Chris Wilson <chris <at> chris-wilson.co.uk> writes:
>
> On Mon, 4 Oct 2010 22:31:20 +0200, Thomas Meyer <thomas <at> m3y3r.de> wrote:
> > [ 0.556247] [drm:init_ring_common] *ERROR* render ring head not reset to
zero ctl 00000000 head
> 02001000 tail 00000000 start 02001000
> > [ 0.556320] [drm:init_ring_common] *ERROR* render ring head forced to
zero ctl 00000000 head 00000000
> tail 00000000 start 02001000
> >
> > Bug or feature?
>
> Hardware feature, software bug. Could also be a feature of the software to
> report a hardware bug...
>
> At any rate, it shouldn't be happening and you are not alone at finding
> such errors in your logs.
> -Chris
>
Hi Chris,
Please explain what this error means & why it is happening...
On Sun, 5 Dec 2010 06:28:25 +0000 (UTC), Sriram <[email protected]> wrote:
> Please explain what this error means & why it is happening...
We wrote a zero into the register (whilst the ring is completely idle,
supposedly anyway) and read back a non-zero value. We believe the silicon
is doing evil things, we workaround it by writing the value again, and
continue on our merry way.
The dance only gets more complex as the hardware evolves.
-Chris
--
Chris Wilson, Intel Open Source Technology Centre