Re: [PATCH v2 11/13] drm/i915/vrr: Add state checker for dc balance params

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

On Wed, 23 Apr 2025, "Nautiyal, Ankit K" <ankit.k.nautiyal@intel.com> wrote:
> On 4/21/2025 9:18 PM, Mitul Golani wrote:
>> Add state checker for dc balance params. Also add macro to
>> check source support.
>>
>> Signed-off-by: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com>
>> ---
>>   drivers/gpu/drm/i915/display/intel_display.c |  7 +++++++
>>   drivers/gpu/drm/i915/display/intel_vrr.c     | 20 +++++++++++++++++++-
>>   2 files changed, 26 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
>> index 274d01552ccf..4a21acb88aa7 100644
>> --- a/drivers/gpu/drm/i915/display/intel_display.c
>> +++ b/drivers/gpu/drm/i915/display/intel_display.c
>> @@ -5402,6 +5402,13 @@ intel_pipe_config_compare(const struct intel_crtc_state *current_config,
>>   		PIPE_CONF_CHECK_LLI(cmrr.cmrr_m);
>>   		PIPE_CONF_CHECK_LLI(cmrr.cmrr_n);
>>   		PIPE_CONF_CHECK_BOOL(cmrr.enable);
>> +		PIPE_CONF_CHECK_I(vrr.dc_balance.vmin);
> Add check for vrr.dc_balance.enable?

They should match regardless, no? Something's wrong if they differ.

>> +		PIPE_CONF_CHECK_I(vrr.dc_balance.vmax);
>> +		PIPE_CONF_CHECK_I(vrr.dc_balance.guardband);
>> +		PIPE_CONF_CHECK_I(vrr.dc_balance.slope);
>> +		PIPE_CONF_CHECK_I(vrr.dc_balance.max_increase);
>> +		PIPE_CONF_CHECK_I(vrr.dc_balance.max_decrease);
>> +		PIPE_CONF_CHECK_I(vrr.dc_balance.vblank_target);
>>   	}
>>   
>>   	if (!fastset || intel_vrr_always_use_vrr_tg(display)) {
>> diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c b/drivers/gpu/drm/i915/display/intel_vrr.c
>> index fb96d03bbf03..e8802348e5fa 100644
>> --- a/drivers/gpu/drm/i915/display/intel_vrr.c
>> +++ b/drivers/gpu/drm/i915/display/intel_vrr.c
>> @@ -740,7 +740,7 @@ void intel_vrr_get_config(struct intel_crtc_state *crtc_state)
>>   {
>>   	struct intel_display *display = to_intel_display(crtc_state);
>>   	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
>> -	u32 trans_vrr_ctl, trans_vrr_vsync;
>> +	u32 trans_vrr_ctl, trans_vrr_vsync, dcb_ctl;
>>   	bool vrr_enable;
>>   
>>   	trans_vrr_ctl = intel_de_read(display,
>> @@ -802,6 +802,24 @@ void intel_vrr_get_config(struct intel_crtc_state *crtc_state)
>>   	else
>>   		crtc_state->vrr.enable = vrr_enable;
>>   
>> +	if (HAS_DC_BALANCE(display)) {
>> +		dcb_ctl = intel_de_read(display, PIPEDMC_DCB_CTL(display, cpu_transcoder));
>
> dsb_ctl is not used. Need to use it for vrr.dc_balance.enable.
>
>
> IMO we can introduce the new members (which is done in Patch#4), readout 
> and state checker in one patch.
>
> Regards,
>
> Ankit
>
>
>> +		crtc_state->vrr.dc_balance.vmin =
>> +			intel_de_read(display, PIPEDMC_DCB_VMIN(display, cpu_transcoder)) + 1;
>> +		crtc_state->vrr.dc_balance.vmax =
>> +			intel_de_read(display, PIPEDMC_DCB_VMAX(display, cpu_transcoder)) + 1;
>> +		crtc_state->vrr.dc_balance.guardband =
>> +			intel_de_read(display, PIPEDMC_DCB_GUARDBAND(display, cpu_transcoder));
>> +		crtc_state->vrr.dc_balance.max_increase =
>> +			intel_de_read(display, PIPEDMC_DCB_MAX_INCREASE(display, cpu_transcoder));
>> +		crtc_state->vrr.dc_balance.max_decrease =
>> +			intel_de_read(display, PIPEDMC_DCB_MAX_DECREASE(display, cpu_transcoder));
>> +		crtc_state->vrr.dc_balance.slope =
>> +			intel_de_read(display, PIPEDMC_DCB_SLOPE(display, cpu_transcoder));
>> +		crtc_state->vrr.dc_balance.vblank_target =
>> +			intel_de_read(display, PIPEDMC_DCB_VBLANK(display, cpu_transcoder));
>> +	}
>> +
>>   	/*
>>   	 * #TODO: For Both VRR and CMRR the flag I915_MODE_FLAG_VRR is set for mode_flags.
>>   	 * Since CMRR is currently disabled, set this flag for VRR for now.

-- 
Jani Nikula, Intel