Check if active video mode is changed after OpROM starts, if active video mode is not changed, skip INT10 calls to improve performance.

Signed-off-by: Li Elvin <elvin.li@intel.com>
Reviewed-by: Yao Jiewen<jiewen.yao@intel.com>


git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13609 6f19259b-4bc3-4df7-8a09-765794883524
This commit is contained in:
li-elvin 2012-08-13 09:33:49 +00:00
parent e27ad65778
commit edf4af6fb9
2 changed files with 10 additions and 4 deletions

View File

@ -132,6 +132,7 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
#define LEGACY_PCI_TRACE_00E LEGACY_PCI_TRACE + 0x0E
#define LEGACY_PCI_TRACE_00F LEGACY_PCI_TRACE + 0x0F
#define BDA_VIDEO_MODE 0x49
typedef struct {
UINTN PciSegment;

View File

@ -2380,7 +2380,7 @@ LegacyBiosInstallRom (
//
// Store current mode settings since PrepareToScanRom may change mode.
//
VideoMode = *(UINT8 *) ((UINTN) 0x449);
VideoMode = *(UINT8 *) ((UINTN) (0x400 + BDA_VIDEO_MODE));
}
//
// Notify the platform that we are about to scan the ROM
@ -2520,10 +2520,15 @@ LegacyBiosInstallRom (
//
// Set mode settings since PrepareToScanRom may change mode
//
if (VideoMode != *(UINT8 *) ((UINTN) (0x400 + BDA_VIDEO_MODE))) {
//
// The active video mode is changed, restore it to original mode.
//
Regs.H.AH = 0x00;
Regs.H.AL = VideoMode;
Private->LegacyBios.Int86 (&Private->LegacyBios, 0x10, &Regs);
}
}
//
// Regs.X.AX from the adapter initializion is ignored since some adapters
// do not follow the standard of setting AX = 0 on success.