Re: [Intel-gfx] [PATCH 2/2] drm/i915/debugfs: add crtc i915_pipe debugfs file

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

On Fri, 17 Mar 2023, Ville Syrjälä <ville.syrjala@linux.intel.com> wrote:
> On Fri, Mar 17, 2023 at 02:53:52PM +0200, Jani Nikula wrote:
>> The pipe may differ from crtc index if pipes are fused off. For testing
>> purposes, IGT needs to know the pipe.
>> 
>> There's already a I915_GET_PIPE_FROM_CRTC_ID IOCTL for this. However,
>> the upcoming Xe driver won't have that IOCTL, and going forward, we'll
>> want a unified interface for testing i915 and Xe, as they share the
>> display code. Thus add the debugfs for i915 display.
>> 
>> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
>> ---
>>  .../gpu/drm/i915/display/intel_display_debugfs.c    | 13 +++++++++++++
>>  1 file changed, 13 insertions(+)
>> 
>> diff --git a/drivers/gpu/drm/i915/display/intel_display_debugfs.c b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
>> index faa44fb80aac..e85270adca95 100644
>> --- a/drivers/gpu/drm/i915/display/intel_display_debugfs.c
>> +++ b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
>> @@ -1657,6 +1657,17 @@ static int i915_current_bpc_show(struct seq_file *m, void *data)
>>  }
>>  DEFINE_SHOW_ATTRIBUTE(i915_current_bpc);
>>  
>> +/* Pipe may differ from crtc index if pipes are fused off */
>> +static int intel_crtc_pipe_show(struct seq_file *m, void *unused)
>> +{
>> +	struct intel_crtc *crtc = m->private;
>> +
>> +	seq_printf(m, "%d\n", crtc->pipe);
>
> Are we happy with an integer or should we use the actual alphabetic
> name here?

Primarily I considered the programmatic use case, and the ease of
switching over from the ioctl. What do we gain by making IGT parse this?

> Either way, the series is:
> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

Thanks,
Jani.

>
>> +
>> +	return 0;
>> +}
>> +DEFINE_SHOW_ATTRIBUTE(intel_crtc_pipe);
>> +
>>  /**
>>   * intel_connector_debugfs_add - add i915 specific connector debugfs files
>>   * @connector: pointer to a registered drm_connector
>> @@ -1735,4 +1746,6 @@ void intel_crtc_debugfs_add(struct intel_crtc *crtc)
>>  
>>  	debugfs_create_file("i915_current_bpc", 0444, root, crtc,
>>  			    &i915_current_bpc_fops);
>> +	debugfs_create_file("i915_pipe", 0444, root, crtc,
>> +			    &intel_crtc_pipe_fops);
>>  }
>> -- 
>> 2.39.2

-- 
Jani Nikula, Intel Open Source Graphics Center