[Intel-gfx] [PATCH] drm/i915: Make primary_enabled match the actual hardware state

[Chris Wilson]

On Wed, Apr 30, 2014 at 05:43:01PM +0300, ville.syrjala at linux.intel.com wrote:
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> The BIOS can enable a pipe but leave the primary plane disabled. This
> coflicts with out current idea of primary_enabled. Read the actual
> hardware plane state and set primary_enabled appropriately.
> 
> We currently assume that primary_enabled is always true when we're about
> to disable a crtc. That needs to change now as the plane may not be
> enabled. So replace the relevant WARNs with early returns in
> intel_{enable,disable}_primary_hw_plane().
> 
> Fixes the following warning
> [    3.831602] WARNING: CPU: 0 PID: 1112 at linux/drivers/gpu/drm/i915/intel_display.c:1918 intel_disable_primary_hw_plane+0xe4/0xf0 [i915]()
> 
> which got introduced here by me:
>  commit e9e39655c0c30cddc3f8c09a757678a24dd36737
>  Author: Ville Syrjälä <ville.syrjala at linux.intel.com>
>  Date:   Mon Apr 28 15:53:25 2014 +0300
> 
>     drm/i915: Remove useless checks from primary enable/disable
> 
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
Tested-by: Chris Wilson <chris at chris-wilson.co.uk>
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre