[Intel-gfx] [PATCH] drm/i915: Cache max number of pipes

[Saarinen, Jani]

HI, 
> -----Original Message-----
> From: Intel-gfx [mailto:intel-gfx-bounces at lists.freedesktop.org] On Behalf
> Of Mika Kahola
> Sent: torstai 12. lokakuuta 2017 9.30
> To: intel-gfx at lists.freedesktop.org
> Cc: ville.syrjala at intel.linux.com; Vivi, Rodrigo <rodrigo.vivi at intel.com>
> Subject: [Intel-gfx] [PATCH] drm/i915: Cache max number of pipes
> 
> CI system spotted an error on CFL system when running IGT tests with display
> disabled. In this case, the 'INTEL_INFO(dev_priv)->num_pipes'
> is set to 0. This will cause that we prematurely return from 'get_saved_enc()'.
> 
> To fix this issue, the patch introduces a 'max_pipes' variable which caches
> the maximum number of available pipes.
> 
> Reference: https://bugs.freedesktop.org/show_bug.cgi?id=103206
> Signed-off-by: Mika Kahola <mika.kahola at intel.com>
This was also tested successfully on try-bot fixing issue seen, so maybe we can say tested-by: try-bot? 

> ---
>  drivers/gpu/drm/i915/i915_drv.h          | 1 +
>  drivers/gpu/drm/i915/intel_audio.c       | 2 +-
>  drivers/gpu/drm/i915/intel_device_info.c | 2 ++
>  3 files changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.h
> b/drivers/gpu/drm/i915/i915_drv.h index 770305b..6229ff8 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -868,6 +868,7 @@ struct intel_device_info {
>  	u8 num_pipes;
>  	u8 num_sprites[I915_MAX_PIPES];
>  	u8 num_scalers[I915_MAX_PIPES];
> +	u8 max_pipes;
> 
>  	unsigned int page_sizes; /* page sizes supported by the HW */
> 
> diff --git a/drivers/gpu/drm/i915/intel_audio.c
> b/drivers/gpu/drm/i915/intel_audio.c
> index 0ddba16..147bd3d 100644
> --- a/drivers/gpu/drm/i915/intel_audio.c
> +++ b/drivers/gpu/drm/i915/intel_audio.c
> @@ -754,7 +754,7 @@ static struct intel_encoder *get_saved_enc(struct
> drm_i915_private *dev_priv,  {
>  	struct intel_encoder *encoder;
> 
> -	if (WARN_ON(pipe >= INTEL_INFO(dev_priv)->num_pipes))
> +	if (WARN_ON(pipe >= INTEL_INFO(dev_priv)->max_pipes))
>  		return NULL;
> 
>  	/* MST */
> diff --git a/drivers/gpu/drm/i915/intel_device_info.c
> b/drivers/gpu/drm/i915/intel_device_info.c
> index 875d428..ba1a807 100644
> --- a/drivers/gpu/drm/i915/intel_device_info.c
> +++ b/drivers/gpu/drm/i915/intel_device_info.c
> @@ -376,6 +376,8 @@ void intel_device_info_runtime_init(struct
> drm_i915_private *dev_priv)
>  			info->num_sprites[pipe] = 1;
>  	}
> 
> +	info->max_pipes = info->num_pipes;
> +
>  	if (i915_modparams.disable_display) {
>  		DRM_INFO("Display disabled (module parameter)\n");
>  		info->num_pipes = 0;
> --
> 2.7.4


Jani Saarinen
Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo