[Intel-gfx] [PATCH 11/11] [v3] drm/i915: Add intel_compare_color_lut() to compare hw and sw gamma lut values

[Jani Nikula]

On Mon, 15 Apr 2019, Swati Sharma <swati2.sharma at intel.com> wrote:
> v3: Rebase
>
> Signed-off-by: Swati Sharma <swati2.sharma at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_color.c   | 49 ++++++++++++++++++++++++++++++++++++
>  drivers/gpu/drm/i915/intel_color.h   |  6 +++++
>  drivers/gpu/drm/i915/intel_display.c | 10 ++++++++
>  3 files changed, 65 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/intel_color.c b/drivers/gpu/drm/i915/intel_color.c
> index e2703f9..867c1de 100644
> --- a/drivers/gpu/drm/i915/intel_color.c
> +++ b/drivers/gpu/drm/i915/intel_color.c
> @@ -1500,6 +1500,55 @@ static void ilk_get_color_config(struct intel_crtc_state *crtc_state)
>  		ilk_get_gamma_config(crtc_state);
>  }
>  
> +static inline bool gamma_err_check(struct drm_color_lut *sw_lut, struct drm_color_lut *hw_lut, u32 err)
> +{
> +	 return ((abs((long)hw_lut->red - sw_lut->red)) >= err) ||
> +	        ((abs((long)hw_lut->blue - sw_lut->blue)) >= err) ||
> +	        ((abs((long)hw_lut->green - sw_lut->green)) >= err);
> +}
> +
> +bool intel_compare_color_lut(struct drm_property_blob *blob1,
> +			     struct drm_property_blob *blob2,
> +			     u32 gamma_mode)

Please prefix the function name with intel_color_ like I mentioned
earlier in the series.

I don't think it's obvious what a boolean function called "compare"
should return. I see intel_compare_link_m_n() and
intel_compare_infoframe() I think they're equally bad.

intel_color_lut_match() or intel_color_lut_equal() would be obvious.

The C strcmp() is the notorious example where 0 means equal.

> +{
> +	struct drm_color_lut *sw_lut = blob1->data;
> +	struct drm_color_lut *hw_lut = blob2->data;
> +	int sw_lut_size, hw_lut_size, i;
> +	u32 bit_precision, err;
> +
> +	if (!blob1 || !blob2)
> +		return false;
> +
> +	switch(gamma_mode) {
> +	case GAMMA_MODE_MODE_8BIT:
> +		bit_precision = 8;
> +		break;
> +	case GAMMA_MODE_MODE_10BIT:
> +		bit_precision = 10;
> +		break;
> +	case GAMMA_MODE_MODE_12BIT:
> +		bit_precision = 12;
> +		break;
> +	default:

It's customary to just add the default label above the correct label
above.

BR,
Jani.

> +		bit_precision = 8;
> +	}
> +
> +	err = 0xffff >> bit_precision;
> +
> +	sw_lut_size = drm_color_lut_size(blob1);
> +	hw_lut_size = drm_color_lut_size(blob2);
> +
> +	if (sw_lut_size != hw_lut_size)
> +		return false;
> +
> +	for (i = 0; i < sw_lut_size; i++) {
> +		 if (!gamma_err_check(&hw_lut[i], &sw_lut[i], err))
> +			return false;
> +	}
> +
> +	return true;
> +}
> +
>  void intel_color_init(struct intel_crtc *crtc)
>  {
>  	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
> diff --git a/drivers/gpu/drm/i915/intel_color.h b/drivers/gpu/drm/i915/intel_color.h
> index 7ca304f..575003f 100644
> --- a/drivers/gpu/drm/i915/intel_color.h
> +++ b/drivers/gpu/drm/i915/intel_color.h
> @@ -6,13 +6,19 @@
>  #ifndef __INTEL_COLOR_H__
>  #define __INTEL_COLOR_H__
>  
> +#include <linux/types.h>
> +
>  struct intel_crtc_state;
>  struct intel_crtc;
> +struct drm_property_blob;
>  
>  void intel_color_init(struct intel_crtc *crtc);
>  int intel_color_check(struct intel_crtc_state *crtc_state);
>  void intel_color_commit(const struct intel_crtc_state *crtc_state);
>  void intel_color_load_luts(const struct intel_crtc_state *crtc_state);
>  void intel_get_color_config(struct intel_crtc_state *crtc_state);
> +bool intel_compare_color_lut(struct drm_property_blob *blob1,
> +			     struct drm_property_blob *blob2,
> +			     u32 gamma_mode);
>  
>  #endif /* __INTEL_COLOR_H__ */
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 0fc9dab..b074f00 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -12236,6 +12236,14 @@ static bool fastboot_enabled(struct drm_i915_private *dev_priv)
>  	} \
>  } while (0)
>  
> +#define PIPE_CONF_CHECK_COLOR_LUT(name, gamma_mode) do { \
> +	if (!intel_compare_color_lut(current_config->name, pipe_config->name, gamma_mode)) { \
> +		pipe_config_err(adjust, __stringify(name), \
> +				"hw_state doesn't match sw_state\n"); \
> +		ret = false; \
> +	} \
> +} while (0)
> +
>  #define PIPE_CONF_QUIRK(quirk) \
>  	((current_config->quirks | pipe_config->quirks) & (quirk))
>  
> @@ -12379,6 +12387,8 @@ static bool fastboot_enabled(struct drm_i915_private *dev_priv)
>  	PIPE_CONF_CHECK_INFOFRAME(spd);
>  	PIPE_CONF_CHECK_INFOFRAME(hdmi);
>  
> +	PIPE_CONF_CHECK_COLOR_LUT(base.gamma_lut, pipe_config->gamma_mode);
> +
>  #undef PIPE_CONF_CHECK_X
>  #undef PIPE_CONF_CHECK_I
>  #undef PIPE_CONF_CHECK_BOOL

-- 
Jani Nikula, Intel Open Source Graphics Center