From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <e1f3a2fa63011241b780082adf3b10d7@plan9.bell-labs.com>
Date: Fri, 10 Mar 2006 16:31:31 -0500
From: jmk@plan9.bell-labs.com
To: 9fans@cse.psu.edu
Subject: Re: [9fans] kernels
In-Reply-To: <20060310211652.17E17B4972@dexter-peak.quanstro.net>
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To be fair, it's not the 'standard's that are at fault here.
Using VESA requires taking the processor out of protected mode
and jumping into the BIOS and that's difficult with 2 processors
as we need to make sure they are all agreed on what's going on
and interrupts are properly disabled, etc. The Plan 9 x86 SMP
code wasn't written with those goals in mind. It should be possible
but clearly we didn't get it right and it's a low-priority item.

You will need to get the changes I made today for
/sys/src/cmd/aux/vga/clgd542x.c and /sys/src/9/pc/vgaclgd542x.c,
make a new kernel and aux/vga. Run aux/vga -B | sed 20q and check
the new entry in /lib/vgadb matches the starting position of
the string in the BIOS output. If it's all OK then change the
plan9.ini monitor= to something real (not VESA) and reboot.

--jim

On Fri Mar 10 16:17:55 EST 2006, quanstro@quanstro.net wrote:
> hey, thanks! i didn't know that there was a problem with vesa and smp.
> (how do they come up with these standards.)
>
> do i need to change my configuration to take advantage of this?
>
> here's what i currently have: (i know the bootdisk line is wrong;
> i killed my 9fat partition somehow. i didn't trust the install with
> my fossil so i cooked this up (incorrectly) by hand.)
>
> ; cat plan9.ini
> *nomp=1
> bootfile=sdC0!9fat!9pcf
> bootdisk=local!#S/sdC0/fossil
> mouseport=ps2
> monitor=vesa
> vgasize=1280x1024x8
>
> jmk@plan9.bell-labs.com writes
> |
> | Ah. There's a pile of those in my office (recycled VA Linux servers),
> | let's hook one up...
> |
> | The problem is you cannot run VESA with SMP, one of the processors
> | ends up looping somewhere it shouldn't (it has probably crashed) and
> | the CL-GD5480 chip is not recognised by aux/vga. So...
> |
> | new /lib/vgadb, /sys/src/cmd/aux/vga/clgd542x.c and /sys/src/9/pc/vgaclgd542x.c
> | on sources.
> |
> | --jim
> |