amd64 resume, vesa and vbe

[Jung-uk Kim]

On Tuesday 16 November 2010 08:36 am, Bruce Cran wrote:
> 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?

You should not use hw.acpi.reset_video if you loaded vesa.ko.  
However, "vesa doesn't appear to get any suspend/resume events" 
concerns me.  Can you please show me "devinfo -v" output?  Also, 
please do "dd if=/dev/mem of=video.dat skip=0xc0000 bs=1 count=64k" 
and send me video.dat.

Thanks,

Jung-uk Kim