X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=blobdiff_plain;ds=sidebyside;f=cpu%2FDrZ80%2Fdrz80.s;h=499c8566d5a1db6d53fe689f74a667fae7c4f205;hb=04092e329bbd050073d42defcd609550d8545e74;hp=5445ffd08cab973552e071cfdbddd40487006c8e;hpb=ee05564fc7644a035ceeedba61975e46ce84af48;p=picodrive.git

diff --git a/cpu/DrZ80/drz80.s b/cpu/DrZ80/drz80.s
index 5445ffd..499c856 100644
--- a/cpu/DrZ80/drz80.s
+++ b/cpu/DrZ80/drz80.s
@@ -14,12 +14,12 @@
       .equiv INTERRUPT_MODE,         0	;@0 = Use internal int handler, 1 = Use Mames int handler
       .equiv FAST_Z80SP,             1	;@0 = Use mem functions for stack pointer, 1 = Use direct mem pointer
       .equiv UPDATE_CONTEXT,         0
-      .equiv DRZ80_FOR_PICODRIVE,    1
       .equiv DRZ80_XMAP,             1
       .equiv DRZ80_XMAP_MORE_INLINE, 1
 
 .if DRZ80_XMAP
       .equ Z80_MEM_SHIFT, 13
+      ;@ note: stack is locked in single bank that z80sp_base points to
 .endif
 
 .if INTERRUPT_MODE
@@ -144,7 +144,7 @@ z80_xmap_write8_handler: @ data, addr, func
 z80_xmap_read16: @ addr
     @ check if we cross bank boundary
     add r1,r0,#1
-    eor r1,r0,r0
+    eor r1,r1,r0
     tst r1,#1<<Z80_MEM_SHIFT
     bne 0f
 
@@ -160,22 +160,22 @@ z80_xmap_read16: @ addr
 
 0:
     @ z80_xmap_read8 will save r3 and r12 for us
-    stmfd sp!,{r4,r5,lr}
-    mov r4,r0
+    stmfd sp!,{r8,r9,lr}
+    mov r8,r0
     bl z80_xmap_read8
-    mov r5,r0
-    add r0,r4,#1
+    mov r9,r0
+    add r0,r8,#1
     bl z80_xmap_read8
-    orr r0,r5,r0,lsl #8
-    ldmfd sp!,{r4,r5,pc}
+    orr r0,r9,r0,lsl #8
+    ldmfd sp!,{r8,r9,pc}
 
 z80_xmap_write16: @ data, addr
     add r2,r1,#1
-    eor r2,r1,r1
+    eor r2,r2,r1
     tst r2,#1<<Z80_MEM_SHIFT
     bne 0f
 
-    ldr r2,[cpucontext,#z80_read8]
+    ldr r2,[cpucontext,#z80_write8]
     add r2,r2,r1,lsr #Z80_MEM_SHIFT-2
     bic r2,r2,#3
     ldr r2,[r2]
@@ -187,14 +187,30 @@ z80_xmap_write16: @ data, addr
     bx lr
 
 0:
-    stmfd sp!,{r4,r5,lr}
-    mov r4,r0
-    mov r5,r1
+    stmfd sp!,{r8,r9,lr}
+    mov r8,r0
+    mov r9,r1
     bl z80_xmap_write8
-    mov r0,r4,lsr #8
-    add r1,r5,#1
+    mov r0,r8,lsr #8
+    add r1,r9,#1
     bl z80_xmap_write8
-    ldmfd sp!,{r4,r5,pc}
+    ldmfd sp!,{r8,r9,pc}
+
+z80_xmap_rebase_pc:
+    ldr r1,[cpucontext,#z80_read8]
+    mov r2,r0,lsr #Z80_MEM_SHIFT
+    ldr r1,[r1,r2,lsl #2]
+    movs r1,r1,lsl #1
+    strcc r1,[cpucontext,#z80pc_base]
+    addcc z80pc,r1,r0
+    bxcc lr
+
+z80_bad_jump:
+    ldr r0,[cpucontext,#z80_read8]
+    ldr r0,[r0]
+    str r0,[cpucontext,#z80pc_base]
+    mov z80pc,r0
+    bx lr
 .endif
 
 
@@ -335,10 +351,8 @@ z80_xmap_write16: @ data, addr
 .if UPDATE_CONTEXT
      str z80pc,[cpucontext,#z80pc_pointer]
 .endif
-.if DRZ80_FOR_PICODRIVE
-    ldr r1,[cpucontext,#z80pc_base]
-    bic r0,r0,#0xfe000
-    add z80pc,r1,r0
+.if DRZ80_XMAP
+    bl z80_xmap_rebase_pc
 .else
     stmfd sp!,{r3,r12}
 	mov lr,pc
@@ -352,9 +366,10 @@ z80_xmap_write16: @ data, addr
 .if UPDATE_CONTEXT
      str z80pc,[cpucontext,#z80pc_pointer]
 .endif
-.if DRZ80_FOR_PICODRIVE
-    bic r0,r0,#0xfe000
+.if DRZ80_XMAP
+    ;@ XXX: SP is locked to single back z80sp_base points to.
     ldr r1,[cpucontext,#z80sp_base]
+    bic r0,r0,#0x7f<<Z80_MEM_SHIFT
     add r0,r1,r0
 .else
 	stmfd sp!,{r3,r12}
@@ -722,22 +737,9 @@ z80_xmap_write16: @ data, addr
 
 .macro opPOP
 .if FAST_Z80SP
-.if DRZ80_FOR_PICODRIVE
-    @ notaz: try to protect against stack overflows, which tend to happen in Picodrive because of poor timing
-    ldr r2,[cpucontext,#z80sp_base]
-	ldrb r0,[z80sp],#1
-    add r2,r2,#0x2000
-    cmp z80sp,r2
-@    subge z80sp,z80sp,#0x2000 @ unstable?
-	ldrb r1,[z80sp],#1
-    cmp z80sp,r2
-@    subge z80sp,z80sp,#0x2000
-	orr r0,r0,r1, lsl #8
-.else
 	ldrb r0,[z80sp],#1
 	ldrb r1,[z80sp],#1
 	orr r0,r0,r1, lsl #8
-.endif
 .else
 	mov r0,z80sp
 	readmem16
@@ -752,23 +754,22 @@ z80_xmap_write16: @ data, addr
 .endm
 ;@---------------------------------------
 
+.macro stack_check
+    @ try to protect against stack overflows, lock into current bank
+    ldr r1,[cpucontext,#z80sp_base]
+    sub r1,z80sp,r1
+    cmp r1,#2
+    addlt z80sp,z80sp,#1<<Z80_MEM_SHIFT
+.endm
+
 .macro opPUSHareg reg @ reg > r1
 .if FAST_Z80SP
-.if DRZ80_FOR_PICODRIVE
-    @ notaz: try to protect against stack overflows, which tend to happen in Picodrive because of poor timing
-    ldr r0,[cpucontext,#z80sp_base]
-    cmp z80sp,r0
-    addle z80sp,z80sp,#0x2000
-    mov r1,\reg, lsr #8
-	strb r1,[z80sp,#-1]!
-    cmp z80sp,r0
-    addle z80sp,z80sp,#0x2000
-	strb \reg,[z80sp,#-1]!
-.else
+.if DRZ80_XMAP
+	stack_check
+.endif
 	mov r1,\reg, lsr #8
 	strb r1,[z80sp,#-1]!
 	strb \reg,[z80sp,#-1]!
-.endif
 .else
     mov r0,\reg
 	sub z80sp,z80sp,#2
@@ -779,22 +780,13 @@ z80_xmap_write16: @ data, addr
 
 .macro opPUSHreg reg
 .if FAST_Z80SP
-.if DRZ80_FOR_PICODRIVE
-    ldr r0,[cpucontext,#z80sp_base]
-    cmp z80sp,r0
-    addle z80sp,z80sp,#0x2000
-    mov r1,\reg, lsr #24
-	strb r1,[z80sp,#-1]!
-    cmp z80sp,r0
-    addle z80sp,z80sp,#0x2000
-	mov r1,\reg, lsr #16
-	strb r1,[z80sp,#-1]!
-.else
+.if DRZ80_XMAP
+	stack_check
+.endif
     mov r1,\reg, lsr #24
 	strb r1,[z80sp,#-1]!
 	mov r1,\reg, lsr #16
 	strb r1,[z80sp,#-1]!
-.endif
 .else
 	mov r0,\reg,lsr #16
 	sub z80sp,z80sp,#2
@@ -6721,7 +6713,8 @@ opcode_DD_2E:
 opcode_DD_34:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r0,r0,r1, lsr #16
+	add r0,r1,r0, lsl #16
+	mov r0,r0,lsr #16
 	stmfd sp!,{r0}	;@ save addr
 	readmem8
 	opINC8b
@@ -6732,7 +6725,8 @@ opcode_DD_34:
 opcode_DD_35:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r0,r0,r1, lsr #16
+	add r0,r1,r0, lsl #16
+	mov r0,r0,lsr #16
 	stmfd sp!,{r0}	;@ save addr
 	readmem8
 	opDEC8b
@@ -6744,7 +6738,8 @@ opcode_DD_36:
 	ldrsb r2,[z80pc],#1
 	ldrb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r1,r2,r1, lsr #16
+	add r1,r1,r2, lsl #16
+	mov r1,r1,lsr #16
 	writemem8
 	fetch 19
 ;@ADD IX,SP
@@ -6775,7 +6770,8 @@ opcode_DD_45:
 opcode_DD_46:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r0,r0,r1, lsr #16
+	add r0,r1,r0, lsl #16
+	mov r0,r0,lsr #16
 	readmem8
 	and z80bc,z80bc,#0xFF<<16
 	orr z80bc,z80bc,r0, lsl #24
@@ -6796,7 +6792,8 @@ opcode_DD_4D:
 opcode_DD_4E:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r0,r0,r1, lsr #16
+	add r0,r1,r0, lsl #16
+	mov r0,r0,lsr #16
 	readmem8
 	and z80bc,z80bc,#0xFF<<24
 	orr z80bc,z80bc,r0, lsl #16
@@ -6818,7 +6815,8 @@ opcode_DD_55:
 opcode_DD_56:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r0,r0,r1, lsr #16
+	add r0,r1,r0, lsl #16
+	mov r0,r0,lsr #16
 	readmem8
 	and z80de,z80de,#0xFF<<16
 	orr z80de,z80de,r0, lsl #24
@@ -6839,7 +6837,8 @@ opcode_DD_5D:
 opcode_DD_5E:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r0,r0,r1, lsr #16
+	add r0,r1,r0, lsl #16
+	mov r0,r0,lsr #16
 	readmem8
 	and z80de,z80de,#0xFF<<24
 	orr z80de,z80de,r0, lsl #16
@@ -6876,7 +6875,8 @@ opcode_DD_65:
 opcode_DD_66:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r0,r0,r1, lsr #16
+	add r0,r1,r0, lsl #16
+	mov r0,r0,lsr #16
 	readmem8
 	and z80hl,z80hl,#0xFF<<16
 	orr z80hl,z80hl,r0, lsl #24
@@ -6918,7 +6918,8 @@ opcode_DD_6D:
 opcode_DD_6E:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r0,r0,r1, lsr #16
+	add r0,r1,r0, lsl #16
+	mov r0,r0,lsr #16
 	readmem8
 	and z80hl,z80hl,#0xFF<<24
 	orr z80hl,z80hl,r0, lsl #16
@@ -6933,7 +6934,8 @@ opcode_DD_6F:
 opcode_DD_70:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r1,r0,r1, lsr #16
+	add r1,r1,r0, lsl #16
+	mov r1,r1,lsr #16
 	mov r0,z80bc, lsr #24
 	writemem8
 	fetch 19
@@ -6941,7 +6943,8 @@ opcode_DD_70:
 opcode_DD_71:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r1,r0,r1, lsr #16
+	add r1,r1,r0, lsl #16
+	mov r1,r1,lsr #16
 	mov r0,z80bc, lsr #16
 	and r0,r0,#0xFF
 	writemem8
@@ -6950,7 +6953,8 @@ opcode_DD_71:
 opcode_DD_72:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r1,r0,r1, lsr #16
+	add r1,r1,r0, lsl #16
+	mov r1,r1,lsr #16
 	mov r0,z80de, lsr #24
 	writemem8
 	fetch 19
@@ -6958,7 +6962,8 @@ opcode_DD_72:
 opcode_DD_73:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r1,r0,r1, lsr #16
+	add r1,r1,r0, lsl #16
+	mov r1,r1,lsr #16
 	mov r0,z80de, lsr #16
 	and r0,r0,#0xFF
 	writemem8
@@ -6967,7 +6972,8 @@ opcode_DD_73:
 opcode_DD_74:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r1,r0,r1, lsr #16
+	add r1,r1,r0, lsl #16
+	mov r1,r1,lsr #16
 	mov r0,z80hl, lsr #24
 	writemem8
 	fetch 19
@@ -6975,7 +6981,8 @@ opcode_DD_74:
 opcode_DD_75:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r1,r0,r1, lsr #16
+	add r1,r1,r0, lsl #16
+	mov r1,r1,lsr #16
 	mov r0,z80hl, lsr #16
 	and r0,r0,#0xFF
 	writemem8
@@ -6984,7 +6991,8 @@ opcode_DD_75:
 opcode_DD_77:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r1,r0,r1, lsr #16
+	add r1,r1,r0, lsl #16
+	mov r1,r1,lsr #16
 	mov r0,z80a, lsr #24
 	writemem8
 	fetch 19
@@ -7003,7 +7011,8 @@ opcode_DD_7D:
 opcode_DD_7E:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r0,r0,r1, lsr #16
+	add r0,r1,r0, lsl #16
+	mov r0,r0,lsr #16
 	readmem8
 	mov z80a,r0, lsl #24
 	fetch 19
@@ -7022,7 +7031,8 @@ opcode_DD_85:
 opcode_DD_86:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r0,r0,r1, lsr #16
+	add r0,r1,r0, lsl #16
+	mov r0,r0,lsr #16
 	readmem8
 	opADDb
 	fetch 19
@@ -7041,7 +7051,8 @@ opcode_DD_8D:
 opcode_DD_8E:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r0,r0,r1, lsr #16
+	add r0,r1,r0, lsl #16
+	mov r0,r0,lsr #16
 	readmem8
 	opADCb
 	fetch 19
@@ -7060,7 +7071,8 @@ opcode_DD_95:
 opcode_DD_96:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r0,r0,r1, lsr #16
+	add r0,r1,r0, lsl #16
+	mov r0,r0,lsr #16
 	readmem8
 	opSUBb
 	fetch 19
@@ -7079,7 +7091,8 @@ opcode_DD_9D:
 opcode_DD_9E:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r0,r0,r1, lsr #16
+	add r0,r1,r0, lsl #16
+	mov r0,r0,lsr #16
 	readmem8
 	opSBCb
 	fetch 19
@@ -7098,7 +7111,8 @@ opcode_DD_A5:
 opcode_DD_A6:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r0,r0,r1, lsr #16
+	add r0,r1,r0, lsl #16
+	mov r0,r0,lsr #16
 	readmem8
 	opANDb
 	fetch 19
@@ -7117,7 +7131,8 @@ opcode_DD_AD:
 opcode_DD_AE:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r0,r0,r1, lsr #16
+	add r0,r1,r0, lsl #16
+	mov r0,r0,lsr #16
 	readmem8
 	opXORb
 	fetch 19
@@ -7136,7 +7151,8 @@ opcode_DD_B5:
 opcode_DD_B6:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r0,r0,r1, lsr #16
+	add r0,r1,r0, lsl #16
+	mov r0,r0,lsr #16
 	readmem8
 	opORb
 	fetch 19
@@ -7155,7 +7171,8 @@ opcode_DD_BD:
 opcode_DD_BE:
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r0,r0,r1, lsr #16
+	add r0,r1,r0, lsl #16
+	mov r0,r0,lsr #16
 	readmem8
 	opCPb
 	fetch 19
@@ -7167,7 +7184,8 @@ opcode_DD_CB:
 ;@moves the PC to the location of the subroutine
 	ldrsb r0,[z80pc],#1
 	ldr r1,[z80xx]
-	add r0,r0,r1, lsr #16
+	add r0,r1,r0, lsl #16
+	mov r0,r0,lsr #16
 
 	ldrb r1,[z80pc],#1
 	ldr pc,[pc,r1, lsl #2]