diff mbox series

[v5,27/28] drm/i915/dsc: Add Per connector debugfs node for DSC support/enable

Message ID 20181005232306.31133-28-manasi.d.navare@intel.com (mailing list archive)
State New, archived
Headers show
Series Display Stream Compression enabling on eDP/DP | expand

Commit Message

Navare, Manasi Oct. 5, 2018, 11:23 p.m. UTC
DSC can be supported per DP connector. This patch adds a per connector
debugfs node to expose DSC support capability by the kernel.
The same node can be used from userspace to force DSC enable.

Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Anusha Srivatsa <anusha.srivatsa@intel.com>
Cc: Lyude Paul <lyude@redhat.com>
Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
---
 drivers/gpu/drm/i915/i915_debugfs.c | 83 ++++++++++++++++++++++++++++-
 drivers/gpu/drm/i915/intel_dp.c     |  1 +
 drivers/gpu/drm/i915/intel_drv.h    |  3 ++
 3 files changed, 86 insertions(+), 1 deletion(-)

Comments

Lyude Paul Oct. 5, 2018, 11:34 p.m. UTC | #1
On Fri, 2018-10-05 at 16:23 -0700, Manasi Navare wrote:
> DSC can be supported per DP connector. This patch adds a per connector
> debugfs node to expose DSC support capability by the kernel.
> The same node can be used from userspace to force DSC enable.
> 
> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
> Cc: Anusha Srivatsa <anusha.srivatsa@intel.com>
> Cc: Lyude Paul <lyude@redhat.com>
> Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
> ---
>  drivers/gpu/drm/i915/i915_debugfs.c | 83 ++++++++++++++++++++++++++++-
>  drivers/gpu/drm/i915/intel_dp.c     |  1 +
>  drivers/gpu/drm/i915/intel_drv.h    |  3 ++
>  3 files changed, 86 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_debugfs.c
> b/drivers/gpu/drm/i915/i915_debugfs.c
> index f42e93b71e67..aeb20f06c79c 100644
> --- a/drivers/gpu/drm/i915/i915_debugfs.c
> +++ b/drivers/gpu/drm/i915/i915_debugfs.c
> @@ -4950,6 +4950,84 @@ static int i915_panel_show(struct seq_file *m, void
> *data)
>  }
>  DEFINE_SHOW_ATTRIBUTE(i915_panel);
>  
> +static int i915_dsc_support_show(struct seq_file *m, void *data)
> +{
> +	struct drm_connector *connector = m->private;
> +	struct intel_encoder *encoder = intel_attached_encoder(connector);
> +	struct intel_dp *intel_dp =
> +		enc_to_intel_dp(&encoder->base);
> +	struct intel_crtc *crtc;
> +	struct intel_crtc_state *crtc_state;
> +
Since we're reading from the connector status here, we should probably create
a drm_modeset_acquire_ctx and grab the connector status lock, followed by the
respective CRTC lock.

It's probably also a good idea to use an interruptible acquire ctx for this so
the user can ^C out if grabbing the lock takes too long, presumably due to
something in the kernel having hung.
> +	if (connector->status != connector_status_connected)
> +		return -ENODEV;
> +
> +	crtc = to_intel_crtc(encoder->base.crtc);
> +	crtc_state = to_intel_crtc_state(crtc->base.state);
> +	drm_modeset_lock(&crtc->base.mutex, NULL);
> +	seq_printf(m, "Enabled: %s\n",
> +		   yesno(crtc_state->dsc_params.compression_enable));
> +	seq_printf(m, "Supported: %s\n",
> +		   yesno(drm_dp_sink_supports_dsc(intel_dp->dsc_dpcd)));
> +	drm_modeset_unlock(&crtc->base.mutex);
> +
> +	return 0;
> +}
> +
> +static ssize_t i915_dsc_support_write(struct file *file,
> +				      const char __user *ubuf,
> +				      size_t len, loff_t *offp)
> +{
> +	char *input_buffer;
> +	int status = 0;
> +	bool val = false;
> +	struct drm_connector *connector =
> +		((struct seq_file *)file->private_data)->private;
> +	struct intel_encoder *encoder = intel_attached_encoder(connector);
> +	struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);

I think you forgot to lock connection_mutex here!
> +
> +	if (len == 0)
> +		return 0;
> +
> +	input_buffer = memdup_user_nul(ubuf, len);
> +	if (IS_ERR(input_buffer))
> +		return PTR_ERR(input_buffer);
> +
> +	DRM_DEBUG_DRIVER("Copied %d bytes from user to force DSC\n",
> +			 (unsigned int)len);
> +
> +	status = kstrtobool(input_buffer, &val);

You can get rid of most of this and just replace it with
kstrtobool_from_user(), which should do all of those checks for you.

> +	DRM_DEBUG_DRIVER("Got %s for DSC Enable\n",
> +			 (val) ? "true" : "false");
> +	/* To prevent erroneous enabling/disabling of DSC
> +	 * testing code, only accept an actual value of 1 or 0
> +	 */
> +	intel_dp->force_dsc_en = val;
> +
> +	kfree(input_buffer);
> +	if (status < 0)
> +		return status;
> +
> +	*offp += len;
> +	return len;
> +}
> +
> +static int i915_dsc_support_open(struct inode *inode,
> +				 struct file *file)
> +{
> +	return single_open(file, i915_dsc_support_show,
> +			   inode->i_private);
> +}
> +
> +static const struct file_operations i915_dsc_support_fops = {
> +	.owner = THIS_MODULE,
> +	.open = i915_dsc_support_open,
> +	.read = seq_read,
> +	.llseek = seq_lseek,
> +	.release = single_release,
> +	.write = i915_dsc_support_write
> +};
> +
>  /**
>   * i915_debugfs_connector_add - add i915 specific connector debugfs files
>   * @connector: pointer to a registered drm_connector
> @@ -4968,9 +5046,12 @@ int i915_debugfs_connector_add(struct drm_connector
> *connector)
>  		return -ENODEV;
>  
>  	if (connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort ||
> -	    connector->connector_type == DRM_MODE_CONNECTOR_eDP)
> +	    connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
>  		debugfs_create_file("i915_dpcd", S_IRUGO, root,
>  				    connector, &i915_dpcd_fops);
> +		debugfs_create_file("i915_dsc_support", S_IRUGO, root,
> +				    connector, &i915_dsc_support_fops);
> +	}
>  
>  	if (connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
>  		debugfs_create_file("i915_panel_timings", S_IRUGO, root,
> diff --git a/drivers/gpu/drm/i915/intel_dp.c
> b/drivers/gpu/drm/i915/intel_dp.c
> index 9a4012f3f1da..52dca5901aa1 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -2252,6 +2252,7 @@ intel_dp_compute_config(struct intel_encoder *encoder,
>  	if (adjusted_mode->flags & DRM_MODE_FLAG_DBLCLK)
>  		return false;
>  
> +	DRM_DEBUG_KMS("Force DSC en = %d\n", intel_dp->force_dsc_en);
>  	if (!intel_dp_compute_link_config(encoder, pipe_config))
>  		return false;
>  
> diff --git a/drivers/gpu/drm/i915/intel_drv.h
> b/drivers/gpu/drm/i915/intel_drv.h
> index 3996df385d33..b713b2a2d1ac 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -1163,6 +1163,9 @@ struct intel_dp {
>  
>  	/* Displayport compliance testing */
>  	struct intel_dp_compliance compliance;
> +
> +	/* Display stream compression testing */
I'd mention here that this is for debugfs as well, "Display stream compression
testing" is a bit vague
> +	bool force_dsc_en;
>  };
>  
>  struct intel_lspcon {
Navare, Manasi Oct. 9, 2018, 10:20 p.m. UTC | #2
On Fri, Oct 05, 2018 at 07:34:35PM -0400, Lyude Paul wrote:
> On Fri, 2018-10-05 at 16:23 -0700, Manasi Navare wrote:
> > DSC can be supported per DP connector. This patch adds a per connector
> > debugfs node to expose DSC support capability by the kernel.
> > The same node can be used from userspace to force DSC enable.
> > 
> > Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> > Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
> > Cc: Anusha Srivatsa <anusha.srivatsa@intel.com>
> > Cc: Lyude Paul <lyude@redhat.com>
> > Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
> > ---
> >  drivers/gpu/drm/i915/i915_debugfs.c | 83 ++++++++++++++++++++++++++++-
> >  drivers/gpu/drm/i915/intel_dp.c     |  1 +
> >  drivers/gpu/drm/i915/intel_drv.h    |  3 ++
> >  3 files changed, 86 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/i915_debugfs.c
> > b/drivers/gpu/drm/i915/i915_debugfs.c
> > index f42e93b71e67..aeb20f06c79c 100644
> > --- a/drivers/gpu/drm/i915/i915_debugfs.c
> > +++ b/drivers/gpu/drm/i915/i915_debugfs.c
> > @@ -4950,6 +4950,84 @@ static int i915_panel_show(struct seq_file *m, void
> > *data)
> >  }
> >  DEFINE_SHOW_ATTRIBUTE(i915_panel);
> >  
> > +static int i915_dsc_support_show(struct seq_file *m, void *data)
> > +{
> > +	struct drm_connector *connector = m->private;
> > +	struct intel_encoder *encoder = intel_attached_encoder(connector);
> > +	struct intel_dp *intel_dp =
> > +		enc_to_intel_dp(&encoder->base);
> > +	struct intel_crtc *crtc;
> > +	struct intel_crtc_state *crtc_state;
> > +
> Since we're reading from the connector status here, we should probably create
> a drm_modeset_acquire_ctx and grab the connector status lock, followed by the
> respective CRTC lock.
>

I see that none of the other nodes for Eg: i915_panel_show or i915_dpcd_show grab
connector_status lock for reading the connector->status

And before reading the crtc_state info,I am grabbing a drm_modeset_lock(&crtc->base.mutex, NULL);
Doesn't this suffice?
 
> It's probably also a good idea to use an interruptible acquire ctx for this so
> the user can ^C out if grabbing the lock takes too long, presumably due to
> something in the kernel having hung.
> > +	if (connector->status != connector_status_connected)
> > +		return -ENODEV;
> > +
> > +	crtc = to_intel_crtc(encoder->base.crtc);
> > +	crtc_state = to_intel_crtc_state(crtc->base.state);
> > +	drm_modeset_lock(&crtc->base.mutex, NULL);
> > +	seq_printf(m, "Enabled: %s\n",
> > +		   yesno(crtc_state->dsc_params.compression_enable));
> > +	seq_printf(m, "Supported: %s\n",
> > +		   yesno(drm_dp_sink_supports_dsc(intel_dp->dsc_dpcd)));
> > +	drm_modeset_unlock(&crtc->base.mutex);
> > +
> > +	return 0;
> > +}
> > +
> > +static ssize_t i915_dsc_support_write(struct file *file,
> > +				      const char __user *ubuf,
> > +				      size_t len, loff_t *offp)
> > +{
> > +	char *input_buffer;
> > +	int status = 0;
> > +	bool val = false;
> > +	struct drm_connector *connector =
> > +		((struct seq_file *)file->private_data)->private;
> > +	struct intel_encoder *encoder = intel_attached_encoder(connector);
> > +	struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);
> 
> I think you forgot to lock connection_mutex here!

But here I am not reading any crtc_state variable or writing to crtc_state
Do I still need connection_mutex?

> > +
> > +	if (len == 0)
> > +		return 0;
> > +
> > +	input_buffer = memdup_user_nul(ubuf, len);
> > +	if (IS_ERR(input_buffer))
> > +		return PTR_ERR(input_buffer);
> > +
> > +	DRM_DEBUG_DRIVER("Copied %d bytes from user to force DSC\n",
> > +			 (unsigned int)len);
> > +
> > +	status = kstrtobool(input_buffer, &val);
> 
> You can get rid of most of this and just replace it with
> kstrtobool_from_user(), which should do all of those checks for you.
>

Agreed, will use kstrtobool_from_user and avoid all the error checking manually

Manasi
 
> > +	DRM_DEBUG_DRIVER("Got %s for DSC Enable\n",
> > +			 (val) ? "true" : "false");
> > +	/* To prevent erroneous enabling/disabling of DSC
> > +	 * testing code, only accept an actual value of 1 or 0
> > +	 */
> > +	intel_dp->force_dsc_en = val;
> > +
> > +	kfree(input_buffer);
> > +	if (status < 0)
> > +		return status;
> > +
> > +	*offp += len;
> > +	return len;
> > +}
> > +
> > +static int i915_dsc_support_open(struct inode *inode,
> > +				 struct file *file)
> > +{
> > +	return single_open(file, i915_dsc_support_show,
> > +			   inode->i_private);
> > +}
> > +
> > +static const struct file_operations i915_dsc_support_fops = {
> > +	.owner = THIS_MODULE,
> > +	.open = i915_dsc_support_open,
> > +	.read = seq_read,
> > +	.llseek = seq_lseek,
> > +	.release = single_release,
> > +	.write = i915_dsc_support_write
> > +};
> > +
> >  /**
> >   * i915_debugfs_connector_add - add i915 specific connector debugfs files
> >   * @connector: pointer to a registered drm_connector
> > @@ -4968,9 +5046,12 @@ int i915_debugfs_connector_add(struct drm_connector
> > *connector)
> >  		return -ENODEV;
> >  
> >  	if (connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort ||
> > -	    connector->connector_type == DRM_MODE_CONNECTOR_eDP)
> > +	    connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
> >  		debugfs_create_file("i915_dpcd", S_IRUGO, root,
> >  				    connector, &i915_dpcd_fops);
> > +		debugfs_create_file("i915_dsc_support", S_IRUGO, root,
> > +				    connector, &i915_dsc_support_fops);
> > +	}
> >  
> >  	if (connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
> >  		debugfs_create_file("i915_panel_timings", S_IRUGO, root,
> > diff --git a/drivers/gpu/drm/i915/intel_dp.c
> > b/drivers/gpu/drm/i915/intel_dp.c
> > index 9a4012f3f1da..52dca5901aa1 100644
> > --- a/drivers/gpu/drm/i915/intel_dp.c
> > +++ b/drivers/gpu/drm/i915/intel_dp.c
> > @@ -2252,6 +2252,7 @@ intel_dp_compute_config(struct intel_encoder *encoder,
> >  	if (adjusted_mode->flags & DRM_MODE_FLAG_DBLCLK)
> >  		return false;
> >  
> > +	DRM_DEBUG_KMS("Force DSC en = %d\n", intel_dp->force_dsc_en);
> >  	if (!intel_dp_compute_link_config(encoder, pipe_config))
> >  		return false;
> >  
> > diff --git a/drivers/gpu/drm/i915/intel_drv.h
> > b/drivers/gpu/drm/i915/intel_drv.h
> > index 3996df385d33..b713b2a2d1ac 100644
> > --- a/drivers/gpu/drm/i915/intel_drv.h
> > +++ b/drivers/gpu/drm/i915/intel_drv.h
> > @@ -1163,6 +1163,9 @@ struct intel_dp {
> >  
> >  	/* Displayport compliance testing */
> >  	struct intel_dp_compliance compliance;
> > +
> > +	/* Display stream compression testing */
> I'd mention here that this is for debugfs as well, "Display stream compression
> testing" is a bit vague
> > +	bool force_dsc_en;
> >  };
> >  
> >  struct intel_lspcon {
> -- 
> Cheers,
> 	Lyude Paul
>
Lyude Paul Oct. 9, 2018, 10:24 p.m. UTC | #3
On Tue, 2018-10-09 at 15:20 -0700, Manasi Navare wrote:
> On Fri, Oct 05, 2018 at 07:34:35PM -0400, Lyude Paul wrote:
> > On Fri, 2018-10-05 at 16:23 -0700, Manasi Navare wrote:
> > > DSC can be supported per DP connector. This patch adds a per connector
> > > debugfs node to expose DSC support capability by the kernel.
> > > The same node can be used from userspace to force DSC enable.
> > > 
> > > Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> > > Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
> > > Cc: Anusha Srivatsa <anusha.srivatsa@intel.com>
> > > Cc: Lyude Paul <lyude@redhat.com>
> > > Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
> > > ---
> > >  drivers/gpu/drm/i915/i915_debugfs.c | 83 ++++++++++++++++++++++++++++-
> > >  drivers/gpu/drm/i915/intel_dp.c     |  1 +
> > >  drivers/gpu/drm/i915/intel_drv.h    |  3 ++
> > >  3 files changed, 86 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/gpu/drm/i915/i915_debugfs.c
> > > b/drivers/gpu/drm/i915/i915_debugfs.c
> > > index f42e93b71e67..aeb20f06c79c 100644
> > > --- a/drivers/gpu/drm/i915/i915_debugfs.c
> > > +++ b/drivers/gpu/drm/i915/i915_debugfs.c
> > > @@ -4950,6 +4950,84 @@ static int i915_panel_show(struct seq_file *m,
> > > void
> > > *data)
> > >  }
> > >  DEFINE_SHOW_ATTRIBUTE(i915_panel);
> > >  
> > > +static int i915_dsc_support_show(struct seq_file *m, void *data)
> > > +{
> > > +	struct drm_connector *connector = m->private;
> > > +	struct intel_encoder *encoder = intel_attached_encoder(connector);
> > > +	struct intel_dp *intel_dp =
> > > +		enc_to_intel_dp(&encoder->base);
> > > +	struct intel_crtc *crtc;
> > > +	struct intel_crtc_state *crtc_state;
> > > +
> > 
> > Since we're reading from the connector status here, we should probably
> > create
> > a drm_modeset_acquire_ctx and grab the connector status lock, followed by
> > the
> > respective CRTC lock.
> > 
> 
> I see that none of the other nodes for Eg: i915_panel_show or i915_dpcd_show
> grab
> connector_status lock for reading the connector->status
Huh, I guess I must have missed that 
> 
> And before reading the crtc_state info,I am grabbing a
> drm_modeset_lock(&crtc->base.mutex, NULL);
> Doesn't this suffice?

Mhm, normally it wouldn't but I suppose since we're only reading a single
member from connector-> and not modifying any parts of it in response then I
think you're right, you should be fine without grabbing that lock. Sorry
about that!


>  
> > It's probably also a good idea to use an interruptible acquire ctx for
> > this so
> > the user can ^C out if grabbing the lock takes too long, presumably due to
> > something in the kernel having hung.
> > > +	if (connector->status != connector_status_connected)
> > > +		return -ENODEV;
> > > +
> > > +	crtc = to_intel_crtc(encoder->base.crtc);
> > > +	crtc_state = to_intel_crtc_state(crtc->base.state);
> > > +	drm_modeset_lock(&crtc->base.mutex, NULL);
> > > +	seq_printf(m, "Enabled: %s\n",
> > > +		   yesno(crtc_state->dsc_params.compression_enable));
> > > +	seq_printf(m, "Supported: %s\n",
> > > +		   yesno(drm_dp_sink_supports_dsc(intel_dp->dsc_dpcd)));
> > > +	drm_modeset_unlock(&crtc->base.mutex);
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static ssize_t i915_dsc_support_write(struct file *file,
> > > +				      const char __user *ubuf,
> > > +				      size_t len, loff_t *offp)
> > > +{
> > > +	char *input_buffer;
> > > +	int status = 0;
> > > +	bool val = false;
> > > +	struct drm_connector *connector =
> > > +		((struct seq_file *)file->private_data)->private;
> > > +	struct intel_encoder *encoder = intel_attached_encoder(connector);
> > > +	struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);
> > 
> > I think you forgot to lock connection_mutex here!
> 
> But here I am not reading any crtc_state variable or writing to crtc_state
> Do I still need connection_mutex?
> 
> > > +
> > > +	if (len == 0)
> > > +		return 0;
> > > +
> > > +	input_buffer = memdup_user_nul(ubuf, len);
> > > +	if (IS_ERR(input_buffer))
> > > +		return PTR_ERR(input_buffer);
> > > +
> > > +	DRM_DEBUG_DRIVER("Copied %d bytes from user to force DSC\n",
> > > +			 (unsigned int)len);
> > > +
> > > +	status = kstrtobool(input_buffer, &val);
> > 
> > You can get rid of most of this and just replace it with
> > kstrtobool_from_user(), which should do all of those checks for you.
> > 
> 
> Agreed, will use kstrtobool_from_user and avoid all the error checking
> manually
> 
> Manasi
>  
> > > +	DRM_DEBUG_DRIVER("Got %s for DSC Enable\n",
> > > +			 (val) ? "true" : "false");
> > > +	/* To prevent erroneous enabling/disabling of DSC
> > > +	 * testing code, only accept an actual value of 1 or 0
> > > +	 */
> > > +	intel_dp->force_dsc_en = val;
> > > +
> > > +	kfree(input_buffer);
> > > +	if (status < 0)
> > > +		return status;
> > > +
> > > +	*offp += len;
> > > +	return len;
> > > +}
> > > +
> > > +static int i915_dsc_support_open(struct inode *inode,
> > > +				 struct file *file)
> > > +{
> > > +	return single_open(file, i915_dsc_support_show,
> > > +			   inode->i_private);
> > > +}
> > > +
> > > +static const struct file_operations i915_dsc_support_fops = {
> > > +	.owner = THIS_MODULE,
> > > +	.open = i915_dsc_support_open,
> > > +	.read = seq_read,
> > > +	.llseek = seq_lseek,
> > > +	.release = single_release,
> > > +	.write = i915_dsc_support_write
> > > +};
> > > +
> > >  /**
> > >   * i915_debugfs_connector_add - add i915 specific connector debugfs
> > > files
> > >   * @connector: pointer to a registered drm_connector
> > > @@ -4968,9 +5046,12 @@ int i915_debugfs_connector_add(struct
> > > drm_connector
> > > *connector)
> > >  		return -ENODEV;
> > >  
> > >  	if (connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort ||
> > > -	    connector->connector_type == DRM_MODE_CONNECTOR_eDP)
> > > +	    connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
> > >  		debugfs_create_file("i915_dpcd", S_IRUGO, root,
> > >  				    connector, &i915_dpcd_fops);
> > > +		debugfs_create_file("i915_dsc_support", S_IRUGO, root,
> > > +				    connector, &i915_dsc_support_fops);
> > > +	}
> > >  
> > >  	if (connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
> > >  		debugfs_create_file("i915_panel_timings", S_IRUGO, root,
> > > diff --git a/drivers/gpu/drm/i915/intel_dp.c
> > > b/drivers/gpu/drm/i915/intel_dp.c
> > > index 9a4012f3f1da..52dca5901aa1 100644
> > > --- a/drivers/gpu/drm/i915/intel_dp.c
> > > +++ b/drivers/gpu/drm/i915/intel_dp.c
> > > @@ -2252,6 +2252,7 @@ intel_dp_compute_config(struct intel_encoder
> > > *encoder,
> > >  	if (adjusted_mode->flags & DRM_MODE_FLAG_DBLCLK)
> > >  		return false;
> > >  
> > > +	DRM_DEBUG_KMS("Force DSC en = %d\n", intel_dp->force_dsc_en);
> > >  	if (!intel_dp_compute_link_config(encoder, pipe_config))
> > >  		return false;
> > >  
> > > diff --git a/drivers/gpu/drm/i915/intel_drv.h
> > > b/drivers/gpu/drm/i915/intel_drv.h
> > > index 3996df385d33..b713b2a2d1ac 100644
> > > --- a/drivers/gpu/drm/i915/intel_drv.h
> > > +++ b/drivers/gpu/drm/i915/intel_drv.h
> > > @@ -1163,6 +1163,9 @@ struct intel_dp {
> > >  
> > >  	/* Displayport compliance testing */
> > >  	struct intel_dp_compliance compliance;
> > > +
> > > +	/* Display stream compression testing */
> > 
> > I'd mention here that this is for debugfs as well, "Display stream
> > compression
> > testing" is a bit vague
> > > +	bool force_dsc_en;
> > >  };
> > >  
> > >  struct intel_lspcon {
> > 
> > -- 
> > Cheers,
> > 	Lyude Paul
> >
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index f42e93b71e67..aeb20f06c79c 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -4950,6 +4950,84 @@  static int i915_panel_show(struct seq_file *m, void *data)
 }
 DEFINE_SHOW_ATTRIBUTE(i915_panel);
 
+static int i915_dsc_support_show(struct seq_file *m, void *data)
+{
+	struct drm_connector *connector = m->private;
+	struct intel_encoder *encoder = intel_attached_encoder(connector);
+	struct intel_dp *intel_dp =
+		enc_to_intel_dp(&encoder->base);
+	struct intel_crtc *crtc;
+	struct intel_crtc_state *crtc_state;
+
+	if (connector->status != connector_status_connected)
+		return -ENODEV;
+
+	crtc = to_intel_crtc(encoder->base.crtc);
+	crtc_state = to_intel_crtc_state(crtc->base.state);
+	drm_modeset_lock(&crtc->base.mutex, NULL);
+	seq_printf(m, "Enabled: %s\n",
+		   yesno(crtc_state->dsc_params.compression_enable));
+	seq_printf(m, "Supported: %s\n",
+		   yesno(drm_dp_sink_supports_dsc(intel_dp->dsc_dpcd)));
+	drm_modeset_unlock(&crtc->base.mutex);
+
+	return 0;
+}
+
+static ssize_t i915_dsc_support_write(struct file *file,
+				      const char __user *ubuf,
+				      size_t len, loff_t *offp)
+{
+	char *input_buffer;
+	int status = 0;
+	bool val = false;
+	struct drm_connector *connector =
+		((struct seq_file *)file->private_data)->private;
+	struct intel_encoder *encoder = intel_attached_encoder(connector);
+	struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);
+
+	if (len == 0)
+		return 0;
+
+	input_buffer = memdup_user_nul(ubuf, len);
+	if (IS_ERR(input_buffer))
+		return PTR_ERR(input_buffer);
+
+	DRM_DEBUG_DRIVER("Copied %d bytes from user to force DSC\n",
+			 (unsigned int)len);
+
+	status = kstrtobool(input_buffer, &val);
+	DRM_DEBUG_DRIVER("Got %s for DSC Enable\n",
+			 (val) ? "true" : "false");
+	/* To prevent erroneous enabling/disabling of DSC
+	 * testing code, only accept an actual value of 1 or 0
+	 */
+	intel_dp->force_dsc_en = val;
+
+	kfree(input_buffer);
+	if (status < 0)
+		return status;
+
+	*offp += len;
+	return len;
+}
+
+static int i915_dsc_support_open(struct inode *inode,
+				 struct file *file)
+{
+	return single_open(file, i915_dsc_support_show,
+			   inode->i_private);
+}
+
+static const struct file_operations i915_dsc_support_fops = {
+	.owner = THIS_MODULE,
+	.open = i915_dsc_support_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = single_release,
+	.write = i915_dsc_support_write
+};
+
 /**
  * i915_debugfs_connector_add - add i915 specific connector debugfs files
  * @connector: pointer to a registered drm_connector
@@ -4968,9 +5046,12 @@  int i915_debugfs_connector_add(struct drm_connector *connector)
 		return -ENODEV;
 
 	if (connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort ||
-	    connector->connector_type == DRM_MODE_CONNECTOR_eDP)
+	    connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
 		debugfs_create_file("i915_dpcd", S_IRUGO, root,
 				    connector, &i915_dpcd_fops);
+		debugfs_create_file("i915_dsc_support", S_IRUGO, root,
+				    connector, &i915_dsc_support_fops);
+	}
 
 	if (connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
 		debugfs_create_file("i915_panel_timings", S_IRUGO, root,
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 9a4012f3f1da..52dca5901aa1 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -2252,6 +2252,7 @@  intel_dp_compute_config(struct intel_encoder *encoder,
 	if (adjusted_mode->flags & DRM_MODE_FLAG_DBLCLK)
 		return false;
 
+	DRM_DEBUG_KMS("Force DSC en = %d\n", intel_dp->force_dsc_en);
 	if (!intel_dp_compute_link_config(encoder, pipe_config))
 		return false;
 
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 3996df385d33..b713b2a2d1ac 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1163,6 +1163,9 @@  struct intel_dp {
 
 	/* Displayport compliance testing */
 	struct intel_dp_compliance compliance;
+
+	/* Display stream compression testing */
+	bool force_dsc_en;
 };
 
 struct intel_lspcon {