Re: [Intel-gfx] [PATCH 12/21] drm/i915: constify fdi link training vtable

[Jani Nikula <jani.nikula@linux.intel.com>]

On Wed, 08 Sep 2021, Dave Airlie <airlied@gmail.com> wrote:
> From: Dave Airlie <airlied@redhat.com>
>
> Avoid having writeable function pointers.

Would benefit from the call wrapper and naming.

Reviewed-by: Jani Nikula <jani.nikula@intel.com>


> ---
>  drivers/gpu/drm/i915/display/intel_display.c |  2 +-
>  drivers/gpu/drm/i915/display/intel_fdi.c     | 18 +++++++++++++++---
>  drivers/gpu/drm/i915/i915_drv.h              |  2 +-
>  3 files changed, 17 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> index 87950202f4ce..0ad577aceb9d 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -2100,7 +2100,7 @@ static void ilk_pch_enable(const struct intel_atomic_state *state,
>  	assert_pch_transcoder_disabled(dev_priv, pipe);
>  
>  	/* For PCH output, training FDI link */
> -	dev_priv->fdi_funcs.fdi_link_train(crtc, crtc_state);
> +	dev_priv->fdi_funcs->fdi_link_train(crtc, crtc_state);
>  
>  	/* We need to program the right clock selection before writing the pixel
>  	 * mutliplier into the DPLL. */
> diff --git a/drivers/gpu/drm/i915/display/intel_fdi.c b/drivers/gpu/drm/i915/display/intel_fdi.c
> index d9f952e0c67f..68aa9c7b18ec 100644
> --- a/drivers/gpu/drm/i915/display/intel_fdi.c
> +++ b/drivers/gpu/drm/i915/display/intel_fdi.c
> @@ -1005,15 +1005,27 @@ void lpt_fdi_program_mphy(struct drm_i915_private *dev_priv)
>  	intel_sbi_write(dev_priv, 0x21EC, tmp, SBI_MPHY);
>  }
>  
> +static const struct drm_i915_fdi_link_train_funcs ilk_funcs = {
> +	.fdi_link_train = ilk_fdi_link_train
> +};
> +
> +static const struct drm_i915_fdi_link_train_funcs gen6_funcs = {
> +	.fdi_link_train = gen6_fdi_link_train
> +};
> +
> +static const struct drm_i915_fdi_link_train_funcs ivb_funcs = {
> +	.fdi_link_train = ivb_manual_fdi_link_train
> +};
> +
>  void
>  intel_fdi_init_hook(struct drm_i915_private *dev_priv)
>  {
>  	if (IS_IRONLAKE(dev_priv)) {
> -		dev_priv->fdi_funcs.fdi_link_train = ilk_fdi_link_train;
> +		dev_priv->fdi_funcs = &ilk_funcs;
>  	} else if (IS_SANDYBRIDGE(dev_priv)) {
> -		dev_priv->fdi_funcs.fdi_link_train = gen6_fdi_link_train;
> +		dev_priv->fdi_funcs = &gen6_funcs;
>  	} else if (IS_IVYBRIDGE(dev_priv)) {
>  		/* FIXME: detect B0+ stepping and use auto training */
> -		dev_priv->fdi_funcs.fdi_link_train = ivb_manual_fdi_link_train;
> +		dev_priv->fdi_funcs = &ivb_funcs;
>  	}
>  }
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 461ab0a0f088..b3765222e717 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -1006,7 +1006,7 @@ struct drm_i915_private {
>  	struct drm_i915_irq_funcs irq_funcs;
>  
>  	/* fdi display functions */
> -	struct drm_i915_fdi_link_train_funcs fdi_funcs;
> +	const struct drm_i915_fdi_link_train_funcs *fdi_funcs;
>  
>  	/* display pll funcs */
>  	struct drm_i915_dpll_funcs dpll_funcs;

-- 
Jani Nikula, Intel Open Source Graphics Center