[mubios] Extend registers from 16-bit to 32-bit

Signed-off-by: Richard Qin <richard.qin.x@gmail.com>

5 files changed, 30 insertions, 43 deletions

diff --git a/mubios/arch/interrupt.S b/mubios/arch/interrupt.S
index 0822b1a..b3a461b 100644
--- a/mubios/arch/interrupt.S
+++ b/mubios/arch/interrupt.S
@@ -53,21 +53,11 @@ int1a_return:
 	.type \name, @function
 
 \name:
-		# Build struct bios_regs on the interrupted real-mode stack.
-		push 0
-		push es
+		# Build struct bios_regs from the pushad and segment frames.
 		push ds
-		push bp
-		push di
-		push si
-		push dx
-		push cx
-		push bx
-		push ax
-
-		mov bp, sp
-		mov ax, word ptr [bp + 24]
-		mov word ptr [bp + 18], ax
+		push es
+		.byte 0x66
+		pushad
 
 		# ESI = linear address of struct bios_regs.
 		movzx esi, sp
@@ -88,16 +78,10 @@ int1a_return:
 		call enter_protected_service
 
 		# Restore the context modified by the C service.
-		pop ax
-		pop bx
-		pop cx
-		pop dx
-		pop si
-		pop di
-		pop bp
-		pop ds
+		.byte 0x66
+		popad
 		pop es
-		add sp, 2
+		pop ds
 		iret
 	.endm
 
diff --git a/mubios/core/interrupt.c b/mubios/core/interrupt.c
index 3f5bbb9..a9b3ce6 100644
--- a/mubios/core/interrupt.c
+++ b/mubios/core/interrupt.c
@@ -36,7 +36,7 @@ bios_service_dispatch (u8 vector, struct bios_regs *regs)
       break;
 
     default:
-      regs->ax = 0x0100u;
+      regs->eax = 0x0100u;
       regs->flags |= 0x0001u;
       break;
     }
diff --git a/mubios/include/regs.h b/mubios/include/regs.h
index eeafe6b..350a825 100644
--- a/mubios/include/regs.h
+++ b/mubios/include/regs.h
@@ -26,15 +26,18 @@
 
 struct bios_regs
 {
-  u16 ax;
-  u16 bx;
-  u16 cx;
-  u16 dx;
-  u16 si;
-  u16 di;
-  u16 bp;
-  u16 ds;
+  u32 edi;
+  u32 esi;
+  u32 ebp;
+  u32 esp;
+  u32 ebx;
+  u32 edx;
+  u32 ecx;
+  u32 eax;
   u16 es;
+  u16 ds;
+  u16 return_ip;
+  u16 return_cs;
   u16 flags;
 };
 
diff --git a/mubios/services/int10.c b/mubios/services/int10.c
index 76a1c1d..0e63ef2 100644
--- a/mubios/services/int10.c
+++ b/mubios/services/int10.c
@@ -44,7 +44,7 @@ int10_service (struct bios_regs *regs)
   u8 attribute;
   u16 position;
 
-  function = (u8)(regs->ax >> 8);
+  function = (u8)(regs->eax >> 8);
 
   if (function != 0x0Eu)
     return;
@@ -52,8 +52,8 @@ int10_service (struct bios_regs *regs)
   cursor = (volatile u16 *)BDA_CURSOR;
   video = (volatile u16 *)VGA_TEXT_BASE;
 
-  character = (u8)regs->ax;
-  attribute = (u8)regs->bx;
+  character = (u8)regs->eax;
+  attribute = (u8)regs->ebx;
   position = *cursor;
 
   if (character == 0x0Du)
diff --git a/mubios/services/int13.c b/mubios/services/int13.c
index e5cef43..2c12261 100644
--- a/mubios/services/int13.c
+++ b/mubios/services/int13.c
@@ -38,7 +38,7 @@ struct edd_packet
 static void
 int13_fail (struct bios_regs *regs)
 {
-  regs->ax = 0x0100u;
+  regs->eax = 0x0100u;
   regs->flags |= BIOS_CF;
 }
 
@@ -47,7 +47,7 @@ get_edd_packet (struct bios_regs *regs)
 {
   u32 address;
 
-  address = ((u32)regs->ds << 4) + regs->si;
+  address = ((u32)regs->ds << 4) + (u16)regs->esi;
   return (struct edd_packet *)address;
 }
 
@@ -58,19 +58,19 @@ int13_service (struct bios_regs *regs)
   struct edd_packet *packet;
   u32 buffer_address;
 
-  function = (u8)(regs->ax >> 8);
+  function = (u8)(regs->eax >> 8);
 
   if (function == 0x41u)
     {
-      if (regs->bx != 0x55AAu)
+      if (regs->ebx != 0x55AAu)
         {
           int13_fail (regs);
           return;
         }
 
-      regs->ax = 0x3000u;
-      regs->bx = 0xAA55u;
-      regs->cx |= 0x0001u;
+      regs->eax = 0x3000u;
+      regs->ebx = 0xAA55u;
+      regs->ecx |= 0x0001u;
       regs->flags &= (u16)~BIOS_CF;
       return;
     }
@@ -98,7 +98,7 @@ int13_service (struct bios_regs *regs)
           return;
         }
 
-      regs->ax = 0;
+      regs->eax = 0;
       regs->flags &= (u16)~BIOS_CF;
       return;
     }