summaryrefslogtreecommitdiffstats
path: root/arch/x86/boot
diff options
context:
space:
mode:
authorH. Peter Anvin <hpa@zytor.com>2010-02-19 13:21:38 -0800
committerH. Peter Anvin <hpa@zytor.com>2010-02-19 13:21:38 -0800
commit8e92dc767abb58357e696a48fc3d8ce615a9c01a (patch)
tree5e36758eb4f4bdf57be5d63255b1c82bb9a945e6 /arch/x86/boot
parenteb572a5c7951288e265b3e8f9a5d37b6abb2e996 (diff)
downloadop-kernel-dev-8e92dc767abb58357e696a48fc3d8ce615a9c01a.zip
op-kernel-dev-8e92dc767abb58357e696a48fc3d8ce615a9c01a.tar.gz
x86, setup: Don't skip mode setting for the standard VGA modes
The code for setting standard VGA modes probes for the current mode, and skips the mode setting if the mode is 3 (color text 80x25) or 7 (mono text 80x25). Unfortunately, there are BIOSes, including the VMware BIOS, which report the previous mode if function 0F is queried while the screen is in a VESA mode, and of course, nothing can help a mode poked directly into the hardware. As such, the safe option is to set the mode anyway, and only query to see if we should be using mode 7 rather than mode 3. People who don't want any mode setting at all should probably use vga=0x0f04 (VIDEO_CURRENT_MODE). It's possible that should be the kernel default. Reported-by Rene Arends <R.R.Arends@hro.nl> Signed-off-by: H. Peter Anvin <hpa@zytor.com> LKML-Reference: <tip-*@git.kernel.org>
Diffstat (limited to 'arch/x86/boot')
-rw-r--r--arch/x86/boot/video-vga.c9
1 files changed, 1 insertions, 8 deletions
diff --git a/arch/x86/boot/video-vga.c b/arch/x86/boot/video-vga.c
index 819caa1..ed7aeff 100644
--- a/arch/x86/boot/video-vga.c
+++ b/arch/x86/boot/video-vga.c
@@ -42,22 +42,15 @@ static u8 vga_set_basic_mode(void)
{
struct biosregs ireg, oreg;
u16 ax;
- u8 rows;
u8 mode;
initregs(&ireg);
+ /* Query current mode */
ax = 0x0f00;
intcall(0x10, &ireg, &oreg);
mode = oreg.al;
- set_fs(0);
- rows = rdfs8(0x484); /* rows minus one */
-
- if ((oreg.ax == 0x5003 || oreg.ax == 0x5007) &&
- (rows == 0 || rows == 24))
- return mode;
-
if (mode != 3 && mode != 7)
mode = 3;
OpenPOWER on IntegriCloud