tools/kvm/bios/int10.c

   1 #include "kvm/segment.h"
   2 #include "kvm/bios.h"
   3 #include "kvm/util.h"
   4 #include "kvm/vesa.h"
   5 #include <stdint.h>
   6
   7 #define VESA_MAGIC ('V' + ('E' << 8) + ('S' << 16) + ('A' << 24))
   8
   9 /* VESA General Information table */
  10 struct vesa_general_info {
  11         u32     signature;              /* 0 Magic number = "VESA" */
  12         u16     version;                /* 4 */
  13         void    *vendor_string;         /* 6 */
  14         u32     capabilities;           /* 10 */
  15         void    *video_mode_ptr;        /* 14 */
  16         u16     total_memory;           /* 18 */
  17         u16     modes[2];               /* 20 */
  18         char    oem_string[11];         /* 24 */
  19
  20         u8      reserved[223];          /* 35 */
  21 } __attribute__ ((packed));
  22
  23 struct vminfo {
  24         u16     mode_attr;              /* 0 */
  25         u8      win_attr[2];            /* 2 */
  26         u16     win_grain;              /* 4 */
  27         u16     win_size;               /* 6 */
  28         u16     win_seg[2];             /* 8 */
  29         u32     win_scheme;             /* 12 */
  30         u16     logical_scan;           /* 16 */
  31
  32         u16     h_res;                  /* 18 */
  33         u16     v_res;                  /* 20 */
  34         u8      char_width;             /* 22 */
  35         u8      char_height;            /* 23 */
  36         u8      memory_planes;          /* 24 */
  37         u8      bpp;                    /* 25 */
  38         u8      banks;                  /* 26 */
  39         u8      memory_layout;          /* 27 */
  40         u8      bank_size;              /* 28 */
  41         u8      image_planes;           /* 29 */
  42         u8      page_function;          /* 30 */
  43
  44         u8      rmask;                  /* 31 */
  45         u8      rpos;                   /* 32 */
  46         u8      gmask;                  /* 33 */
  47         u8      gpos;                   /* 34 */
  48         u8      bmask;                  /* 35 */
  49         u8      bpos;                   /* 36 */
  50         u8      resv_mask;              /* 37 */
  51         u8      resv_pos;               /* 38 */
  52         u8      dcm_info;               /* 39 */
  53
  54         u32     lfb_ptr;                /* 40 Linear frame buffer address */
  55         u32     offscreen_ptr;          /* 44 Offscreen memory address */
  56         u16     offscreen_size;         /* 48 */
  57
  58         u8      reserved[206];          /* 50 */
  59 };
  60
  61 static inline void outb(unsigned short port, unsigned char val)
  62 {
  63         asm volatile("outb %0, %1" : : "a"(val), "Nd"(port));
  64 }
  65
  66 /*
  67  * It's probably much more useful to make this print to the serial
  68  * line rather than print to a non-displayed VGA memory
  69  */
  70 static inline void int10_putchar(struct biosregs *args)
  71 {
  72         u8 al = args->eax & 0xFF;
  73
  74         outb(0x3f8, al);
  75 }
  76
  77 static void vbe_get_mode(struct biosregs *args)
  78 {
  79         struct vminfo *info = (struct vminfo *) args->edi;
  80
  81         *info = (struct vminfo) {
  82                 .mode_attr              = 0xd9, /* 11011011 */
  83                 .logical_scan           = VESA_WIDTH*4,
  84                 .h_res                  = VESA_WIDTH,
  85                 .v_res                  = VESA_HEIGHT,
  86                 .bpp                    = VESA_BPP,
  87                 .memory_layout          = 6,
  88                 .memory_planes          = 1,
  89                 .lfb_ptr                = VESA_MEM_ADDR,
  90                 .rmask                  = 8,
  91                 .gmask                  = 8,
  92                 .bmask                  = 8,
  93                 .resv_mask              = 8,
  94                 .resv_pos               = 24,
  95                 .bpos                   = 16,
  96                 .gpos                   = 8,
  97         };
  98 }
  99
 100 static void vbe_get_info(struct biosregs *args)
 101 {
 102         struct vesa_general_info *info = (struct vesa_general_info *) args->edi;
 103
 104         *info = (struct vesa_general_info) {
 105                 .signature              = VESA_MAGIC,
 106                 .version                = 0x102,
 107                 .vendor_string          = &info->oem_string,
 108                 .capabilities           = 0x10,
 109                 .video_mode_ptr         = &info->modes,
 110                 .total_memory           = (4 * VESA_WIDTH * VESA_HEIGHT) / 0x10000,
 111                 .oem_string             = "KVM VESA",
 112                 .modes                  = { 0x0112, 0xffff },
 113         };
 114 }
 115
 116 #define VBE_STATUS_OK           0x004F
 117
 118 static void int10_vesa(struct biosregs *args)
 119 {
 120         u8 al;
 121
 122         al = args->eax & 0xff;
 123
 124         switch (al) {
 125         case 0x00:
 126                 vbe_get_info(args);
 127                 break;
 128         case 0x01:
 129                 vbe_get_mode(args);
 130                 break;
 131         }
 132
 133         args->eax = VBE_STATUS_OK;
 134 }
 135
 136 bioscall void int10_handler(struct biosregs *args)
 137 {
 138         u8 ah;
 139
 140         ah = (args->eax & 0xff00) >> 8;
 141
 142         switch (ah) {
 143         case 0x0e:
 144                 int10_putchar(args);
 145                 break;
 146         case 0x4f:
 147                 int10_vesa(args);
 148                 break;
 149         }
 150
 151 }