Re: [Intel-gfx] [PATCH 50/53] drm/i915/display/dsc: Add Per connector debugfs node for DSC BPP enable

["Kulkarni, Vandita" <vandita.kulkarni@intel.com>]

Now, this change and changes from patch 51 of this series is taken care as part of the below series
https://patchwork.freedesktop.org/series/92750/
and merged.

Thanks,
Vandita
> -----Original Message-----
> From: Jani Nikula <jani.nikula@linux.intel.com>
> Sent: Friday, July 2, 2021 1:50 PM
> To: Roper, Matthew D <matthew.d.roper@intel.com>; intel-
> gfx@lists.freedesktop.org
> Cc: Patnana, Venkata Sai <venkata.sai.patnana@intel.com>; Srivatsa, Anusha
> <anusha.srivatsa@intel.com>; dri-devel@lists.freedesktop.org; Navare,
> Manasi D <manasi.d.navare@intel.com>; Kulkarni, Vandita
> <vandita.kulkarni@intel.com>
> Subject: Re: [PATCH 50/53] drm/i915/display/dsc: Add Per connector debugfs
> node for DSC BPP enable
> 
> On Thu, 01 Jul 2021, Matt Roper <matthew.d.roper@intel.com> wrote:
> > From: Anusha Srivatsa <anusha.srivatsa@intel.com>
> >
> > DSC can be supported per DP connector. This patch creates a per
> > connector debugfs node to expose the Input and Compressed BPP.
> >
> > The same node can be used from userspace to force DSC to a certain
> > BPP.
> >
> > force_dsc_bpp is written through this debugfs node to force DSC BPP to
> > all accepted values
> 
> I think this patch needs rework, and it's independent of the rest of the
> series. Please just drop this one and the next.
> 
> BR,
> Jani.
> 
> >
> > Cc: Vandita Kulkarni <vandita.kulkarni@intel.com>
> > Cc: Manasi Navare <manasi.d.navare@intel.com>
> > Signed-off-by: Anusha Srivatsa <anusha.srivatsa@intel.com>
> > Signed-off-by: Patnana Venkata Sai <venkata.sai.patnana@intel.com>
> > Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
> > ---
> >  .../drm/i915/display/intel_display_debugfs.c  | 103 +++++++++++++++++-
> >  .../drm/i915/display/intel_display_types.h    |   1 +
> >  2 files changed, 103 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_display_debugfs.c
> > b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
> > index af9e58619667..1805d70ea817 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display_debugfs.c
> > +++ b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
> > @@ -2389,6 +2389,100 @@ static const struct file_operations
> i915_dsc_fec_support_fops = {
> >  	.write = i915_dsc_fec_support_write
> >  };
> >
> > +static int i915_dsc_bpp_support_show(struct seq_file *m, void *data)
> > +{
> > +	struct drm_connector *connector = m->private;
> > +	struct drm_device *dev = connector->dev;
> > +	struct drm_crtc *crtc;
> > +	struct intel_dp *intel_dp;
> > +	struct drm_modeset_acquire_ctx ctx;
> > +	struct intel_crtc_state *crtc_state = NULL;
> > +	int ret = 0;
> > +	bool try_again = false;
> > +
> > +	drm_modeset_acquire_init(&ctx,
> DRM_MODESET_ACQUIRE_INTERRUPTIBLE);
> > +
> > +	do {
> > +		try_again = false;
> > +		ret = drm_modeset_lock(&dev-
> >mode_config.connection_mutex,
> > +				       &ctx);
> > +		if (ret) {
> > +			ret = -EINTR;
> > +			break;
> > +		}
> > +		crtc = connector->state->crtc;
> > +		if (connector->status != connector_status_connected ||
> !crtc) {
> > +			ret = -ENODEV;
> > +			break;
> > +		}
> > +		ret = drm_modeset_lock(&crtc->mutex, &ctx);
> > +		if (ret == -EDEADLK) {
> > +			ret = drm_modeset_backoff(&ctx);
> > +			if (!ret) {
> > +				try_again = true;
> > +				continue;
> > +			}
> > +			break;
> > +		} else if (ret) {
> > +			break;
> > +		}
> > +		intel_dp =
> intel_attached_dp(to_intel_connector(connector));
> > +		crtc_state = to_intel_crtc_state(crtc->state);
> > +		seq_printf(m, "Input_BPP: %d\n", crtc_state->pipe_bpp);
> > +		seq_printf(m, "Compressed_BPP: %d\n",
> > +				crtc_state->dsc.compressed_bpp);
> > +	} while (try_again);
> > +
> > +	drm_modeset_drop_locks(&ctx);
> > +	drm_modeset_acquire_fini(&ctx);
> > +
> > +	return ret;
> > +}
> > +
> > +static ssize_t i915_dsc_bpp_support_write(struct file *file,
> > +						const char __user *ubuf,
> > +						size_t len, loff_t *offp)
> > +{
> > +	int dsc_bpp = 0;
> > +	int ret;
> > +	struct drm_connector *connector =
> > +		((struct seq_file *)file->private_data)->private;
> > +	struct intel_encoder *encoder =
> intel_attached_encoder(to_intel_connector(connector));
> > +	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
> > +	struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
> > +
> > +	if (len == 0)
> > +		return 0;
> > +
> > +	drm_dbg(&i915->drm,
> > +		"Copied %zu bytes from user to force BPP\n", len);
> > +
> > +	ret = kstrtoint_from_user(ubuf, len, 0, &dsc_bpp);
> > +
> > +	intel_dp->force_dsc_bpp = dsc_bpp;
> > +	if (ret < 0)
> > +		return ret;
> > +
> > +	*offp += len;
> > +	return len;
> > +}
> > +
> > +static int i915_dsc_bpp_support_open(struct inode *inode,
> > +					   struct file *file)
> > +{
> > +	return single_open(file, i915_dsc_bpp_support_show,
> > +			   inode->i_private);
> > +}
> > +
> > +static const struct file_operations i915_dsc_bpp_support_fops = {
> > +	.owner = THIS_MODULE,
> > +	.open = i915_dsc_bpp_support_open,
> > +	.read = seq_read,
> > +	.llseek = seq_lseek,
> > +	.release = single_release,
> > +	.write = i915_dsc_bpp_support_write
> > +};
> > +
> >  /**
> >   * intel_connector_debugfs_add - add i915 specific connector debugfs files
> >   * @connector: pointer to a registered drm_connector @@ -2427,9
> > +2521,16 @@ int intel_connector_debugfs_add(struct drm_connector
> *connector)
> >  				    connector,
> &i915_hdcp_sink_capability_fops);
> >  	}
> >
> > -	if ((DISPLAY_VER(dev_priv) >= 11 || IS_CANNONLAKE(dev_priv)) &&
> ((connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort &&
> !to_intel_connector(connector)->mst_port) || connector->connector_type
> == DRM_MODE_CONNECTOR_eDP))
> > +	if ((DISPLAY_VER(dev_priv) >= 11 || IS_CANNONLAKE(dev_priv)) &&
> > +	    ((connector->connector_type ==
> DRM_MODE_CONNECTOR_DisplayPort &&
> > +	      !to_intel_connector(connector)->mst_port) ||
> > +	     connector->connector_type == DRM_MODE_CONNECTOR_eDP))
> {
> >  		debugfs_create_file("i915_dsc_fec_support", S_IRUGO,
> root,
> >  				    connector, &i915_dsc_fec_support_fops);
> > +		debugfs_create_file("i915_dsc_bpp_support", 0444,
> > +				    root, connector,
> > +				    &i915_dsc_bpp_support_fops);
> > +	}
> >
> >  	/* Legacy panels doesn't lpsp on any platform */
> >  	if ((DISPLAY_VER(dev_priv) >= 9 || IS_HASWELL(dev_priv) || diff
> > --git a/drivers/gpu/drm/i915/display/intel_display_types.h
> > b/drivers/gpu/drm/i915/display/intel_display_types.h
> > index 29ae1d9b5abc..00320d89d266 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> > +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> > @@ -1627,6 +1627,7 @@ struct intel_dp {
> >
> >  	/* Display stream compression testing */
> >  	bool force_dsc_en;
> > +	int force_dsc_bpp;
> >
> >  	bool hobl_failed;
> >  	bool hobl_active;
> 
> --
> Jani Nikula, Intel Open Source Graphics Center