[okl4-developer] Starting with graphic output

[Remy Gottschalk]

Hi again,

On Fri, 2008-04-25 at 00:35 +1000, Geoffrey Lee wrote:
> On Thu, Apr 24, 2008 at 04:25:03PM +0000, Remy Gottschalk wrote:
> > Hi Nelson
> 
> Hi
> 
> > > 
> > > > 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.
> 
> When you mmap device objects in Linux user space on OKL4, the mapping code
> in Iguana checks whether there is an actual object backing that physical
> adddress.  For actual physical memory that's easy.  For devices
> you need to add the appropriate memory range at build time
> in the machine configuration.
> 
> As a quick fix you may be able to add a quick hack to eas_map() to 
> add backdoor range check for your framebuffer physical range.

Strangely it seems that my mmap request doesn't arrive to eas_map. I
don't really understand what this could means.




-- 
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