Re: [PATCH 13/17] drm/i915/dp: Modify compressed bpp limitations for ultrajoiner

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Fri, Sep 27, 2024 at 02:08:27PM +0530, Ankit Nautiyal wrote:
> Add compressed bpp limitations for ultrajoiner.
> 
> v2: Fix the case for 1 pipe. (Ankit)
> v3: Refactor existing helper separately and add only ultrajoiner
> limitation. (Ville)
> 
> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_dp.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> index e7fe100ef8db..3d4d8e58380a 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -896,6 +896,11 @@ static u32 small_joiner_ram_max_bpp(struct intel_display *display, u32 mode_hdis
>  	return max_bpp;
>  }
>  
> +static u32 ultrajoiner_ram_max_bpp(struct intel_display *display, u32 mode_hdisplay)
> +{
> +	return (4 * 72 * 512) / mode_hdisplay;
> +}
> +
>  static
>  u32 get_max_compressed_bpp_with_joiner(struct drm_i915_private *i915,
>  				       u32 mode_clock, u32 mode_hdisplay,
> @@ -907,6 +912,9 @@ u32 get_max_compressed_bpp_with_joiner(struct drm_i915_private *i915,
>  	max_bpp = small_joiner_ram_max_bpp(display, mode_hdisplay, num_joined_pipes);
>  	max_bpp = min(max_bpp, bigjoiner_bw_max_bpp(display, mode_clock, num_joined_pipes));
>  
> +	if (num_joined_pipes == 4)
> +		max_bpp = min(max_bpp, ultrajoiner_ram_max_bpp(display, mode_hdisplay));

So here you handle the "is this ultrajoiner" check outside.
If you want to  stick to that then please use the same approach 
to deal with the bigjoiner_bw_max_bpp()+num_joined_pipes==1
issue I pointed out the other patch.

Or if you want to handle the num_joined_pipes==1 case inside 
bigjoiner_bw_max_bpp() then please adjust this to do a similar
thing.

> +
>  	return max_bpp;
>  }
>  
> -- 
> 2.45.2

-- 
Ville Syrjälä
Intel