output_mask_hi = 0;

            for( i=0; i<4; i++ ) {

                int bits = (val >> (i>>1)) & 0x03;

                if( bits == 2 ) bsc_input_mask_hi |= (1<<i);

                else if( bits != 0 ) bsc_output_mask_hi |= (1<<i);

            }

            bsc_output = (bsc_output&0xFFFF) |

                ((MMIO_READ( BSC, PDTRA ) & bsc_output_mask_hi)<<16);

            break;

        case PDTRA:

            bsc_output = (bsc_output&0x000F0000) |

                (val & bsc_output_mask_lo );

            bsc_out( val | ((MMIO_READ(BSC,PDTRB)<<16)),

                     bsc_output_mask_lo | (bsc_output_mask_hi<<16) );

            break;

        case PDTRB:

            bsc_output = (bsc_output&0xFFFF) |

                ( (val & bsc_output_mask_hi)<<16 );

            break;

    }

    WARN( "Write to (mostly) unimplemented BSC (%03X <= %08X) [%s: %s]",

          reg, val, MMIO_REGID(BSC,reg), MMIO_REGDESC(BSC,reg) );

    MMIO_WRITE( BSC, reg, val );

}

int32_t mmio_region_BSC_read( uint32_t reg )

{

    int32_t val;

    switch( reg ) {

        case PDTRA:

            val = (bsc_input & bsc_input_mask_lo) | (bsc_output&0xFFFF);

            break;

        case PDTRB:

            val = ((bsc_input>>16) & bsc_input_mask_hi) | (bsc_output>>16);

            break;

        default:

            val = MMIO_READ( BSC, reg );

    }

    WARN( "Read from (mostly) unimplemented BSC (%03X => %08X) [%s: %s]",

          reg, val, MMIO_REGID(BSC,reg), MMIO_REGDESC(BSC,reg) );

    return val;

}

/********************************* UBC *************************************/

MMIO_REGION_STUBFNS( UBC )

/********************************* DMAC *************************************/

MMIO_REGION_STUBFNS( DMAC )

/********************************** SCI *************************************/

MMIO_REGION_STUBFNS( SCI )