fix x86emu int10 framebuffer vesa mode.

Change-Id: Iaf91ca90942438a7c94d4c9581d8b702d9f900b5
Signed-off-by: QiaoChong <qiaochong@loongson.cn>

x86emu/int10/generic.c

@@ -272,6 +272,8 @@ unsigned long long  vbios_addr;
 //static unsigned long long * vfb_top;
 void *vbiosMem = 0;
 
+int cacluate_vesamode();
+
 int vga_bios_init(void)
 {
 	xf86Int10InfoPtr pInt;
@@ -644,16 +646,18 @@ int vga_bios_init(void)
 	//printf("setting fb mode...\n");
 	pInt->BIOSseg = V_BIOS >> 4;
 	pInt->num = 0x10;
+	{
 		{
 		char *mode;
 		mode = getenv("vesa_mode");
 		if (mode != 0)
 			vesa_mode = strtol(mode, 0, 0);
 		else
-			vesa_mode = 0x00;
+			vesa_mode = cacluate_vesamode(0);
+		}
 	}
 
-	for(vesa_mode = 0; vesa_mode <= 24; vesa_mode++){
+	for(; vesa_mode>=0 ; vesa_mode = cacluate_vesamode(vesa_mode)){
 		printk("\n\nvesa_mode : 0x%x\n", vesa_mode);
 		pInt->ax = 0x4f02;
 	//	pInt->bx = 0x4114;

x86emu/int10/vesafb.c

@@ -462,6 +462,30 @@ struct vesamode *vesa_mode_head = vesamode;
 
 static u32 io_vaddr;
 
+int cacluate_vesamode(int start)
+{
+	int x,y,depth,mode;
+	int i;
+	x=800;
+	y=600;
+	depth=16;
+	mode=-1;
+#ifdef FB_XSIZE
+	x=FB_XSIZE;
+#endif
+
+#ifdef FB_YSIZE
+	y=FB_YSIZE;
+#endif
+	for(i=start;i<sizeof(vesamode)/sizeof(vesamode[0]);i++)
+		if(x==vesamode[i].width && y==vesamode[i].height && depth==vesamode[i].bpp && vesamode[i].mode>0x107)
+		{
+			mode = i;
+			break;
+		}
+	return mode;
+}
+
 
 void tlbmap(u32 viraddr, u32 phyaddr, u32 size)
 {