[Intel-gfx] [PATCH] drm/i915: User POSTING_READ and I915_READ_NOTRACE in lcpll code

[Daniel Vetter]

On Wed, Aug 21, 2013 at 10:59:47AM -0300, Paulo Zanoni wrote:
> 2013/8/21 Daniel Vetter <daniel.vetter at ffwll.ch>:
> > If we don't use the return value of a mmio read our coding style is to
> > use the POSTING_READ macro. This avoids cluttering the mmio traces.
> >
> > Similarly for busy loops to wait for a bit to flip we use the _NOTRACE
> > variant to avoid filling up the tracebuffers with gunk. Spotted while
> > reading some follow-up patches from Paulo.
> >
> > While at it add the missing posting read in the lcpll enable function
> > that Paulo spotted.
> >
> > Cc: Paulo Zanoni <przanoni at gmail.com>
> > Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
> 
> Reviewed-by: Paulo Zanoni <paulo.r.zanoni at intel.com>
> 
> I'm pretty sure I added many other wait_for calls without the _NOTRACE
> in the past...

Hm, you're right and I even missed one wait_for loop without _NOTRACE in
the lcpll code. On further though we only use _NOTRACE consistently in the
mmio vfuncs for forcewake and the gt fifo stuff. Which makes sense since
those are just the details of how to write a register in the gt. But the
actual delay loops in the modeset code are probably rather interesting, so
I now think we should keep them ;-)

I'll resend with just the posting read stuff.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch