> -----Original Message-----
> From: Nikula, Jani <jani.nikula@xxxxxxxxx>
> Sent: Monday, February 24, 2025 4:26 PM
> To: Manna, Animesh <animesh.manna@xxxxxxxxx>; intel-
> gfx@xxxxxxxxxxxxxxxxxxxxx; intel-xe@xxxxxxxxxxxxxxxxxxxxx
> Cc: Hogander, Jouni <jouni.hogander@xxxxxxxxx>; B, Jeevan
> <jeevan.b@xxxxxxxxx>; Manna, Animesh <animesh.manna@xxxxxxxxx>
> Subject: Re: [PATCH v4 5/8] drm/i915/lobf: Add debug interface for lobf
>
> On Mon, 24 Feb 2025, Animesh Manna <animesh.manna@xxxxxxxxx> wrote:
> > Add an interface in debugfs which will help in debugging LOBF feature.
> >
> > v1: Initial version.
> > v2:
> > - Remove FORCE_EN flag. [Jouni]
> > - Change prefix from I915 to INTEL. [Jani]
> > - Use u8 instead of bool for lobf-debug flag. [Jani]
> >
> > Signed-off-by: Animesh Manna <animesh.manna@xxxxxxxxx>
> > ---
> > drivers/gpu/drm/i915/display/intel_alpm.c | 51 +++++++++++++++++++
> > .../drm/i915/display/intel_display_types.h | 5 ++
> > 2 files changed, 56 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_alpm.c
> > b/drivers/gpu/drm/i915/display/intel_alpm.c
> > index 83719ee1721c..5c70677ac3c0 100644
> > --- a/drivers/gpu/drm/i915/display/intel_alpm.c
> > +++ b/drivers/gpu/drm/i915/display/intel_alpm.c
> > @@ -276,6 +276,9 @@ void intel_alpm_lobf_compute_config(struct
> intel_dp *intel_dp,
> > int waketime_in_lines, first_sdp_position;
> > int context_latency, guardband;
> >
> > + if (intel_dp->alpm_parameters.lobf_debug &
> INTEL_LOBF_DEBUG_DISABLE)
> > + return;
> > +
> > if (!intel_dp_is_edp(intel_dp))
> > return;
> >
> > @@ -449,6 +452,51 @@ static int i915_edp_lobf_info_show(struct
> > seq_file *m, void *data)
> >
> > DEFINE_SHOW_ATTRIBUTE(i915_edp_lobf_info);
> >
> > +static int
> > +i915_edp_lobf_debug_get(void *data, u64 *val) {
> > + struct intel_display *display = data;
>
> Where do you pass display as data? It's connector?
I should pass display, thanks for catching.
>
> > + struct intel_encoder *encoder;
> > + int ret = -ENODEV;
> > +
> > + for_each_intel_dp(display->drm, encoder) {
> > + struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
> > +
> > + if (!intel_dp_is_edp(intel_dp))
> > + return ret;
>
> What is this supposed to do?
Other than EDP connector lobg_debug is not available, so will remove the above condition check.
>
> > +
> > + // TODO: split to each edp transcoder.
>
> What does this mean?
Currently lobf debug option only supported with one EDP, TODO added to support second EDP.
>
> > + *val = READ_ONCE(intel_dp->alpm_parameters.lobf_debug);
>
> You read this from all intel_dp and combine into one? What?
Will return from here, will take care in next version.
> > + ret = 0;
> > + }
> > +
> > + return ret;
> > +}
> > +
> > +static int
> > +i915_edp_lobf_debug_set(void *data, u64 val) {
> > + struct intel_display *display = data;
> > + struct intel_encoder *encoder;
> > + int ret = -ENODEV;
> > +
> > + for_each_intel_dp(display->drm, encoder) {
> > + struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
> > +
> > + if (!intel_dp_is_edp(intel_dp))
> > + return ret;
> > +
> > + // TODO: split to each edp transcoder.
> > + intel_dp->alpm_parameters.lobf_debug = val;
> > + }
> > +
> > + return ret;
>
> So this always returns failure?
Missed to set the ret variable, will take care in next version.
Thanks for review.
Regards,
Animesh
>
> > +}
> > +
> > +DEFINE_SIMPLE_ATTRIBUTE(i915_edp_lobf_debug_fops,
> > + i915_edp_lobf_debug_get,
> i915_edp_lobf_debug_set,
> > + "%llu\n");
> > +
> > void intel_alpm_lobf_debugfs_add(struct intel_connector *connector)
> > {
> > struct intel_display *display = to_intel_display(connector); @@
> > -458,6 +506,9 @@ void intel_alpm_lobf_debugfs_add(struct
> intel_connector *connector)
> > connector->base.connector_type !=
> DRM_MODE_CONNECTOR_eDP)
> > return;
> >
> > + debugfs_create_file("i915_edp_lobf_debug", 0644, root,
> > + connector, &i915_edp_lobf_debug_fops);
> > +
> > debugfs_create_file("i915_edp_lobf_info", 0444, root,
> > connector, &i915_edp_lobf_info_fops); } diff --git
> > a/drivers/gpu/drm/i915/display/intel_display_types.h
> > b/drivers/gpu/drm/i915/display/intel_display_types.h
> > index b78721c451b8..b6ec9a8fadd9 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> > +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> > @@ -1808,6 +1808,11 @@ struct intel_dp {
> > u8 aux_less_wake_lines;
> > u8 silence_period_sym_clocks;
> > u8 lfps_half_cycle_num_of_syms;
> > +
> > +#define INTEL_LOBF_DEBUG_MODE_MASK 0x0f
> > +#define INTEL_LOBF_DEBUG_DEFAULT 0x00
> > +#define INTEL_LOBF_DEBUG_DISABLE 0x01
> > + u8 lobf_debug;
>
> Just overly complex still.
>
> > } alpm_parameters;
> >
> > u8 alpm_dpcd;
>
> --
> Jani Nikula, Intel
