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 7:29 PM, Souza, Jose wrote:
> On Fri, 2021-09-10 at 16:38 +0300, Gwan-gyeong Mun wrote:
>>
>> 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"?
> 
> It was made sure that all alderlake-P BOM panels will have 1-based X granularity, I can add something like that.
> 
> 
>>> +
>>>    /*
>>>     * 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_CONTROLREG_BIT(25) /* GLK */
>>>    #define  FECSTALL_DIS_DPTSTREAM_DPTTGREG_BIT(23)
>>>    #define  DDI_TRAINING_OVERRIDE_ENABLEREG_BIT(19)
>>> +#define  D13_1_BASED_X_GRANULARITYREG_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.
> 
> The name of registers are set to match specification name as close as possible not the use or meaning.
Yes, just looking at the macro, I thought that it could be interpreted 
in two ways: D13 / 1_BASED_X_GRANULARITY or D13_1 / BASED_X_GRANULARITY.
If our macro naming convention is fine in this case, then I don't think 
the code is the problem either.
> 
>>>    #define  DDI_TRAINING_OVERRIDE_VALUEREG_BIT(18)
>>>    #define  DDIE_TRAINING_OVERRIDE_ENABLEREG_BIT(17) /* CHICKEN_TRANS_A only */
>>>    #define  DDIE_TRAINING_OVERRIDE_VALUEREG_BIT(16) /* CHICKEN_TRANS_A only */
>>> @@ -12789,4 +12790,7 @@ enum skl_power_gate {
>>>    #define CLKREQ_POLICY_MMIO(0x101038)
>>>    #define  CLKREQ_POLICY_MEM_UP_OVRDREG_BIT(1)
>>>
>>> +#define CLKGATE_DIS_MISC_MMIO(0x46534)
>>> +#define  CLKGATE_DIS_MISC_DMASC_GATING_DISREG_BIT(21)
>>> +
>>>    #endif /* _I915_REG_H_ */
>>>
>