Re: [Intel-gfx] [PATCH 06/21] drm/i915: Unlock PCH_PP_CONTROL always

From: Daniel Vetter
Date: Sat Oct 01 2011 - 05:35:40 EST

On Fri, Sep 30, 2011 at 04:14:40PM -0700, Keith Packard wrote:
> On Fri, 30 Sep 2011 19:09:46 +0200, Daniel Vetter <daniel@xxxxxxxx> wrote:
> > grep shows that we also write to PCH_PP_CONTROL in intel_lvds.c in the
> > dpms functions - any reasons these two writes are left out?
> Upon a bit of review:
> The bspec makes it clear that this write protect key only needs to
> be written for eDP on DPA -- it's a work-around for a bug where panel
> power sequencing wouldn't work right.
> The LVDS code does disable write protect in the _init function, which
> seems global enough, but misses the resume case. We shouldn't ever
> need to set this field though; it write protects registers only
> when the panel is running. We could presumably remove the
> write protect disable entirely in the LVDS code.
> So, I think the patch as written is correct.

Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
Daniel Vetter
Mail: daniel@xxxxxxxx
Mobile: +41 (0)79 365 57 48
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