[Intel-gfx] [PATCH 10/10] drm/i915: Perform a central cdclk state sanity check

[Rodrigo Vivi]

On Tue, Oct 24, 2017 at 09:52:16AM +0000, Ville Syrjala wrote:
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> WARN if the cdclk state doesn't match what we expect after programming.
> And let's remove the WARN from bdw_set_cdclk() that's trying to achieve
> the same thing in a more limite fashion.
> 
> Also take the opportunity to refactor the code to use a common function
> for dumping out a cdclk state.
> 
> Cc: Mika Kahola <mika.kahola at intel.com>
> Cc: Manasi Navare <manasi.d.navare at intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>

better code, better logs and right checks.

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

> ---
>  drivers/gpu/drm/i915/intel_cdclk.c   | 30 +++++++++++++++++++-----------
>  drivers/gpu/drm/i915/intel_display.c |  3 +++
>  drivers/gpu/drm/i915/intel_drv.h     |  2 ++
>  3 files changed, 24 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_cdclk.c b/drivers/gpu/drm/i915/intel_cdclk.c
> index fedfe3c720b6..51cd23dd8676 100644
> --- a/drivers/gpu/drm/i915/intel_cdclk.c
> +++ b/drivers/gpu/drm/i915/intel_cdclk.c
> @@ -768,10 +768,6 @@ static void bdw_set_cdclk(struct drm_i915_private *dev_priv,
>  	I915_WRITE(CDCLK_FREQ, DIV_ROUND_CLOSEST(cdclk, 1000) - 1);
>  
>  	intel_update_cdclk(dev_priv);
> -
> -	WARN(cdclk != dev_priv->cdclk.hw.cdclk,
> -	     "cdclk requested %d kHz but got %d kHz\n",
> -	     cdclk, dev_priv->cdclk.hw.cdclk);
>  }
>  
>  static int skl_calc_cdclk(int min_cdclk, int vco)
> @@ -1068,6 +1064,8 @@ static void skl_sanitize_cdclk(struct drm_i915_private *dev_priv)
>  		goto sanitize;
>  
>  	intel_update_cdclk(dev_priv);
> +	intel_dump_cdclk_state(&dev_priv->cdclk.hw, "Current CDCLK");
> +
>  	/* Is PLL enabled and locked ? */
>  	if (dev_priv->cdclk.hw.vco == 0 ||
>  	    dev_priv->cdclk.hw.cdclk == dev_priv->cdclk.hw.ref)
> @@ -1407,6 +1405,7 @@ static void bxt_sanitize_cdclk(struct drm_i915_private *dev_priv)
>  	u32 cdctl, expected;
>  
>  	intel_update_cdclk(dev_priv);
> +	intel_dump_cdclk_state(&dev_priv->cdclk.hw, "Current CDCLK");
>  
>  	if (dev_priv->cdclk.hw.vco == 0 ||
>  	    dev_priv->cdclk.hw.cdclk == dev_priv->cdclk.hw.ref)
> @@ -1713,6 +1712,7 @@ static void cnl_sanitize_cdclk(struct drm_i915_private *dev_priv)
>  	u32 cdctl, expected;
>  
>  	intel_update_cdclk(dev_priv);
> +	intel_dump_cdclk_state(&dev_priv->cdclk.hw, "Current CDCLK");
>  
>  	if (dev_priv->cdclk.hw.vco == 0 ||
>  	    dev_priv->cdclk.hw.cdclk == dev_priv->cdclk.hw.ref)
> @@ -1826,6 +1826,14 @@ bool intel_cdclk_changed(const struct intel_cdclk_state *a,
>  		a->voltage_level != b->voltage_level;
>  }
>  
> +void intel_dump_cdclk_state(const struct intel_cdclk_state *cdclk_state,
> +			    const char *context)
> +{
> +	DRM_DEBUG_DRIVER("%s %d kHz, VCO %d kHz, ref %d kHz, voltage level %d\n",
> +			 context, cdclk_state->cdclk, cdclk_state->vco,
> +			 cdclk_state->ref, cdclk_state->voltage_level);
> +}
> +
>  /**
>   * intel_set_cdclk - Push the CDCLK state to the hardware
>   * @dev_priv: i915 device
> @@ -1843,11 +1851,15 @@ void intel_set_cdclk(struct drm_i915_private *dev_priv,
>  	if (WARN_ON_ONCE(!dev_priv->display.set_cdclk))
>  		return;
>  
> -	DRM_DEBUG_DRIVER("Changing CDCLK to %d kHz, VCO %d kHz, ref %d kHz, voltage_level %d\n",
> -			 cdclk_state->cdclk, cdclk_state->vco,
> -			 cdclk_state->ref, cdclk_state->voltage_level);
> +	intel_dump_cdclk_state(cdclk_state, "Changing CDCLK to");
>  
>  	dev_priv->display.set_cdclk(dev_priv, cdclk_state);
> +
> +	if (WARN(intel_cdclk_changed(&dev_priv->cdclk.hw, cdclk_state),
> +		 "cdclk state doesn't match!\n")) {
> +		intel_dump_cdclk_state(&dev_priv->cdclk.hw, "[hw state]");
> +		intel_dump_cdclk_state(cdclk_state, "[sw state]");
> +	}
>  }
>  
>  static int intel_pixel_rate_to_cdclk(struct drm_i915_private *dev_priv,
> @@ -2280,10 +2292,6 @@ void intel_update_cdclk(struct drm_i915_private *dev_priv)
>  {
>  	dev_priv->display.get_cdclk(dev_priv, &dev_priv->cdclk.hw);
>  
> -	DRM_DEBUG_DRIVER("Current CD clock rate: %d kHz, VCO: %d kHz, ref: %d kHz\n",
> -			 dev_priv->cdclk.hw.cdclk, dev_priv->cdclk.hw.vco,
> -			 dev_priv->cdclk.hw.ref);
> -
>  	/*
>  	 * 9:0 CMBUS [sic] CDCLK frequency (cdfreq):
>  	 * Programmng [sic] note: bit[9:2] should be programmed to the number
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index b5fa643e1812..7d7952b78a3b 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -8857,7 +8857,9 @@ static void hsw_restore_lcpll(struct drm_i915_private *dev_priv)
>  	}
>  
>  	intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL);
> +
>  	intel_update_cdclk(dev_priv);
> +	intel_dump_cdclk_state(&dev_priv->cdclk.hw, "Current CDCLK");
>  }
>  
>  /*
> @@ -14358,6 +14360,7 @@ void intel_modeset_init_hw(struct drm_device *dev)
>  	struct drm_i915_private *dev_priv = to_i915(dev);
>  
>  	intel_update_cdclk(dev_priv);
> +	intel_dump_cdclk_state(&dev_priv->cdclk.hw, "Current CDCLK");
>  	dev_priv->cdclk.logical = dev_priv->cdclk.actual = dev_priv->cdclk.hw;
>  
>  	intel_init_clock_gating(dev_priv);
> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
> index 3de8d98baed7..3b4eafd39f55 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -1336,6 +1336,8 @@ bool intel_cdclk_changed(const struct intel_cdclk_state *a,
>  			 const struct intel_cdclk_state *b);
>  void intel_set_cdclk(struct drm_i915_private *dev_priv,
>  		     const struct intel_cdclk_state *cdclk_state);
> +void intel_dump_cdclk_state(const struct intel_cdclk_state *cdclk_state,
> +			    const char *context);
>  
>  /* intel_display.c */
>  void i830_enable_pipe(struct drm_i915_private *dev_priv, enum pipe pipe);
> -- 
> 2.13.6
>