BizHawk/waterbox/picodrive/pico/videoport.c

550 lines
16 KiB
C

/*
* PicoDrive
* (c) Copyright Dave, 2004
* (C) notaz, 2006-2009
*
* This work is licensed under the terms of MAME license.
* See COPYING file in the top-level directory.
*/
#include "pico_int.h"
int line_base_cycles;
extern const unsigned char hcounts_32[];
extern const unsigned char hcounts_40[];
#ifndef UTYPES_DEFINED
typedef unsigned char u8;
typedef unsigned short u16;
typedef unsigned int u32;
#define UTYPES_DEFINED
#endif
int (*PicoDmaHook)(unsigned int source, int len, unsigned short **srcp, unsigned short **limitp) = NULL;
static __inline void AutoIncrement(void)
{
Pico.video.addr=(unsigned short)(Pico.video.addr+Pico.video.reg[0xf]);
}
static void VideoWrite(u16 d)
{
unsigned int a=Pico.video.addr;
switch (Pico.video.type)
{
case 1: if(a&1) d=(u16)((d<<8)|(d>>8)); // If address is odd, bytes are swapped (which game needs this?)
Pico.vram [(a>>1)&0x7fff]=d;
if (a - ((unsigned)(Pico.video.reg[5]&0x7f) << 9) < 0x400)
rendstatus |= PDRAW_DIRTY_SPRITES;
break;
case 3: Pico.m.dirtyPal = 1;
Pico.cram [(a>>1)&0x003f]=d; break; // wraps (Desert Strike)
case 5: Pico.vsram[(a>>1)&0x003f]=d; break;
//default:elprintf(EL_ANOMALY, "VDP write %04x with bad type %i", d, Pico.video.type); break;
}
AutoIncrement();
}
static unsigned int VideoRead(void)
{
unsigned int a=0,d=0;
a=Pico.video.addr; a>>=1;
switch (Pico.video.type)
{
case 0: d=Pico.vram [a&0x7fff]; break;
case 8: d=Pico.cram [a&0x003f]; break;
case 4: d=Pico.vsram[a&0x003f]; break;
default:elprintf(EL_ANOMALY, "VDP read with bad type %i", Pico.video.type); break;
}
AutoIncrement();
return d;
}
static int GetDmaLength(void)
{
struct PicoVideo *pvid=&Pico.video;
int len=0;
// 16-bit words to transfer:
len =pvid->reg[0x13];
len|=pvid->reg[0x14]<<8;
// Charles MacDonald:
if(!len) len = 0xffff;
return len;
}
static void DmaSlow(int len)
{
u16 *pd=0, *pdend, *r;
unsigned int a=Pico.video.addr, a2, d;
unsigned char inc=Pico.video.reg[0xf];
unsigned int source;
source =Pico.video.reg[0x15]<<1;
source|=Pico.video.reg[0x16]<<9;
source|=Pico.video.reg[0x17]<<17;
elprintf(EL_VDPDMA, "DmaSlow[%i] %06x->%04x len %i inc=%i blank %i [%i] @ %06x",
Pico.video.type, source, a, len, inc, (Pico.video.status&8)||!(Pico.video.reg[1]&0x40),
SekCyclesDone(), SekPc);
Pico.m.dma_xfers += len;
SekCyclesBurnRun(CheckDMA());
if ((source&0xe00000)==0xe00000) { // Ram
pd=(u16 *)(Pico.ram+(source&0xfffe));
pdend=(u16 *)(Pico.ram+0x10000);
}
else if (PicoAHW & PAHW_MCD)
{
elprintf(EL_VDPDMA, "DmaSlow CD, r3=%02x", Pico_mcd->s68k_regs[3]);
if(source<0x20000) { // Bios area
pd=(u16 *)(Pico_mcd->bios+(source&~1));
pdend=(u16 *)(Pico_mcd->bios+0x20000);
} else if ((source&0xfc0000)==0x200000) { // Word Ram
source -= 2;
if (!(Pico_mcd->s68k_regs[3]&4)) { // 2M mode
pd=(u16 *)(Pico_mcd->word_ram2M+(source&0x3fffe));
pdend=(u16 *)(Pico_mcd->word_ram2M+0x40000);
} else {
if (source < 0x220000) { // 1M mode
int bank = Pico_mcd->s68k_regs[3]&1;
pd=(u16 *)(Pico_mcd->word_ram1M[bank]+(source&0x1fffe));
pdend=(u16 *)(Pico_mcd->word_ram1M[bank]+0x20000);
} else {
DmaSlowCell(source, a, len, inc);
return;
}
}
} else if ((source&0xfe0000)==0x020000) { // Prg Ram
u8 *prg_ram = Pico_mcd->prg_ram_b[Pico_mcd->s68k_regs[3]>>6];
pd=(u16 *)(prg_ram+(source&0x1fffe));
pdend=(u16 *)(prg_ram+0x20000);
} else {
elprintf(EL_VDPDMA|EL_ANOMALY, "DmaSlow[%i] %06x->%04x: FIXME: unsupported src", Pico.video.type, source, a);
return;
}
}
else
{
// if we have DmaHook, let it handle ROM because of possible DMA delay
if (PicoDmaHook && PicoDmaHook(source, len, &pd, &pdend));
else if (source<Pico.romsize) { // Rom
pd=(u16 *)(Pico.rom+(source&~1));
pdend=(u16 *)(Pico.rom+Pico.romsize);
}
else {
elprintf(EL_VDPDMA|EL_ANOMALY, "DmaSlow[%i] %06x->%04x: invalid src", Pico.video.type, source, a);
return;
}
}
// overflow protection, might break something..
if (len > pdend - pd) {
len = pdend - pd;
elprintf(EL_VDPDMA|EL_ANOMALY, "DmaSlow overflow");
}
switch (Pico.video.type)
{
case 1: // vram
r = Pico.vram;
if (inc == 2 && !(a&1) && a+len*2 < 0x10000)
{
// most used DMA mode
memcpy16(r + (a>>1), pd, len);
a += len*2;
}
else
{
for(; len; len--)
{
d=*pd++;
if(a&1) d=(d<<8)|(d>>8);
r[a>>1] = (u16)d; // will drop the upper bits
// AutoIncrement
a=(u16)(a+inc);
// didn't src overlap?
//if(pd >= pdend) pd-=0x8000; // should be good for RAM, bad for ROM
}
}
rendstatus |= PDRAW_DIRTY_SPRITES;
break;
case 3: // cram
Pico.m.dirtyPal = 1;
r = Pico.cram;
for(a2=a&0x7f; len; len--)
{
r[a2>>1] = (u16)*pd++; // bit 0 is ignored
// AutoIncrement
a2+=inc;
// didn't src overlap?
//if(pd >= pdend) pd-=0x8000;
// good dest?
if(a2 >= 0x80) break; // Todds Adventures in Slime World / Andre Agassi tennis
}
a=(a&0xff00)|a2;
break;
case 5: // vsram[a&0x003f]=d;
r = Pico.vsram;
for(a2=a&0x7f; len; len--)
{
r[a2>>1] = (u16)*pd++;
// AutoIncrement
a2+=inc;
// didn't src overlap?
//if(pd >= pdend) pd-=0x8000;
// good dest?
if(a2 >= 0x80) break;
}
a=(a&0xff00)|a2;
break;
default:
if (Pico.video.type != 0 || (EL_LOGMASK & EL_VDPDMA))
elprintf(EL_VDPDMA|EL_ANOMALY, "DMA with bad type %i", Pico.video.type);
break;
}
// remember addr
Pico.video.addr=(u16)a;
}
static void DmaCopy(int len)
{
u16 a=Pico.video.addr;
unsigned char *vr = (unsigned char *) Pico.vram;
unsigned char *vrs;
unsigned char inc=Pico.video.reg[0xf];
int source;
elprintf(EL_VDPDMA, "DmaCopy len %i [%i]", len, SekCyclesDone());
Pico.m.dma_xfers += len;
Pico.video.status |= 2; // dma busy
source =Pico.video.reg[0x15];
source|=Pico.video.reg[0x16]<<8;
vrs=vr+source;
if (source+len > 0x10000) len=0x10000-source; // clip??
for (; len; len--)
{
vr[a] = *vrs++;
// AutoIncrement
a=(u16)(a+inc);
}
// remember addr
Pico.video.addr=a;
rendstatus |= PDRAW_DIRTY_SPRITES;
}
// check: Contra, Megaman
// note: this is still inaccurate
static void DmaFill(int data)
{
int len;
unsigned short a=Pico.video.addr;
unsigned char *vr=(unsigned char *) Pico.vram;
unsigned char high = (unsigned char) (data >> 8);
unsigned char inc=Pico.video.reg[0xf];
len=GetDmaLength();
elprintf(EL_VDPDMA, "DmaFill len %i inc %i [%i]", len, inc, SekCyclesDone());
Pico.m.dma_xfers += len;
Pico.video.status |= 2; // dma busy
// from Charles MacDonald's genvdp.txt:
// Write lower byte to address specified
vr[a] = (unsigned char) data;
a=(u16)(a+inc);
if (!inc) len=1;
for (; len; len--) {
// Write upper byte to adjacent address
// (here we are byteswapped, so address is already 'adjacent')
vr[a] = high;
// Increment address register
a=(u16)(a+inc);
}
// remember addr
Pico.video.addr=a;
// update length
Pico.video.reg[0x13] = Pico.video.reg[0x14] = 0; // Dino Dini's Soccer (E) (by Haze)
rendstatus |= PDRAW_DIRTY_SPRITES;
}
static void CommandDma(void)
{
struct PicoVideo *pvid=&Pico.video;
int len=0,method=0;
if ((pvid->reg[1]&0x10)==0) return; // DMA not enabled
len=GetDmaLength();
method=pvid->reg[0x17]>>6;
if (method< 2) DmaSlow(len); // 68000 to VDP
if (method==3) DmaCopy(len); // VRAM Copy
}
static void CommandChange(void)
{
struct PicoVideo *pvid=&Pico.video;
unsigned int cmd=0,addr=0;
cmd=pvid->command;
// Get type of transfer 0xc0000030 (v/c/vsram read/write)
pvid->type=(unsigned char)(((cmd>>2)&0xc)|(cmd>>30));
// Get address 0x3fff0003
addr =(cmd>>16)&0x3fff;
addr|=(cmd<<14)&0xc000;
pvid->addr=(unsigned short)addr;
// Check for dma:
if (cmd&0x80) CommandDma();
}
static void DrawSync(int blank_on)
{
if (Pico.m.scanline < 224 && !(PicoOpt & POPT_ALT_RENDERER) &&
!PicoSkipFrame && DrawScanline <= Pico.m.scanline) {
//elprintf(EL_ANOMALY, "sync");
PicoDrawSync(Pico.m.scanline, blank_on);
}
}
PICO_INTERNAL_ASM void PicoVideoWrite(unsigned int a,unsigned short d)
{
struct PicoVideo *pvid=&Pico.video;
//if (Pico.m.scanline < 224)
// elprintf(EL_STATUS, "PicoVideoWrite [%06x] %04x", a, d);
a&=0x1c;
if (a==0x00) // Data port 0 or 2
{
// try avoiding the sync..
if (Pico.m.scanline < 224 && (pvid->reg[1]&0x40) &&
!(!pvid->pending &&
((pvid->command & 0xc00000f0) == 0x40000010 && Pico.vsram[pvid->addr>>1] == d))
)
DrawSync(0);
if (pvid->pending) {
CommandChange();
pvid->pending=0;
}
// If a DMA fill has been set up, do it
if ((pvid->command&0x80) && (pvid->reg[1]&0x10) && (pvid->reg[0x17]>>6)==2)
{
DmaFill(d);
}
else
{
// preliminary FIFO emulation for Chaos Engine, The (E)
if (!(pvid->status&8) && (pvid->reg[1]&0x40) && !(PicoOpt&POPT_DIS_VDP_FIFO)) // active display?
{
pvid->status&=~0x200; // FIFO no longer empty
pvid->lwrite_cnt++;
if (pvid->lwrite_cnt >= 4) pvid->status|=0x100; // FIFO full
if (pvid->lwrite_cnt > 4) {
SekCyclesBurnRun(32); // penalty // 488/12-8
}
elprintf(EL_ASVDP, "VDP data write: %04x [%06x] {%i} #%i @ %06x", d, Pico.video.addr,
Pico.video.type, pvid->lwrite_cnt, SekPc);
}
VideoWrite(d);
}
return;
}
if (a==0x04) // Control (command) port 4 or 6
{
if (pvid->pending)
{
if (d & 0x80) DrawSync(0); // only need sync for DMA
// Low word of command:
pvid->command&=0xffff0000;
pvid->command|=d;
pvid->pending=0;
CommandChange();
}
else
{
if ((d&0xc000)==0x8000)
{
// Register write:
int num=(d>>8)&0x1f;
int dold=pvid->reg[num];
int blank_on = 0;
pvid->type=0; // register writes clear command (else no Sega logo in Golden Axe II)
if (num > 0x0a && !(pvid->reg[1]&4)) {
elprintf(EL_ANOMALY, "%02x written to reg %02x in SMS mode @ %06x", d, num, SekPc);
return;
}
if (num == 1 && !(d&0x40) && SekCyclesDone() - line_base_cycles <= 488-390)
blank_on = 1;
DrawSync(blank_on);
pvid->reg[num]=(unsigned char)d;
switch (num)
{
case 0x00:
elprintf(EL_INTSW, "hint_onoff: %i->%i [%i] pend=%i @ %06x", (dold&0x10)>>4,
(d&0x10)>>4, SekCyclesDone(), (pvid->pending_ints&0x10)>>4, SekPc);
goto update_irq;
case 0x01:
elprintf(EL_INTSW, "vint_onoff: %i->%i [%i] pend=%i @ %06x", (dold&0x20)>>5,
(d&0x20)>>5, SekCyclesDone(), (pvid->pending_ints&0x20)>>5, SekPc);
goto update_irq;
case 0x05:
//elprintf(EL_STATUS, "spritep moved to %04x", (unsigned)(Pico.video.reg[5]&0x7f) << 9);
if (d^dold) rendstatus |= PDRAW_SPRITES_MOVED;
break;
case 0x0c:
// renderers should update their palettes if sh/hi mode is changed
if ((d^dold)&8) Pico.m.dirtyPal = 2;
break;
}
return;
update_irq:
#ifndef EMU_CORE_DEBUG
// update IRQ level
if (!SekShouldInterrupt()) // hack
{
int lines, pints, irq=0;
lines = (pvid->reg[1] & 0x20) | (pvid->reg[0] & 0x10);
pints = (pvid->pending_ints&lines);
if (pints & 0x20) irq = 6;
else if (pints & 0x10) irq = 4;
SekInterrupt(irq); // update line
if (irq) SekEndRun(24); // make it delayed
}
#endif
}
else
{
// High word of command:
pvid->command&=0x0000ffff;
pvid->command|=d<<16;
pvid->pending=1;
}
}
}
}
PICO_INTERNAL_ASM unsigned int PicoVideoRead(unsigned int a)
{
a&=0x1c;
if (a==0x04) // control port
{
struct PicoVideo *pv=&Pico.video;
unsigned int d;
d=pv->status;
//if (PicoOpt&POPT_ALT_RENDERER) d|=0x0020; // sprite collision (Shadow of the Beast)
if (SekCyclesDone() - line_base_cycles >= 488-88)
d|=0x0004; // H-Blank (Sonic3 vs)
d |= ((pv->reg[1]&0x40)^0x40) >> 3; // set V-Blank if display is disabled
d |= (pv->pending_ints&0x20)<<2; // V-int pending?
if (d&0x100) pv->status&=~0x100; // FIFO no longer full
pv->pending = 0; // ctrl port reads clear write-pending flag (Charles MacDonald)
elprintf(EL_SR, "SR read: %04x @ %06x", d, SekPc);
return d;
}
// H-counter info (based on Generator):
// frame:
// | <- hblank? -> |
// start <416> hint <36> hdisplay <38> end // CPU cycles
// |---------...---------|------------|-------------|
// 0 B6 E4 FF // 40 cells
// 0 93 E8 FF // 32 cells
// Gens (?) v-render
// start <hblank=84> hint hdisplay <404> |
// |---------------------|--------------------------|
// E4 (hc[0x43]==0) 07 B1 // 40
// E8 (hc[0x45]==0) 05 91 // 32
// check: Sonic 3D Blast bonus, Cannon Fodder, Chase HQ II, 3 Ninjas kick back, Road Rash 3, Skitchin', Wheel of Fortune
if ((a&0x1c)==0x08)
{
unsigned int d;
d = (SekCyclesDone() - line_base_cycles) & 0x1ff; // FIXME
if (Pico.video.reg[12]&1)
d = hcounts_40[d];
else d = hcounts_32[d];
elprintf(EL_HVCNT, "hv: %02x %02x (%i) @ %06x", d, Pico.video.v_counter, SekCyclesDone(), SekPc);
return d | (Pico.video.v_counter << 8);
}
if (a==0x00) // data port
{
return VideoRead();
}
return 0;
}
unsigned int PicoVideoRead8(unsigned int a)
{
unsigned int d;
a&=0x1d;
switch (a)
{
case 0: return VideoRead() >> 8;
case 1: return VideoRead() & 0xff;
case 4: // control port/status reg
d = Pico.video.status >> 8;
if (d&1) Pico.video.status&=~0x100; // FIFO no longer full
Pico.video.pending = 0;
elprintf(EL_SR, "SR read (h): %02x @ %06x", d, SekPc);
return d;
case 5:
d = Pico.video.status & 0xff;
//if (PicoOpt&POPT_ALT_RENDERER) d|=0x0020; // sprite collision (Shadow of the Beast)
d |= ((Pico.video.reg[1]&0x40)^0x40) >> 3; // set V-Blank if display is disabled
d |= (Pico.video.pending_ints&0x20)<<2; // V-int pending?
if (SekCyclesDone() - line_base_cycles >= 488-88) d |= 4; // H-Blank
Pico.video.pending = 0;
elprintf(EL_SR, "SR read (l): %02x @ %06x", d, SekPc);
return d;
case 8: // hv counter
elprintf(EL_HVCNT, "vcounter: %02x (%i) @ %06x", Pico.video.v_counter, SekCyclesDone(), SekPc);
return Pico.video.v_counter;
case 9:
d = (SekCyclesDone() - line_base_cycles) & 0x1ff; // FIXME
if (Pico.video.reg[12]&1)
d = hcounts_40[d];
else d = hcounts_32[d];
elprintf(EL_HVCNT, "hcounter: %02x (%i) @ %06x", d, SekCyclesDone(), SekPc);
return d;
}
return 0;
}
// vim:shiftwidth=2:ts=2:expandtab