[Intel-gfx] [v4] drm/i915/pps: improve eDP power on flow

[Lee, Shawn C]

On Wednesday, November 16, 2022 11:45 PM, Jani Nikula <jani.nikula at linux.intel.com> wrote:
>On Mon, 14 Nov 2022, Lee Shawn C <shawn.c.lee at intel.com> wrote:
>> After i915 dirver initialized, a panel power off cycle delay always 
>> append before turn eDP on. If eDP display did not power on before. 
>> With this change, power off duration might longer than power cycle 
>> delay. So driver can save power cycle delay to speed up driver 
>> initialization time.
>>
>> v2: fix commit messages
>> v3: refine panel_power_off_time default value and modify
>>     commit messages
>> v4: add eDP power off cycle delay at the path to unload i915 module
>>
>> Cc: Shankar Uma <uma.shankar at intel.com>
>> Cc: Jani Nikula <jani.nikula at linux.intel.com>
>> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
>> Signed-off-by: Lee Shawn C <shawn.c.lee at intel.com>
>> ---
>>  drivers/gpu/drm/i915/display/intel_pps.c | 2 +-
>>  drivers/gpu/drm/i915/i915_driver.c       | 4 ++++
>>  2 files changed, 5 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/i915/display/intel_pps.c 
>> b/drivers/gpu/drm/i915/display/intel_pps.c
>> index 81ee7f3aadf6..ab4118b38120 100644
>> --- a/drivers/gpu/drm/i915/display/intel_pps.c
>> +++ b/drivers/gpu/drm/i915/display/intel_pps.c
>> @@ -1100,7 +1100,7 @@ bool intel_pps_have_panel_power_or_vdd(struct 
>> intel_dp *intel_dp)
>>  
>>  static void pps_init_timestamps(struct intel_dp *intel_dp)  {
>> -	intel_dp->pps.panel_power_off_time = ktime_get_boottime();
>> +	intel_dp->pps.panel_power_off_time = 0;
>>  	intel_dp->pps.last_power_on = jiffies;
>>  	intel_dp->pps.last_backlight_off = jiffies;  } diff --git 
>> a/drivers/gpu/drm/i915/i915_driver.c 
>> b/drivers/gpu/drm/i915/i915_driver.c
>> index c3d43f9b1e45..0e3cbd129055 100644
>> --- a/drivers/gpu/drm/i915/i915_driver.c
>> +++ b/drivers/gpu/drm/i915/i915_driver.c
>> @@ -107,6 +107,8 @@ static const char irst_name[] = "INT3392";
>>  
>>  static const struct drm_driver i915_drm_driver;
>>  
>> +static void intel_shutdown_encoders(struct drm_i915_private 
>> +*dev_priv);
>> +
>>  static void i915_release_bridge_dev(struct drm_device *dev,
>>  				    void *bridge)
>>  {
>> @@ -796,6 +798,8 @@ static void i915_driver_unregister(struct 
>> drm_i915_private *dev_priv)
>>  
>>  	intel_display_driver_unregister(dev_priv);
>>  
>> +	intel_shutdown_encoders(dev_priv);
>> +
>
>Per Ville's comments on IRC, this is still too early. See [1] for another approach.
>
>BR,
>Jani.
>

Thank you! I've tested this patch and it works properly. Detail kernel log is attached on [2].
Please help to review and merge that patch ASAP. 

Best regards,
Shawn

>
>[1] https://patchwork.freedesktop.org/patch/msgid/20221116150657.1347504-1-jani.nikula@intel.com

[2] https://gitlab.freedesktop.org/drm/intel/-/issues/7417#note_1643009

>
>
>>  	for_each_gt(gt, dev_priv, i)
>>  		intel_gt_driver_unregister(gt);
>
>--
>Jani Nikula, Intel Open Source Graphics Center