#include "dream.h"

#include "mem.h"

#include "sh4core.h"

#include "sh4mmio.h"

#define MMIO_IMPL

#include "sh4mmio.h"

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

MMIO_REGION_READ_STUBFN( MMU )

void mmio_region_MMU_write( uint32_t reg, uint32_t val )

{

    switch(reg) {

        case CCR:

            mem_set_cache_mode( val & (CCR_OIX|CCR_ORA) );

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

            break;

        default:

            break;

    }

    MMIO_WRITE( MMU, reg, val );

}

/********************************* 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 )

/********************************* CPG *************************************/

MMIO_REGION_STUBFNS( CPG )

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

MMIO_REGION_STUBFNS( DMAC )

/********************************** RTC *************************************/

MMIO_REGION_STUBFNS( RTC )

/********************************** TMU *************************************/

int timer_divider[3] = {16,16,16};

MMIO_REGION_READ_DEFFN( TMU )

int get_timer_div( int val )

{

    switch( val & 0x07 ) {

        case 0: return 16; /* assume peripheral clock is IC/4 */

        case 1: return 64;

        case 2: return 256;

        case 3: return 1024;

        case 4: return 4096;

    }

    return 1;

}

void mmio_region_TMU_write( uint32_t reg, uint32_t val )

{

    switch( reg ) {

        case TCR0:

            timer_divider[0] = get_timer_div(val);

            break;

        case TCR1:

            timer_divider[1] = get_timer_div(val);

            break;

        case TCR2:

            timer_divider[2] = get_timer_div(val);

            break;

    }

    MMIO_WRITE( TMU, reg, val );

}

void run_timers( int cycles )

{

    int tcr = MMIO_READ( TMU, TSTR );

    cycles *= 16;

    if( tcr & 1 ) {

        int count = cycles / timer_divider[0];

        int *val = MMIO_REG( TMU, TCNT0 );

        if( *val < count ) {

            MMIO_READ( TMU, TCR0 ) |= 0x100;

            /* interrupt goes here */

            count -= *val;

            *val = MMIO_READ( TMU, TCOR0 ) - count;

        } else {

            *val -= count;

        }

    }

}

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

MMIO_REGION_STUBFNS( SCI )

/********************************* SCIF *************************************/

MMIO_REGION_STUBFNS( SCIF )