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picodrive/Pico/VideoPort.c
notaz cea6590346 fast dma 
git-svn-id: file:///home/notaz/opt/svn/PicoDrive@35 be3aeb3a-fb24-0410-a615-afba39da0efa
2007-02-09 23:39:03 +00:00

466 lines
13 KiB
C
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// This is part of Pico Library
// (c) Copyright 2004 Dave, All rights reserved.
// (c) Copyright 2006 notaz, All rights reserved.
// Free for non-commercial use.
// For commercial use, separate licencing terms must be obtained.
#include "PicoInt.h"
extern const unsigned char hcounts_32[];
extern const unsigned char hcounts_40[];
extern const unsigned short vcounts[];
extern int rendstatus;
typedef unsigned char u8;
typedef unsigned short u16;
static __inline void AutoIncrement()
{
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;
rendstatus|=0x10; break;
case 3: Pico.m.dirtyPal = 1;
//dprintf("w[%i] @ %04x, inc=%i [%i|%i]", Pico.video.type, a, Pico.video.reg[0xf], Pico.m.scanline, SekCyclesDone());
Pico.cram [(a>>1)&0x003f]=d; break; // wraps (Desert Strike)
case 5: Pico.vsram[(a>>1)&0x003f]=d; break;
}
//dprintf("w[%i] @ %04x, inc=%i [%i|%i]", Pico.video.type, a, Pico.video.reg[0xf], Pico.m.scanline, SekCyclesDone());
AutoIncrement();
}
static unsigned int VideoRead()
{
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;
}
AutoIncrement();
return d;
}
static int GetDmaLength()
{
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;
dprintf("DmaSlow[%i] %06x->%04x len %i inc=%i blank %i [%i|%i] @ %x",
Pico.video.type, source, a, len, inc, (Pico.video.status&8)||!(Pico.video.reg[1]&0x40),
Pico.m.scanline, SekCyclesDone(), SekPc);
if(Pico.m.scanline != -1) {
Pico.m.dma_bytes += len;
SekSetCyclesLeft(SekCyclesLeft - CheckDMA());
} else {
// be approximate in non-accurate mode
SekSetCyclesLeft(SekCyclesLeft - (len*(((488<<8)/167))>>8));
}
if ((source&0xe00000)==0xe00000) { // Ram
pd=(u16 *)(Pico.ram+(source&0xfffe));
pdend=(u16 *)(Pico.ram+0x10000);
} else if(PicoMCD & 1) {
dprintf("DmaSlow CD");
if(source<0x20000) { // Bios area
pd=(u16 *)(Pico_mcd->bios+(source&~1));
pdend=(u16 *)(Pico_mcd->bios+0x20000);
} else if ((source&0xfc0000)==0x200000 && (!(Pico_mcd->s68k_regs[3]&4))) { // Word Ram
if (!(Pico_mcd->s68k_regs[3]&4)) { // 2M mode
source -= 2;
pd=(u16 *)(Pico_mcd->word_ram+(source&0x3fffe));
pdend=(u16 *)(Pico_mcd->word_ram+0x40000);
} else {
dprintf("DmaSlow: unsupported src");
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 {
dprintf("DmaSlow: unsupported src");
return;
}
} else {
if(source<Pico.romsize) { // Rom
pd=(u16 *)(Pico.rom+(source&~1));
pdend=(u16 *)(Pico.rom+Pico.romsize);
} else {
dprintf("DmaSlow: invalid dma src");
return;
}
}
// overflow protection, might break something..
if (len > pdend - pd) {
len = pdend - pd;
dprintf("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|=0x10;
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;
}
// 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;
dprintf("DmaCopy len %i [%i|%i]", len, Pico.m.scanline, SekCyclesDone());
Pico.m.dma_bytes += len;
if(Pico.m.scanline != -1)
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|=0x10;
}
// 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();
dprintf("DmaFill len %i inc %i [%i|%i]", len, inc, Pico.m.scanline, SekCyclesDone());
Pico.m.dma_bytes += len;
if(Pico.m.scanline != -1)
Pico.video.status|=2; // dma busy (in accurate mode)
// 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|=0x10;
}
static void CommandDma()
{
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()
{
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;
//dprintf("addr set: %04x", addr);
// Check for dma:
if (cmd&0x80) CommandDma();
}
void PicoVideoWrite(unsigned int a,unsigned short d)
{
struct PicoVideo *pvid=&Pico.video;
a&=0x1c;
if (a==0x00) // Data port 0 or 2
{
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
{
VideoWrite(d);
}
return;
}
if (a==0x04) // Control (command) port 4 or 6
{
//dprintf("vdp cw(%04x), p=%i @ %06x [%i]", d, pvid->pending, SekPc, SekCyclesDone());
if(pvid->pending)
{
// 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;
if(num==00) dprintf("hint_onoff: %i->%i [%i|%i] pend=%i @ %06x", (pvid->reg[0]&0x10)>>4, (d&0x10)>>4, Pico.m.scanline, SekCyclesDone(), (pvid->pending_ints&0x10)>>4, SekPc);
if(num==01) dprintf("vint_onoff: %i->%i [%i|%i] pend=%i @ %06x", (pvid->reg[1]&0x20)>>5, (d&0x20)>>5, Pico.m.scanline, SekCyclesDone(), (pvid->pending_ints&0x20)>>5, SekPc);
//if(num==01) dprintf("set_blank: %i @ %06x [%i|%i]", !((d&0x40)>>6), SekPc, Pico.m.scanline, SekCyclesDone());
//if(num==05) dprintf("spr_set: %i @ %06x [%i|%i]", (unsigned char)d, SekPc, Pico.m.scanline, SekCyclesDone());
//if(num==10) dprintf("hint_set: %i @ %06x [%i|%i]", (unsigned char)d, SekPc, Pico.m.scanline, SekCyclesDone());
pvid->reg[num]=(unsigned char)d;
#if !(defined(EMU_C68K) && defined(EMU_M68K)) // not debugging Cyclone
// update IRQ level (Lemmings, Wiz 'n' Liz intro, ... )
// may break if done improperly:
// International Superstar Soccer Deluxe (crash), Street Racer (logos), Burning Force (gfx), Fatal Rewind (hang), Sesame Street Counting Cafe
if(num < 2) {
#ifdef EMU_C68K
// hack: make sure we do not touch the irq line if Cyclone is just about to take the IRQ
if (PicoCpu.irq <= (PicoCpu.srh&7)) {
#endif
int lines, pints;
lines = (pvid->reg[1] & 0x20) | (pvid->reg[0] & 0x10);
pints = (pvid->pending_ints&lines);
if(pints & 0x20) SekInterrupt(6);
else if(pints & 0x10) SekInterrupt(4);
else SekInterrupt(0);
#ifdef EMU_C68K
// adjust cycles for Cyclone so it would take the int "in time"
if(PicoCpu.irq) {
SekEndRun(24);
}
}
#endif
}
else
#endif
if(num == 5) rendstatus|=1;
else if(num == 0xc) Pico.m.dirtyPal = 2; // renderers should update their palettes if sh/hi mode is changed
pvid->type=0; // register writes clear command (else no Sega logo in Golden Axe II)
} else {
// High word of command:
pvid->command&=0x0000ffff;
pvid->command|=d<<16;
pvid->pending=1;
}
}
}
}
unsigned int PicoVideoRead(unsigned int a)
{
unsigned int d=0;
a&=0x1c;
if (a==0x00) // data port
{
d=VideoRead();
goto end;
}
if (a==0x04) // control port
{
d=Pico.video.status;
if(PicoOpt&0x10) d|=0x0020; // sprite collision (Shadow of the Beast)
if(Pico.m.rotate++&8) d|=0x0100; else d|=0x0200; // Toggle fifo full empty (who uses that stuff?)
if(!(Pico.video.reg[1]&0x40)) d|=0x0008; // set V-Blank if display is disabled
if(SekCyclesLeft < 84+4) d|=0x0004; // H-Blank (Sonic3 vs)
// dprintf("sr_read %04x @ %06x [%i|%i]", d, SekPc, Pico.m.scanline, SekCyclesDone());
Pico.video.pending=0; // ctrl port reads clear write-pending flag (Charles MacDonald)
goto end;
}
// 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 hc;
if(Pico.m.scanline != -1) {
int lineCycles=(488-SekCyclesLeft)&0x1ff;
d=Pico.m.scanline; // V-Counter
if(Pico.video.reg[12]&1)
hc=hcounts_40[lineCycles];
else hc=hcounts_32[lineCycles];
//if(lineCycles > 488-12) d++; // Wheel of Fortune
} else {
// get approximate V-Counter
d=vcounts[SekCyclesDone()>>8];
hc = Pico.m.rotate&0xff;
}
if(Pico.m.pal) {
if(d >= 0x103) d-=56; // based on Gens
} else {
if(d >= 0xEB) d-=6;
}
if((Pico.video.reg[12]&6) == 6) {
// interlace mode 2 (Combat Cars (UE) [!])
d <<= 1;
if (d&0xf00) d|= 1;
}
dprintf("hv: %02x %02x (%i) @ %06x", hc, d, SekCyclesDone(), SekPc);
d&=0xff; d<<=8;
d|=hc;
goto end;
}
end:
return d;
}
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