4 * Support for the miscellaneous ASIC functions (Primarily event multiplexing,
7 * Copyright (c) 2005 Nathan Keynes.
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
20 #define MODULE asic_module
30 #include "dreamcast.h"
31 #include "maple/maple.h"
32 #include "gdrom/ide.h"
33 #include "pvr2/pvr2.h"
39 * 1) Does changing the mask after event occurance result in the
40 * interrupt being delivered immediately?
41 * TODO: Logic diagram of ASIC event/interrupt logic.
43 * ... don't even get me started on the "EXTDMA" page, about which, apparently,
44 * practically nothing is publicly known...
47 static void asic_check_cleared_events( void );
48 static void asic_init( void );
49 static void asic_reset( void );
50 static uint32_t asic_run_slice( uint32_t nanosecs );
51 static void asic_save_state( FILE *f );
52 static int asic_load_state( FILE *f );
53 static uint32_t g2_update_fifo_status( uint32_t slice_cycle );
55 struct dreamcast_module asic_module = { "ASIC", asic_init, asic_reset, NULL, asic_run_slice,
56 NULL, asic_save_state, asic_load_state };
58 #define G2_BIT5_TICKS 60
59 #define G2_BIT4_TICKS 160
60 #define G2_BIT0_ON_TICKS 120
61 #define G2_BIT0_OFF_TICKS 420
63 struct asic_g2_state {
71 static struct asic_g2_state g2_state;
73 static uint32_t asic_run_slice( uint32_t nanosecs )
75 g2_update_fifo_status(nanosecs);
76 if( g2_state.bit5_off_timer <= (int32_t)nanosecs ) {
77 g2_state.bit5_off_timer = -1;
79 g2_state.bit5_off_timer -= nanosecs;
82 if( g2_state.bit4_off_timer <= (int32_t)nanosecs ) {
83 g2_state.bit4_off_timer = -1;
85 g2_state.bit4_off_timer -= nanosecs;
87 if( g2_state.bit4_on_timer <= (int32_t)nanosecs ) {
88 g2_state.bit4_on_timer = -1;
90 g2_state.bit4_on_timer -= nanosecs;
93 if( g2_state.bit0_off_timer <= (int32_t)nanosecs ) {
94 g2_state.bit0_off_timer = -1;
96 g2_state.bit0_off_timer -= nanosecs;
98 if( g2_state.bit0_on_timer <= (int32_t)nanosecs ) {
99 g2_state.bit0_on_timer = -1;
101 g2_state.bit0_on_timer -= nanosecs;
107 static void asic_init( void )
109 register_io_region( &mmio_region_ASIC );
110 register_io_region( &mmio_region_EXTDMA );
114 static void asic_reset( void )
116 memset( &g2_state, 0xFF, sizeof(g2_state) );
119 static void asic_save_state( FILE *f )
121 fwrite( &g2_state, sizeof(g2_state), 1, f );
124 static int asic_load_state( FILE *f )
126 if( fread( &g2_state, sizeof(g2_state), 1, f ) != 1 )
134 * Setup the timers for the 3 FIFO status bits following a write through the G2
135 * bus from the SH4 side. The timing is roughly as follows: (times are
136 * approximate based on software readings - I wouldn't take this as gospel but
137 * it seems to be enough to fool most programs).
138 * 0ns: Bit 5 (Input fifo?) goes high immediately on the write
139 * 40ns: Bit 5 goes low and bit 4 goes high
140 * 120ns: Bit 4 goes low, bit 0 goes high
141 * 240ns: Bit 0 goes low.
143 * Additional writes while the FIFO is in operation extend the time that the
144 * bits remain high as one might expect, without altering the time at which
145 * they initially go high.
147 void asic_g2_write_word()
149 if( g2_state.bit5_off_timer < (int32_t)sh4r.slice_cycle ) {
150 g2_state.bit5_off_timer = sh4r.slice_cycle + G2_BIT5_TICKS;
152 g2_state.bit5_off_timer += G2_BIT5_TICKS;
155 if( g2_state.bit4_on_timer < (int32_t)sh4r.slice_cycle ) {
156 g2_state.bit4_on_timer = sh4r.slice_cycle + G2_BIT5_TICKS;
159 if( g2_state.bit4_off_timer < (int32_t)sh4r.slice_cycle ) {
160 g2_state.bit4_off_timer = g2_state.bit4_on_timer + G2_BIT4_TICKS;
162 g2_state.bit4_off_timer += G2_BIT4_TICKS;
165 if( g2_state.bit0_on_timer < (int32_t)sh4r.slice_cycle ) {
166 g2_state.bit0_on_timer = sh4r.slice_cycle + G2_BIT0_ON_TICKS;
169 if( g2_state.bit0_off_timer < (int32_t)sh4r.slice_cycle ) {
170 g2_state.bit0_off_timer = g2_state.bit0_on_timer + G2_BIT0_OFF_TICKS;
172 g2_state.bit0_off_timer += G2_BIT0_OFF_TICKS;
175 MMIO_WRITE( ASIC, G2STATUS, MMIO_READ(ASIC, G2STATUS) | 0x20 );
178 static uint32_t g2_update_fifo_status( uint32_t nanos )
180 uint32_t val = MMIO_READ( ASIC, G2STATUS );
181 if( ((uint32_t)g2_state.bit5_off_timer) <= nanos ) {
183 g2_state.bit5_off_timer = -1;
185 if( ((uint32_t)g2_state.bit4_on_timer) <= nanos ) {
187 g2_state.bit4_on_timer = -1;
189 if( ((uint32_t)g2_state.bit4_off_timer) <= nanos ) {
191 g2_state.bit4_off_timer = -1;
194 if( ((uint32_t)g2_state.bit0_on_timer) <= nanos ) {
196 g2_state.bit0_on_timer = -1;
198 if( ((uint32_t)g2_state.bit0_off_timer) <= nanos ) {
200 g2_state.bit0_off_timer = -1;
203 MMIO_WRITE( ASIC, G2STATUS, val );
207 static int g2_read_status() {
208 return g2_update_fifo_status( sh4r.slice_cycle );
212 void asic_event( int event )
214 int offset = ((event&0x60)>>3);
215 int result = (MMIO_READ(ASIC, PIRQ0 + offset)) |= (1<<(event&0x1F));
217 if( result & MMIO_READ(ASIC, IRQA0 + offset) )
218 intc_raise_interrupt( INT_IRQ13 );
219 if( result & MMIO_READ(ASIC, IRQB0 + offset) )
220 intc_raise_interrupt( INT_IRQ11 );
221 if( result & MMIO_READ(ASIC, IRQC0 + offset) )
222 intc_raise_interrupt( INT_IRQ9 );
224 if( event >= 64 ) { /* Third word */
225 asic_event( EVENT_CASCADE2 );
226 } else if( event >= 32 ) { /* Second word */
227 asic_event( EVENT_CASCADE1 );
231 void asic_clear_event( int event ) {
232 int offset = ((event&0x60)>>3);
233 uint32_t result = MMIO_READ(ASIC, PIRQ0 + offset) & (~(1<<(event&0x1F)));
234 MMIO_WRITE( ASIC, PIRQ0 + offset, result );
236 /* clear cascades if necessary */
238 MMIO_WRITE( ASIC, PIRQ0, MMIO_READ( ASIC, PIRQ0 ) & 0x7FFFFFFF );
239 } else if( event >= 32 ) {
240 MMIO_WRITE( ASIC, PIRQ0, MMIO_READ( ASIC, PIRQ0 ) & 0xBFFFFFFF );
244 asic_check_cleared_events();
247 void asic_check_cleared_events( )
249 int i, setA = 0, setB = 0, setC = 0;
251 for( i=0; i<12; i+=4 ) {
252 bits = MMIO_READ( ASIC, PIRQ0 + i );
253 setA |= (bits & MMIO_READ(ASIC, IRQA0 + i ));
254 setB |= (bits & MMIO_READ(ASIC, IRQB0 + i ));
255 setC |= (bits & MMIO_READ(ASIC, IRQC0 + i ));
258 intc_clear_interrupt( INT_IRQ13 );
260 intc_clear_interrupt( INT_IRQ11 );
262 intc_clear_interrupt( INT_IRQ9 );
265 void asic_event_mask_changed( )
267 int i, setA = 0, setB = 0, setC = 0;
269 for( i=0; i<12; i+=4 ) {
270 bits = MMIO_READ( ASIC, PIRQ0 + i );
271 setA |= (bits & MMIO_READ(ASIC, IRQA0 + i ));
272 setB |= (bits & MMIO_READ(ASIC, IRQB0 + i ));
273 setC |= (bits & MMIO_READ(ASIC, IRQC0 + i ));
276 intc_clear_interrupt( INT_IRQ13 );
278 intc_raise_interrupt( INT_IRQ13 );
280 intc_clear_interrupt( INT_IRQ11 );
282 intc_raise_interrupt( INT_IRQ11 );
284 intc_clear_interrupt( INT_IRQ9 );
286 intc_raise_interrupt( INT_IRQ9 );
289 void g2_dma_transfer( int channel )
291 uint32_t offset = channel << 5;
293 if( MMIO_READ( EXTDMA, G2DMA0CTL1 + offset ) == 1 ) {
294 if( MMIO_READ( EXTDMA, G2DMA0CTL2 + offset ) == 1 ) {
295 uint32_t extaddr = MMIO_READ( EXTDMA, G2DMA0EXT + offset );
296 uint32_t sh4addr = MMIO_READ( EXTDMA, G2DMA0SH4 + offset );
297 uint32_t length = MMIO_READ( EXTDMA, G2DMA0SIZ + offset ) & 0x1FFFFFFF;
298 uint32_t dir = MMIO_READ( EXTDMA, G2DMA0DIR + offset );
299 // uint32_t mode = MMIO_READ( EXTDMA, G2DMA0MOD + offset );
300 unsigned char buf[length];
301 if( dir == 0 ) { /* SH4 to device */
302 mem_copy_from_sh4( buf, sh4addr, length );
303 mem_copy_to_sh4( extaddr, buf, length );
304 } else { /* Device to SH4 */
305 mem_copy_from_sh4( buf, extaddr, length );
306 mem_copy_to_sh4( sh4addr, buf, length );
308 MMIO_WRITE( EXTDMA, G2DMA0CTL2 + offset, 0 );
309 asic_event( EVENT_G2_DMA0 + channel );
311 MMIO_WRITE( EXTDMA, G2DMA0CTL2 + offset, 0 );
316 void asic_ide_dma_transfer( )
318 if( MMIO_READ( EXTDMA, IDEDMACTL2 ) == 1 ) {
319 if( MMIO_READ( EXTDMA, IDEDMACTL1 ) == 1 ) {
320 MMIO_WRITE( EXTDMA, IDEDMATXSIZ, 0 );
322 uint32_t addr = MMIO_READ( EXTDMA, IDEDMASH4 );
323 uint32_t length = MMIO_READ( EXTDMA, IDEDMASIZ );
324 // int dir = MMIO_READ( EXTDMA, IDEDMADIR );
326 uint32_t xfer = ide_read_data_dma( addr, length );
327 MMIO_WRITE( EXTDMA, IDEDMATXSIZ, xfer );
328 MMIO_WRITE( EXTDMA, IDEDMACTL2, 0 );
329 asic_event( EVENT_IDE_DMA );
331 MMIO_WRITE( EXTDMA, IDEDMACTL2, 0 );
336 void pvr_dma_transfer( )
338 sh4addr_t destaddr = MMIO_READ( ASIC, PVRDMADEST) &0x1FFFFFE0;
339 uint32_t count = MMIO_READ( ASIC, PVRDMACNT );
340 unsigned char *data = alloca( count );
341 uint32_t rcount = DMAC_get_buffer( 2, data, count );
342 if( rcount != count )
343 WARN( "PVR received %08X bytes from DMA, expected %08X", rcount, count );
345 pvr2_dma_write( destaddr, data, rcount );
347 MMIO_WRITE( ASIC, PVRDMACTL, 0 );
348 MMIO_WRITE( ASIC, PVRDMACNT, 0 );
349 if( destaddr & 0x01000000 ) { /* Write to texture RAM */
350 MMIO_WRITE( ASIC, PVRDMADEST, destaddr + rcount );
352 asic_event( EVENT_PVR_DMA );
355 void pvr_dma2_transfer()
357 if( MMIO_READ( EXTDMA, PVRDMA2CTL2 ) == 1 ) {
358 if( MMIO_READ( EXTDMA, PVRDMA2CTL1 ) == 1 ) {
359 sh4addr_t extaddr = MMIO_READ( EXTDMA, PVRDMA2EXT );
360 sh4addr_t sh4addr = MMIO_READ( EXTDMA, PVRDMA2SH4 );
361 int dir = MMIO_READ( EXTDMA, PVRDMA2DIR );
362 uint32_t length = MMIO_READ( EXTDMA, PVRDMA2SIZ );
363 unsigned char buf[length];
364 if( dir == 0 ) { /* SH4 to PVR */
365 mem_copy_from_sh4( buf, sh4addr, length );
366 mem_copy_to_sh4( extaddr, buf, length );
367 } else { /* PVR to SH4 */
368 mem_copy_from_sh4( buf, extaddr, length );
369 mem_copy_to_sh4( sh4addr, buf, length );
371 MMIO_WRITE( EXTDMA, PVRDMA2CTL2, 0 );
372 asic_event( EVENT_PVR_DMA2 );
377 void sort_dma_transfer( )
379 sh4addr_t table_addr = MMIO_READ( ASIC, SORTDMATBL );
380 sh4addr_t data_addr = MMIO_READ( ASIC, SORTDMADATA );
381 int table_size = MMIO_READ( ASIC, SORTDMATSIZ );
382 int addr_shift = MMIO_READ( ASIC, SORTDMAASIZ ) ? 5 : 0;
385 uint32_t *table32 = (uint32_t *)mem_get_region( table_addr );
386 uint16_t *table16 = (uint16_t *)table32;
387 uint32_t next = table_size ? (*table32++) : (uint32_t)(*table16++);
391 next = table_size ? (*table32++) : (uint32_t)(*table16++);
394 } else if( next == 2 ) {
395 asic_event( EVENT_SORT_DMA );
398 uint32_t *data = (uint32_t *)mem_get_region(data_addr + (next<<addr_shift));
403 uint32_t *poly = pvr2_ta_find_polygon_context(data, 128);
405 asic_event( EVENT_SORT_DMA_ERR );
408 uint32_t size = poly[6] & 0xFF;
413 pvr2_ta_write( (unsigned char *)data, size<<5 );
416 MMIO_WRITE( ASIC, SORTDMACNT, count );
417 MMIO_WRITE( ASIC, SORTDMACTL, 0 );
420 void maple_set_dma_state( uint32_t val )
422 gboolean in_transfer = MMIO_READ( ASIC, MAPLE_STATE ) & 1;
423 gboolean transfer_requested = val & 1;
424 if( !in_transfer && transfer_requested ) {
425 /* Initiate new DMA transfer */
426 uint32_t maple_addr = MMIO_READ( ASIC, MAPLE_DMA) &0x1FFFFFE0;
427 maple_handle_buffer( maple_addr );
429 else if ( in_transfer && !transfer_requested ) {
430 /* Cancel current DMA transfer */
431 event_cancel( EVENT_MAPLE_DMA );
433 MMIO_WRITE( ASIC, MAPLE_STATE, val );
436 gboolean asic_enable_ide_interface( gboolean enable )
438 gboolean oldval = idereg.interface_enabled;
439 idereg.interface_enabled = enable;
443 MMIO_REGION_READ_FN( ASIC, reg )
461 val = MMIO_READ(ASIC, reg);
464 return g2_read_status();
466 val = MMIO_READ(ASIC, reg);
472 MMIO_REGION_READ_DEFSUBFNS(ASIC)
474 MMIO_REGION_WRITE_FN( ASIC, reg, val )
479 break; /* Treat this as read-only for the moment */
481 val = val & 0x3FFFFFFF; /* Top two bits aren't clearable */
482 MMIO_WRITE( ASIC, reg, MMIO_READ(ASIC, reg)&~val );
483 asic_check_cleared_events();
486 /* Clear any events */
487 val = MMIO_READ(ASIC, reg)&(~val);
488 MMIO_WRITE( ASIC, reg, val );
489 if( val == 0 ) { /* all clear - clear the cascade bit */
490 MMIO_WRITE( ASIC, PIRQ0, MMIO_READ( ASIC, PIRQ0 ) & 0x7FFFFFFF );
492 asic_check_cleared_events();
503 MMIO_WRITE( ASIC, reg, val );
504 asic_event_mask_changed();
507 if( val == 0x7611 ) {
510 WARN( "Unknown value %08X written to SYSRESET port", val );
514 maple_set_dma_state( val );
517 MMIO_WRITE( ASIC, reg, (val & 0x03FFFFE0) | 0x10000000 );
520 MMIO_WRITE( ASIC, reg, val & 0x00FFFFE0 );
522 case PVRDMACTL: /* Initiate PVR DMA transfer */
524 MMIO_WRITE( ASIC, reg, val );
529 case SORTDMATBL: case SORTDMADATA:
530 MMIO_WRITE( ASIC, reg, (val & 0x0FFFFFE0) | 0x08000000 );
532 case SORTDMATSIZ: case SORTDMAASIZ:
533 MMIO_WRITE( ASIC, reg, (val & 1) );
537 MMIO_WRITE( ASIC, reg, val );
543 MMIO_WRITE( ASIC, reg, val );
546 MMIO_WRITE( ASIC, reg, val );
550 MMIO_REGION_READ_FN( EXTDMA, reg )
554 if( !idereg.interface_enabled && IS_IDE_REGISTER(reg) ) {
555 return 0xFFFFFFFF; /* disabled */
562 case IDEDATA: return ide_read_data_pio( );
563 case IDEFEAT: return idereg.error;
564 case IDECOUNT:return idereg.count;
565 case IDELBA0: return ide_get_drive_status();
566 case IDELBA1: return idereg.lba1;
567 case IDELBA2: return idereg.lba2;
568 case IDEDEV: return idereg.device;
570 val = ide_read_status();
573 val = MMIO_READ( EXTDMA, reg );
577 MMIO_REGION_READ_DEFSUBFNS(EXTDMA)
580 MMIO_REGION_WRITE_FN( EXTDMA, reg, val )
583 if( !idereg.interface_enabled && IS_IDE_REGISTER(reg) ) {
584 return; /* disabled */
588 case IDEALTSTATUS: /* Device control */
589 ide_write_control( val );
592 ide_write_data_pio( val );
595 if( ide_can_write_regs() )
596 idereg.feature = (uint8_t)val;
599 if( ide_can_write_regs() )
600 idereg.count = (uint8_t)val;
603 if( ide_can_write_regs() )
604 idereg.lba0 = (uint8_t)val;
607 if( ide_can_write_regs() )
608 idereg.lba1 = (uint8_t)val;
611 if( ide_can_write_regs() )
612 idereg.lba2 = (uint8_t)val;
615 if( ide_can_write_regs() )
616 idereg.device = (uint8_t)val;
619 if( ide_can_write_regs() || val == IDE_CMD_NOP ) {
620 ide_write_command( (uint8_t)val );
624 MMIO_WRITE( EXTDMA, reg, val & 0x1FFFFFE0 );
627 MMIO_WRITE( EXTDMA, reg, val & 0x01FFFFFE );
630 MMIO_WRITE( EXTDMA, reg, val & 1 );
634 MMIO_WRITE( EXTDMA, reg, val & 0x01 );
635 asic_ide_dma_transfer( );
638 if( val == 0x001FFFFF ) {
639 idereg.interface_enabled = TRUE;
640 /* Conventional wisdom says that this is necessary but not
641 * sufficient to enable the IDE interface.
643 } else if( val == 0x000042FE ) {
644 idereg.interface_enabled = FALSE;
647 case G2DMA0EXT: case G2DMA0SH4: case G2DMA0SIZ:
648 case G2DMA1EXT: case G2DMA1SH4: case G2DMA1SIZ:
649 case G2DMA2EXT: case G2DMA2SH4: case G2DMA2SIZ:
650 case G2DMA3EXT: case G2DMA3SH4: case G2DMA3SIZ:
651 MMIO_WRITE( EXTDMA, reg, val & 0x9FFFFFE0 );
653 case G2DMA0MOD: case G2DMA1MOD: case G2DMA2MOD: case G2DMA3MOD:
654 MMIO_WRITE( EXTDMA, reg, val & 0x07 );
656 case G2DMA0DIR: case G2DMA1DIR: case G2DMA2DIR: case G2DMA3DIR:
657 MMIO_WRITE( EXTDMA, reg, val & 0x01 );
661 MMIO_WRITE( EXTDMA, reg, val & 1);
662 g2_dma_transfer( 0 );
665 MMIO_WRITE( EXTDMA, reg, val & 0x37 );
669 MMIO_WRITE( EXTDMA, reg, val & 1);
670 g2_dma_transfer( 1 );
674 MMIO_WRITE( EXTDMA, reg, val & 0x37 );
678 MMIO_WRITE( EXTDMA, reg, val &1 );
679 g2_dma_transfer( 2 );
682 MMIO_WRITE( EXTDMA, reg, val & 0x37 );
686 MMIO_WRITE( EXTDMA, reg, val &1 );
687 g2_dma_transfer( 3 );
690 MMIO_WRITE( EXTDMA, reg, val & 0x37 );
694 MMIO_WRITE( EXTDMA, reg, val & 1 );
698 MMIO_WRITE( EXTDMA, reg, val );
.