Re: [PATCH v3 6/6] drm/i915/alpm: Add debugfs for LOBF

["Hogander, Jouni" <jouni.hogander@intel.com>]

On Thu, 2024-04-25 at 00:08 +0530, Animesh Manna wrote:
> For validation purpose add debugfs for LOBF.
> 
> Signed-off-by: Animesh Manna <animesh.manna@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_alpm.c     | 48
> +++++++++++++++++++
>  drivers/gpu/drm/i915/display/intel_alpm.h     |  2 +
>  .../drm/i915/display/intel_display_debugfs.c  |  2 +
>  3 files changed, 52 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_alpm.c
> b/drivers/gpu/drm/i915/display/intel_alpm.c
> index b08799586b58..2d3027c2fb0a 100644
> --- a/drivers/gpu/drm/i915/display/intel_alpm.c
> +++ b/drivers/gpu/drm/i915/display/intel_alpm.c
> @@ -343,3 +343,51 @@ void intel_alpm_configure(struct intel_dp
> *intel_dp,
>  {
>         lnl_alpm_configure(intel_dp, crtc_state);
>  }
> +
> +static int i915_edp_lobf_info_show(struct seq_file *m, void *data)
> +{
> +       struct intel_connector *connector = m->private;
> +       struct drm_i915_private *dev_priv = to_i915(connector-
> >base.dev);
> +       struct drm_crtc *crtc;
> +       struct intel_crtc_state *crtc_state;
> +       enum transcoder cpu_transcoder;
> +       bool lobf_enabled;
> +       int ret;
> +
> +       ret = drm_modeset_lock_single_interruptible(&dev_priv-
> >drm.mode_config.connection_mutex);
> +       if (ret)
> +               return ret;
> +
> +       crtc = connector->base.state->crtc;
> +       if (connector->base.status != connector_status_connected ||
> !crtc) {
> +               ret = -ENODEV;
> +               goto out;
> +       }
> +
> +       crtc_state = to_intel_crtc_state(crtc->state);
> +       seq_printf(m, "LOBF Criteria met: %s\n",
> str_yes_no(crtc_state->has_lobf));

I'm still not convinced on this. has_lobf ~= ALPM_CTL_LOBF_ENABLE in
ALPM_CTL. To my opinion it is enough to dump seq_printf(m, "LOBF
status: %s\n", str_enabled_disabled(lobf_enabled)) below. Maybe
AUX_WAKE and AUX_LESS_WAKE could be dumped instead?

BR,

Jouni Högander

> +
> +       cpu_transcoder = crtc_state->cpu_transcoder;
> +       lobf_enabled = intel_de_read(dev_priv,
> ALPM_CTL(cpu_transcoder)) & ALPM_CTL_LOBF_ENABLE;
> +       seq_printf(m, "LOBF status: %s\n",
> str_enabled_disabled(lobf_enabled));
> +
> +out:
> +       drm_modeset_unlock(&dev_priv-
> >drm.mode_config.connection_mutex);
> +
> +       return ret;
> +}
> +
> +DEFINE_SHOW_ATTRIBUTE(i915_edp_lobf_info);
> +
> +void intel_alpm_lobf_debugfs_add(struct intel_connector *connector)
> +{
> +       struct drm_i915_private *i915 = to_i915(connector->base.dev);
> +       struct dentry *root = connector->base.debugfs_entry;
> +
> +       if (DISPLAY_VER(i915) < 20 ||
> +           connector->base.connector_type != DRM_MODE_CONNECTOR_eDP)
> +               return;
> +
> +       debugfs_create_file("i915_edp_lobf_info", 0444, root,
> +                           connector, &i915_edp_lobf_info_fops);
> +}
> diff --git a/drivers/gpu/drm/i915/display/intel_alpm.h
> b/drivers/gpu/drm/i915/display/intel_alpm.h
> index a9ca190da3e4..01fd08eb96f5 100644
> --- a/drivers/gpu/drm/i915/display/intel_alpm.h
> +++ b/drivers/gpu/drm/i915/display/intel_alpm.h
> @@ -11,6 +11,7 @@
>  struct intel_dp;
>  struct intel_crtc_state;
>  struct drm_connector_state;
> +struct intel_connector;
>  
>  bool intel_alpm_get_aux_less_status(struct intel_dp *intel_dp);
>  bool intel_alpm_compute_params(struct intel_dp *intel_dp,
> @@ -20,4 +21,5 @@ void intel_alpm_compute_lobf_config(struct intel_dp
> *intel_dp,
>                                     struct drm_connector_state
> *conn_state);
>  void intel_alpm_configure(struct intel_dp *intel_dp,
>                           const struct intel_crtc_state *crtc_state);
> +void intel_alpm_lobf_debugfs_add(struct intel_connector *connector);
>  #endif
> diff --git a/drivers/gpu/drm/i915/display/intel_display_debugfs.c
> b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
> index 35f9f86ef70f..86d9900c40af 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_debugfs.c
> +++ b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
> @@ -13,6 +13,7 @@
>  #include "i915_debugfs.h"
>  #include "i915_irq.h"
>  #include "i915_reg.h"
> +#include "intel_alpm.h"
>  #include "intel_crtc.h"
>  #include "intel_de.h"
>  #include "intel_crtc_state_dump.h"
> @@ -1515,6 +1516,7 @@ void intel_connector_debugfs_add(struct
> intel_connector *connector)
>         intel_drrs_connector_debugfs_add(connector);
>         intel_pps_connector_debugfs_add(connector);
>         intel_psr_connector_debugfs_add(connector);
> +       intel_alpm_lobf_debugfs_add(connector);
>  
>         if (connector_type == DRM_MODE_CONNECTOR_DisplayPort ||
>             connector_type == DRM_MODE_CONNECTOR_HDMIA ||