Re: [PATCH 1/3] cyber2000fb: fix machine hang on module load

[Jeff Garzik]

On 07/31/2010 05:25 PM, Russell King - ARM Linux wrote:
> On Sat, Jul 31, 2010 at 05:21:33PM -0400, Jeff Garzik wrote:
> > On 07/31/2010 04:55 PM, Ondrej Zary wrote:
> > > I was testing two CyberPro 2000 based PCI cards on x86 and the machine always
> > > hanged completely when the cyber2000fb module was loaded. It seems that the
> > > card hangs when some registers are accessed too quickly after writing RAMDAC
> > > control register. With this patch, both card work.
> > >
> > > Add delay after RAMDAC control register write to prevent hangs on module load.
> > >
> > > Signed-off-by: Ondrej Zary<linux@xxxxxxxxxxxxxxxxxxxx>
> > >
> > > --- linux-2.6.35-rc2-orig/drivers/video/cyber2000fb.c	2010-06-06 05:43:24.000000000 +0200
> > > +++ linux-2.6.35-rc3/drivers/video/cyber2000fb.c	2010-07-27 23:12:37.000000000 +0200
> > > @@ -436,6 +436,8 @@ static void cyber2000fb_write_ramdac_ctr
> > >    	cyber2000fb_writeb(i | 4, 0x3cf, cfb);
> > >    	cyber2000fb_writeb(val, 0x3c6, cfb);
> > >    	cyber2000fb_writeb(i, 0x3cf, cfb);
> > > +	/* prevent card lock-up observed on x86 with CyberPro 2000 */
> > > +	cyber2000fb_readb(0x3cf, cfb);
> > >    }
> >
> > IIRC, cyber2000 is basically an S3 graphics chip.
>
> No such luck.  It's a proprietary Integraphics chip, mainly used in
> ARM Netwinders some 10 years ago.  It's completely different from the
> S3 chips such as Trio64.

Ah, I stand corrected.  Maybe that was cyberfb I was remembering...

	Jeff



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/