Yes, this is a 486+ instruction and thus not strictly legal in vm86
mode, but enough BIOSes use it (looking at you VIA) that we might as
well implement it.
After trying to switch from X to VT (or just quit) the video-amd driver
attempts to issue INT 10/0 to go to mode 3 (VGA). The emulator, running
the BIOS code, would then spit out:
c000:0282: A2 ILLEGAL EXTENDED X86 OPCODE!
The opcode was 0F A2, or CPUID; it was not implemented in the emulator.
This simple patch, against 1.3.0.0, handles the CPUID instruction in one of
two ways:
1) if ran on __i386__ or __x86_64__ then it calls the CPUID instruction
directly.
2) if ran elsewhere it returns a canned 486dx4 set of values for
function 1.
This fix allows the video-amd driver to switch back to console mode,
with the GSW BIOS.
Thanks to Symbio Technologies for funding my work, and ThinCan for
providing hardware :)
Signed-off-by: Bart Trojanowski <bart@jukie.net>
Acked-by: Eric Anholt <eric@anholt.net>
This instruction is being used in some debug VBIOSes. This implementation
doesn't even try to be accurate. Instead, it just increments the counter by a
fixed amount every time an rdtsc instruction in encountered, to avoid divides by
zero.
there but #ifdefed out. Insead of BTS, BT was executed. This patch
enables the BTS function and hooks it up the the correct opcode. (ATI
Technologies Inc.)