Re: [Intel-gfx] [PATCH 3/5] drm/i915/fdi: move more FDI stuff to FDI link train hooks

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Wed, Aug 25, 2021 at 06:47:50PM +0300, Jani Nikula wrote:
> Accept slight duplication in the fdi link train hooks in exchange for
> simplification in ilk_pch_enable(). This lets us make
> ivb_update_fdi_bc_bifurcation() static again, now in intel_fdi.c.

For a moment I thought there were some order changes of the calls here,
but in the end it is crtc_enable and then link_training, so it looks
okay. Also CI passed and I trust your experiments and experience on
the order here.

So,

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>



> 
> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_display.c |  8 -------
>  drivers/gpu/drm/i915/display/intel_fdi.c     | 25 +++++++++++++++++++-
>  drivers/gpu/drm/i915/display/intel_fdi.h     |  1 -
>  3 files changed, 24 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> index f62bbff7a6be..e7b6969cd2e2 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -2059,14 +2059,6 @@ static void ilk_pch_enable(const struct intel_atomic_state *state,
>  
>  	assert_pch_transcoder_disabled(dev_priv, pipe);
>  
> -	if (IS_IVYBRIDGE(dev_priv))
> -		ivb_update_fdi_bc_bifurcation(crtc_state);
> -
> -	/* Write the TU size bits before fdi link training, so that error
> -	 * detection works. */
> -	intel_de_write(dev_priv, FDI_RX_TUSIZE1(pipe),
> -		       intel_de_read(dev_priv, PIPE_DATA_M1(pipe)) & TU_SIZE_MASK);
> -
>  	/* For PCH output, training FDI link */
>  	dev_priv->display.fdi_link_train(crtc, crtc_state);
>  
> diff --git a/drivers/gpu/drm/i915/display/intel_fdi.c b/drivers/gpu/drm/i915/display/intel_fdi.c
> index f8ffd5c032ae..f5e42985084a 100644
> --- a/drivers/gpu/drm/i915/display/intel_fdi.c
> +++ b/drivers/gpu/drm/i915/display/intel_fdi.c
> @@ -195,7 +195,7 @@ static void cpt_set_fdi_bc_bifurcation(struct drm_i915_private *dev_priv, bool e
>  	intel_de_posting_read(dev_priv, SOUTH_CHICKEN1);
>  }
>  
> -void ivb_update_fdi_bc_bifurcation(const struct intel_crtc_state *crtc_state)
> +static void ivb_update_fdi_bc_bifurcation(const struct intel_crtc_state *crtc_state)
>  {
>  	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
>  	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
> @@ -270,6 +270,13 @@ static void ilk_fdi_link_train(struct intel_crtc *crtc,
>  	i915_reg_t reg;
>  	u32 temp, tries;
>  
> +	/*
> +	 * Write the TU size bits before fdi link training, so that error
> +	 * detection works.
> +	 */
> +	intel_de_write(dev_priv, FDI_RX_TUSIZE1(pipe),
> +		       intel_de_read(dev_priv, PIPE_DATA_M1(pipe)) & TU_SIZE_MASK);
> +
>  	/* FDI needs bits from pipe first */
>  	assert_pipe_enabled(dev_priv, crtc_state->cpu_transcoder);
>  
> @@ -373,6 +380,13 @@ static void gen6_fdi_link_train(struct intel_crtc *crtc,
>  	i915_reg_t reg;
>  	u32 temp, i, retry;
>  
> +	/*
> +	 * Write the TU size bits before fdi link training, so that error
> +	 * detection works.
> +	 */
> +	intel_de_write(dev_priv, FDI_RX_TUSIZE1(pipe),
> +		       intel_de_read(dev_priv, PIPE_DATA_M1(pipe)) & TU_SIZE_MASK);
> +
>  	/* Train 1: umask FDI RX Interrupt symbol_lock and bit_lock bit
>  	   for train result */
>  	reg = FDI_RX_IMR(pipe);
> @@ -510,6 +524,15 @@ static void ivb_manual_fdi_link_train(struct intel_crtc *crtc,
>  	i915_reg_t reg;
>  	u32 temp, i, j;
>  
> +	ivb_update_fdi_bc_bifurcation(crtc_state);
> +
> +	/*
> +	 * Write the TU size bits before fdi link training, so that error
> +	 * detection works.
> +	 */
> +	intel_de_write(dev_priv, FDI_RX_TUSIZE1(pipe),
> +		       intel_de_read(dev_priv, PIPE_DATA_M1(pipe)) & TU_SIZE_MASK);
> +
>  	/* Train 1: umask FDI RX Interrupt symbol_lock and bit_lock bit
>  	   for train result */
>  	reg = FDI_RX_IMR(pipe);
> diff --git a/drivers/gpu/drm/i915/display/intel_fdi.h b/drivers/gpu/drm/i915/display/intel_fdi.h
> index 135802e4da68..cda9a32c25ba 100644
> --- a/drivers/gpu/drm/i915/display/intel_fdi.h
> +++ b/drivers/gpu/drm/i915/display/intel_fdi.h
> @@ -16,7 +16,6 @@ int intel_fdi_link_freq(struct drm_i915_private *i915,
>  			const struct intel_crtc_state *pipe_config);
>  int ilk_fdi_compute_config(struct intel_crtc *intel_crtc,
>  			   struct intel_crtc_state *pipe_config);
> -void ivb_update_fdi_bc_bifurcation(const struct intel_crtc_state *crtc_state);
>  void intel_fdi_normal_train(struct intel_crtc *crtc);
>  void ilk_fdi_disable(struct intel_crtc *crtc);
>  void ilk_fdi_pll_disable(struct intel_crtc *intel_crtc);
> -- 
> 2.20.1
>