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

[David L. <lio...@co...>]

Hi Tony,

Thank you for the hints and suggestions.

>>I'm also wondering if it's possible to tell the rivafb module to use
>>the right mode when loading -- at the moment it loads into 640x480
>>and then I use fbset to change it to 1280x854. Here's the first
>>entry in my /etc/fb.modes:
>>    
>>
>Currently, no.  You have to add your modeline into the kernel's
>modeline table which is located in drivers/video/modedb.c (unless
>your mode is already present).
>  
>
I added these lines:

 {
        /* 1280x854 @ 85 Hz, 47.58 kHz hsync */
        NULL, 85, 1280, 854, 11723, 240, 16, 31, 0, 256, 7,
        FB_SYNC_HOR_HIGH_ACT|FB_SYNC_VERT_HIGH_ACT, FB_VMODE_NONINTERLACED
    },

and these (shifting the numbers down):

/* 18 1280x854-85 VESA */
        { NULL, 85, 1280, 854, 11723, 240, 16, 31, 0, 256, 7,
          FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
          FB_VMODE_NONINTERLACED, FB_MODE_IS_VESA },

But got no effect. It's not critical.

>>The module doesn't seem to accept mode parameters, however.
>>    
>>
>It does, except for the startup mode, so if rivafb is compiled as a module
>(and this is true for most drivers), it will only use the default mode.
>  
>
I don't think I understand -- do you mean that a parameter can be
passed if the driver is compiled into the kernel?

>...I was answering the part of your question about being able to
>remove rivafb, and the answer is yes you can, as long as the framebuffer 
>console is disabled.
>  
>
Got it -- I rebuilt the kernel with the framebuffer console as a
module, and can confirm that directfb still works under rivafb,
which now can be removed. I run a dual monitor setup, so
when I remove rivafb, the built-in laptop screen flickers and
only the second, attached LCD reverts to a usable console
(with slightly mangled fonts).

The main downside is that the graphics quality is now clearly
inferior -- the picture is fuzzy -- and there's no sound in my case.
With the framebuffer console loaded, the graphics are excellent
and the sound perfect -- if anything, it's nicer to watch movies
this way than in X.

To sum up, what works for me is this:

  * modify drivers/video/riva/fbdev.c as you suggest
  * add the correct mode to /etc/fb.modes
     (modeline2fb -d 8 /etc/X11/XF86Config-4)
  * rmmod nvidia && modprobe fbcon and rivafb
  * fbset the new mode
  * mplayer -vo directfb *.vob
  * fbi *.jpg -t 5 -autozoom -edit for slideshows

The framebuffer console and rivafb are really attractive -- great
crisp graphics and fonts, low cpu usage, minimal overhead.

There are still kinks that need to be ironed out --

  * moving the mouse in mplayer freezes the system
  * EDID isn't working on N17, works fine in XFree86
     -- so wrong initial screen size/resolution
     -- which cannot easily be corrected in modedb.c
     -- mouse stays in a 640x480 area even after resizing
  * cannot unload fbcon+rivafb
  * resolution poor in rivafb without fbcon (and so what?)

I think this is really cool work -- and thanks for giving me
such detailed feedback. I've been wanting to have this
working for years.

Cheers,
Dave