[Intel-gfx] [PATCH 5/5] drm/i915/psr: Display WA #1130: bxt, glk

[Pandiyan, Dhinakaran]

On Tue, 2018-02-13 at 15:26 -0800, Rodrigo Vivi wrote:
> Host/Render modifications do not trigger PSR exit
> or Wireless quick capture exit correctly.
> 

I don't get this workaround either. The wording indicates frontbuffer
modifications are expected to trigger PSR exit in HW. But we rely on the
driver's frontbuffer tracking to do that for us.



> WA: Set MMIO register 0x4653C bit 31 = 1b.
> 
> Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
> Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
> ---
>  drivers/gpu/drm/i915/i915_reg.h | 1 +
>  drivers/gpu/drm/i915/intel_pm.c | 7 +++++++
>  2 files changed, 8 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index 0f423cd52983..8a4cd8b4bd7c 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -3924,6 +3924,7 @@ enum {
>  #define   PWM1_GATING_DIS		(1 << 13)
>  
>  #define GEN9_CLKGATE_DIS_4		_MMIO(0x4653C)
> +#define   BXT_DCIPH_GATING_DIS		(1 << 31)
>  #define   BXT_GMBUS_GATING_DIS		(1 << 14)
>  
>  #define _CLKGATE_DIS_PSL_A		0x46520
> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> index 7e15b261821d..a0a6b4b7c47b 100644
> --- a/drivers/gpu/drm/i915/intel_pm.c
> +++ b/drivers/gpu/drm/i915/intel_pm.c
> @@ -114,6 +114,10 @@ static void bxt_init_clock_gating(struct drm_i915_private *dev_priv)
>  	 */
>  	I915_WRITE(GEN9_CLKGATE_DIS_0, I915_READ(GEN9_CLKGATE_DIS_0) |
>  		   PWM1_GATING_DIS | PWM2_GATING_DIS);
> +
> +	/* Display WA #1130:bxt */
> +	I915_WRITE(GEN9_CLKGATE_DIS_4, I915_READ(GEN9_CLKGATE_DIS_4) |
> +		   BXT_DCIPH_GATING_DIS);
>  }
>  
>  static void glk_init_clock_gating(struct drm_i915_private *dev_priv)
> @@ -137,6 +141,9 @@ static void glk_init_clock_gating(struct drm_i915_private *dev_priv)
>  		I915_WRITE(CHICKEN_MISC_2, val);
>  	}
>  
> +	/* Display WA #1130:glk */
> +	I915_WRITE(GEN9_CLKGATE_DIS_4, I915_READ(GEN9_CLKGATE_DIS_4) |
> +		   BXT_DCIPH_GATING_DIS);
>  }
>  
>  static void i915_pineview_get_mem_freq(struct drm_i915_private *dev_priv)