Re: [Intel-gfx] [PATCH 2/5] drm/i915/display/adlp: Add new PSR2 workarounds

[Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>]

On 9/10/21 2:07 AM, José Roberto de Souza wrote:
> Wa_16014451276 fixes the starting coordinate for PSR2 selective
> updates. CHICKEN_TRANS definition of the workaround bit has a wrong
> name based on workaround definition and HSD.
> 
> Wa_14014971508 allows the screen to continue to be updated when
> coming back from DC5/DC6 and SF_SINGLE_FULL_FRAME bit is not kept
> set in PSR2_MAN_TRK_CTL.
> 
> Wa_16012604467 fixes underruns when exiting PSR2 when it is in one
> of its internal states.
> 
> Wa_14014971508 is still in pending status in BSpec but by
> the time this is reviewed and ready to be merged it will be finalized.
> 
> BSpec: 54369
> BSpec: 50054
> Cc: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
> Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
> ---
>   drivers/gpu/drm/i915/display/intel_psr.c | 23 ++++++++++++++++++++++-
>   drivers/gpu/drm/i915/i915_reg.h          |  4 ++++
>   2 files changed, 26 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
> index 36816abb3bcc0..92c0b2159559f 100644
> --- a/drivers/gpu/drm/i915/display/intel_psr.c
> +++ b/drivers/gpu/drm/i915/display/intel_psr.c
> @@ -1086,6 +1086,12 @@ static void intel_psr_enable_source(struct intel_dp *intel_dp)
>   		intel_de_write(dev_priv, reg, chicken);
>   	}
>   
> +	/* Wa_16014451276:adlp */
> +	if (IS_ALDERLAKE_P(dev_priv) &&
> +	    intel_dp->psr.psr2_enabled)
> +		intel_de_rmw(dev_priv, CHICKEN_TRANS(cpu_transcoder), 0,
> +			     D13_1_BASED_X_GRANULARITY);
Depending on the capability of the PSR panel, the following setting may 
not be necessary, could you add some comments such as "force enable 
1-based X granularity on PSR2 VSC SDP"?
> +
>   	/*
>   	 * Per Spec: Avoid continuous PSR exit by masking MEMUP and HPD also
>   	 * mask LPSP to avoid dependency on other drivers that might block
> @@ -1131,6 +1137,11 @@ static void intel_psr_enable_source(struct intel_dp *intel_dp)
>   			     TRANS_SET_CONTEXT_LATENCY(intel_dp->psr.transcoder),
>   			     TRANS_SET_CONTEXT_LATENCY_MASK,
>   			     TRANS_SET_CONTEXT_LATENCY_VALUE(1));
> +
> +	/* Wa_16012604467:adlp */
> +	if (IS_ALDERLAKE_P(dev_priv) && intel_dp->psr.psr2_enabled)
> +		intel_de_rmw(dev_priv, CLKGATE_DIS_MISC, 0,
> +			     CLKGATE_DIS_MISC_DMASC_GATING_DIS);
>   }
>   
>   static bool psr_interrupt_error_check(struct intel_dp *intel_dp)
> @@ -1320,6 +1331,11 @@ static void intel_psr_disable_locked(struct intel_dp *intel_dp)
>   			     TRANS_SET_CONTEXT_LATENCY(intel_dp->psr.transcoder),
>   			     TRANS_SET_CONTEXT_LATENCY_MASK, 0);
>   
> +	/* Wa_16012604467:adlp */
> +	if (IS_ALDERLAKE_P(dev_priv) && intel_dp->psr.psr2_enabled)
> +		intel_de_rmw(dev_priv, CLKGATE_DIS_MISC,
> +			     CLKGATE_DIS_MISC_DMASC_GATING_DIS, 0);
> +
>   	intel_snps_phy_update_psr_power_state(dev_priv, phy, false);
>   
>   	/* Disable PSR on Sink */
> @@ -1488,8 +1504,13 @@ static void psr2_man_trk_ctl_calc(struct intel_crtc_state *crtc_state,
>   	u32 val = PSR2_MAN_TRK_CTL_ENABLE;
>   
>   	if (full_update) {
> +		/*
> +		 * Wa_14014971508:adlp
> +		 * SINGLE_FULL_FRAME bit is not hold in register so can not be
> +		 * restored by DMC, so using CONTINUOS_FULL_FRAME to mimic that
> +		 */
>   		if (IS_ALDERLAKE_P(dev_priv))
> -			val |= ADLP_PSR2_MAN_TRK_CTL_SF_SINGLE_FULL_FRAME;
> +			val |= ADLP_PSR2_MAN_TRK_CTL_SF_CONTINUOS_FULL_FRAME;
>   		else
>   			val |= PSR2_MAN_TRK_CTL_SF_SINGLE_FULL_FRAME;
>   
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index c2853cc005ee6..0de2f7541da6c 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -8235,6 +8235,7 @@ enum {
>   #define  VSC_DATA_SEL_SOFTWARE_CONTROL	REG_BIT(25) /* GLK */
>   #define  FECSTALL_DIS_DPTSTREAM_DPTTG	REG_BIT(23)
>   #define  DDI_TRAINING_OVERRIDE_ENABLE	REG_BIT(19)
> +#define  D13_1_BASED_X_GRANULARITY	REG_BIT(18)
The meaning of this macro is to set "force enable 1-based X granularity 
on PSR2 VSC SDP" in Display 13.1 ADL, so the meaning of the macro may be 
a little ambiguous.
>   #define  DDI_TRAINING_OVERRIDE_VALUE	REG_BIT(18)
>   #define  DDIE_TRAINING_OVERRIDE_ENABLE	REG_BIT(17) /* CHICKEN_TRANS_A only */
>   #define  DDIE_TRAINING_OVERRIDE_VALUE	REG_BIT(16) /* CHICKEN_TRANS_A only */
> @@ -12789,4 +12790,7 @@ enum skl_power_gate {
>   #define CLKREQ_POLICY			_MMIO(0x101038)
>   #define  CLKREQ_POLICY_MEM_UP_OVRD	REG_BIT(1)
>   
> +#define CLKGATE_DIS_MISC			_MMIO(0x46534)
> +#define  CLKGATE_DIS_MISC_DMASC_GATING_DIS	REG_BIT(21)
> +
>   #endif /* _I915_REG_H_ */
>