[Intel-gfx] [PATCH] drm/i915: Add debugfs hooks for messign with watermark latencies

[Damien Lespiau]

On Wed, Jan 22, 2014 at 04:38:11PM +0200, Ville Syrjälä wrote:
> On Wed, Jan 22, 2014 at 02:26:26PM +0000, Damien Lespiau wrote:
> > On Wed, Jan 22, 2014 at 02:36:08PM +0200, ville.syrjala at linux.intel.com wrote:
> > > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > > 
> > > Add a few new debugfs files which allow changing the watermark memory
> > > latency values during runtime. This can be used to determine the if the
> > > original BIOS provided latency values are no good.
> > > 
> > > v2: Drop superfluous plane name from output
> > >     Take modeset locks around the latency value read/write
> > 
> > Huum, I was thinking that it may be practical to write the latencies in
> > usec instead of the level dependent (and potentially platform dependent)
> > units. It can also be done in the small helper from user space anyway.
> 
> Yeah I'm not really convinced I've designed this interface properly. I
> also slightly dislike the fact that the input and output formats aren't
> the same. So I was wondering if I should just change the output format
> to match the non decorated input format, and then leave it up to the
> userspace to make it look nicer. But it's debugfs so I'm not too worried
> about the longevity of the design.

On second thoughts, I think I'd really like writing the latencies as
"x.y" (usec) in that file. Can be done later though.

-- 
Damien