From 54604e030df86ba542633e543c5bd269b2e391bc Mon Sep 17 00:00:00 2001
From: notaz <notasas@gmail.com>
Date: Wed, 5 Jul 2023 00:12:44 +0300
Subject: [PATCH] spu: irq adjustments according to MiSTer

libretro/pcsx_rearmed#725
---
 plugins/dfsound/dma.c       | 61 ++++++++++++++++++++++---------------
 plugins/dfsound/externals.h |  1 +
 plugins/dfsound/registers.c |  2 ++
 plugins/dfsound/spu.c       | 14 ++++++++-
 4 files changed, 52 insertions(+), 26 deletions(-)

diff --git a/plugins/dfsound/dma.c b/plugins/dfsound/dma.c
index 43019f1d..eb85a731 100644
--- a/plugins/dfsound/dma.c
+++ b/plugins/dfsound/dma.c
@@ -20,6 +20,7 @@
 #define _IN_DMA
 
 #include "externals.h"
+#include "registers.h"
 
 ////////////////////////////////////////////////////////////////////////
 // READ DMA (one value)
@@ -28,6 +29,7 @@
 unsigned short CALLBACK SPUreadDMA(void)
 {
  unsigned short s = *(unsigned short *)(spu.spuMemC + spu.spuAddr);
+ check_irq_io(spu.spuAddr);
  spu.spuAddr += 2;
  spu.spuAddr &= 0x7fffe;
 
@@ -41,26 +43,27 @@ unsigned short CALLBACK SPUreadDMA(void)
 void CALLBACK SPUreadDMAMem(unsigned short *pusPSXMem, int iSize,
  unsigned int cycles)
 {
- int i;
+ unsigned int addr = spu.spuAddr, irq_addr = regAreaGet(H_SPUirqAddr) << 3;
+ int i, irq;
 
  do_samples_if_needed(cycles, 1);
-
- for(i=0;i<iSize;i++)
-  {
-   *pusPSXMem++ = *(unsigned short *)(spu.spuMemC + spu.spuAddr);
-   spu.spuAddr += 2;
-   spu.spuAddr &= 0x7fffe;
-  }
+ irq = addr <= irq_addr && irq_addr < addr + iSize*2;
+
+ for(i = 0; i < iSize; i++)
+ {
+  *pusPSXMem++ = *(unsigned short *)(spu.spuMemC + addr);
+  addr += 2;
+  addr &= 0x7fffe;
+ }
+ if (irq && (spu.spuCtrl & CTRL_IRQ))
+  log_unhandled("rdma spu irq: %x/%x+%x\n", irq_addr, spu.spuAddr, iSize * 2);
+ spu.spuAddr = addr;
 }
 
 ////////////////////////////////////////////////////////////////////////
 ////////////////////////////////////////////////////////////////////////
 ////////////////////////////////////////////////////////////////////////
 
-// to investigate: do sound data updates by writedma affect spu
-// irqs? Will an irq be triggered, if new data is written to
-// the memory irq address?
-
 ////////////////////////////////////////////////////////////////////////
 // WRITE DMA (one value)
 ////////////////////////////////////////////////////////////////////////
@@ -69,6 +72,7 @@ void CALLBACK SPUwriteDMA(unsigned short val)
 {
  *(unsigned short *)(spu.spuMemC + spu.spuAddr) = val;
 
+ check_irq_io(spu.spuAddr);
  spu.spuAddr += 2;
  spu.spuAddr &= 0x7fffe;
  spu.bMemDirty = 1;
@@ -81,24 +85,31 @@ void CALLBACK SPUwriteDMA(unsigned short val)
 void CALLBACK SPUwriteDMAMem(unsigned short *pusPSXMem, int iSize,
  unsigned int cycles)
 {
- int i;
+ unsigned int addr = spu.spuAddr, irq_addr = regAreaGet(H_SPUirqAddr) << 3;
+ int i, irq;
  
  do_samples_if_needed(cycles, 1);
  spu.bMemDirty = 1;
-
- if(spu.spuAddr + iSize*2 < 0x80000)
-  {
-   memcpy(spu.spuMemC + spu.spuAddr, pusPSXMem, iSize*2);
-   spu.spuAddr += iSize*2;
-   return;
-  }
-
- for(i=0;i<iSize;i++)
+ irq = addr <= irq_addr && irq_addr < addr + iSize*2;
+
+ if (addr + iSize*2 < 0x80000)
+ {
+  memcpy(spu.spuMemC + addr, pusPSXMem, iSize*2);
+  addr += iSize*2;
+ }
+ else
+ {
+  irq |= irq_addr < ((addr + iSize*2) & 0x7ffff);
+  for (i = 0; i < iSize; i++)
   {
-   *(unsigned short *)(spu.spuMemC + spu.spuAddr) = *pusPSXMem++;
-   spu.spuAddr += 2;
-   spu.spuAddr &= 0x7fffe;
+   *(unsigned short *)(spu.spuMemC + addr) = *pusPSXMem++;
+   addr += 2;
+   addr &= 0x7fffe;
   }
+ }
+ 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;
 }
 
 ////////////////////////////////////////////////////////////////////////
diff --git a/plugins/dfsound/externals.h b/plugins/dfsound/externals.h
index 51574121..f42ceff1 100644
--- a/plugins/dfsound/externals.h
+++ b/plugins/dfsound/externals.h
@@ -253,6 +253,7 @@ extern SPUInfo spu;
 
 void do_samples(unsigned int cycles_to, int do_sync);
 void schedule_next_irq(void);
+void check_irq_io(unsigned int addr);
 
 #define do_samples_if_needed(c, sync) \
  do { \
diff --git a/plugins/dfsound/registers.c b/plugins/dfsound/registers.c
index e00939e6..a8fb59ed 100644
--- a/plugins/dfsound/registers.c
+++ b/plugins/dfsound/registers.c
@@ -149,6 +149,8 @@ void CALLBACK SPUwriteRegister(unsigned long reg, unsigned short val,
       goto rvbd;
     //-------------------------------------------------//
     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);
       goto upd_irq;
     //-------------------------------------------------//
diff --git a/plugins/dfsound/spu.c b/plugins/dfsound/spu.c
index 1127cd71..7f8ab1df 100644
--- a/plugins/dfsound/spu.c
+++ b/plugins/dfsound/spu.c
@@ -212,7 +212,7 @@ static void do_irq(void)
 
 static int check_irq(int ch, unsigned char *pos)
 {
- if((spu.spuCtrl & CTRL_IRQ) && pos == spu.pSpuIrq)
+ if((spu.spuCtrl & (CTRL_ON|CTRL_IRQ)) == (CTRL_ON|CTRL_IRQ) && pos == spu.pSpuIrq)
  {
   //printf("ch%d irq %04x\n", ch, pos - spu.spuMemC);
   do_irq();
@@ -221,6 +221,17 @@ static int check_irq(int ch, unsigned char *pos)
  return 0;
 }
 
+void check_irq_io(unsigned int addr)
+{
+ unsigned int irq_addr = regAreaGet(H_SPUirqAddr) << 3;
+ //addr &= ~7; // ?
+ if((spu.spuCtrl & (CTRL_ON|CTRL_IRQ)) == (CTRL_ON|CTRL_IRQ) && addr == irq_addr)
+ {
+  //printf("io   irq %04x\n", irq_addr);
+  do_irq();
+ }
+}
+
 ////////////////////////////////////////////////////////////////////////
 // START SOUND... called by main thread to setup a new sound on a channel
 ////////////////////////////////////////////////////////////////////////
@@ -1136,6 +1147,7 @@ void do_samples(unsigned int cycles_to, int do_direct)
       do_irq();
      }
    }
+  check_irq_io(spu.spuAddr);
 
   if (unlikely(spu.rvb->dirty))
    REVERBPrep();
-- 
2.39.5