[Intel-gfx] [PATCH] drm/i915/mtl: Introduce FBC B

[Kahola, Mika]

> -----Original Message-----
> From: Nikula, Jani <jani.nikula at intel.com>
> Sent: Wednesday, August 17, 2022 3:26 PM
> To: intel-gfx at lists.freedesktop.org
> Cc: Nikula, Jani <jani.nikula at intel.com>; Ville Syrjälä
> <ville.syrjala at linux.intel.com>; Kahola, Mika <mika.kahola at intel.com>
> Subject: [PATCH] drm/i915/mtl: Introduce FBC B
> 
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> MTL introduces a second FBC engine. The two FBC engines can operate entirely
> independently, FBC A serving pipe A and FBC B serving pipe B.
> 
> The one place where things might go a bit wrong is the CFB allocation from
> stolen. We might have to consider some change to the allocation strategy to
> have a better chance of both engines being able to allocate its CFB. Maybe FBC
> A should allocate bottom up and FBC B top down, or something? For the
> moment the allocation strategy is DRM_MM_INSERT_BEST for both.
> 
> Cc: Mika Kahola <mika.kahola at intel.com>
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Signed-off-by: Jani Nikula <jani.nikula at intel.com>

Reviewed-by: Mika Kahola <mika.kahola at intel.com>

> ---
>  drivers/gpu/drm/i915/display/intel_fbc.h | 1 +
>  drivers/gpu/drm/i915/i915_pci.c          | 3 ++-
>  2 files changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_fbc.h
> b/drivers/gpu/drm/i915/display/intel_fbc.h
> index db60143295ec..4adb98afe6ff 100644
> --- a/drivers/gpu/drm/i915/display/intel_fbc.h
> +++ b/drivers/gpu/drm/i915/display/intel_fbc.h
> @@ -19,6 +19,7 @@ struct intel_plane_state;
> 
>  enum intel_fbc_id {
>  	INTEL_FBC_A,
> +	INTEL_FBC_B,
> 
>  	I915_MAX_FBCS,
>  };
> diff --git a/drivers/gpu/drm/i915/i915_pci.c b/drivers/gpu/drm/i915/i915_pci.c
> index 9fd788e147a3..d8446bb25d5e 100644
> --- a/drivers/gpu/drm/i915/i915_pci.c
> +++ b/drivers/gpu/drm/i915/i915_pci.c
> @@ -1111,7 +1111,8 @@ static const struct intel_device_info pvc_info = {
>  #define XE_LPDP_FEATURES	\
>  	XE_LPD_FEATURES,	\
>  	.display.ver = 14,	\
> -	.display.has_cdclk_crawl = 1
> +	.display.has_cdclk_crawl = 1, \
> +	.display.fbc_mask = BIT(INTEL_FBC_A) | BIT(INTEL_FBC_B)
> 
>  __maybe_unused
>  static const struct intel_device_info mtl_info = {
> --
> 2.34.1