On Wed, 08 Jan 2025, "Hogander, Jouni" <jouni.hogander@xxxxxxxxx> wrote:
> On Mon, 2025-01-06 at 09:45 +0530, Animesh Manna wrote:
>> Add an interface in debugfs which will help in debugging LOBF
>> feature.
>>
>> Signed-off-by: Animesh Manna <animesh.manna@xxxxxxxxx>
>> ---
>> drivers/gpu/drm/i915/display/intel_alpm.c | 51
>> +++++++++++++++++++
>> .../drm/i915/display/intel_display_types.h | 6 +++
>> 2 files changed, 57 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/i915/display/intel_alpm.c
>> b/drivers/gpu/drm/i915/display/intel_alpm.c
>> index 197c67363f0e..1cc0e5ed3f74 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 &
>> I915_LOBF_DEBUG_DISABLE)
>> + return;
>> +
>> if (!intel_dp_is_edp(intel_dp))
>> return;
>>
>> @@ -448,6 +451,51 @@ 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;
>> + 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.
>> + *val = READ_ONCE(intel_dp-
>> >alpm_parameters.lobf_debug);
>> + 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;
>> +}
>> +
>> +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);
>> @@ -457,6 +505,9 @@ 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 f230163226d1..37f061acb204 100644
>> --- a/drivers/gpu/drm/i915/display/intel_display_types.h
>> +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
>> @@ -1800,6 +1800,12 @@ struct intel_dp {
>> u8 aux_less_wake_lines;
>> u8 silence_period_sym_clocks;
>> u8 lfps_half_cycle_num_of_syms;
>> +
>> +#define I915_LOBF_DEBUG_MODE_MASK 0x0f
>> +#define I915_LOBF_DEBUG_DEFAULT 0x00
>> +#define I915_LOBF_DEBUG_DISABLE 0x01
>> +#define I915_LOBF_DEBUG_FORCE_EN 0x02
>
> FORCE_EN is not needed. You can achieve LOBF (if it's possible) by
> disabling PSR/PR.
To be honest, I don't like adding these debug mode masks at all. Don't
make it so complicated. Moreover, the only user of any of these is
intel_dp->alpm_parameters.lobf_debug & I915_LOBF_DEBUG_DISABLE
but lobf_debug is *boolean*!
Keep it simple.
And "i915" naming in display code is discouraged, unless it's in
reference to i915 as the platform.
BR,
Jani.
>
> BR,
>
> Jouni Högander
>
>> + bool lobf_debug;
>> } alpm_parameters;
>>
>> u8 alpm_dpcd;
>
--
Jani Nikula, Intel
