amd64 resume, vesa and vbe

[Bruce Cran]

Hi,

I've been trying to figure out how to get my laptop working with 
suspend/resume - the backlight wasn't coming back on.  I eventually got a 
working configuration by suspending from X11 with the nvidia driver running - 
it has an rm_power_management call that seems to knows what to do.  In the 
process I found that the "int 0x10" call in amd64/acpica/acpi_wakecode.S 
causes the machine to reboot because POSTing doesn't bring the video chip back 
- from reading some Linux documentation is appears the VBE state needs 
restored too before video will work on this particular laptop.

It looks like the vesa driver does the POST and state restore in 
vesa_load_state (but it doesn't appear to get any suspend/resume events), 
while the dpms driver appears to handle suspend/resume but doesn't work with 
my laptop - it hangs on resume if hw.acpi.reset_video isn't set, but reboots 
if it is set.  Has anyone done any work getting the POST/restore sequence 
working in either of the drivers?

-- 
Bruce Cran