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vdp fifo, refined timing

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kub 2020-02-25 21:59:02 +01:00
parent e72bc9099c
commit 3c6da92ba0
1 changed files with 31 additions and 29 deletions
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60
pico/videoport.c
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@ -2,6 +2,7 @@
* PicoDrive
* (c) Copyright Dave, 2004
* (C) notaz, 2006-2009
* (C) kub, 2020
*
* This work is licensed under the terms of MAME license.
* See COPYING file in the top-level directory.
@ -58,38 +59,38 @@ static const int vdpsl2cyc_bl[] = { (488<<16)/166, (488<<16)/204 };
// VDP transfer slots in active display 32col mode. 1 slot is 488/171 = 2.8538
// 68k cycles. Only 16 of the 171 slots in a scanline can be used by CPU/DMA:
// (HINT=slot 0): 13,27,42,50,58,74,82,90,106,114,122,138,146,154,169,170
// (HINT=slot 0): 11,25,40,48,56,72,80,88,104,112,120,136,144,152,167,168
static const unsigned char vdpcyc2sl_32[] = { // 68k cycles/4 to slot #
// 4 8 12 16 20 24 28 32 36 40 44 48 52 56 60
0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3,
3, 3, 3, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5,
5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7,
8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9,
9,10,10,10,10,10,10,11,11,11,11,11,11,11,11,11,
11,11,12,12,12,12,12,12,13,13,13,13,13,13,14,14,
14,14,14,14,14,14,14,14,15,16,16,16,16,16,16,16,
0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3,
3, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5,
5, 5, 5, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 8, 8,
8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9,10,
10,10,10,10,10,11,11,11,11,11,11,11,11,11,11,11,
11,12,12,12,12,12,13,13,13,13,13,13,14,14,14,14,
14,14,14,14,14,14,14,15,16,16,16,16,16,16,16,16,
};
static const unsigned char vdpsl2cyc_32[] = { // slot # to 68k cycles/4
0, 9, 19, 30, 35, 41, 52, 58, 64, 75, 81, 87, 98,104,110,120,121,131
0, 8, 18, 28, 33, 39, 51, 56, 62, 74, 79, 85, 97,102,108,119,120,130
};
// VDP transfer slots in active display 40col mode. 1 slot is 488/210 = 2.3238
// 68k cycles. Only 18 of the 210 slots in a scanline can be used by CPU/DMA:
// (HINT=0): 23,49,57,65,81,89,97,113,121,129,145,153,161,177,185,193,208,209
// (HINT=0): 21,47,55,63,79,87,95,111,119,127,143,151,159,175,183,191,206,207,
static const unsigned char vdpcyc2sl_40[] = { // 68k cycles/4 to slot #
// 4 8 12 16 20 24 28 32 36 40 44 48 52 56 60
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2,
2, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5,
5, 5, 5, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7,
7, 8, 8, 8, 8, 8, 9, 9, 9, 9,10,10,10,10,10,10,
10,10,10,10,11,11,11,11,12,12,12,12,12,13,13,13,
13,13,13,13,13,13,14,14,14,14,14,15,15,15,15,15,
16,16,16,16,16,16,16,16,17,18,18,18,18,18,18,18,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2,
3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5,
5, 5, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7,
8, 8, 8, 8, 8, 9, 9, 9, 9,10,10,10,10,10,10,10,
10,10,10,11,11,11,11,12,12,12,12,12,13,13,13,13,
13,13,13,13,13,14,14,14,14,14,15,15,15,15,15,16,
16,16,16,16,16,16,16,17,18,18,18,18,18,18,18,18,
};
static const unsigned char vdpsl2cyc_40[] = { // slot # to 68k cycles/4
0, 13, 28, 33, 37, 47, 51, 56, 65, 70, 74, 84, 88, 93,102,107,112,120,121,135
0, 12, 27, 32, 36, 46, 50, 55, 64, 69, 73, 83, 87, 92,101,106,111,119,120,134
};
// NB code assumes fifo_* arrays have size 2^n
@ -164,7 +165,7 @@ static __inline void SetFIFOState(struct PicoVideo *pv)
if (fifo_total <= 4) {
int x = (fifo_qx + fifo_ql - 1) & 7;
if ((pv->status & SR_DMA) && !(pv->status & PVS_DMAFILL) &&
fifo_ql && !(fifo_queue[x] & FQ_BGDMA)) {
(!fifo_ql || !(fifo_queue[x] & FQ_BGDMA))) {
pv->status &= ~SR_DMA;
pv->command &= ~0x80;
}
@ -263,7 +264,7 @@ int PicoVideoFIFOWrite(int count, int flags, unsigned sr_mask,unsigned sr_flags)
if (count && fifo_ql < 8) {
// update FIFO state if it was empty
if (fifo_ql == 0) {
fifo_slot = GetFIFOSlot(pv, lc+10); // FIFO latency ~4 vdp slots
fifo_slot = GetFIFOSlot(pv, lc+9); // FIFO latency ~3 vdp slots
pv->fifo_cnt = count << (flags & FQ_BYTE);
}
@ -340,7 +341,7 @@ static __inline void AutoIncrement(void)
static __inline void UpdateSAT(u32 a, u32 d)
{
Pico.est.rendstatus |= PDRAW_DIRTY_SPRITES;
if (!((a^sat) >> satxbits) && !(a & 4)) {
if (!(a & 4)) {
int num = (a-sat) >> 3;
((u16 *)&VdpSATCache[num])[(a&3) >> 1] = d;
}
@ -672,7 +673,6 @@ static NOINLINE void CommandDma(void)
fifo_total, SekPc);
fifo_total = fifo_ql = 0;
}
pvid->status |= SR_DMA;
len = GetDmaLength();
source =Pico.video.reg[0x15];
@ -685,7 +685,7 @@ static NOINLINE void CommandDma(void)
else if (method == 3)
DmaCopy(len); // VRAM Copy
else {
pvid->status |= PVS_DMAFILL;
pvid->status |= SR_DMA|PVS_DMAFILL;
return;
}
source += len;
@ -747,7 +747,7 @@ PICO_INTERNAL_ASM void PicoVideoWrite(unsigned int a,unsigned short d)
!(!pvid->pending &&
((pvid->command & 0xc00000f0) == 0x40000010 && PicoMem.vsram[pvid->addr>>1] == (d & 0x7ff)))
)
DrawSync(SekCyclesDone() - Pico.t.m68c_line_start <= 488-440);
DrawSync(0); // XXX it's unclear when vscroll data is fetched from vsram?
if (pvid->pending) {
CommandChange();
@ -902,8 +902,8 @@ update_irq:
static u32 VideoSr(const struct PicoVideo *pv)
{
unsigned int c, d = pv->status;
unsigned int hp = pv->reg[12]&1 ? 32:40; // HBLANK start
unsigned int hl = pv->reg[12]&1 ? 94:84; // HBLANK length
unsigned int hp = pv->reg[12]&1 ? 15*488/210+1 : 15*488/171+1; // HBLANK start
unsigned int hl = pv->reg[12]&1 ? 37*488/210+1 : 28*488/171+1; // HBLANK len
c = SekCyclesDone() - Pico.t.m68c_line_start;
if (c - hp < hl)
@ -1013,7 +1013,9 @@ unsigned char PicoVideoRead8HV_H(void)
unsigned char PicoVideoRead8HV_L(void)
{
u32 d = (SekCyclesDone() - Pico.t.m68c_line_start) & 0x1ff; // FIXME
if (Pico.video.reg[12]&1)
if (Pico.video.reg[0]&2)
d = Pico.video.hv_latch;
else if (Pico.video.reg[12]&1)
d = hcounts_40[d];
else d = hcounts_32[d];
elprintf(EL_HVCNT, "hcounter: %02x [%u] @ %06x", d, SekCyclesDone(), SekPc);