From: notaz <notasas@gmail.com>
Date: Sat, 30 Sep 2017 21:59:44 +0000 (+0300)
Subject: slightly better z80 vdp reads
X-Git-Tag: v1.92~17
X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=75b84e4b7c446cf42a2838834b5d50a4059709fe;p=picodrive.git

slightly better z80 vdp reads
---

diff --git a/pico/memory.c b/pico/memory.c
index 0907696a..34ef99d6 100644
--- a/pico/memory.c
+++ b/pico/memory.c
@@ -703,10 +703,21 @@ void PicoWrite16_io(u32 a, u32 d)
 
 // VDP area (0xc00000 - 0xdfffff)
 // TODO: verify if lower byte goes to PSG on word writes
-static u32 PicoRead8_vdp(u32 a)
+u32 PicoRead8_vdp(u32 a)
 {
-  if ((a & 0x00e0) == 0x0000)
-    return PicoVideoRead8(a);
+  if ((a & 0x00f0) == 0x0000) {
+    switch (a & 0x0d)
+    {
+      case 0x00: return PicoVideoRead8DataH();
+      case 0x01: return PicoVideoRead8DataL();
+      case 0x04: return PicoVideoRead8CtlH();
+      case 0x05: return PicoVideoRead8CtlL();
+      case 0x08:
+      case 0x0c: return PicoVideoRead8HV_H();
+      case 0x09:
+      case 0x0d: return PicoVideoRead8HV_L();
+    }
+  }
 
   elprintf(EL_UIO|EL_ANOMALY, "68k bad read [%06x] @%06x", a, SekPc);
   return 0;
@@ -1184,8 +1195,19 @@ void PicoWrite16_32x(u32 a, u32 d) {}
 
 static unsigned char z80_md_vdp_read(unsigned short a)
 {
-  if ((a & 0x00e0) == 0x0000)
-    return PicoVideoRead8(a); // FIXME: depends on 68k cycles
+  if ((a & 0x00f0) == 0x0000) {
+    switch (a & 0x0d)
+    {
+      case 0x00: return PicoVideoRead8DataH();
+      case 0x01: return PicoVideoRead8DataL();
+      case 0x04: return PicoVideoRead8CtlH();
+      case 0x05: return PicoVideoRead8CtlL();
+      case 0x08:
+      case 0x0c: return get_scanline(1); // FIXME: make it proper
+      case 0x09:
+      case 0x0d: return Pico.m.rotate++;
+    }
+  }
 
   elprintf(EL_ANOMALY, "z80 invalid r8 [%06x] %02x", a, 0xff);
   return 0xff;
diff --git a/pico/memory_amips.s b/pico/memory_amips.s
index 4f09198f..b11c2e28 100644
--- a/pico/memory_amips.s
+++ b/pico/memory_amips.s
@@ -468,7 +468,7 @@ m_read8_vdp:
     or      $t0, $t1
     bnez    $t0, m_read_null # invalid address
     nop
-    j       PicoVideoRead8
+    j       PicoRead8_vdp
     nop
 
 m_read8_ram:
diff --git a/pico/pico_int.h b/pico/pico_int.h
index 12769315..97b7b0e4 100644
--- a/pico/pico_int.h
+++ b/pico/pico_int.h
@@ -793,7 +793,12 @@ void ym2612_unpack_state(void);
 extern int line_base_cycles;
 PICO_INTERNAL_ASM void PicoVideoWrite(unsigned int a,unsigned short d);
 PICO_INTERNAL_ASM unsigned int PicoVideoRead(unsigned int a);
-PICO_INTERNAL_ASM unsigned int PicoVideoRead8(unsigned int a);
+unsigned char PicoVideoRead8DataH(void);
+unsigned char PicoVideoRead8DataL(void);
+unsigned char PicoVideoRead8CtlH(void);
+unsigned char PicoVideoRead8CtlL(void);
+unsigned char PicoVideoRead8HV_H(void);
+unsigned char PicoVideoRead8HV_L(void);
 extern int (*PicoDmaHook)(unsigned int source, int len, unsigned short **base, unsigned int *mask);
 
 // misc.c
diff --git a/pico/videoport.c b/pico/videoport.c
index fe96139f..0af4bbcc 100644
--- a/pico/videoport.c
+++ b/pico/videoport.c
@@ -563,43 +563,54 @@ PICO_INTERNAL_ASM unsigned int PicoVideoRead(unsigned int a)
   return 0;
 }
 
-unsigned int PicoVideoRead8(unsigned int a)
+unsigned char PicoVideoRead8DataH(void)
 {
-  unsigned int d;
-  a&=0x1d;
+  return VideoRead() >> 8;
+}
 
-  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;
-  }
+unsigned char PicoVideoRead8DataL(void)
+{
+  return VideoRead();
+}
 
-  return 0;
+// FIXME: broken mess
+unsigned char PicoVideoRead8CtlH(void)
+{
+  u8 d = (u8)(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;
+}
+
+unsigned char PicoVideoRead8CtlL(void)
+{
+  u8 d = (u8)Pico.video.status;
+  //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;
+}
+
+unsigned char PicoVideoRead8HV_H(void)
+{
+  elprintf(EL_HVCNT, "vcounter: %02x (%i) @ %06x", Pico.video.v_counter, SekCyclesDone(), SekPc);
+  return Pico.video.v_counter;
+}
+
+// FIXME: broken
+unsigned char PicoVideoRead8HV_L(void)
+{
+  u32 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;
 }
 
 // vim:shiftwidth=2:ts=2:expandtab