[Intel-gfx] [PATCH v3] drm/i915/edp: Add a T12 panel delay quirk to fix DP AUX CH timeouts

[Jani Nikula]

On Fri, 30 Jun 2017, Ville Syrjälä <ville.syrjala at linux.intel.com> wrote:
> On Thu, Jun 29, 2017 at 02:10:38PM -0700, Manasi Navare wrote:
>> This patch fixes the DP AUX CH timeouts observed during CI IGT
>> tests thus fixing the CI failures. This is done by adding a
>> quirk for a particular PCI device that requires the panel power
>> cycle delay (T12) to be set to 800ms which is 300msecs more than
>> the minimum value specified in the eDP spec. So a quirk is
>> implemented for that specific PCI device.
>> 
>> v3:
>> * Change some comments, specify the delay as 800 * 10 (Ville)
>> v2:
>> * Change the function and variable names to from PPS_T12_
>> to _T12 since it is a T12 delay (Clint)
>> 
>> Fixes: FDO #101144 #101515 #101154 #101167
>
> That's not how we do it.

Indeed.

Fixes: is used to indicate another commit that this patch fixes. See
Documentation/process/submitting-patches.rst. Does one exist here?

Bugzilla links are tagged using:

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101144
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101154
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101167
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101515

See git log for examples.

BR,
Jani.

>
> Also please look into git send-email --in-reply-to option. Review is
> easier if the patches aren't spread all over the mailbox.
>
>> Cc: Ville Syrjala <ville.syrjala at linux.intel.com>
>> Cc: Clinton Taylor <clinton.a.taylor at intel.com>
>> Signed-off-by: Manasi Navare <manasi.d.navare at intel.com>
>> Reviewed-by: Clinton Taylor <clinton.a.taylor at intel.com>
>> ---
>>  drivers/gpu/drm/i915/i915_drv.h      |  1 +
>>  drivers/gpu/drm/i915/intel_display.c | 14 ++++++++++++++
>>  drivers/gpu/drm/i915/intel_dp.c      | 11 +++++++++++
>>  3 files changed, 26 insertions(+)
>> 
>> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
>> index 427d10c..4327c8a 100644
>> --- a/drivers/gpu/drm/i915/i915_drv.h
>> +++ b/drivers/gpu/drm/i915/i915_drv.h
>> @@ -1168,6 +1168,7 @@ enum intel_sbi_destination {
>>  #define QUIRK_INVERT_BRIGHTNESS (1<<2)
>>  #define QUIRK_BACKLIGHT_PRESENT (1<<3)
>>  #define QUIRK_PIN_SWIZZLED_PAGES (1<<5)
>> +#define QUIRK_INCREASE_T12_DELAY (1<<6)
>>  
>>  struct intel_fbdev;
>>  struct intel_fbc_work;
>> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
>> index 4e03ca6..87dfde9 100644
>> --- a/drivers/gpu/drm/i915/intel_display.c
>> +++ b/drivers/gpu/drm/i915/intel_display.c
>> @@ -14765,6 +14765,17 @@ static void quirk_backlight_present(struct drm_device *dev)
>>  	DRM_INFO("applying backlight present quirk\n");
>>  }
>>  
>> +/* Toshiba Satellite P50-C-18C requires T12 delay to be min 800ms
>> + * which is 300 ms greater than eDP spec T12 min.
>> + */
>> +static void quirk_increase_t12_delay(struct drm_device *dev)
>> +{
>> +	struct drm_i915_private *dev_priv = to_i915(dev);
>> +
>> +	dev_priv->quirks |= QUIRK_INCREASE_T12_DELAY;
>> +	DRM_INFO("Applying T12 delay quirk\n");
>> +}
>> +
>>  struct intel_quirk {
>>  	int device;
>>  	int subsystem_vendor;
>> @@ -14848,6 +14859,9 @@ static struct intel_quirk intel_quirks[] = {
>>  
>>  	/* Dell Chromebook 11 (2015 version) */
>>  	{ 0x0a16, 0x1028, 0x0a35, quirk_backlight_present },
>> +
>> +	/* Toshiba Satellite P50-C-18C */
>> +	{ 0x191B, 0x1179, 0xF840, quirk_increase_t12_delay },
>>  };
>>  
>>  static void intel_init_quirks(struct drm_device *dev)
>> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
>> index 67bc8a7a..4d7e510 100644
>> --- a/drivers/gpu/drm/i915/intel_dp.c
>> +++ b/drivers/gpu/drm/i915/intel_dp.c
>> @@ -5230,6 +5230,17 @@ intel_dp_init_panel_power_sequencer(struct drm_device *dev,
>>  	intel_pps_dump_state("cur", &cur);
>>  
>>  	vbt = dev_priv->vbt.edp.pps;
>> +	/* On Toshiba Satellite P50-C-18C system the VBT T12 delay
>> +	 * of 500ms appears to be too short. Ocassionally the panel
>> +	 * just fails to power back on. Increasing the delay to 800ms
>> +	 * seems sufficient to avpid this problem.a
>                                  ^
> typo
>
> Otherwise looks OK to me.
>
>> +	 */
>> +	if (dev_priv->quirks & QUIRK_INCREASE_T12_DELAY) {
>> +
>> +		vbt.t11_t12 = max_t(u16, vbt.t11_t12, 800 * 10);
>> +		DRM_DEBUG_KMS("Increasing T12 panel delay as per the quirk to %d\n",
>> +			      vbt.t11_t12);
>> +	}
>>  	/* T11_T12 delay is special and actually in units of 100ms, but zero
>>  	 * based in the hw (so we need to add 100 ms). But the sw vbt
>>  	 * table multiplies it with 1000 to make it in units of 100usec,
>> -- 
>> 2.1.4

-- 
Jani Nikula, Intel Open Source Technology Center