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.
(cherry picked from commit c8d066a151)
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.)
