Re: [Intel-gfx] [PATCH 3/3] drm/i915: Use REG_FIELD_GET() to extract skl+ wm latencies

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

On Thu, 08 Sep 2022, Ville Syrjala <ville.syrjala@linux.intel.com> wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> Replace the hand rolled stuff with REG_FIELD_GET() for reading
> out the skl+ watermark latencies.
>
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

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

> ---
>  drivers/gpu/drm/i915/display/skl_watermark.c | 22 +++++++-------------
>  drivers/gpu/drm/i915/i915_reg.h              |  8 +++----
>  2 files changed, 12 insertions(+), 18 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/skl_watermark.c b/drivers/gpu/drm/i915/display/skl_watermark.c
> index 25ca92ae8958..cb297725d5b9 100644
> --- a/drivers/gpu/drm/i915/display/skl_watermark.c
> +++ b/drivers/gpu/drm/i915/display/skl_watermark.c
> @@ -3239,13 +3239,10 @@ static void skl_read_wm_latency(struct drm_i915_private *i915, u16 wm[])
>  		return;
>  	}
>  
> -	wm[0] = (val & GEN9_MEM_LATENCY_LEVEL_MASK) * mult;
> -	wm[1] = ((val >> GEN9_MEM_LATENCY_LEVEL_1_5_SHIFT) &
> -		 GEN9_MEM_LATENCY_LEVEL_MASK) * mult;
> -	wm[2] = ((val >> GEN9_MEM_LATENCY_LEVEL_2_6_SHIFT) &
> -		 GEN9_MEM_LATENCY_LEVEL_MASK) * mult;
> -	wm[3] = ((val >> GEN9_MEM_LATENCY_LEVEL_3_7_SHIFT) &
> -		 GEN9_MEM_LATENCY_LEVEL_MASK) * mult;
> +	wm[0] = REG_FIELD_GET(GEN9_MEM_LATENCY_LEVEL_0_4_MASK, val) * mult;
> +	wm[1] = REG_FIELD_GET(GEN9_MEM_LATENCY_LEVEL_1_5_MASK, val) * mult;
> +	wm[2] = REG_FIELD_GET(GEN9_MEM_LATENCY_LEVEL_2_6_MASK, val) * mult;
> +	wm[3] = REG_FIELD_GET(GEN9_MEM_LATENCY_LEVEL_3_7_MASK, val) * mult;
>  
>  	/* read the second set of memory latencies[4:7] */
>  	val = 1; /* data0 to be programmed to 1 for second set */
> @@ -3255,13 +3252,10 @@ static void skl_read_wm_latency(struct drm_i915_private *i915, u16 wm[])
>  		return;
>  	}
>  
> -	wm[4] = (val & GEN9_MEM_LATENCY_LEVEL_MASK) * mult;
> -	wm[5] = ((val >> GEN9_MEM_LATENCY_LEVEL_1_5_SHIFT) &
> -		 GEN9_MEM_LATENCY_LEVEL_MASK) * mult;
> -	wm[6] = ((val >> GEN9_MEM_LATENCY_LEVEL_2_6_SHIFT) &
> -		 GEN9_MEM_LATENCY_LEVEL_MASK) * mult;
> -	wm[7] = ((val >> GEN9_MEM_LATENCY_LEVEL_3_7_SHIFT) &
> -		 GEN9_MEM_LATENCY_LEVEL_MASK) * mult;
> +	wm[4] = REG_FIELD_GET(GEN9_MEM_LATENCY_LEVEL_0_4_MASK, val) * mult;
> +	wm[5] = REG_FIELD_GET(GEN9_MEM_LATENCY_LEVEL_1_5_MASK, val) * mult;
> +	wm[6] = REG_FIELD_GET(GEN9_MEM_LATENCY_LEVEL_2_6_MASK, val) * mult;
> +	wm[7] = REG_FIELD_GET(GEN9_MEM_LATENCY_LEVEL_3_7_MASK, val) * mult;
>  
>  	adjust_wm_latency(i915, wm, max_level, read_latency);
>  }
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index c413eec3373f..7289e2b7da2c 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -6551,10 +6551,10 @@
>  #define     GEN6_DECODE_RC6_VID(vids)		(((vids) * 5) + 245)
>  #define   BDW_PCODE_DISPLAY_FREQ_CHANGE_REQ	0x18
>  #define   GEN9_PCODE_READ_MEM_LATENCY		0x6
> -#define     GEN9_MEM_LATENCY_LEVEL_MASK		0xFF
> -#define     GEN9_MEM_LATENCY_LEVEL_1_5_SHIFT	8
> -#define     GEN9_MEM_LATENCY_LEVEL_2_6_SHIFT	16
> -#define     GEN9_MEM_LATENCY_LEVEL_3_7_SHIFT	24
> +#define     GEN9_MEM_LATENCY_LEVEL_3_7_MASK	REG_GENMASK(31, 24)
> +#define     GEN9_MEM_LATENCY_LEVEL_2_6_MASK	REG_GENMASK(23, 16)
> +#define     GEN9_MEM_LATENCY_LEVEL_1_5_MASK	REG_GENMASK(15, 8)
> +#define     GEN9_MEM_LATENCY_LEVEL_0_4_MASK	REG_GENMASK(7, 0)
>  #define   SKL_PCODE_LOAD_HDCP_KEYS		0x5
>  #define   SKL_PCODE_CDCLK_CONTROL		0x7
>  #define     SKL_CDCLK_PREPARE_FOR_CHANGE	0x3

-- 
Jani Nikula, Intel Open Source Graphics Center