- new function dispi_get_max_bpp() returns the bpp capabilities of the Bochs gui

- create the mode list depending on the supported bpp capability
- unused stuff removed
- documentation updated

4 files changed, 48 insertions, 28 deletions

diff --git a/README b/README
index 872b5ad..b9dd40b 100644
--- a/README
+++ b/README
@@ -97,12 +97,12 @@ vgabios-0.4b : Nov 04 2003
 
 vgabios-0.4a : Aug 17 2003
   - Volker
-    . LFB flagged VBE modes removed
+    . VBE mode search rewritten (VBE modes with LFB bit removed)
     . many bugfixes and optimizations
-    . write character function implemeted for graphic modes
+    . write character function implemented for graphics modes
     . support for 15bpp, 16bpp, 24bpp and 32bpp VBE modes added
-    . SVGA modes 0x6A added
-    . VBE mode 0x102, 0x117, 0x118, 0x142 (Bochs specific)
+    . SVGA mode 0x6A added
+    . VBE modes 0x102, 0x117, 0x118 and 0x142 (Bochs specific)
 
 vgabios-0.3b : Nov 23 2002
   - Christophe
diff --git a/vbe.c b/vbe.c
index efedcb0..c8e4066 100644
--- a/vbe.c
+++ b/vbe.c
@@ -47,16 +47,11 @@
 // The current OEM Software Revision of this VBE Bios
 #define VBE_OEM_SOFTWARE_REV 0x0002;
 
-#define VBEInfoData ((VbeInfoBlock *) 0)
-
 extern char vbebios_copyright;
 extern char vbebios_vendor_name;
 extern char vbebios_product_name;
 extern char vbebios_product_revision;
 
-// FIXME: find out why we cannot use the dynamic list generation (due to a bug somewhere)
-//#define DYN_LIST
-
 #ifndef DYN_LIST
 extern Bit16u vbebios_mode_list;
 #endif
@@ -178,6 +173,19 @@ static Bit16u dispi_get_bpp()
   return inw(VBE_DISPI_IOPORT_DATA);
 }
 
+static Bit16u dispi_get_max_bpp()
+{
+  Bit16u max_bpp;
+
+  outw(VBE_DISPI_IOPORT_INDEX,VBE_DISPI_INDEX_ENABLE);
+  outw(VBE_DISPI_IOPORT_DATA,VBE_DISPI_GETCAPS);
+  outw(VBE_DISPI_IOPORT_INDEX,VBE_DISPI_INDEX_BPP);
+  max_bpp = inw(VBE_DISPI_IOPORT_DATA);
+  outw(VBE_DISPI_IOPORT_INDEX,VBE_DISPI_INDEX_ENABLE);
+  outw(VBE_DISPI_IOPORT_DATA,VBE_DISPI_DISABLED);
+  return max_bpp;
+}
+
 static Bit16u dispi_get_enable()
 {
   outw(VBE_DISPI_IOPORT_INDEX,VBE_DISPI_INDEX_ENABLE);
@@ -342,7 +350,7 @@ void vbe_init()
   if (dispi_id==VBE_DISPI_ID0)
   {
     write_byte(BIOSMEM_SEG,BIOSMEM_VBE_FLAG,0x01);
-    dispi_set_id(VBE_DISPI_ID2);
+    dispi_set_id(VBE_DISPI_ID3);
   }
   printf("VBE Bios $Id$\n");
 }
@@ -481,14 +489,15 @@ Bit16u *AX;Bit16u ES;Bit16u DI;
 #ifdef DYN_LIST
         do
         {
+                if (cur_info->info.BitsPerPixel <= dispi_get_max_bpp()) {
 #ifdef DEBUG
-                printf("VBE found mode %x => %x\n", cur_info->mode,cur_mode);
+                  printf("VBE found mode %x => %x\n", cur_info->mode,cur_mode);
 #endif
-                write_word(ES, DI + cur_ptr, cur_info->mode);
-
+                  write_word(ES, DI + cur_ptr, cur_info->mode);
+                  cur_mode++;
+                  cur_ptr+=2;
+                }
                 cur_info++;
-                cur_mode++;
-                cur_ptr+=2;
         } while (cur_info->mode != VBE_VESA_MODE_END_OF_LIST);
         
         // Add vesa mode list terminator
diff --git a/vbe.h b/vbe.h
index 4ed03c6..b79c9e0 100644
--- a/vbe.h
+++ b/vbe.h
@@ -292,9 +292,11 @@ typedef struct ModeInfoBlock
   #define VBE_DISPI_ID0                   0xB0C0
   #define VBE_DISPI_ID1                   0xB0C1
   #define VBE_DISPI_ID2                   0xB0C2
+  #define VBE_DISPI_ID3                   0xB0C3
   
   #define VBE_DISPI_DISABLED              0x00
   #define VBE_DISPI_ENABLED               0x01
+  #define VBE_DISPI_GETCAPS               0x02
   #define VBE_DISPI_LFB_ENABLED           0x40
   #define VBE_DISPI_NOCLEARMEM            0x80
   
diff --git a/vbe_display_api.txt b/vbe_display_api.txt
index 787dc31..86322b4 100644
--- a/vbe_display_api.txt
+++ b/vbe_display_api.txt
@@ -30,12 +30,16 @@ API History
                   VBE_DISPI_INDEX_X_OFFSET
                   VBE_DISPI_INDEX_Y_OFFSET
 
-0xb0c2            supports 0xb0c1 VBE_DISPI_ interfaces, interfaces updated for additional features:
+0xb0c2            supports 0xb0c1 VBE_DISPI_ interfaces, interfaces updated for
+                  additional features (present in Bochs 2.1):
                   VBE_DISPI_INDEX_BPP supports >8bpp color depth (value = bits)
                   VBE_DISPI_INDEX_ENABLE supports new flags VBE_DISPI_NOCLEARMEM and VBE_DISPI_LFB_ENABLED
                   VBE i/o registers changed from 0xFF80/81 to 0x01CE/CF
 
-                  
+0xb0c3            supports 0xb0c2 VBE_DISPI_ interfaces, interfaces updated for
+                  additional features:
+                  VBE_DISPI_INDEX_ENABLE supports new flag VBE_DISPI_GETCAPS
+
 
 History
 -------
@@ -195,26 +199,31 @@ API
     The new flag VBE_DISPI_NOCLEARMEM allows to preserve the VBE video memory.
     The new flag VBE_DISPI_LFB_ENABLED indicates the usage of the LFB.
 
-Displaying GFX
+[0xb0c3]
+  * VBE_DISPI_INDEX_ENABLE : WORD {R,W}
+    If the new flag VBE_DISPI_GETCAPS is enabled, the xres, yres and bpp registers
+    return the gui capabilities.
+
+Displaying GFX (banked mode)
 --------------
-  Currently Linear Frame Buffer support is not available yet.
-  The only other way of displaying (VBE) graphics is using banked modi.
-  
   What happens is that the total screen is devided in banks of 'VBE_DISPI_BANK_SIZE_KB' KiloByte in size.
   If you want to set a pixel you can calculate its bank by doing:
-  
+
     offset = pixel_x + pixel_y * resolution_x;
     bank = offset / 64 Kb (rounded 1.9999 -> 1)
-    
+
     bank_pixel_pos = offset - bank * 64Kb
-    
-  Now you can set the current bank and put the pixel at VBE_DISPI_BANK_ADDRESS + bank_pixel_pos  
 
+  Now you can set the current bank and put the pixel at VBE_DISPI_BANK_ADDRESS + bank_pixel_pos
+
+Displaying GFX (linear frame buffer mode)
+--------------
+  NOT WRITTEN YET
 
 Notes
 ----- 
   * Since the XRES/YRES/BPP may not be written when VBE is enabled, if you want to switch from one VBE mode
     to another, you will need to disable VBE first.
-  
-  * Note when the bios doesn't find a valid DISPI_ID, it can disable the VBE functions. This allows people to 
-    use the same bios for both vbe enabled and disabled bochs executables.
\ No newline at end of file
+
+  * Note when the bios doesn't find a valid DISPI_ID, it can disable the VBE functions. This allows people to
+    use the same bios for both vbe enabled and disabled bochs executables.