Re: Problem with i820 AGP patch

[Nicolas Aspert]

Daniele Venzano wrote:

> Your patch to add AGP support for i820 chipset doesn't work for me, if I
> load agpgart module with agp_try_unsupported=1 I get:
> 
> -
> Linux agpgart interface v0.99 (c) Jeff Hartmann
> agpgart: Maximum main memory to use for agp memory: 262M
> agpgart: Trying generic Intel routines for device id: 2501
> 						^^^^^^^^^^^^^
> agpgart: AGP aperture is 256M @ 0xd0000000
> -

Here is what I have in 'drivers/pci/pci.ids' :

         2500  82820 820 (Camino) Chipset Host Bridge (MCH)
                 1043 801c  P3C-2000 system chipset
         2501  82820 820 (Camino) Chipset Host Bridge (MCH)
                 1043 801c  P3C-2000 system chipset
         250b  82820 820 (Camino) Chipset Host Bridge
         250f  82820 820 (Camino) Chipset PCI to AGP Bridge

So I guess that 0x2500 and 0x2501 should be initialized in the same way, 
through the same routines. Unfortunately, I dont have such a machine to 
test... Can you send what 'lspci -ev' shows ?

> That device id is different from the corresponding line in apg.h:174
> #define PCI_DEVICE_ID_INTEL_820_0       0x2500
> 
> I tried to change that line in:
> #define PCI_DEVICE_ID_INTEL_820_0       0x2501
> 
> And it worked! But I don't know why the id for your chip is different
> from mine... 
> 

It worked, but in which way ? Did you test X+OpenGL apps to see whether 
it did the trick ? The fact that the module loads itself is not always 
sufficient to say that it works (believe me :-)

> My motherboard is an Asus P3C2000 with a P3 500 running kernel 2.4.14
> 
> 
> I've also another problem (I think AGP related) with DRI/DRM ang XFree
> 4.1.0, but I'm still working on it.
> If I try running some OpenGL app with more than 256Mb of RAM, the system hangs
> (need hard reset, no SysReq works). This happens with 2.4.13 and 2.4.14,
> before I hadn't tried since I had only 128Mb...)
> Someone can please tell me if this problem has something to do with
> having a "Maximum main memory to use for agp memory" value grater than
> AGP aperture value ?
> 

With your custom patch, or with the 'generic' stuff ?

Regards.
-- 
Nicolas Aspert      Signal Processing Laboratory (LTS)
Swiss Federal Institute of Technology (EPFL)