help on linux-mipsel frame buffer

[Fuxin Zhang <fxzhang@ict.ac.cn>]

hello,linux-mips gurus
   Recently I am trying to make frame buffer work on my P6032 board
(from Algorithmics).I have a cirrus logic 5430,a RIVA TNT2 and a
Trident 3dImage9750 on hand.The linux kernel I am using is 2.2.14
(  mipsel 1.05? modified by Algorithmics. 
   BTW,could someone tell me how to access the mips tree and 
   what the version scheme for mipsel? I read the mips-howto.
   but although i can login to the cvs server of oss.sgi.com
   i could not find out where is the kernel. "cvs get linux"
   responded with "cannot find module 'linux'"
   I am new to mips world.
) 
and the distribution is Hardhat downloaded from oss.sgi.com
  First I try the vga16 frame buffer driver,but i can only get
some black/white strips on the screen.(after made some changes 
to the source,most important one is use pci to find and set the
vbase address). I can use tty driver,because I can switch consoles
using alt-f? on the keyboard attached to the board and even login 
and reboot the machine: just no readable display.
  Then I try to use vesa driver. This one use some vgabios code 
I commented out the x86 relevant codes and made it compiled,(again
use pci_find_device to find video memory address,and tweak the make
file to force vgacon use vesa driver). But the result is a blank 
screen.The fb driver is certainly on: I can copy to/from /dev/fb0.
but with no visual effect.
  Finally I back port the Riva TNT frame buffer code to 2.2,the result
is the same as the vesa driver.

  I suspect that the pci memory map is somewhat broken,but I checked
the source code and the bonito(P6032 north bridge) manual and found 
no obvious flaw.

  Where could i be wrong?Is there anybody has some experience with
frame buffer for mips?

  Any help will be great appreciated.

   



Regards
            Fuxin Zhang
            fxzhang@ict.ac.cn