vgabios: Remove dummy 0xfe mode from list of cirrus modes.
[seabios.git] / vgasrc / clext.c
index 36ccad3556176f468f7aee855baa9e3ae9094a9e..ec0380f908bde4211e82fa3185ff1f0f20b5bac3 100644 (file)
@@ -5,13 +5,23 @@
 //
 // This file may be distributed under the terms of the GNU LGPLv3 license.
 
-#include "vgatables.h" // cirrus_init
+#include "clext.h" // clext_init
+#include "vgabios.h" // VBE_VENDOR_STRING
 #include "biosvar.h" // GET_GLOBAL
 #include "util.h" // dprintf
+#include "bregs.h" // struct bregs
+#include "vbe.h" // struct vbe_info
+#include "stdvga.h" // VGAREG_SEQU_ADDRESS
+
+
+/****************************************************************
+ * tables
+ ****************************************************************/
 
 struct cirrus_mode_s {
     /* + 0 */
     u16 mode;
+    u8 memmodel;
     u16 width;
     u16 height;
     u16 depth;
@@ -22,7 +32,6 @@ struct cirrus_mode_s {
     u16 *crtc; /* 0x3d4 */
     /* +16 */
     u8 bitsperpixel;
-    u8 vesacolortype;
     u8 vesaredmask;
     u8 vesaredpos;
     u8 vesagreenmask;
@@ -231,64 +240,70 @@ static u16 ccrtc_1600x1200x8[] VAR16 = {
 };
 
 static struct cirrus_mode_s cirrus_modes[] VAR16 = {
-    {0x5f,640,480,8,0x00,
+    {0x5f,MM_PACKED,640,480,8,0x00,
      cseq_640x480x8,cgraph_svgacolor,ccrtc_640x480x8,8,
-     4,0,0,0,0,0,0,0,0},
-    {0x64,640,480,16,0xe1,
+     0,0,0,0,0,0,0,0},
+    {0x64,MM_DIRECT,640,480,16,0xe1,
      cseq_640x480x16,cgraph_svgacolor,ccrtc_640x480x16,16,
-     6,5,11,6,5,5,0,0,0},
-    {0x66,640,480,15,0xf0,
+     5,11,6,5,5,0,0,0},
+    {0x66,MM_DIRECT,640,480,15,0xf0,
      cseq_640x480x16,cgraph_svgacolor,ccrtc_640x480x16,16,
-     6,5,10,5,5,5,0,1,15},
-    {0x71,640,480,24,0xe5,
+     5,10,5,5,5,0,1,15},
+    {0x71,MM_DIRECT,640,480,24,0xe5,
      cseq_640x480x24,cgraph_svgacolor,ccrtc_640x480x24,24,
-     6,8,16,8,8,8,0,0,0},
+     8,16,8,8,8,0,0,0},
 
-    {0x5c,800,600,8,0x00,
+    {0x5c,MM_PACKED,800,600,8,0x00,
      cseq_800x600x8,cgraph_svgacolor,ccrtc_800x600x8,8,
-     4,0,0,0,0,0,0,0,0},
-    {0x65,800,600,16,0xe1,
+     0,0,0,0,0,0,0,0},
+    {0x65,MM_DIRECT,800,600,16,0xe1,
      cseq_800x600x16,cgraph_svgacolor,ccrtc_800x600x16,16,
-     6,5,11,6,5,5,0,0,0},
-    {0x67,800,600,15,0xf0,
+     5,11,6,5,5,0,0,0},
+    {0x67,MM_DIRECT,800,600,15,0xf0,
      cseq_800x600x16,cgraph_svgacolor,ccrtc_800x600x16,16,
-     6,5,10,5,5,5,0,1,15},
+     5,10,5,5,5,0,1,15},
 
-    {0x60,1024,768,8,0x00,
+    {0x60,MM_PACKED,1024,768,8,0x00,
      cseq_1024x768x8,cgraph_svgacolor,ccrtc_1024x768x8,8,
-     4,0,0,0,0,0,0,0,0},
-    {0x74,1024,768,16,0xe1,
+     0,0,0,0,0,0,0,0},
+    {0x74,MM_DIRECT,1024,768,16,0xe1,
      cseq_1024x768x16,cgraph_svgacolor,ccrtc_1024x768x16,16,
-     6,5,11,6,5,5,0,0,0},
-    {0x68,1024,768,15,0xf0,
+     5,11,6,5,5,0,0,0},
+    {0x68,MM_DIRECT,1024,768,15,0xf0,
      cseq_1024x768x16,cgraph_svgacolor,ccrtc_1024x768x16,16,
-     6,5,10,5,5,5,0,1,15},
+     5,10,5,5,5,0,1,15},
 
-    {0x78,800,600,24,0xe5,
+    {0x78,MM_DIRECT,800,600,24,0xe5,
      cseq_800x600x24,cgraph_svgacolor,ccrtc_800x600x24,24,
-     6,8,16,8,8,8,0,0,0},
-    {0x79,1024,768,24,0xe5,
+     8,16,8,8,8,0,0,0},
+    {0x79,MM_DIRECT,1024,768,24,0xe5,
      cseq_1024x768x24,cgraph_svgacolor,ccrtc_1024x768x24,24,
-     6,8,16,8,8,8,0,0,0},
+     8,16,8,8,8,0,0,0},
 
-    {0x6d,1280,1024,8,0x00,
+    {0x6d,MM_PACKED,1280,1024,8,0x00,
      cseq_1280x1024x8,cgraph_svgacolor,ccrtc_1280x1024x8,8,
-     4,0,0,0,0,0,0,0,0},
-    {0x69,1280,1024,15,0xf0,
+     0,0,0,0,0,0,0,0},
+    {0x69,MM_DIRECT,1280,1024,15,0xf0,
      cseq_1280x1024x16,cgraph_svgacolor,ccrtc_1280x1024x16,16,
-     6,5,10,5,5,5,0,1,15},
-    {0x75,1280,1024,16,0xe1,
+     5,10,5,5,5,0,1,15},
+    {0x75,MM_DIRECT,1280,1024,16,0xe1,
      cseq_1280x1024x16,cgraph_svgacolor,ccrtc_1280x1024x16,16,
-     6,5,11,6,5,5,0,0,0},
+     5,11,6,5,5,0,0,0},
 
-    {0x7b,1600,1200,8,0x00,
+    {0x7b,MM_PACKED,1600,1200,8,0x00,
      cseq_1600x1200x8,cgraph_svgacolor,ccrtc_1600x1200x8,8,
-     4,0,0,0,0,0,0,0,0},
-
-    {0xfe,0,0,0,0,cseq_vga,cgraph_vga,ccrtc_vga,0,
-     0xff,0,0,0,0,0,0,0,0},
+     0,0,0,0,0,0,0,0},
 };
 
+static struct cirrus_mode_s mode_switchback VAR16 =
+    {0xfe,0xff,0,0,0,0,cseq_vga,cgraph_vga,ccrtc_vga,0,
+     0,0,0,0,0,0,0,0};
+
+
+/****************************************************************
+ * helper functions
+ ****************************************************************/
+
 static struct cirrus_mode_s *
 cirrus_get_modeentry(u8 mode)
 {
@@ -314,14 +329,6 @@ cirrus_switch_mode_setregs(u16 *data, u16 port)
     }
 }
 
-static u16
-cirrus_get_crtc(void)
-{
-    if (inb(VGAREG_READ_MISC_OUTPUT) & 1)
-        return VGAREG_VGA_CRTC_ADDRESS;
-    return VGAREG_MDA_CRTC_ADDRESS;
-}
-
 static void
 cirrus_switch_mode(struct cirrus_mode_s *table)
 {
@@ -329,7 +336,7 @@ cirrus_switch_mode(struct cirrus_mode_s *table)
     outw(0x1206, VGAREG_SEQU_ADDRESS);
     cirrus_switch_mode_setregs(GET_GLOBAL(table->seq), VGAREG_SEQU_ADDRESS);
     cirrus_switch_mode_setregs(GET_GLOBAL(table->graph), VGAREG_GRDC_ADDRESS);
-    cirrus_switch_mode_setregs(GET_GLOBAL(table->crtc), cirrus_get_crtc());
+    cirrus_switch_mode_setregs(GET_GLOBAL(table->crtc), stdvga_get_crtc());
 
     outb(0x00, VGAREG_PEL_MASK);
     inb(VGAREG_PEL_MASK);
@@ -339,28 +346,69 @@ cirrus_switch_mode(struct cirrus_mode_s *table)
     outb(GET_GLOBAL(table->hidden_dac), VGAREG_PEL_MASK);
     outb(0xff, VGAREG_PEL_MASK);
 
-    u8 vesacolortype = GET_GLOBAL(table->vesacolortype);
-    u8 v = vgahw_get_single_palette_reg(0x10) & 0xfe;
-    if (vesacolortype == 3)
+    u8 memmodel = GET_GLOBAL(table->memmodel);
+    u8 v = stdvga_get_single_palette_reg(0x10) & 0xfe;
+    if (memmodel == MM_PLANAR)
         v |= 0x41;
-    else if (vesacolortype)
+    else if (memmodel != MM_TEXT)
         v |= 0x01;
-    vgahw_set_single_palette_reg(0x10, v);
+    stdvga_set_single_palette_reg(0x10, v);
 }
 
-void
-cirrus_set_video_mode(u8 mode)
+static u8
+cirrus_get_memsize(void)
+{
+    // get DRAM band width
+    outb(0x0f, VGAREG_SEQU_ADDRESS);
+    u8 v = inb(VGAREG_SEQU_DATA);
+    u8 x = (v >> 3) & 0x03;
+    if (x == 0x03) {
+        if (v & 0x80)
+            // 4MB
+            return 0x40;
+        // 2MB
+        return 0x20;
+    }
+    return 0x04 << x;
+}
+
+static void
+cirrus_enable_16k_granularity(void)
+{
+    outb(0x0b, VGAREG_GRDC_ADDRESS);
+    u8 v = inb(VGAREG_GRDC_DATA);
+    outb(v | 0x20, VGAREG_GRDC_DATA);
+}
+
+static void
+cirrus_clear_vram(u16 param)
+{
+    cirrus_enable_16k_granularity();
+    u8 count = cirrus_get_memsize() * 4;
+    u8 i;
+    for (i=0; i<count; i++) {
+        outw((i<<8) | 0x09, VGAREG_GRDC_ADDRESS);
+        memset16_far(SEG_GRAPH, 0, param, 16 * 1024);
+    }
+    outw(0x0009, VGAREG_GRDC_ADDRESS);
+}
+
+int
+clext_set_mode(int mode, int flags)
 {
     dprintf(1, "cirrus mode %d\n", mode);
     SET_BDA(vbe_mode, 0);
-    struct cirrus_mode_s *table_g = cirrus_get_modeentry(mode & 0x7f);
+    struct cirrus_mode_s *table_g = cirrus_get_modeentry(mode);
     if (table_g) {
-        //XXX - cirrus_set_video_mode_extended(table);
-        return;
+        cirrus_switch_mode(table_g);
+        if (!(flags & MF_NOCLEARMEM))
+            cirrus_clear_vram(0xffff);
+        SET_BDA(video_mode, mode);
+        return 0;
     }
-    table_g = cirrus_get_modeentry(0xfe);
-    cirrus_switch_mode(table_g);
+    cirrus_switch_mode(&mode_switchback);
     dprintf(1, "cirrus mode switch regular\n");
+    return stdvga_set_mode(mode, flags);
 }
 
 static int
@@ -370,12 +418,530 @@ cirrus_check(void)
     return inb(VGAREG_SEQU_DATA) == 0x12;
 }
 
+
+/****************************************************************
+ * extbios
+ ****************************************************************/
+
+static void
+cirrus_extbios_80h(struct bregs *regs)
+{
+    u16 crtc_addr = stdvga_get_crtc();
+    outb(0x27, crtc_addr);
+    u8 v = inb(crtc_addr + 1);
+    if (v == 0xa0)
+        // 5430
+        regs->ax = 0x0032;
+    else if (v == 0xb8)
+        // 5446
+        regs->ax = 0x0039;
+    else
+        regs->ax = 0x00ff;
+    regs->bx = 0x00;
+    return;
+}
+
+static void
+cirrus_extbios_81h(struct bregs *regs)
+{
+    // XXX
+    regs->ax = 0x0100;
+}
+
+static void
+cirrus_extbios_82h(struct bregs *regs)
+{
+    u16 crtc_addr = stdvga_get_crtc();
+    outb(0x27, crtc_addr);
+    regs->al = inb(crtc_addr + 1) & 0x03;
+    regs->ah = 0xAF;
+}
+
+static void
+cirrus_extbios_85h(struct bregs *regs)
+{
+    regs->al = cirrus_get_memsize();
+}
+
+static void
+cirrus_extbios_9Ah(struct bregs *regs)
+{
+    regs->ax = 0x4060;
+    regs->cx = 0x1132;
+}
+
+extern void a0h_callback(void);
+ASM16(
+    // fatal: not implemented yet
+    "a0h_callback:"
+    "cli\n"
+    "hlt\n"
+    "retf");
+
+static void
+cirrus_extbios_A0h(struct bregs *regs)
+{
+    struct cirrus_mode_s *table_g = cirrus_get_modeentry(regs->al & 0x7f);
+    regs->ah = (table_g ? 1 : 0);
+    regs->si = 0xffff;
+    regs->di = regs->ds = regs->es = regs->bx = (u32)a0h_callback;
+}
+
+static void
+cirrus_extbios_A1h(struct bregs *regs)
+{
+    regs->bx = 0x0e00; // IBM 8512/8513, color
+}
+
+static void
+cirrus_extbios_A2h(struct bregs *regs)
+{
+    regs->al = 0x07; // HSync 31.5 - 64.0 kHz
+}
+
+static void
+cirrus_extbios_AEh(struct bregs *regs)
+{
+    regs->al = 0x01; // High Refresh 75Hz
+}
+
 void
-cirrus_init(void)
+cirrus_extbios(struct bregs *regs)
+{
+    // XXX - regs->bl < 0x80 or > 0xaf call regular handlers.
+    switch (regs->bl) {
+    case 0x80: cirrus_extbios_80h(regs); break;
+    case 0x81: cirrus_extbios_81h(regs); break;
+    case 0x82: cirrus_extbios_82h(regs); break;
+    case 0x85: cirrus_extbios_85h(regs); break;
+    case 0x9a: cirrus_extbios_9Ah(regs); break;
+    case 0xa0: cirrus_extbios_A0h(regs); break;
+    case 0xa1: cirrus_extbios_A1h(regs); break;
+    case 0xa2: cirrus_extbios_A2h(regs); break;
+    case 0xae: cirrus_extbios_AEh(regs); break;
+    default: break;
+    }
+}
+
+
+/****************************************************************
+ * vesa calls
+ ****************************************************************/
+
+static struct {
+    u16 vesamode, mode;
+} cirrus_vesa_modelist[] VAR16 = {
+    // 640x480x8
+    { 0x101, 0x5f },
+    // 640x480x15
+    { 0x110, 0x66 },
+    // 640x480x16
+    { 0x111, 0x64 },
+    // 640x480x24
+    { 0x112, 0x71 },
+    // 800x600x8
+    { 0x103, 0x5c },
+    // 800x600x15
+    { 0x113, 0x67 },
+    // 800x600x16
+    { 0x114, 0x65 },
+    // 800x600x24
+    { 0x115, 0x78 },
+    // 1024x768x8
+    { 0x105, 0x60 },
+    // 1024x768x15
+    { 0x116, 0x68 },
+    // 1024x768x16
+    { 0x117, 0x74 },
+    // 1024x768x24
+    { 0x118, 0x79 },
+    // 1280x1024x8
+    { 0x107, 0x6d },
+    // 1280x1024x15
+    { 0x119, 0x69 },
+    // 1280x1024x16
+    { 0x11a, 0x75 },
+};
+
+static u16
+cirrus_vesamode_to_mode(u16 vesamode)
+{
+    int i;
+    for (i=0; i<ARRAY_SIZE(cirrus_vesa_modelist); i++)
+        if (GET_GLOBAL(cirrus_vesa_modelist[i].vesamode) == vesamode)
+            return GET_GLOBAL(cirrus_vesa_modelist[i].mode);
+    return 0;
+}
+
+static u8
+cirrus_get_bpp_bytes(void)
+{
+    outb(0x07, VGAREG_SEQU_ADDRESS);
+    u8 v = inb(VGAREG_SEQU_DATA) & 0x0e;
+    if (v == 0x06)
+        v &= 0x02;
+    v >>= 1;
+    if (v != 0x04)
+        v++;
+    return v;
+}
+
+static void
+cirrus_set_line_offset(u16 new_line_offset)
+{
+    u16 crtc_addr = stdvga_get_crtc();
+    outb(0x13, crtc_addr);
+    outb(new_line_offset / 8, crtc_addr + 1);
+
+    outb(0x1b, crtc_addr);
+    u8 v = inb(crtc_addr + 1);
+    outb((((new_line_offset / 8) & 0x100) >> 4) | (v & 0xef), crtc_addr + 1);
+}
+
+static u16
+cirrus_get_line_offset(void)
+{
+    u16 crtc_addr = stdvga_get_crtc();
+    outb(0x13, crtc_addr);
+    u8 reg13 = inb(crtc_addr + 1);
+    outb(0x1b, crtc_addr);
+    u8 reg1b = inb(crtc_addr + 1);
+
+    return (((reg1b << 4) & 0x100) + reg13) * 8;
+}
+
+static u16
+cirrus_get_line_offset_entry(struct cirrus_mode_s *table_g)
+{
+    u16 *crtc = GET_GLOBAL(table_g->crtc);
+
+    u16 *c = crtc;
+    u16 reg13;
+    for (;;) {
+        reg13 = GET_GLOBAL(*c);
+        if ((reg13 & 0xff) == 0x13)
+            break;
+        c++;
+    }
+    reg13 >>= 8;
+
+    c = crtc;
+    u16 reg1b;
+    for (;;) {
+        reg1b = GET_GLOBAL(*c);
+        if ((reg1b & 0xff) == 0x1b)
+            break;
+        c++;
+    }
+    reg1b >>= 8;
+
+    return (((reg1b << 4) & 0x100) + reg13) * 8;
+}
+
+static void
+cirrus_set_start_addr(u32 addr)
 {
+    u16 crtc_addr = stdvga_get_crtc();
+    outb(0x0d, crtc_addr);
+    outb(addr, crtc_addr + 1);
+
+    outb(0x0c, crtc_addr);
+    outb(addr>>8, crtc_addr + 1);
+
+    outb(0x1d, crtc_addr);
+    u8 v = inb(crtc_addr + 1);
+    outb(((addr & 0x0800) >> 4) | (v & 0x7f), crtc_addr + 1);
+
+    outb(0x1b, crtc_addr);
+    v = inb(crtc_addr + 1);
+    outb(((addr & 0x0100) >> 8) | ((addr & 0x0600) >> 7) | (v & 0xf2)
+         , crtc_addr + 1);
+}
+
+static u32
+cirrus_get_start_addr(void)
+{
+    u16 crtc_addr = stdvga_get_crtc();
+    outb(0x0c, crtc_addr);
+    u8 b2 = inb(crtc_addr + 1);
+
+    outb(0x0d, crtc_addr);
+    u8 b1 = inb(crtc_addr + 1);
+
+    outb(0x1b, crtc_addr);
+    u8 b3 = inb(crtc_addr + 1);
+
+    outb(0x1d, crtc_addr);
+    u8 b4 = inb(crtc_addr + 1);
+
+    return (b1 | (b2<<8) | ((b3 & 0x01) << 16) | ((b3 & 0x0c) << 15)
+            | ((b4 & 0x80) << 12));
+}
+
+static void
+cirrus_vesa_00h(struct bregs *regs)
+{
+    u16 seg = regs->es;
+    struct vbe_info *info = (void*)(regs->di+0);
+
+    if (GET_FARVAR(seg, info->signature) == VBE2_SIGNATURE) {
+        SET_FARVAR(seg, info->oem_revision, 0x0100);
+        SET_FARVAR(seg, info->oem_vendor_string,
+                   SEGOFF(get_global_seg(), (u32)VBE_VENDOR_STRING));
+        SET_FARVAR(seg, info->oem_product_string,
+                   SEGOFF(get_global_seg(), (u32)VBE_PRODUCT_STRING));
+        SET_FARVAR(seg, info->oem_revision_string,
+                   SEGOFF(get_global_seg(), (u32)VBE_REVISION_STRING));
+    }
+    SET_FARVAR(seg, info->signature, VESA_SIGNATURE);
+
+    SET_FARVAR(seg, info->version, 0x0200);
+
+    SET_FARVAR(seg, info->oem_string
+               , SEGOFF(get_global_seg(), (u32)VBE_OEM_STRING));
+    SET_FARVAR(seg, info->capabilities, 0);
+    SET_FARVAR(seg, info->total_memory, cirrus_get_memsize());
+
+    u16 *destmode = (void*)info->reserved;
+    SET_FARVAR(seg, info->video_mode, SEGOFF(seg, (u32)destmode));
+    int i;
+    for (i=0; i<ARRAY_SIZE(cirrus_vesa_modelist); i++)
+        SET_FARVAR(seg, destmode[i]
+                   , GET_GLOBAL(cirrus_vesa_modelist[i].vesamode));
+    SET_FARVAR(seg, destmode[i], 0xffff);
+
+    regs->ax = 0x004f;
+}
+
+static u32 cirrus_lfb_addr VAR16;
+
+static void
+cirrus_vesa_01h(struct bregs *regs)
+{
+    u16 mode = cirrus_vesamode_to_mode(regs->cx & 0x3fff);
+    if (!mode) {
+        regs->ax = 0x014f;
+        return;
+    }
+    struct cirrus_mode_s *table_g = cirrus_get_modeentry(mode);
+    u32 lfb = GET_GLOBAL(cirrus_lfb_addr); // XXX
+    if ((regs->cx & 0x4000) && !lfb) {
+        regs->ax = 0x014f;
+        return;
+    }
+
+    u16 seg = regs->es;
+    struct vbe_mode_info *info = (void*)(regs->di+0);
+    memset_far(seg, info, 0, sizeof(*info));
+
+    SET_FARVAR(seg, info->mode_attributes, lfb ? 0xbb : 0x3b);
+    SET_FARVAR(seg, info->winA_attributes, 0x07);
+    SET_FARVAR(seg, info->winB_attributes, 0);
+    SET_FARVAR(seg, info->win_granularity, 16);
+    SET_FARVAR(seg, info->win_size, 64);
+    SET_FARVAR(seg, info->winA_seg, SEG_GRAPH);
+    SET_FARVAR(seg, info->winB_seg, 0x0);
+    SET_FARVAR(seg, info->win_func_ptr.segoff, 0x0); // XXX
+    u16 linesize = cirrus_get_line_offset_entry(table_g);
+    SET_FARVAR(seg, info->bytes_per_scanline, linesize);
+    SET_FARVAR(seg, info->xres, GET_GLOBAL(table_g->width));
+    u16 height = GET_GLOBAL(table_g->height);
+    SET_FARVAR(seg, info->yres, height);
+    SET_FARVAR(seg, info->xcharsize, 8);
+    SET_FARVAR(seg, info->ycharsize, 16);
+    SET_FARVAR(seg, info->planes, 1);
+    SET_FARVAR(seg, info->bits_per_pixel, GET_GLOBAL(table_g->depth));
+    SET_FARVAR(seg, info->banks, 1);
+    SET_FARVAR(seg, info->mem_model, GET_GLOBAL(table_g->memmodel));
+    SET_FARVAR(seg, info->bank_size, 0);
+
+    int pages = (cirrus_get_memsize() * 64 * 1024) / (height * linesize);
+    SET_FARVAR(seg, info->pages, pages - 1);
+    SET_FARVAR(seg, info->reserved0, 0);
+
+    SET_FARVAR(seg, info->red_size, GET_GLOBAL(table_g->vesaredmask));
+    SET_FARVAR(seg, info->red_pos, GET_GLOBAL(table_g->vesaredpos));
+    SET_FARVAR(seg, info->green_size, GET_GLOBAL(table_g->vesagreenmask));
+    SET_FARVAR(seg, info->green_pos, GET_GLOBAL(table_g->vesagreenpos));
+    SET_FARVAR(seg, info->blue_size, GET_GLOBAL(table_g->vesabluemask));
+    SET_FARVAR(seg, info->blue_pos, GET_GLOBAL(table_g->vesabluepos));
+    SET_FARVAR(seg, info->alpha_size, GET_GLOBAL(table_g->vesareservedmask));
+    SET_FARVAR(seg, info->alpha_pos, GET_GLOBAL(table_g->vesareservedpos));
+    u8 directcolor_info = GET_GLOBAL(table_g->bitsperpixel) <= 8;
+    SET_FARVAR(seg, info->directcolor_info, directcolor_info);
+
+    SET_FARVAR(seg, info->phys_base, lfb);
+
+    regs->ax = 0x004f;
+}
+
+static void
+cirrus_vesa_02h(struct bregs *regs)
+{
+    if (regs->bx & 0x3e00) {
+        regs->ax = 0x014f;
+        return;
+    }
+    if ((regs->bx & 0x1ff) < 0x100) {
+        // XXX - call legacy mode switch
+        regs->ax = 0x004f;
+        return;
+    }
+
+    u16 mode = cirrus_vesamode_to_mode(regs->cx & 0x3fff);
+    if (!mode) {
+        regs->ax = 0x014f;
+        return;
+    }
+    struct cirrus_mode_s *table_g = cirrus_get_modeentry(mode);
+    cirrus_switch_mode(table_g);
+
+    if (!(regs->bx & 0x4000))
+        cirrus_enable_16k_granularity();
+    if (!(regs->bx & 0x8000))
+        cirrus_clear_vram(0);
+    SET_BDA(video_mode, mode);
+    SET_BDA(vbe_mode, regs->bx);
+
+    regs->ax = 0x004f;
+}
+
+static void
+cirrus_vesa_03h(struct bregs *regs)
+{
+    u16 mode = GET_BDA(vbe_mode);
+    if (!mode)
+        mode = GET_BDA(video_mode);
+    regs->bx = mode;
+
+    regs->ax = 0x004f;
+}
+
+// XXX - add cirrus_vesa_05h_farentry to vgaentry.S
+
+static void
+cirrus_vesa_05h(struct bregs *regs)
+{
+    if (regs->bl > 1)
+        goto fail;
+    if (regs->bh == 0) {
+        // set mempage
+        if (regs->dx >= 0x100)
+            goto fail;
+        outw((regs->dx << 8) | (regs->bl + 9), VGAREG_GRDC_ADDRESS);
+    } else if (regs->bh == 1) {
+        // get mempage
+        outb(regs->bl + 9, VGAREG_GRDC_ADDRESS);
+        regs->dx = inb(VGAREG_GRDC_DATA);
+    } else
+        goto fail;
+
+    regs->ax = 0x004f;
+    return;
+fail:
+    regs->ax = 0x014f;
+}
+
+static void
+cirrus_vesa_06h(struct bregs *regs)
+{
+    if (regs->bl > 2) {
+        regs->ax = 0x0100;
+        return;
+    }
+
+    if (regs->bl == 0x00) {
+        cirrus_set_line_offset(cirrus_get_bpp_bytes() * regs->cx);
+    } else if (regs->bl == 0x02) {
+        cirrus_set_line_offset(regs->cx);
+    }
+
+    u32 v = cirrus_get_line_offset();
+    regs->cx = v / cirrus_get_bpp_bytes();
+    regs->bx = v;
+    regs->dx = (cirrus_get_memsize() * 64 * 1024) / v;
+    regs->ax = 0x004f;
+}
+
+static void
+cirrus_vesa_07h(struct bregs *regs)
+{
+    if (regs->bl == 0x80 || regs->bl == 0x00) {
+        u32 addr = (cirrus_get_bpp_bytes() * regs->cx
+                    + cirrus_get_line_offset() * regs->dx);
+        cirrus_set_start_addr(addr / 4);
+    } else if (regs->bl == 0x01) {
+        u32 addr = cirrus_get_start_addr() * 4;
+        u32 linelength = cirrus_get_line_offset();
+        regs->dx = addr / linelength;
+        regs->cx = (addr % linelength) / cirrus_get_bpp_bytes();
+    } else {
+        regs->ax = 0x0100;
+        return;
+    }
+
+    regs->ax = 0x004f;
+}
+
+static void
+cirrus_vesa_10h(struct bregs *regs)
+{
+    if (regs->bl == 0x00) {
+        regs->bx = 0x0f30;
+        regs->ax = 0x004f;
+        return;
+    }
+    if (regs->bl == 0x01) {
+        SET_BDA(vbe_flag, regs->bh);
+        regs->ax = 0x004f;
+        return;
+    }
+    if (regs->bl == 0x02) {
+        regs->bh = GET_BDA(vbe_flag);
+        regs->ax = 0x004f;
+        return;
+    }
+    regs->ax = 0x014f;
+}
+
+static void
+cirrus_vesa_not_handled(struct bregs *regs)
+{
+    debug_stub(regs);
+    regs->ax = 0x014f;
+}
+
+void
+cirrus_vesa(struct bregs *regs)
+{
+    switch (regs->al) {
+    case 0x00: cirrus_vesa_00h(regs); break;
+    case 0x01: cirrus_vesa_01h(regs); break;
+    case 0x02: cirrus_vesa_02h(regs); break;
+    case 0x03: cirrus_vesa_03h(regs); break;
+    case 0x05: cirrus_vesa_05h(regs); break;
+    case 0x06: cirrus_vesa_06h(regs); break;
+    case 0x07: cirrus_vesa_07h(regs); break;
+    case 0x10: cirrus_vesa_10h(regs); break;
+    default:   cirrus_vesa_not_handled(regs); break;
+    }
+}
+
+
+/****************************************************************
+ * init
+ ****************************************************************/
+
+int
+clext_init(void)
+{
+    int ret = stdvga_init();
+    if (ret)
+        return ret;
+
     dprintf(1, "cirrus init\n");
     if (! cirrus_check())
-        return;
+        return -1;
     dprintf(1, "cirrus init 2\n");
 
     // memory setup
@@ -387,4 +953,6 @@ cirrus_init(void)
     // reset bitblt
     outw(0x0431, VGAREG_GRDC_ADDRESS);
     outw(0x0031, VGAREG_GRDC_ADDRESS);
+
+    return 0;
 }