Fixes for DMA, so we can have the recent improvements without breaking tons of other game. (SSF2, SFA2, FFMQ, TOP, CT, YI, Probably others). [pagefault]

zsnes/src/cpu/dma.asm

@@ -22,7 +22,8 @@
 
 EXTSYM memtabler8,regptw,snesmap2,snesmmap,memtablew8,regptr,memtabler16
 EXTSYM dmadata,hdmatype,nexthdma,resolutn
-EXTSYM curhdma,curypos,disablehdma,hdmadata,hdmadelay
+EXTSYM curhdma,curypos,disablehdma,hdmadata,hdmadelay,hdmastartsc,hdmarestart
+EXTSYM nohdmaframe
 
 ;*******************************************************
 ; Transfer DMA                     Inits & Transfers DMA
@@ -778,23 +779,16 @@ section .data
            dw 0,1,2,3
 .addrnumt  db 1,2,2,4,4,4,4,4
 
-section .bss
-
-NEWSYM hdmastartsc, resb 1
-NEWSYM hdmarestart, resb 1
-
 section .text
 
 NEWSYM reg420Cw
-
     mov [curhdma],al
     mov bx,[resolutn]
     cmp word[curypos],bx
     jae near .nohdma
+    mov al,[curhdma]
     cmp byte[disablehdma],0
     jne near .nohdma
-;    jmp starthdma
-    mov al,[curhdma]
     mov [nexthdma],al
     cmp al,0
     je near .nohdma
@@ -859,8 +853,6 @@ NEWSYM reg420Cw
     jz .notransh
     call setuphdma
 .notransh
-    mov bl,1
-    mov [hdmadelay],bl
     pop edx
     pop ecx
     pop edi
@@ -869,6 +861,11 @@ NEWSYM reg420Cw
 ;    call exechdma
 ;    call exechdma
 .nohdma
+    cmp byte[nohdmaframe],1
+    jne .notframe
+    inc byte[hdmadelay]
+.notframe
+
     mov byte[hdmarestart],0
     ret
 

zsnes/src/cpu/execute.asm

@@ -1553,6 +1553,9 @@ NEWSYM cpuover
     mov ax,[resolutn]
     cmp word[curypos],ax
     jnb .nodrawline
+    cmp byte[hdmadelay],1
+    jne .virqstuff
+.virqstuff
     cmp byte[hdmadelay],0
     je .dohdma2
     dec byte[hdmadelay]

zsnes/src/cpu/regs.inc

@@ -406,9 +406,12 @@ NEWSYM poamaddrs, dw 0
 NEWSYM ioportval, db 255
 NEWSYM iohvlatch, db 0
 NEWSYM ppustatus, db 0
+NEWSYM hdmastartsc, db 0
+NEWSYM hdmarestart, db 0
+NEWSYM hdmadelay, db 0
+NEWSYM nohdmaframe, db 0           ; no hdma for current frame
 
-
-NEWSYM tempdat, times 477 db 0     ; expandable area
+NEWSYM tempdat, times 474 db 0     ; expandable area
 
 num2writeppureg equ $-sndrot
 ; pharos equ hack *sigh*
@@ -479,6 +482,10 @@ NEWSYM ClearRegs
     mov word[bg3objptr],0
     mov word[bg4objptr],0
     mov byte[ioportval],0FFh
+    mov byte[hdmastartsc],0
+    mov byte[hdmarestart],0
+    mov byte[nohdmaframe],0
+    mov byte[hdmadelay],0
     ret
 
 reg2100r:

zsnes/src/cpu/regsw.inc

@@ -24,7 +24,7 @@ EXTSYM initsfxregsw,reg420Bw,reg420Cw,regptw,initSA1regsw,SDD1Reset
 EXTSYM SPC7110Reset,RTCReset2,debstop,NextLineCache,vidmemch2,vidmemch4
 EXTSYM vidmemch8,vrama,nmirept,sndwrit,SPCRAM,HIRQCycNext,HIRQNextExe,HIRQSkip
 EXTSYM cycpb268,cycpb358,cycpbl,cycpblt,opexec268,opexec268cph,opexec358
-EXTSYM opexec358cph,hdmarestart,printhex8
+EXTSYM opexec358cph,printhex8
 
 SECTION .bss
 NEWSYM testgfxv1, resb 1
@@ -1675,10 +1675,17 @@ reg43x9w:
 
 ; Number of lines for HDMA transfer
 reg43XAw:
+    mov byte[nohdmaframe],0
     xor ebx,ebx
     mov bx,cx
     sub bx,4300h
     mov [dmadata+ebx],al
+    mov bx,[resolutn]
+    cmp word[curypos],bx
+    jb .nodma
+    mov byte[nohdmaframe],1
+    inc byte[hdmadelay]
+.nodma
     ret
 
 regINVALIDw:     ; Invalid Register

zsnes/src/init.asm

@@ -996,7 +996,6 @@ SECTION .data
 NEWSYM disablehdma,    db 0
 NEWSYM disableeffects, db 0
 NEWSYM hdmaearlstart,  db 0
-NEWSYM hdmadelay,      db 0
 NEWSYM disable65816sh, db 0
 NEWSYM disablespcclr,  db 0
 NEWSYM virqnodisable,  db 0