[RFC] Remove cause of 'primary plane already enabled' kernel warning

[RFC] Remove cause of 'primary plane already enabled' kernel warning

[joao.santos]

I keep seeing a warning coming from intel_enable_primary_plane() in the kernel
log. It seems someone overzelous set the primary_plane flag before calling the 
function and that causes the assert to trigger. It only seems to be polluting
log output.

I managed to boot and run a gl benchmark without getting any warnings with
this patch. Pls comment and let me know if there is more to this than 
I could see.

Thanks,
Joao.

[RFC] Remove cause of 'primary plane already enabled' kernel warning

[joao.santos]

From: Joao Santos <joao.santos@intel.com>

Remove code which is trigerring a kernel warning. The kernel sets the
primary_enable flag prior to calling intel_enable_primary_plane() which also
sets it. This causes the WARN to assert everytime.

------------[ cut here ]------------
[    5.458511] WARNING: at i915/intel_display.c:2004 intel_enable_primary_plane+0xd8/0xe0()
[    5.458511] Primary plane already enabled
[    5.458513] Modules linked in:
[    5.458516] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.10.20-263878-g086400b #10
[    5.458517] Hardware name: Intel Corporation Shark Bay Client platform/WhiteTip Mountain 1, BIOS HSWLPTU1.86C.0119.R00.1303230105 03/23/2013
[    5.458521]  ffffffff81d0dbc8 ffff8801488c3378 ffffffff8189d7a4 ffff8801488c33b8
[    5.458523]  ffffffff8105bc60 ffff8801488c33e8 ffff880147118000 0000000000000000
[    5.458525]  0000000000000000 ffff8801478bc000 ffff880147118000 ffff8801488c3418

This patch changes the code to call only intel_enable_primary_plane().

Change-Id: I0fa323e5f5ac330f88a78e7cb2f5ceefeff7d4fd
Signed-off-by: Joao Santos <joao.santos@intel.com>
---
 drivers/gpu/drm/i915/intel_display.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index ae9b5a1..8953b7c 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -3950,7 +3950,6 @@ static void ironlake_crtc_enable(struct drm_crtc *crtc)
 	 */
 	intel_crtc_load_lut(crtc);
 
-	intel_crtc->primary_enabled = true;
 	intel_update_watermarks(crtc);
 	intel_enable_pipe(dev_priv, pipe,
 			  intel_crtc->config.has_pch_encoder, false);
@@ -4097,7 +4096,6 @@ static void haswell_crtc_enable(struct drm_crtc *crtc)
 	intel_ddi_set_pipe_settings(crtc);
 	intel_ddi_enable_transcoder_func(crtc);
 
-	intel_crtc->primary_enabled = true;
 	intel_update_watermarks(crtc);
 	intel_enable_pipe(dev_priv, pipe,
 			  intel_crtc->config.has_pch_encoder, false);
@@ -4544,7 +4542,6 @@ static void valleyview_crtc_enable(struct drm_crtc *crtc)
 
 	intel_crtc_load_lut(crtc);
 
-	intel_crtc->primary_enabled = true;
 	intel_update_watermarks(crtc);
 	intel_enable_pipe(dev_priv, pipe, false, is_dsi);
 	intel_enable_primary_plane(dev_priv, plane, pipe);
@@ -4583,7 +4580,6 @@ static void i9xx_crtc_enable(struct drm_crtc *crtc)
 
 	intel_crtc_load_lut(crtc);
 
-	intel_crtc->primary_enabled = true;
 	intel_enable_pipe(dev_priv, pipe, false, false);
 	intel_enable_primary_plane(dev_priv, plane, pipe);
 	intel_enable_planes(crtc);
-- 
1.9.0

Re: [RFC] Remove cause of 'primary plane already enabled' kernel warning

[Ville Syrjälä]

On Wed, Mar 12, 2014 at 03:55:10PM +0000, joao.santos@intel.com wrote:
> From: Joao Santos <joao.santos@intel.com>
> 
> Remove code which is trigerring a kernel warning. The kernel sets the
> primary_enable flag prior to calling intel_enable_primary_plane() which also
> sets it. This causes the WARN to assert everytime.
> 
> ------------[ cut here ]------------
> [    5.458511] WARNING: at i915/intel_display.c:2004 intel_enable_primary_plane+0xd8/0xe0()
> [    5.458511] Primary plane already enabled
> [    5.458513] Modules linked in:
> [    5.458516] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.10.20-263878-g086400b #10
> [    5.458517] Hardware name: Intel Corporation Shark Bay Client platform/WhiteTip Mountain 1, BIOS HSWLPTU1.86C.0119.R00.1303230105 03/23/2013
> [    5.458521]  ffffffff81d0dbc8 ffff8801488c3378 ffffffff8189d7a4 ffff8801488c33b8
> [    5.458523]  ffffffff8105bc60 ffff8801488c33e8 ffff880147118000 0000000000000000
> [    5.458525]  0000000000000000 ffff8801478bc000 ffff880147118000 ffff8801488c3418
> 
> This patch changes the code to call only intel_enable_primary_plane().
> 
> Change-Id: I0fa323e5f5ac330f88a78e7cb2f5ceefeff7d4fd
> Signed-off-by: Joao Santos <joao.santos@intel.com>
> ---
>  drivers/gpu/drm/i915/intel_display.c | 4 ----
>  1 file changed, 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index ae9b5a1..8953b7c 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -3950,7 +3950,6 @@ static void ironlake_crtc_enable(struct drm_crtc *crtc)
>  	 */
>  	intel_crtc_load_lut(crtc);
>  
> -	intel_crtc->primary_enabled = true;
>  	intel_update_watermarks(crtc);
>  	intel_enable_pipe(dev_priv, pipe,
>  			  intel_crtc->config.has_pch_encoder, false);

There's no code like this in the driver. Are you using one of my old WIP
watermark branches or something?

-- 
Ville Syrjälä
Intel OTC