From 8e92dc767abb58357e696a48fc3d8ce615a9c01a Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Fri, 19 Feb 2010 13:21:38 -0800 Subject: [PATCH] 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 Signed-off-by: H. Peter Anvin LKML-Reference: --- arch/x86/boot/video-vga.c | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) diff --git a/arch/x86/boot/video-vga.c b/arch/x86/boot/video-vga.c index 819caa1f2008..ed7aeff786b2 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; -- 2.39.5