[okl4-developer] Starting with graphic output

[Remy Gottschalk]

Hi Nelson

On Tue, 2008-04-22 at 19:06 +1000, Nelson Tam wrote:
> Hi Remy,
> 
> On 15/04/2008, at 10:05 PM, Remy Gottschalk wrote:
> >
> > Ok, I'll stick with ia32_pc99 and ia32_pc99_vga targets for now.  
> > However
> > I still don't quite understand the differences between the two  
> > targets.
> > Could you tell me a little more one the subject ?
> 
> The difference is largely in the l4linux_config_* file that the
> Linux  
> kernel is configured with.  The first target will cause Linux to  
> output via the console driver, while the second target will cause  
> Linux to output via the generic VGA driver.
> 
> So we mentioned before that there is a minor change that is needed
> in  
> one of the configs in 1.5.  However these configs should work out of  
> the box in 2.1.
> 

I confirm that the two configs work out of the box in v2.1.

> 
> > While using ia32_pc99_vga i encountered another problem that may be
> > related to my misunderstanding. When i try to access the frame  
> > buffer. I
> > can open and mmap the device successfully but when I try to write in  
> > it
> > I get a roottask pagefault :
> >
> > roottask read pagefault at 00000018, ip=00206d7f - deny
> > --- "KD# roottask pagefault" ---
> > --------------------------------- (eip=f0106f79, esp=f0110300) ---
> 
> Hm.  Short of getting your binary and performing an object dump on the  
> faulting IP, it would be a bit hard to pinpoint where the problem may  
> be.  Let us know if there's anything we can help in that regard.
> 

Got a little hint when switching to okl4 v2.1. Now the problem is that
mmaping the framebuffer fail returning a "permission denied" error.


-- 
Remy Gottschalk - rgottschalk at linagora.com
Ingénieur informatique embarquée
Groupe LINAGORA - http://www.linagora.com
Tél.: +33(0)1 58 18 68 28 - Fax : +33(0)1 58 18 68 29