From 3c7a8977ddbdbfb4a8840a487fadade29bd939d6 Mon Sep 17 00:00:00 2001
From: notaz <notasas@gmail.com>
Date: Fri, 25 Aug 2023 23:32:14 +0300
Subject: [PATCH] spu: adjust irqs again

this begs for hw testing, but I don't have the setup right now...

libretro/pcsx_rearmed#746
---
 libpcsxcore/psxdma.c        |  3 +++
 plugins/dfsound/dma.c       | 11 +++++++++++
 plugins/dfsound/externals.h |  2 +-
 plugins/dfsound/registers.c |  7 ++++++-
 plugins/dfsound/spu.c       |  5 ++++-
 5 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/libpcsxcore/psxdma.c b/libpcsxcore/psxdma.c
index 42fb3bab..c0aee7ed 100644
--- a/libpcsxcore/psxdma.c
+++ b/libpcsxcore/psxdma.c
@@ -64,6 +64,9 @@ void psxDma4(u32 madr, u32 bcr, u32 chcr) { // SPU
 				break;
 			SPU_writeDMAMem(ptr, words_copy * 2, psxRegs.cycle);
 			HW_DMA4_MADR = SWAPu32(madr + words_copy * 2);
+			// This should be much slower, like 12+ cycles/byte, it's like
+			// that because the CPU runs too fast and fifo is not emulated.
+			// See also set_dma_end().
 			SPUDMA_INT(words * 4);
 			return;
 
diff --git a/plugins/dfsound/dma.c b/plugins/dfsound/dma.c
index 533d95e9..ada007f0 100644
--- a/plugins/dfsound/dma.c
+++ b/plugins/dfsound/dma.c
@@ -22,6 +22,15 @@
 #include "externals.h"
 #include "registers.h"
 
+static void set_dma_end(int iSize, unsigned int cycles)
+{
+ // this must be > psxdma.c dma irq
+ // Road Rash also wants a considerable delay, maybe because of fifo?
+ cycles += iSize * 20;  // maybe
+ cycles |= 1;           // indicates dma is active
+ spu.cycles_dma_end = cycles;
+}
+
 ////////////////////////////////////////////////////////////////////////
 // READ DMA (many values)
 ////////////////////////////////////////////////////////////////////////
@@ -44,6 +53,7 @@ void CALLBACK SPUreadDMAMem(unsigned short *pusPSXMem, int iSize,
  if (irq && (spu.spuCtrl & CTRL_IRQ))
   log_unhandled("rdma spu irq: %x/%x+%x\n", irq_addr, spu.spuAddr, iSize * 2);
  spu.spuAddr = addr;
+ set_dma_end(iSize, cycles);
 }
 
 ////////////////////////////////////////////////////////////////////////
@@ -78,6 +88,7 @@ void CALLBACK SPUwriteDMAMem(unsigned short *pusPSXMem, int iSize,
  if (irq && (spu.spuCtrl & CTRL_IRQ)) // unhandled because need to implement delay
   log_unhandled("wdma spu irq: %x/%x+%x\n", irq_addr, spu.spuAddr, iSize * 2);
  spu.spuAddr = addr;
+ set_dma_end(iSize, cycles);
 }
 
 ////////////////////////////////////////////////////////////////////////
diff --git a/plugins/dfsound/externals.h b/plugins/dfsound/externals.h
index dd05a5ab..f638b94f 100644
--- a/plugins/dfsound/externals.h
+++ b/plugins/dfsound/externals.h
@@ -197,6 +197,7 @@ typedef struct
  unsigned char * pSpuIrq;
 
  unsigned int    cycles_played;
+ unsigned int    cycles_dma_end;
  int             decode_pos;
  int             decode_dirty_ch;
  unsigned int    bSpuInit:1;
@@ -240,7 +241,6 @@ typedef struct
  int           * SB;
  int           * SSumLR;
 
- int             pad[29];
  unsigned short  regArea[0x400];
 } SPUInfo;
 
diff --git a/plugins/dfsound/registers.c b/plugins/dfsound/registers.c
index ae7ed24e..bcac4d9a 100644
--- a/plugins/dfsound/registers.c
+++ b/plugins/dfsound/registers.c
@@ -133,12 +133,14 @@ void CALLBACK SPUwriteRegister(unsigned long reg, unsigned short val,
     //-------------------------------------------------//
     case H_SPUaddr:
       spu.spuAddr = (unsigned long) val<<3;
+      //check_irq_io(spu.spuAddr);
       break;
     //-------------------------------------------------//
     case H_SPUdata:
       *(unsigned short *)(spu.spuMemC + spu.spuAddr) = HTOLE16(val);
       spu.spuAddr += 2;
       spu.spuAddr &= 0x7fffe;
+      check_irq_io(spu.spuAddr);
       break;
     //-------------------------------------------------//
     case H_SPUctrl:
@@ -160,7 +162,8 @@ void CALLBACK SPUwriteRegister(unsigned long reg, unsigned short val,
     case H_SPUirqAddr:
       //if (val & 1)
       //  log_unhandled("w irq with lsb: %08lx %04x\n", reg, val);
-      spu.pSpuIrq=spu.spuMemC+(((unsigned long) val<<3)&~0xf);
+      spu.pSpuIrq = spu.spuMemC + (((int)val << 3) & ~0xf);
+      //check_irq_io(spu.spuAddr);
       goto upd_irq;
     //-------------------------------------------------//
     case H_SPUrvolL:
@@ -350,11 +353,13 @@ unsigned short CALLBACK SPUreadRegister(unsigned long reg)
     case H_SPUaddr:
      return (unsigned short)(spu.spuAddr>>3);
 
+    // this reportedly doesn't work on real hw
     case H_SPUdata:
      {
       unsigned short s = LE16TOH(*(unsigned short *)(spu.spuMemC + spu.spuAddr));
       spu.spuAddr += 2;
       spu.spuAddr &= 0x7fffe;
+      //check_irq_io(spu.spuAddr);
       return s;
      }
 
diff --git a/plugins/dfsound/spu.c b/plugins/dfsound/spu.c
index 0c4e4f86..fead03c0 100644
--- a/plugins/dfsound/spu.c
+++ b/plugins/dfsound/spu.c
@@ -1154,7 +1154,10 @@ void do_samples(unsigned int cycles_to, int do_direct)
       do_irq();
      }
    }
-  check_irq_io(spu.spuAddr);
+  if (!spu.cycles_dma_end || (int)(spu.cycles_dma_end - cycles_to) < 0) {
+   spu.cycles_dma_end = 0;
+   check_irq_io(spu.spuAddr);
+  }
 
   if (unlikely(spu.rvb->dirty))
    REVERBPrep();
-- 
2.39.2