nkeynes@31: /**
nkeynes@255:  * $Id: asic.c,v 1.22 2006-12-21 11:12:19 nkeynes Exp $
nkeynes@31:  *
nkeynes@31:  * Support for the miscellaneous ASIC functions (Primarily event multiplexing,
nkeynes@31:  * and DMA). 
nkeynes@31:  *
nkeynes@31:  * Copyright (c) 2005 Nathan Keynes.
nkeynes@31:  *
nkeynes@31:  * This program is free software; you can redistribute it and/or modify
nkeynes@31:  * it under the terms of the GNU General Public License as published by
nkeynes@31:  * the Free Software Foundation; either version 2 of the License, or
nkeynes@31:  * (at your option) any later version.
nkeynes@31:  *
nkeynes@31:  * This program is distributed in the hope that it will be useful,
nkeynes@31:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
nkeynes@31:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
nkeynes@31:  * GNU General Public License for more details.
nkeynes@31:  */
nkeynes@35: 
nkeynes@35: #define MODULE asic_module
nkeynes@35: 
nkeynes@1: #include <assert.h>
nkeynes@137: #include <stdlib.h>
nkeynes@1: #include "dream.h"
nkeynes@1: #include "mem.h"
nkeynes@1: #include "sh4/intc.h"
nkeynes@56: #include "sh4/dmac.h"
nkeynes@2: #include "dreamcast.h"
nkeynes@25: #include "maple/maple.h"
nkeynes@25: #include "gdrom/ide.h"
nkeynes@15: #include "asic.h"
nkeynes@1: #define MMIO_IMPL
nkeynes@1: #include "asic.h"
nkeynes@1: /*
nkeynes@1:  * Open questions:
nkeynes@1:  *   1) Does changing the mask after event occurance result in the
nkeynes@1:  *      interrupt being delivered immediately?
nkeynes@1:  * TODO: Logic diagram of ASIC event/interrupt logic.
nkeynes@1:  *
nkeynes@1:  * ... don't even get me started on the "EXTDMA" page, about which, apparently,
nkeynes@1:  * practically nothing is publicly known...
nkeynes@1:  */
nkeynes@1: 
nkeynes@155: static void asic_check_cleared_events( void );
nkeynes@155: static void asic_init( void );
nkeynes@155: static void asic_reset( void );
nkeynes@155: static void asic_save_state( FILE *f );
nkeynes@155: static int asic_load_state( FILE *f );
nkeynes@155: 
nkeynes@155: struct dreamcast_module asic_module = { "ASIC", asic_init, asic_reset, NULL, NULL,
nkeynes@155: 					NULL, asic_save_state, asic_load_state };
nkeynes@15: 
nkeynes@137: #define G2_BIT5_TICKS 8
nkeynes@137: #define G2_BIT4_TICKS 16
nkeynes@137: #define G2_BIT0_ON_TICKS 24
nkeynes@137: #define G2_BIT0_OFF_TICKS 24
nkeynes@137: 
nkeynes@137: struct asic_g2_state {
nkeynes@163:     unsigned int last_update_time;
nkeynes@137:     unsigned int bit5_off_timer;
nkeynes@137:     unsigned int bit4_on_timer;
nkeynes@137:     unsigned int bit4_off_timer;
nkeynes@137:     unsigned int bit0_on_timer;
nkeynes@137:     unsigned int bit0_off_timer;
nkeynes@155: };
nkeynes@155: 
nkeynes@155: static struct asic_g2_state g2_state;
nkeynes@155: 
nkeynes@155: static void asic_init( void )
nkeynes@155: {
nkeynes@155:     register_io_region( &mmio_region_ASIC );
nkeynes@155:     register_io_region( &mmio_region_EXTDMA );
nkeynes@155:     asic_reset();
nkeynes@155: }
nkeynes@155: 
nkeynes@155: static void asic_reset( void )
nkeynes@155: {
nkeynes@155:     memset( &g2_state, 0, sizeof(g2_state) );
nkeynes@155: }    
nkeynes@155: 
nkeynes@155: static void asic_save_state( FILE *f )
nkeynes@155: {
nkeynes@155:     fwrite( &g2_state, sizeof(g2_state), 1, f );
nkeynes@155: }
nkeynes@155: 
nkeynes@155: static int asic_load_state( FILE *f )
nkeynes@155: {
nkeynes@155:     if( fread( &g2_state, sizeof(g2_state), 1, f ) != 1 )
nkeynes@155: 	return 1;
nkeynes@155:     else
nkeynes@155: 	return 0;
nkeynes@155: }
nkeynes@155: 
nkeynes@137: 
nkeynes@137: /* FIXME: Handle rollover */
nkeynes@137: void asic_g2_write_word()
nkeynes@137: {
nkeynes@163:     g2_state.last_update_time = sh4r.icount;
nkeynes@137:     g2_state.bit5_off_timer = sh4r.icount + G2_BIT5_TICKS;
nkeynes@137:     if( g2_state.bit4_off_timer < sh4r.icount )
nkeynes@137: 	g2_state.bit4_on_timer = sh4r.icount + G2_BIT5_TICKS;
nkeynes@137:     g2_state.bit4_off_timer = max(sh4r.icount,g2_state.bit4_off_timer) + G2_BIT4_TICKS;
nkeynes@137:     if( g2_state.bit0_off_timer < sh4r.icount ) {
nkeynes@137: 	g2_state.bit0_on_timer = sh4r.icount + G2_BIT0_ON_TICKS;
nkeynes@137: 	g2_state.bit0_off_timer = g2_state.bit0_on_timer + G2_BIT0_OFF_TICKS;
nkeynes@137:     } else {
nkeynes@137: 	g2_state.bit0_off_timer += G2_BIT0_OFF_TICKS;
nkeynes@137:     }
nkeynes@137:     MMIO_WRITE( ASIC, G2STATUS, MMIO_READ(ASIC, G2STATUS) | 0x20 );
nkeynes@137: }
nkeynes@137: 
nkeynes@137: static uint32_t g2_read_status()
nkeynes@137: {
nkeynes@163:     if( sh4r.icount < g2_state.last_update_time ) {
nkeynes@163: 	/* Rollover */
nkeynes@163: 	if( g2_state.last_update_time < g2_state.bit5_off_timer )
nkeynes@163: 	    g2_state.bit5_off_timer = 0;
nkeynes@163: 	if( g2_state.last_update_time < g2_state.bit4_off_timer )
nkeynes@163: 	    g2_state.bit4_off_timer = 0;
nkeynes@163: 	if( g2_state.last_update_time < g2_state.bit4_on_timer )
nkeynes@163: 	    g2_state.bit4_on_timer = 0;
nkeynes@163: 	if( g2_state.last_update_time < g2_state.bit0_off_timer )
nkeynes@163: 	    g2_state.bit0_off_timer = 0;
nkeynes@163: 	if( g2_state.last_update_time < g2_state.bit0_on_timer )
nkeynes@163: 	    g2_state.bit0_on_timer = 0;
nkeynes@163:     }
nkeynes@137:     uint32_t val = MMIO_READ( ASIC, G2STATUS );
nkeynes@137:     if( g2_state.bit5_off_timer <= sh4r.icount )
nkeynes@137: 	val = val & (~0x20);
nkeynes@163:     if( g2_state.bit4_off_timer <= sh4r.icount ||
nkeynes@163: 	(sh4r.icount + G2_BIT5_TICKS) < g2_state.bit4_off_timer )
nkeynes@137: 	val = val & (~0x10);
nkeynes@137:     else if( g2_state.bit4_on_timer <= sh4r.icount )
nkeynes@137: 	val = val | 0x10;
nkeynes@137:     if( g2_state.bit0_off_timer <= sh4r.icount )
nkeynes@137: 	val = val & (~0x01);
nkeynes@137:     else if( g2_state.bit0_on_timer <= sh4r.icount )
nkeynes@137: 	val = val | 0x01;
nkeynes@137:     return val | 0x0E;
nkeynes@137: }   
nkeynes@137: 
nkeynes@20: 
nkeynes@155: void asic_event( int event )
nkeynes@1: {
nkeynes@155:     int offset = ((event&0x60)>>3);
nkeynes@155:     int result = (MMIO_READ(ASIC, PIRQ0 + offset))  |=  (1<<(event&0x1F));
nkeynes@155: 
nkeynes@155:     if( result & MMIO_READ(ASIC, IRQA0 + offset) )
nkeynes@155:         intc_raise_interrupt( INT_IRQ13 );
nkeynes@155:     if( result & MMIO_READ(ASIC, IRQB0 + offset) )
nkeynes@155:         intc_raise_interrupt( INT_IRQ11 );
nkeynes@155:     if( result & MMIO_READ(ASIC, IRQC0 + offset) )
nkeynes@155:         intc_raise_interrupt( INT_IRQ9 );
nkeynes@1: }
nkeynes@1: 
nkeynes@155: void asic_clear_event( int event ) {
nkeynes@155:     int offset = ((event&0x60)>>3);
nkeynes@155:     uint32_t result = MMIO_READ(ASIC, PIRQ0 + offset)  & (~(1<<(event&0x1F)));
nkeynes@155:     MMIO_WRITE( ASIC, PIRQ0 + offset, result );
nkeynes@155: 
nkeynes@155:     asic_check_cleared_events();
nkeynes@155: }
nkeynes@155: 
nkeynes@155: void asic_check_cleared_events( )
nkeynes@155: {
nkeynes@155:     int i, setA = 0, setB = 0, setC = 0;
nkeynes@155:     uint32_t bits;
nkeynes@155:     for( i=0; i<3; i++ ) {
nkeynes@155: 	bits = MMIO_READ( ASIC, PIRQ0 + i );
nkeynes@155: 	setA |= (bits & MMIO_READ(ASIC, IRQA0 + i ));
nkeynes@155: 	setB |= (bits & MMIO_READ(ASIC, IRQB0 + i ));
nkeynes@155: 	setC |= (bits & MMIO_READ(ASIC, IRQC0 + i ));
nkeynes@155:     }
nkeynes@155:     if( setA == 0 )
nkeynes@155: 	intc_clear_interrupt( INT_IRQ13 );
nkeynes@155:     if( setB == 0 )
nkeynes@155: 	intc_clear_interrupt( INT_IRQ11 );
nkeynes@155:     if( setC == 0 )
nkeynes@155: 	intc_clear_interrupt( INT_IRQ9 );
nkeynes@155: }
nkeynes@155: 
nkeynes@155: 
nkeynes@155: void asic_ide_dma_transfer( )
nkeynes@155: {	
nkeynes@158:     if( MMIO_READ( EXTDMA, IDEDMACTL2 ) == 1 ) {
nkeynes@158: 	if( MMIO_READ( EXTDMA, IDEDMACTL1 ) == 1 ) {
nkeynes@158: 	    MMIO_WRITE( EXTDMA, IDEDMATXSIZ, 0 );
nkeynes@158: 	    
nkeynes@158: 	    uint32_t addr = MMIO_READ( EXTDMA, IDEDMASH4 );
nkeynes@158: 	    uint32_t length = MMIO_READ( EXTDMA, IDEDMASIZ );
nkeynes@158: 	    int dir = MMIO_READ( EXTDMA, IDEDMADIR );
nkeynes@158: 	    
nkeynes@158: 	    uint32_t xfer = ide_read_data_dma( addr, length );
nkeynes@158: 	    MMIO_WRITE( EXTDMA, IDEDMATXSIZ, xfer );
nkeynes@158: 	    MMIO_WRITE( EXTDMA, IDEDMACTL2, 0 );
nkeynes@158: 	} else { /* 0 */
nkeynes@158: 	    MMIO_WRITE( EXTDMA, IDEDMACTL2, 0 );
nkeynes@155: 	}
nkeynes@155:     }
nkeynes@155: 
nkeynes@155: }
nkeynes@155: 
nkeynes@155: 
nkeynes@1: void mmio_region_ASIC_write( uint32_t reg, uint32_t val )
nkeynes@1: {
nkeynes@1:     switch( reg ) {
nkeynes@125:     case PIRQ1:
nkeynes@125: 	val = val & 0xFFFFFFFE; /* Prevent the IDE event from clearing */
nkeynes@125: 	/* fallthrough */
nkeynes@56:     case PIRQ0:
nkeynes@56:     case PIRQ2:
nkeynes@56: 	/* Clear any interrupts */
nkeynes@56: 	MMIO_WRITE( ASIC, reg, MMIO_READ(ASIC, reg)&~val );
nkeynes@56: 	asic_check_cleared_events();
nkeynes@56: 	break;
nkeynes@244:     case SYSRESET:
nkeynes@244: 	if( val == 0x7611 ) {
nkeynes@244: 	    dreamcast_reset();
nkeynes@255: 	    sh4r.new_pc = sh4r.pc;
nkeynes@244: 	} else {
nkeynes@244: 	    WARN( "Unknown value %08X written to SYSRESET port", val );
nkeynes@244: 	}
nkeynes@244: 	break;
nkeynes@56:     case MAPLE_STATE:
nkeynes@56: 	MMIO_WRITE( ASIC, reg, val );
nkeynes@56: 	if( val & 1 ) {
nkeynes@56: 	    uint32_t maple_addr = MMIO_READ( ASIC, MAPLE_DMA) &0x1FFFFFE0;
nkeynes@56: 	    maple_handle_buffer( maple_addr );
nkeynes@56: 	    MMIO_WRITE( ASIC, reg, 0 );
nkeynes@56: 	}
nkeynes@56: 	break;
nkeynes@56:     case PVRDMACTL: /* Initiate PVR DMA transfer */
nkeynes@94: 	MMIO_WRITE( ASIC, reg, val );
nkeynes@56: 	if( val & 1 ) {
nkeynes@56: 	    uint32_t dest_addr = MMIO_READ( ASIC, PVRDMADEST) &0x1FFFFFE0;
nkeynes@56: 	    uint32_t count = MMIO_READ( ASIC, PVRDMACNT );
nkeynes@56: 	    char *data = alloca( count );
nkeynes@56: 	    uint32_t rcount = DMAC_get_buffer( 2, data, count );
nkeynes@56: 	    if( rcount != count )
nkeynes@56: 		WARN( "PVR received %08X bytes from DMA, expected %08X", rcount, count );
nkeynes@100: 	    mem_copy_to_sh4( dest_addr, data, rcount );
nkeynes@56: 	    asic_event( EVENT_PVR_DMA );
nkeynes@186: 	    MMIO_WRITE( ASIC, PVRDMACTL, 0 );
nkeynes@186: 	    MMIO_WRITE( ASIC, PVRDMACNT, 0 );
nkeynes@56: 	}
nkeynes@56: 	break;
nkeynes@158:     case PVRDMADEST: case PVRDMACNT: case MAPLE_DMA:
nkeynes@158: 	MMIO_WRITE( ASIC, reg, val );
nkeynes@158: 	break;
nkeynes@56:     default:
nkeynes@56: 	MMIO_WRITE( ASIC, reg, val );
nkeynes@1:     }
nkeynes@1: }
nkeynes@1: 
nkeynes@1: int32_t mmio_region_ASIC_read( uint32_t reg )
nkeynes@1: {
nkeynes@1:     int32_t val;
nkeynes@1:     switch( reg ) {
nkeynes@2:         /*
nkeynes@2:         case 0x89C:
nkeynes@2:             sh4_stop();
nkeynes@2:             return 0x000000B;
nkeynes@2:         */     
nkeynes@94:     case PIRQ0:
nkeynes@94:     case PIRQ1:
nkeynes@94:     case PIRQ2:
nkeynes@94:     case IRQA0:
nkeynes@94:     case IRQA1:
nkeynes@94:     case IRQA2:
nkeynes@94:     case IRQB0:
nkeynes@94:     case IRQB1:
nkeynes@94:     case IRQB2:
nkeynes@94:     case IRQC0:
nkeynes@94:     case IRQC1:
nkeynes@94:     case IRQC2:
nkeynes@158:     case MAPLE_STATE:
nkeynes@94: 	val = MMIO_READ(ASIC, reg);
nkeynes@94: 	return val;            
nkeynes@94:     case G2STATUS:
nkeynes@137: 	return g2_read_status();
nkeynes@94:     default:
nkeynes@94: 	val = MMIO_READ(ASIC, reg);
nkeynes@94: 	return val;
nkeynes@1:     }
nkeynes@94:     
nkeynes@1: }
nkeynes@1: 
nkeynes@1: MMIO_REGION_WRITE_FN( EXTDMA, reg, val )
nkeynes@1: {
nkeynes@244:     if( !idereg.interface_enabled && IS_IDE_REGISTER(reg) ) {
nkeynes@244: 	return; /* disabled */
nkeynes@244:     }
nkeynes@244: 
nkeynes@2:     switch( reg ) {
nkeynes@125:     case IDEALTSTATUS: /* Device control */
nkeynes@125: 	ide_write_control( val );
nkeynes@125: 	break;
nkeynes@125:     case IDEDATA:
nkeynes@125: 	ide_write_data_pio( val );
nkeynes@125: 	break;
nkeynes@125:     case IDEFEAT:
nkeynes@125: 	if( ide_can_write_regs() )
nkeynes@125: 	    idereg.feature = (uint8_t)val;
nkeynes@125: 	break;
nkeynes@125:     case IDECOUNT:
nkeynes@125: 	if( ide_can_write_regs() )
nkeynes@125: 	    idereg.count = (uint8_t)val;
nkeynes@125: 	break;
nkeynes@125:     case IDELBA0:
nkeynes@125: 	if( ide_can_write_regs() )
nkeynes@125: 	    idereg.lba0 = (uint8_t)val;
nkeynes@125: 	break;
nkeynes@125:     case IDELBA1:
nkeynes@125: 	if( ide_can_write_regs() )
nkeynes@125: 	    idereg.lba1 = (uint8_t)val;
nkeynes@125: 	break;
nkeynes@125:     case IDELBA2:
nkeynes@125: 	if( ide_can_write_regs() )
nkeynes@125: 	    idereg.lba2 = (uint8_t)val;
nkeynes@125: 	break;
nkeynes@125:     case IDEDEV:
nkeynes@125: 	if( ide_can_write_regs() )
nkeynes@125: 	    idereg.device = (uint8_t)val;
nkeynes@125: 	break;
nkeynes@125:     case IDECMD:
nkeynes@240: 	if( ide_can_write_regs() || val == IDE_CMD_NOP ) {
nkeynes@125: 	    ide_write_command( (uint8_t)val );
nkeynes@125: 	}
nkeynes@125: 	break;
nkeynes@125:     case IDEDMACTL1:
nkeynes@155: 	MMIO_WRITE( EXTDMA, reg, val );
nkeynes@125:     case IDEDMACTL2:
nkeynes@125: 	MMIO_WRITE( EXTDMA, reg, val );
nkeynes@155: 	asic_ide_dma_transfer( );
nkeynes@125: 	break;
nkeynes@244:     case IDEACTIVATE:
nkeynes@244: 	if( val == 0x001FFFFF ) {
nkeynes@244: 	    idereg.interface_enabled = TRUE;
nkeynes@244: 	    /* Conventional wisdom says that this is necessary but not
nkeynes@244: 	     * sufficient to enable the IDE interface.
nkeynes@244: 	     */
nkeynes@244: 	} else if( val == 0x000042FE ) {
nkeynes@244: 	    idereg.interface_enabled = FALSE;
nkeynes@244: 	}
nkeynes@125:     default:
nkeynes@2:             MMIO_WRITE( EXTDMA, reg, val );
nkeynes@2:     }
nkeynes@1: }
nkeynes@1: 
nkeynes@1: MMIO_REGION_READ_FN( EXTDMA, reg )
nkeynes@1: {
nkeynes@56:     uint32_t val;
nkeynes@244:     if( !idereg.interface_enabled && IS_IDE_REGISTER(reg) ) {
nkeynes@244: 	return 0xFFFFFFFF; /* disabled */
nkeynes@244:     }
nkeynes@244: 
nkeynes@1:     switch( reg ) {
nkeynes@158:     case IDEALTSTATUS: 
nkeynes@158: 	val = idereg.status;
nkeynes@158: 	return val;
nkeynes@158:     case IDEDATA: return ide_read_data_pio( );
nkeynes@158:     case IDEFEAT: return idereg.error;
nkeynes@158:     case IDECOUNT:return idereg.count;
nkeynes@158:     case IDELBA0: return idereg.disc;
nkeynes@158:     case IDELBA1: return idereg.lba1;
nkeynes@158:     case IDELBA2: return idereg.lba2;
nkeynes@158:     case IDEDEV: return idereg.device;
nkeynes@158:     case IDECMD:
nkeynes@158: 	val = ide_read_status();
nkeynes@158: 	return val;
nkeynes@158:     default:
nkeynes@158: 	val = MMIO_READ( EXTDMA, reg );
nkeynes@158: 	return val;
nkeynes@1:     }
nkeynes@1: }
nkeynes@1: