Re: [Linux-fbdev-users] rivafb + NV17

[Antonino A. D. <ad...@ho...>]

On Friday 05 November 2004 18:21, David Liontooth wrote:
> On the 2.6.9 kernel on Debian sid, rivafb loads successfully:
>
> ACPI: PCI interrupt 0000:01:00.0[A] -> GSI 11 (level, low) -> IRQ 11
> rivafb: nVidia device/chipset 10DE0176
> rivafb: nVidia Corporation NV17 [GeForce4 420 Go 32M]
> rivafb: flatpanel support enabled
> rivafb: Detected CRTC controller 1 being used
> rivafb: RIVA MTRR set to ON
> rivafb: could not retrieve EDID from DDC/I2C
> rivafb: setting virtual Y resolution to 52428
> rivafb: Detected CRTC controller 1 being used
> rivafb: Detected CRTC controller 1 being used
> Console: switching to colour frame buffer device 80x30
> rivafb: PCI nVidia NV17 framebuffer ver 0.9.5b (32MB @ 0xEC000000)
>
> Along with rivafb, these modules load:
>
> Module                  Size  Used by
> rivafb                 49924  1
> i2c_algo_bit            8968  1 rivafb
> vgastate                9472  1 rivafb
> cfbimgblt               2944  1 rivafb
> i2c_core               19088  2 rivafb,i2c_algo_bit
>
> As long as the proprietary nvidia kernel module is not loaded, this works
> fine.
>
> However, I'm only getting 640x480. My /etc/fb.modes has lots of other
> resolutions, but they're not accepted.
>
> Is this a limitation of the rivafb driver, my hardware, or something else?

Nope,  it's a bug in the rivafb driver when the EDID block cannot be accessed.

I can't submit a patch right now, but I'll give instructions on how to fix this:

1. open drivers/video/riva/fbdev.c
2. search for the function "static int __devinit rivafb_probe".
3. Somewhere near the end you should see these lines:

	fb_destroy_modedb(info->monspecs.modedb);
	info->monspecs.modedb_len = 0;
	info->monspecs.modedb = NULL;

4. Remove the line "info->monspecs.modedb_len = 0"
5. Next, search for the function "static int rivafb_check_var"
6. Look for these lines:

	if (!mode_valid && !list_empty(&info->modelist))
		return -EINVAL;

7. Change it so it becomes like this:

	if (!mode_valid && !info->monspecs.modedb_len)
		return -EINVAL;

8. Recompile and reboot. The end effect is rivafb will accept
all modelines coming from fbset as gospel truth.

Tony