Re: Screen garbled - Was :Re: Kernel panic : VFS : unable to mount root fs

["Chris Tillman" <tillman@voicetrak.com>]

On Tue, Oct 29, 2002 at 12:57:51PM -0800, Johan en Katrien Dewaele wrote:
> Hi again,
> 
> --- Chris Tillman <tillman@voicetrak.com> wrote:
> > On Sat, Oct 26, 2002 at 04:56:56AM -0700, Johan en
> > Katrien Dewaele wrote:
> > > Hi people,
> > > I need your help/advice on this one : I'm a newbie
> > in
> > > this PPC-Linux thing.
> > > 
> > > I acquired this old Mac PPC 4400/200 
> 
> Changed strategy : put my Linux-disk on ide0 - and
> redid install so I could go with quik.
> 
> Now I have another problem : 
> When boot-floppy boots I get a nice screenoutput with
> the penguin on top : kernel detects following (dmesg
> output) :
> 
> MacOs display is /bandit/ATY,264VT
> Using unsupported 640x480 ATY,264VT at 81800480,
> depth=8, pitch=640
> Console: switching to colour frame buffer device 80x30
> fb0: Open Firmware frame buffer device on
> /bandit/ATY,264VT
> etc...
> 
> When I reboot (during the install, after making
> harddisk bootable) I get no(or garbled) screen-output.
> 
> I've tried different combinations of c -and vmode with
> video=atyfb. With following combinations i get output
> but it is scrolling fast/garbled and not usable. :
> vmode:6,cmode:8 
>       5       8
>      14       1 
> 
> I can see through the "waves" that the installer tries
> to continue the install.
> Replaced atyfb with offb and ofonly : no go.
> 
> So : I guess I got some wrong parameters in the PRAM
> and/or quik.conf.  What combination/frame buffer does
> the boot-floppy use ? Can anybody shed a light ?
> 
> This is what I've put in PRAM with nvsetenv:
> 
> little-endian	false
> real-mode	false
> auto-boot	true
> diag-switch	false
> fcode-debug	false
> oem-banner	false
> oem-logo	false
> use-nvramrc	false
> real-base 	0xffffffff
> real-size 	0x100000
> virt-base 	0xffffffff
> virt-size 	0x100000
> load-base 	0x600000
> pci-probe-list 	0xffffffff
> screen-#columns	0x64
> screen-#rows	0x28
> selftest-#megs 	0x0
> boot-device 	ata/ata-disk@0:0
> boot-file   	 ata/ata-disk@0:2/vmlinux

On mine, I just put Linux here, not the path to the kernel.
Then the quik.conf Linux label controls the boot.

> video=atyfb:vmode:5,cmode:8
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
I don't know what this is doing in here? 

> diag-device 	fd-diags
> diag-file
> input-device 	kbd
> output-device 	/bandit/ATY,264VT
> oem-banner
> oem-logo
> nvramrc
> boot-command 	begin ['] boot catch 1000 ms cr again
> 
> quik.conf:
> 
> default=Linux
> timeout=100
> root=/dev/hda2
> partition=2
> image=/vmlinux   
        ^^^^^^^^
quik doesn't grok symlinks, you must have copied your kernel there?
> 	append="video=atyfb:vmode:5,cmode:8"
> 	label=Linux
> 	read-only

Things to try:
* append="video=atyfb:vmode:5"
* append="video=ofonly"
* don't append anything

(append="video=ofonly" is what the standard boot floppy uses).

Remember you always have to run quik after changing the quik.conf

According to http://docs.info.apple.com/article.html?artnum=112401
your machine supports several modes, you might want to try some 
of the other vmode numbers as well.



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|            Chris Tillman        tillman@voicetrak.com          |
|                  To Have, Give All to All (ACIM)               |
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