OvmfPkg/Bhyve/BhyveRfbDxe/VbeShim.asm

   1 ;------------------------------------------------------------------------------
   2 ; @file
   3 ; A minimal Int10h stub that allows the Windows 2008 R2 SP1 UEFI guest's buggy,
   4 ; default VGA driver to switch to 1024x768x32.
   5 ;
   6 ; Copyright (C) 2020, Rebecca Cran <rebecca@bsdio.com>
   7 ; Copyright (C) 2015, Nahanni Systems, Inc.
   8 ; Copyright (C) 2014, Red Hat, Inc.
   9 ; Copyright (c) 2013 - 2014, Intel Corporation. All rights reserved.<BR>
  10 ;
  11 ; SPDX-License-Identifier: BSD-2-Clause-Patent
  12 ;
  13 ;------------------------------------------------------------------------------
  14
  15 ; enable this macro for debug messages
  16 %define DEBUG
  17
  18 %macro DebugLog 1
  19 %ifdef DEBUG
  20   push       si
  21   mov        si, %1
  22   call       PrintStringSi
  23   pop        si
  24 %endif
  25 %endmacro
  26
  27
  28 BITS 16
  29 ORG 0
  30
  31 VbeInfo:
  32 TIMES 256 nop
  33
  34 VbeModeInfo:
  35 VbeMode1:
  36 TIMES 50  nop
  37 VbeMode2:
  38 TIMES 50  nop
  39 VbeMode3:
  40 TIMES 50  nop
  41 VbeMode4:
  42 TIMES 50  nop
  43 TIMES 56  nop  ; filler for 256 bytes
  44
  45 Handler:
  46   cmp        ax, 0x4f00
  47   je         GetInfo
  48   cmp        ax, 0x4f01
  49   je         GetModeInfo
  50   cmp        ax, 0x4f02
  51   je         SetMode
  52   cmp        ax, 0x4f03
  53   je         GetMode
  54   cmp        ax, 0x4f10
  55   je         GetPmCapabilities
  56   cmp        ax, 0x4f15
  57   je         ReadEdid
  58   cmp        ah, 0x00
  59   je         SetModeLegacy
  60   DebugLog   StrUnkownFunction
  61 Hang:
  62   jmp        Hang
  63
  64
  65 GetInfo:
  66   push       es
  67   push       di
  68   push       ds
  69   push       si
  70   push       cx
  71
  72   DebugLog   StrEnterGetInfo
  73
  74   ; target (es:di) set on input
  75   push       cs
  76   pop        ds
  77   mov        si, VbeInfo
  78   ; source (ds:si) set now
  79
  80   mov        cx, 256
  81   cld
  82   rep movsb
  83
  84   pop        cx
  85   pop        si
  86   pop        ds
  87   pop        di
  88   pop        es
  89   jmp        Success
  90
  91
  92 GetModeInfo:
  93   push       es
  94   push       di
  95   push       ds
  96   push       si
  97   push       cx
  98
  99   DebugLog   StrEnterGetModeInfo
 100
 101   and        cx, ~0x4000 ; clear potentially set LFB bit in mode number
 102
 103   cmp        cx, 0x013f
 104   je         gKnownMode1
 105   cmp        cx, 0x0140
 106   je         gKnownMode2
 107   cmp        cx, 0x0141
 108   je         gKnownMode3
 109
 110   DebugLog   StrUnkownMode
 111   jmp        Hang
 112 gKnownMode1:
 113   DebugLog   StrMode1
 114   mov        si, VbeMode1
 115   jmp        CopyModeInfo
 116 gKnownMode2:
 117   DebugLog   StrMode2
 118   mov        si, VbeMode2
 119   jmp        CopyModeInfo
 120 gKnownMode3:
 121   DebugLog   StrMode3
 122   mov        si, VbeMode3
 123   jmp        CopyModeInfo
 124 gKnownMode4:
 125   DebugLog   StrMode4
 126   mov        si, VbeMode4
 127   jmp        CopyModeInfo
 128
 129 CopyModeInfo:
 130   ; target (es:di) set on input
 131   push       cs
 132   pop        ds
 133   ;mov        si, VbeModeInfo
 134   ; source (ds:si) set now
 135
 136   ;mov        cx, 256
 137   mov        cx, 50
 138   cld
 139   rep movsb
 140
 141   pop        cx
 142   pop        si
 143   pop        ds
 144   pop        di
 145   pop        es
 146   jmp        Success
 147
 148
 149 SetMode:
 150   push       dx
 151   push       ax
 152
 153   DebugLog   StrEnterSetMode
 154
 155   and        bx, ~0x4000 ; clear potentially set LFB bit in mode number
 156   cmp        bx, 0x013f
 157   je         KnownMode1
 158   cmp        bx, 0x0140
 159   je         KnownMode2
 160   cmp        bx, 0x0141
 161   je         KnownMode3
 162   DebugLog   StrUnkownMode
 163   jmp        Hang
 164 KnownMode1:
 165   DebugLog   StrMode1
 166   jmp        SetModeDone
 167 KnownMode2:
 168   DebugLog   StrMode2
 169   jmp        SetModeDone
 170 KnownMode3:
 171   DebugLog   StrMode3
 172   jmp        SetModeDone
 173 KnownMode4:
 174   DebugLog   StrMode4
 175
 176 SetModeDone:
 177   mov        [CurMode], bl
 178   mov        [CurMode+1], bh
 179   pop        ax
 180   pop        dx
 181   jmp        Success
 182
 183
 184 GetMode:
 185   DebugLog   StrEnterGetMode
 186   mov        bl, [CurMode]
 187   mov        bh, [CurMode+1]
 188   jmp        Success
 189
 190
 191 GetPmCapabilities:
 192   DebugLog   StrGetPmCapabilities
 193   mov        bx, 0x0080
 194   jmp        Success
 195
 196
 197 ReadEdid:
 198   push       es
 199   push       di
 200   push       ds
 201   push       si
 202   push       cx
 203
 204   DebugLog   StrReadEdid
 205
 206   ; target (es:di) set on input
 207   push       cs
 208   pop        ds
 209   mov        si, Edid
 210   ; source (ds:si) set now
 211
 212   mov        cx, 128
 213   cld
 214   rep movsb
 215
 216   pop        cx
 217   pop        si
 218   pop        ds
 219   pop        di
 220   pop        es
 221   jmp        Success
 222
 223
 224 SetModeLegacy:
 225   DebugLog   StrEnterSetModeLegacy
 226
 227   cmp        al, 0x03
 228   je         sKnownMode3
 229   cmp        al, 0x12
 230   je         sKnownMode4
 231   DebugLog   StrUnkownMode
 232   jmp        Hang
 233 sKnownMode3:
 234   DebugLog   StrLegacyMode3
 235   mov        al, 0 ; 0x30
 236   jmp        SetModeLegacyDone
 237 sKnownMode4:
 238   mov        al, 0 ;0x20
 239 SetModeLegacyDone:
 240   DebugLog   StrExitSuccess
 241   iret
 242
 243
 244 Success:
 245   DebugLog   StrExitSuccess
 246   mov        ax, 0x004f
 247   iret
 248
 249
 250 Unsupported:
 251   DebugLog   StrExitUnsupported
 252   mov        ax, 0x024f
 253   iret
 254
 255
 256 %ifdef DEBUG
 257 PrintStringSi:
 258   pusha
 259   push       ds ; save original
 260   push       cs
 261   pop        ds
 262   mov        dx, 0x220             ; bhyve debug cons port
 263   mov        ax, 0
 264 PrintStringSiLoop:
 265   lodsb
 266   cmp        al, 0
 267   je         PrintStringSiDone
 268   out        dx, al
 269   jmp        PrintStringSiLoop
 270 PrintStringSiDone:
 271   pop        ds ; restore original
 272   popa
 273   ret
 274
 275
 276 StrExitSuccess:
 277   db 'vOk', 0x0d, 0x0a, 0
 278
 279 StrExitUnsupported:
 280   db 'vUnsupported', 0x0d, 0x0a, 0
 281
 282 StrUnkownFunction:
 283   db 'vUnknown Function', 0x0d, 0x0a, 0
 284
 285 StrEnterGetInfo:
 286   db 'vGetInfo', 0x0d, 0x0a, 0
 287
 288 StrEnterGetModeInfo:
 289   db 'vGetModeInfo', 0x0d, 0x0a, 0
 290
 291 StrEnterGetMode:
 292   db 'vGetMode', 0x0d, 0x0a, 0
 293
 294 StrEnterSetMode:
 295   db 'vSetMode', 0x0d, 0x0a, 0
 296
 297 StrEnterSetModeLegacy:
 298   db 'vSetModeLegacy', 0x0d, 0x0a, 0
 299
 300 StrUnkownMode:
 301   db 'vUnkown Mode', 0x0d, 0x0a, 0
 302
 303 StrGetPmCapabilities:
 304   db 'vGetPmCapabilities', 0x0d, 0x0a, 0
 305
 306 StrReadEdid:
 307   db 'vReadEdid', 0x0d, 0x0a, 0
 308
 309 StrLegacyMode3:
 310   db 'vLegacyMode3', 0x0d, 0x0a, 0
 311
 312
 313 StrMode1:
 314   db 'mode_640x480x32', 0x0d, 0x0a, 0
 315 StrMode2:
 316   db 'mode_800x600x32', 0x0d, 0x0a, 0
 317 StrMode3:
 318   db 'mode_1024x768x32', 0x0d, 0x0a, 0
 319 StrMode4:
 320   db 'mode_unused', 0x0d, 0x0a, 0
 321 %endif
 322
 323 CurMode:
 324   db 0x00, 0x00
 325
 326 ;
 327 ; EDID stores monitor information. For now, just send back an null item.
 328 ;
 329 Edid:
 330   db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
 331   db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
 332   db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
 333   db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
 334   db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
 335   db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
 336   db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
 337   db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
 338   db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
 339   db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
 340   db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
 341   db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
 342   db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00