yaboot: text mode or graphics mode?

yaboot: text mode or graphics mode?

[sumedh tirodkar]

Does anyone knw what happens when we boot into yaboot,whether we are
in text mode or graphics mode? If text mode then wat is the address of
the screen? I need it to print some debug info..bt i either dnt seem
to get the buffer address correct or i m not in text mode as yaboot
has already switched to some other mode...

Regards,
Sumedh

Re: yaboot: text mode or graphics mode?

[sumedh tirodkar]

I just found out that openfirmware boots into graphics mode(non-text
mode). Now i wish to switch back to text mode. how do i do this?

On Sat, Dec 20, 2008 at 9:37 PM, sumedh tirodkar
<sumedhtirodkar@gmail.com> wrote:
> Does anyone knw what happens when we boot into yaboot,whether we are
> in text mode or graphics mode? If text mode then wat is the address of
> the screen? I need it to print some debug info..bt i either dnt seem
> to get the buffer address correct or i m not in text mode as yaboot
> has already switched to some other mode...
>
> Regards,
> Sumedh
>

Re: yaboot: text mode or graphics mode?

[Matt Sealey]

sumedh tirodkar wrote:
> I just found out that openfirmware boots into graphics mode(non-text
> mode). Now i wish to switch back to text mode. how do i do this?

Unfortunately unless you are running some kind of yaboot-accessible or 
firmware-accessible x86 BIOS emulation, this isn't possible.

--
Matt

Re: yaboot: text mode or graphics mode?

[sumedh tirodkar]

Isn't there any other way that i can access the VGA registers? So as
to reconfigure them...

-Sumedh

On Wed, Dec 31, 2008 at 4:15 AM, Matt Sealey <matt@genesi-usa.com> wrote:
> sumedh tirodkar wrote:
>>
>> I just found out that openfirmware boots into graphics mode(non-text
>> mode). Now i wish to switch back to text mode. how do i do this?
>
> Unfortunately unless you are running some kind of yaboot-accessible or
> firmware-accessible x86 BIOS emulation, this isn't possible.
>
> --
> Matt
>

Re: yaboot: text mode or graphics mode?

[Matt Sealey]

They should be mapped into PCI address space with the rest, you should 
note though that a bunch of people have asked this a bunch of times and 
the response is usually null.

If you want to output debugging info, try a serial port, or if you're 
still at the point in boot where the OF is still around, you can still 
output to it (check prom_init.c) and if not, the open firmware 
framebuffer console driver is your best friend..

sumedh tirodkar wrote:
> Isn't there any other way that i can access the VGA registers? So as
> to reconfigure them...
> 
> -Sumedh
> 
> On Wed, Dec 31, 2008 at 4:15 AM, Matt Sealey <matt@genesi-usa.com> wrote:
>> sumedh tirodkar wrote:
>>> I just found out that openfirmware boots into graphics mode(non-text
>>> mode). Now i wish to switch back to text mode. how do i do this?
>> Unfortunately unless you are running some kind of yaboot-accessible or
>> firmware-accessible x86 BIOS emulation, this isn't possible.
>>
>> --
>> Matt
>>