ARM7 BIOS read protect.

(noting that Super Princess Peach reads from the BIOS. probably a bug)

3 files changed, 33 insertions, 12 deletions

diff --git a/ARM.cpp b/ARM.cpp
index 80ba82b..bdd48ce 100644
--- a/ARM.cpp
+++ b/ARM.cpp
@@ -371,6 +371,8 @@ s32 ARM::Execute()
             }
         }
 
+        //if (R[15]==0x037F9364) printf("R8=%08X R9=%08X\n", R[8], R[9]);
+
         // TODO optimize this shit!!!
         if (Halted)
         {
diff --git a/NDS.cpp b/NDS.cpp
index 217a524..d7a8503 100644
--- a/NDS.cpp
+++ b/NDS.cpp
@@ -82,6 +82,8 @@ u8 PostFlag7;
 u16 PowerControl9;
 u16 PowerControl7;
 
+u16 ARM7BIOSProt;
+
 Timer Timers[8];
 
 DMA* DMAs[8];
@@ -190,6 +192,8 @@ void SetupDirectBoot()
 
     PowerControl9 = 0x820F;
     GPU::DisplaySwap(PowerControl9);
+
+    ARM7BIOSProt = 0x1204;
 }
 
 void Reset()
@@ -240,6 +244,8 @@ void Reset()
     PowerControl9 = 0x0001;
     PowerControl7 = 0x0001;
 
+    ARM7BIOSProt = 0;
+
     IPCSync9 = 0;
     IPCSync7 = 0;
     IPCFIFOCnt9 = 0;
@@ -815,7 +821,7 @@ u16 ARM9Read16(u32 addr)
         return 0xFFFF;
     }
 
-    printf("unknown arm9 read16 %08X %08X %08X %08X\n", addr, ARM9->R[15], ARM9->R[1], ARM9->R[2]);
+    //printf("unknown arm9 read16 %08X %08X %08X %08X\n", addr, ARM9->R[15], ARM9->R[1], ARM9->R[2]);
     return 0;
 }
 
@@ -937,7 +943,7 @@ void ARM9Write16(u32 addr, u16 val)
         return;
     }
 
-    printf("unknown arm9 write16 %08X %04X\n", addr, val);
+    //printf("unknown arm9 write16 %08X %04X\n", addr, val);
 }
 
 void ARM9Write32(u32 addr, u32 val)
@@ -991,7 +997,11 @@ u8 ARM7Read8(u32 addr)
 {
     if (addr < 0x00004000)
     {
-        if (ARM7->R[15] > 0x4000) printf("BAD BIOS READ8 %08X FROM %08X\n", addr, ARM7->R[15]);
+        if (ARM7->R[15] >= 0x4000)
+            return 0xFF;
+        if (addr < ARM7BIOSProt && ARM7->R[15] >= ARM7BIOSProt)
+            return 0xFF;
+
         return *(u8*)&ARM7BIOS[addr];
     }
 
@@ -1030,7 +1040,11 @@ u16 ARM7Read16(u32 addr)
 {
     if (addr < 0x00004000)
     {
-        if (ARM7->R[15] > 0x4000) printf("BAD BIOS READ16 %08X FROM %08X\n", addr, ARM7->R[15]);
+        if (ARM7->R[15] >= 0x4000)
+            return 0xFFFF;
+        if (addr < ARM7BIOSProt && ARM7->R[15] >= ARM7BIOSProt)
+            return 0xFFFF;
+
         return *(u16*)&ARM7BIOS[addr];
     }
 
@@ -1072,12 +1086,11 @@ u32 ARM7Read32(u32 addr)
 {
     if (addr < 0x00004000)
     {
-        if (ARM7->R[15] > 0x4000) {
-                printf("BAD BIOS READ32 %08X FROM %08X | %08X %08X\n", addr, ARM7->R[15], ARM7Read32(0x03807758+12), ARM7Read32(0x03807758+4));
-                Halt();
-        return 0xFFFFFFFF;
-        }
-        //if (addr < 0x1204 && ARM7->R[15] >= 0x1204) printf("BAD BIOS READ32 %08X FROM %08X\n", addr, ARM7->R[15]);
+        if (ARM7->R[15] >= 0x4000)
+            return 0xFFFFFFFF;
+        if (addr < ARM7BIOSProt && ARM7->R[15] >= ARM7BIOSProt)
+            return 0xFFFFFFFF;
+
         return *(u32*)&ARM7BIOS[addr];
     }
 
@@ -1818,6 +1831,7 @@ u16 ARM7IORead16(u32 addr)
 
     case 0x04000300: return PostFlag7;
     case 0x04000304: return PowerControl7;
+    case 0x04000308: return ARM7BIOSProt;
 
     case 0x04000504: return _soundbias;
     }
@@ -2044,6 +2058,11 @@ void ARM7IOWrite16(u32 addr, u16 val)
 
     case 0x04000304: PowerControl7 = val; return;
 
+    case 0x04000308:
+        if (ARM7BIOSProt == 0)
+            ARM7BIOSProt = val;
+        return;
+
     case 0x04000504: // removeme
         _soundbias = val & 0x3FF;
         return;
diff --git a/melonDS.depend b/melonDS.depend
index 77cdb91..1eca451 100644
--- a/melonDS.depend
+++ b/melonDS.depend
@@ -10,7 +10,7 @@
 
 1481161027 c:\documents\sources\melonds\types.h
 
-1486309683 source:c:\documents\sources\melonds\nds.cpp
+1486310027 source:c:\documents\sources\melonds\nds.cpp
 	<stdio.h>
 	<string.h>
 	"NDS.h"
@@ -24,7 +24,7 @@
 	"RTC.h"
 	"Wifi.h"
 
-1486309562 source:c:\documents\sources\melonds\arm.cpp
+1486310306 source:c:\documents\sources\melonds\arm.cpp
 	<stdio.h>
 	"NDS.h"
 	"ARM.h"