| Message ID | 20181204195537.5274-1-manasi.d.navare@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v6] drm/i915/dsc: Add Per connector debugfs node for DSC support/enable | expand |
Looks good, some small nitpicks On Tue, 2018-12-04 at 11:55 -0800, 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. > > force_dsc_en written through this debugfs node is used to force > DSC even for lower resolutions. > > v6: > * Read fec_capable only for non edp (Manasi) > v5: > * Name it dsc sink support and also add > fec support in the same node (Ville) > v4: > * Add missed connector_status check (Manasi) > * Create i915_dsc_support node only for Gen >=10 (manasi) > * Access intel_dp->dsc_dpcd only if its not NULL (Manasi) > v3: > * Combine Force_dsc_en with this patch (Ville) > v2: > * Use kstrtobool_from_user to avoid explicit error checking (Lyude) > * Rebase on drm-tip (Manasi) > > 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 | 80 +++++++++++++++++++++++++++++ > drivers/gpu/drm/i915/intel_dp.c | 3 +- > drivers/gpu/drm/i915/intel_drv.h | 3 ++ > 3 files changed, 85 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/i915_debugfs.c > b/drivers/gpu/drm/i915/i915_debugfs.c > index 129b9a6f8309..ec10ab027d18 100644 > --- a/drivers/gpu/drm/i915/i915_debugfs.c > +++ b/drivers/gpu/drm/i915/i915_debugfs.c > @@ -5086,6 +5086,79 @@ static int i915_hdcp_sink_capability_show(struct > seq_file *m, void *data) > } > DEFINE_SHOW_ATTRIBUTE(i915_hdcp_sink_capability); > > +static int i915_dsc_fec_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, "DSC_Enabled: %s\n", > + yesno(crtc_state->dsc_params.compression_enable)); > + if (intel_dp->dsc_dpcd) > + seq_printf(m, "DSC_Sink_Support: %s\n", > + yesno(drm_dp_sink_supports_dsc(intel_dp- > >dsc_dpcd))); > + if (!intel_dp_is_edp(intel_dp)) > + seq_printf(m, "FEC_Sink_Support: %s\n", > + yesno(drm_dp_sink_supports_fec(intel_dp- > >fec_capable))); > + drm_modeset_unlock(&crtc->base.mutex); > + > + return 0; > +} > + > +static ssize_t i915_dsc_fec_support_write(struct file *file, > + const char __user *ubuf, > + size_t len, loff_t *offp) > +{ > + bool dsc_enable = false; > + int ret; > + 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; > + > + DRM_DEBUG_DRIVER("Copied %d bytes from user to force DSC\n", > + (unsigned int)len); You can just use %zu instead of %d here, see: https://01.org/linuxgraphics/gfx-docs/drm/core-api/printk-formats.html Other then that, looks good to me! With that change: Reviewed-by: Lyude Paul <lyude@redhat.com> > + > + ret = kstrtobool_from_user(ubuf, len, &dsc_enable); > + if (ret < 0) > + return ret; > + > + DRM_DEBUG_DRIVER("Got %s for DSC Enable\n", > + (dsc_enable) ? "true" : "false"); > + intel_dp->force_dsc_en = dsc_enable; > + > + *offp += len; > + return len; > +} > + > +static int i915_dsc_fec_support_open(struct inode *inode, > + struct file *file) > +{ > + return single_open(file, i915_dsc_fec_support_show, > + inode->i_private); > +} > + > +static const struct file_operations i915_dsc_fec_support_fops = { > + .owner = THIS_MODULE, > + .open = i915_dsc_fec_support_open, > + .read = seq_read, > + .llseek = seq_lseek, > + .release = single_release, > + .write = i915_dsc_fec_support_write > +}; > + > /** > * i915_debugfs_connector_add - add i915 specific connector debugfs files > * @connector: pointer to a registered drm_connector > @@ -5098,6 +5171,7 @@ DEFINE_SHOW_ATTRIBUTE(i915_hdcp_sink_capability); > int i915_debugfs_connector_add(struct drm_connector *connector) > { > struct dentry *root = connector->debugfs_entry; > + struct drm_i915_private *dev_priv = to_i915(connector->dev); > > /* The connector must have been registered beforehands. */ > if (!root) > @@ -5122,5 +5196,11 @@ int i915_debugfs_connector_add(struct drm_connector > *connector) > connector, > &i915_hdcp_sink_capability_fops); > } > > + if (INTEL_GEN(dev_priv) >= 10 && > + (connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort || > + connector->connector_type == DRM_MODE_CONNECTOR_eDP)) > + debugfs_create_file("i915_dsc_fec_support", S_IRUGO, root, > + connector, &i915_dsc_fec_support_fops); > + > return 0; > } > diff --git a/drivers/gpu/drm/i915/intel_dp.c > b/drivers/gpu/drm/i915/intel_dp.c > index a6907a1761ab..2e3097cae277 100644 > --- a/drivers/gpu/drm/i915/intel_dp.c > +++ b/drivers/gpu/drm/i915/intel_dp.c > @@ -2051,7 +2051,8 @@ intel_dp_compute_link_config(struct intel_encoder > *encoder, > &limits); > > /* enable compression if the mode doesn't fit available BW */ > - if (!ret) { > + DRM_DEBUG_KMS("Force DSC en = %d\n", intel_dp->force_dsc_en); > + if (!ret || intel_dp->force_dsc_en) { > if (!intel_dp_dsc_compute_config(intel_dp, pipe_config, > conn_state, &limits)) > return false; > diff --git a/drivers/gpu/drm/i915/intel_drv.h > b/drivers/gpu/drm/i915/intel_drv.h > index f94a04b4ad87..0cedce438433 100644 > --- a/drivers/gpu/drm/i915/intel_drv.h > +++ b/drivers/gpu/drm/i915/intel_drv.h > @@ -1209,6 +1209,9 @@ struct intel_dp { > > /* Displayport compliance testing */ > struct intel_dp_compliance compliance; > + > + /* Display stream compression testing */ > + bool force_dsc_en; > }; > > enum lspcon_vendor {
On Wed, Dec 05, 2018 at 02:00:39PM -0500, Lyude Paul wrote: > Looks good, some small nitpicks > > On Tue, 2018-12-04 at 11:55 -0800, 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. > > > > force_dsc_en written through this debugfs node is used to force > > DSC even for lower resolutions. > > > > v6: > > * Read fec_capable only for non edp (Manasi) > > v5: > > * Name it dsc sink support and also add > > fec support in the same node (Ville) > > v4: > > * Add missed connector_status check (Manasi) > > * Create i915_dsc_support node only for Gen >=10 (manasi) > > * Access intel_dp->dsc_dpcd only if its not NULL (Manasi) > > v3: > > * Combine Force_dsc_en with this patch (Ville) > > v2: > > * Use kstrtobool_from_user to avoid explicit error checking (Lyude) > > * Rebase on drm-tip (Manasi) > > > > 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 | 80 +++++++++++++++++++++++++++++ > > drivers/gpu/drm/i915/intel_dp.c | 3 +- > > drivers/gpu/drm/i915/intel_drv.h | 3 ++ > > 3 files changed, 85 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/gpu/drm/i915/i915_debugfs.c > > b/drivers/gpu/drm/i915/i915_debugfs.c > > index 129b9a6f8309..ec10ab027d18 100644 > > --- a/drivers/gpu/drm/i915/i915_debugfs.c > > +++ b/drivers/gpu/drm/i915/i915_debugfs.c > > @@ -5086,6 +5086,79 @@ static int i915_hdcp_sink_capability_show(struct > > seq_file *m, void *data) > > } > > DEFINE_SHOW_ATTRIBUTE(i915_hdcp_sink_capability); > > > > +static int i915_dsc_fec_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); I am seeing a kernel NULl pointer dereferencing here in CI possibly because the crtc is NULL and as per Ville and Danvet I should be grabbing both connection mutex and crtc mutex and use the acquire ctx and backoff stuff so I am trying to understand that part and seeing how I can use that. Let me know if you have any inputs/examples on that too.. > > + drm_modeset_lock(&crtc->base.mutex, NULL); > > + seq_printf(m, "DSC_Enabled: %s\n", > > + yesno(crtc_state->dsc_params.compression_enable)); > > + if (intel_dp->dsc_dpcd) > > + seq_printf(m, "DSC_Sink_Support: %s\n", > > + yesno(drm_dp_sink_supports_dsc(intel_dp- > > >dsc_dpcd))); > > + if (!intel_dp_is_edp(intel_dp)) > > + seq_printf(m, "FEC_Sink_Support: %s\n", > > + yesno(drm_dp_sink_supports_fec(intel_dp- > > >fec_capable))); > > + drm_modeset_unlock(&crtc->base.mutex); > > + > > + return 0; > > +} > > + > > +static ssize_t i915_dsc_fec_support_write(struct file *file, > > + const char __user *ubuf, > > + size_t len, loff_t *offp) > > +{ > > + bool dsc_enable = false; > > + int ret; > > + 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; > > + > > + DRM_DEBUG_DRIVER("Copied %d bytes from user to force DSC\n", > > + (unsigned int)len); > You can just use %zu instead of %d here, see: > > https://01.org/linuxgraphics/gfx-docs/drm/core-api/printk-formats.html Cool I will make this change. Thanks for the review. Regards Manasi > > Other then that, looks good to me! With that change: > > Reviewed-by: Lyude Paul <lyude@redhat.com> > > > + > > + ret = kstrtobool_from_user(ubuf, len, &dsc_enable); > > + if (ret < 0) > > + return ret; > > + > > + DRM_DEBUG_DRIVER("Got %s for DSC Enable\n", > > + (dsc_enable) ? "true" : "false"); > > + intel_dp->force_dsc_en = dsc_enable; > > + > > + *offp += len; > > + return len; > > +} > > + > > +static int i915_dsc_fec_support_open(struct inode *inode, > > + struct file *file) > > +{ > > + return single_open(file, i915_dsc_fec_support_show, > > + inode->i_private); > > +} > > + > > +static const struct file_operations i915_dsc_fec_support_fops = { > > + .owner = THIS_MODULE, > > + .open = i915_dsc_fec_support_open, > > + .read = seq_read, > > + .llseek = seq_lseek, > > + .release = single_release, > > + .write = i915_dsc_fec_support_write > > +}; > > + > > /** > > * i915_debugfs_connector_add - add i915 specific connector debugfs files > > * @connector: pointer to a registered drm_connector > > @@ -5098,6 +5171,7 @@ DEFINE_SHOW_ATTRIBUTE(i915_hdcp_sink_capability); > > int i915_debugfs_connector_add(struct drm_connector *connector) > > { > > struct dentry *root = connector->debugfs_entry; > > + struct drm_i915_private *dev_priv = to_i915(connector->dev); > > > > /* The connector must have been registered beforehands. */ > > if (!root) > > @@ -5122,5 +5196,11 @@ int i915_debugfs_connector_add(struct drm_connector > > *connector) > > connector, > > &i915_hdcp_sink_capability_fops); > > } > > > > + if (INTEL_GEN(dev_priv) >= 10 && > > + (connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort || > > + connector->connector_type == DRM_MODE_CONNECTOR_eDP)) > > + debugfs_create_file("i915_dsc_fec_support", S_IRUGO, root, > > + connector, &i915_dsc_fec_support_fops); > > + > > return 0; > > } > > diff --git a/drivers/gpu/drm/i915/intel_dp.c > > b/drivers/gpu/drm/i915/intel_dp.c > > index a6907a1761ab..2e3097cae277 100644 > > --- a/drivers/gpu/drm/i915/intel_dp.c > > +++ b/drivers/gpu/drm/i915/intel_dp.c > > @@ -2051,7 +2051,8 @@ intel_dp_compute_link_config(struct intel_encoder > > *encoder, > > &limits); > > > > /* enable compression if the mode doesn't fit available BW */ > > - if (!ret) { > > + DRM_DEBUG_KMS("Force DSC en = %d\n", intel_dp->force_dsc_en); > > + if (!ret || intel_dp->force_dsc_en) { > > if (!intel_dp_dsc_compute_config(intel_dp, pipe_config, > > conn_state, &limits)) > > return false; > > diff --git a/drivers/gpu/drm/i915/intel_drv.h > > b/drivers/gpu/drm/i915/intel_drv.h > > index f94a04b4ad87..0cedce438433 100644 > > --- a/drivers/gpu/drm/i915/intel_drv.h > > +++ b/drivers/gpu/drm/i915/intel_drv.h > > @@ -1209,6 +1209,9 @@ struct intel_dp { > > > > /* Displayport compliance testing */ > > struct intel_dp_compliance compliance; > > + > > + /* Display stream compression testing */ > > + bool force_dsc_en; > > }; > > > > enum lspcon_vendor { > -- > Cheers, > Lyude Paul >
On Wed, 2018-12-05 at 11:29 -0800, Manasi Navare wrote: > On Wed, Dec 05, 2018 at 02:00:39PM -0500, Lyude Paul wrote: > > Looks good, some small nitpicks > > > > On Tue, 2018-12-04 at 11:55 -0800, 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. > > > > > > force_dsc_en written through this debugfs node is used to force > > > DSC even for lower resolutions. > > > > > > v6: > > > * Read fec_capable only for non edp (Manasi) > > > v5: > > > * Name it dsc sink support and also add > > > fec support in the same node (Ville) > > > v4: > > > * Add missed connector_status check (Manasi) > > > * Create i915_dsc_support node only for Gen >=10 (manasi) > > > * Access intel_dp->dsc_dpcd only if its not NULL (Manasi) > > > v3: > > > * Combine Force_dsc_en with this patch (Ville) > > > v2: > > > * Use kstrtobool_from_user to avoid explicit error checking (Lyude) > > > * Rebase on drm-tip (Manasi) > > > > > > 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 | 80 +++++++++++++++++++++++++++++ > > > drivers/gpu/drm/i915/intel_dp.c | 3 +- > > > drivers/gpu/drm/i915/intel_drv.h | 3 ++ > > > 3 files changed, 85 insertions(+), 1 deletion(-) > > > > > > diff --git a/drivers/gpu/drm/i915/i915_debugfs.c > > > b/drivers/gpu/drm/i915/i915_debugfs.c > > > index 129b9a6f8309..ec10ab027d18 100644 > > > --- a/drivers/gpu/drm/i915/i915_debugfs.c > > > +++ b/drivers/gpu/drm/i915/i915_debugfs.c > > > @@ -5086,6 +5086,79 @@ static int i915_hdcp_sink_capability_show(struct > > > seq_file *m, void *data) > > > } > > > DEFINE_SHOW_ATTRIBUTE(i915_hdcp_sink_capability); > > > > > > +static int i915_dsc_fec_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); > > I am seeing a kernel NULl pointer dereferencing here in CI possibly because > the crtc is NULL and as per Ville and Danvet I should be grabbing both > connection mutex > and crtc mutex and use the acquire ctx and backoff stuff so I am trying to > understand that part > and seeing how I can use that. > > Let me know if you have any inputs/examples on that too.. Mhm, so here's why they are asking for each lock: connection_mutex: Protects any connector->state, and connector->status. (As an extra note: ignore connector->mutex for modesetting purposes, only dev->mode_config.connection_mutex is important.) crtc->mutex: Anything in crtc->state for the given crtc In order to avoid to avoid a NULL dereference due to connector->crtc->state changing, you'd start grabbing locks with something like this: /* pretend we have 'connector' already set to the drm_connector */ /* also pretend we have 'dev' set to the struct drm_device* */ struct drm_crtc *crtc; struct drm_modeset_acquire_ctx ctx; bool try_again = false; int ret = 0; drm_modeset_acquire_init(&ctx, 0); do { /* We don't check the return code here because since this is * our first lock, so there isn't any chance of us deadlocking * yet. */ drm_modeset_lock(&dev->mode_config.connection_mutex, &ctx); /* Cool! Now that we're holding connection_mutex, we can start * reading from the connector struct and friends */ crtc = connector->state->crtc; if (connector->status != connector_status_connected || !crtc) { ret = -ENODEV; break; } /* Now we need to check the return code from * drm_modeset_lock(), because....... */ ret = drm_modeset_lock(&crtc->mutex, &ctx); if (ret == -EDEADLK) { /* We could deadlock! If we're here, then this is * probably what happened: * * <CPU1> (us) <CPU2> * modeset_lock(&conn_mutex); modeset_lock(&crtc->mutex); * modeset_lock(&crtc->mutex); modeset_lock(&conn_mutex); * * CPU1 is waiting for crtc->mutex which is held by CPU2, but * CPU2 is waiting for conn_mutex, which is held by CPU1 * * Normally the kernel doesn't run into this issue * because a lot of care has been put into ordering * mutex_lock() calls correctly. But, with modesetting * we don't have the benefit of knowing what order these * locks will be acquired in. Since drm_modeset_lock() * has informed us of this scenario however, we can * avoid hanging the entire kernel by simply dropping * our locks, in this case that would just include * connection_mutex. We call this "backing off" */ drm_modeset_backoff(&ctx); /* Now, things will look like this: * * <CPU1> (us) <CPU2> * modeset_lock(&conn_mutex); modeset_lock(&crtc->mutex); * modeset_lock(&crtc->mutex); modeset_lock(&conn_mutex); * (oh no, a deadlock!) ... * modeset_backoff(); (Oh hey, I locked &conn_mutex) * modeset_lock(&conn_mutex); (now I'm doing stuff, wee!) * ... modeset_drop_locks(); * (Oh hey, I locked &conn_mutex) ... * (do stuff) ... * (etc. etc.) */ go_again = true; continue; } /* Now if we're here, we managed to grab both locks correctly, * and we know neither connector->state or crtc->state will * change. */ intel_dp = enc_to_intel_dp(intel_attached_encoder(connector)); if (intel_dp->dsc_dpcd) /* etc. etc. */ /* ... */ } while (go_again); /* Now, we can finally drop any locks we're holding */ drm_modeset_drop_locks(&ctx); /* And release our acquisition context */ drm_modeset_acquire_fini(&ctx); return ret; Does that help explain things? > > > > + drm_modeset_lock(&crtc->base.mutex, NULL); > > > + seq_printf(m, "DSC_Enabled: %s\n", > > > + yesno(crtc_state->dsc_params.compression_enable)); > > > + if (intel_dp->dsc_dpcd) > > > + seq_printf(m, "DSC_Sink_Support: %s\n", > > > + yesno(drm_dp_sink_supports_dsc(intel_dp- > > > > dsc_dpcd))); > > > + if (!intel_dp_is_edp(intel_dp)) > > > + seq_printf(m, "FEC_Sink_Support: %s\n", > > > + yesno(drm_dp_sink_supports_fec(intel_dp- > > > > fec_capable))); > > > + drm_modeset_unlock(&crtc->base.mutex); > > > + > > > + return 0; > > > +} > > > + > > > +static ssize_t i915_dsc_fec_support_write(struct file *file, > > > + const char __user *ubuf, > > > + size_t len, loff_t *offp) > > > +{ > > > + bool dsc_enable = false; > > > + int ret; > > > + 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; > > > + > > > + DRM_DEBUG_DRIVER("Copied %d bytes from user to force DSC\n", > > > + (unsigned int)len); > > You can just use %zu instead of %d here, see: > > > > https://01.org/linuxgraphics/gfx-docs/drm/core-api/printk-formats.html > > Cool I will make this change. Thanks for the review. > > Regards > Manasi > > > Other then that, looks good to me! With that change: > > > > Reviewed-by: Lyude Paul <lyude@redhat.com> > > > > > + > > > + ret = kstrtobool_from_user(ubuf, len, &dsc_enable); > > > + if (ret < 0) > > > + return ret; > > > + > > > + DRM_DEBUG_DRIVER("Got %s for DSC Enable\n", > > > + (dsc_enable) ? "true" : "false"); > > > + intel_dp->force_dsc_en = dsc_enable; > > > + > > > + *offp += len; > > > + return len; > > > +} > > > + > > > +static int i915_dsc_fec_support_open(struct inode *inode, > > > + struct file *file) > > > +{ > > > + return single_open(file, i915_dsc_fec_support_show, > > > + inode->i_private); > > > +} > > > + > > > +static const struct file_operations i915_dsc_fec_support_fops = { > > > + .owner = THIS_MODULE, > > > + .open = i915_dsc_fec_support_open, > > > + .read = seq_read, > > > + .llseek = seq_lseek, > > > + .release = single_release, > > > + .write = i915_dsc_fec_support_write > > > +}; > > > + > > > /** > > > * i915_debugfs_connector_add - add i915 specific connector debugfs > > > files > > > * @connector: pointer to a registered drm_connector > > > @@ -5098,6 +5171,7 @@ DEFINE_SHOW_ATTRIBUTE(i915_hdcp_sink_capability); > > > int i915_debugfs_connector_add(struct drm_connector *connector) > > > { > > > struct dentry *root = connector->debugfs_entry; > > > + struct drm_i915_private *dev_priv = to_i915(connector->dev); > > > > > > /* The connector must have been registered beforehands. */ > > > if (!root) > > > @@ -5122,5 +5196,11 @@ int i915_debugfs_connector_add(struct > > > drm_connector > > > *connector) > > > connector, > > > &i915_hdcp_sink_capability_fops); > > > } > > > > > > + if (INTEL_GEN(dev_priv) >= 10 && > > > + (connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort || > > > + connector->connector_type == DRM_MODE_CONNECTOR_eDP)) > > > + debugfs_create_file("i915_dsc_fec_support", S_IRUGO, root, > > > + connector, &i915_dsc_fec_support_fops); > > > + > > > return 0; > > > } > > > diff --git a/drivers/gpu/drm/i915/intel_dp.c > > > b/drivers/gpu/drm/i915/intel_dp.c > > > index a6907a1761ab..2e3097cae277 100644 > > > --- a/drivers/gpu/drm/i915/intel_dp.c > > > +++ b/drivers/gpu/drm/i915/intel_dp.c > > > @@ -2051,7 +2051,8 @@ intel_dp_compute_link_config(struct intel_encoder > > > *encoder, > > > &limits); > > > > > > /* enable compression if the mode doesn't fit available BW */ > > > - if (!ret) { > > > + DRM_DEBUG_KMS("Force DSC en = %d\n", intel_dp->force_dsc_en); > > > + if (!ret || intel_dp->force_dsc_en) { > > > if (!intel_dp_dsc_compute_config(intel_dp, pipe_config, > > > conn_state, &limits)) > > > return false; > > > diff --git a/drivers/gpu/drm/i915/intel_drv.h > > > b/drivers/gpu/drm/i915/intel_drv.h > > > index f94a04b4ad87..0cedce438433 100644 > > > --- a/drivers/gpu/drm/i915/intel_drv.h > > > +++ b/drivers/gpu/drm/i915/intel_drv.h > > > @@ -1209,6 +1209,9 @@ struct intel_dp { > > > > > > /* Displayport compliance testing */ > > > struct intel_dp_compliance compliance; > > > + > > > + /* Display stream compression testing */ > > > + bool force_dsc_en; > > > }; > > > > > > enum lspcon_vendor { > > -- > > Cheers, > > Lyude Paul > >
diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c index 129b9a6f8309..ec10ab027d18 100644 --- a/drivers/gpu/drm/i915/i915_debugfs.c +++ b/drivers/gpu/drm/i915/i915_debugfs.c @@ -5086,6 +5086,79 @@ static int i915_hdcp_sink_capability_show(struct seq_file *m, void *data) } DEFINE_SHOW_ATTRIBUTE(i915_hdcp_sink_capability); +static int i915_dsc_fec_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, "DSC_Enabled: %s\n", + yesno(crtc_state->dsc_params.compression_enable)); + if (intel_dp->dsc_dpcd) + seq_printf(m, "DSC_Sink_Support: %s\n", + yesno(drm_dp_sink_supports_dsc(intel_dp->dsc_dpcd))); + if (!intel_dp_is_edp(intel_dp)) + seq_printf(m, "FEC_Sink_Support: %s\n", + yesno(drm_dp_sink_supports_fec(intel_dp->fec_capable))); + drm_modeset_unlock(&crtc->base.mutex); + + return 0; +} + +static ssize_t i915_dsc_fec_support_write(struct file *file, + const char __user *ubuf, + size_t len, loff_t *offp) +{ + bool dsc_enable = false; + int ret; + 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; + + DRM_DEBUG_DRIVER("Copied %d bytes from user to force DSC\n", + (unsigned int)len); + + ret = kstrtobool_from_user(ubuf, len, &dsc_enable); + if (ret < 0) + return ret; + + DRM_DEBUG_DRIVER("Got %s for DSC Enable\n", + (dsc_enable) ? "true" : "false"); + intel_dp->force_dsc_en = dsc_enable; + + *offp += len; + return len; +} + +static int i915_dsc_fec_support_open(struct inode *inode, + struct file *file) +{ + return single_open(file, i915_dsc_fec_support_show, + inode->i_private); +} + +static const struct file_operations i915_dsc_fec_support_fops = { + .owner = THIS_MODULE, + .open = i915_dsc_fec_support_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, + .write = i915_dsc_fec_support_write +}; + /** * i915_debugfs_connector_add - add i915 specific connector debugfs files * @connector: pointer to a registered drm_connector @@ -5098,6 +5171,7 @@ DEFINE_SHOW_ATTRIBUTE(i915_hdcp_sink_capability); int i915_debugfs_connector_add(struct drm_connector *connector) { struct dentry *root = connector->debugfs_entry; + struct drm_i915_private *dev_priv = to_i915(connector->dev); /* The connector must have been registered beforehands. */ if (!root) @@ -5122,5 +5196,11 @@ int i915_debugfs_connector_add(struct drm_connector *connector) connector, &i915_hdcp_sink_capability_fops); } + if (INTEL_GEN(dev_priv) >= 10 && + (connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort || + connector->connector_type == DRM_MODE_CONNECTOR_eDP)) + debugfs_create_file("i915_dsc_fec_support", S_IRUGO, root, + connector, &i915_dsc_fec_support_fops); + return 0; } diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index a6907a1761ab..2e3097cae277 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -2051,7 +2051,8 @@ intel_dp_compute_link_config(struct intel_encoder *encoder, &limits); /* enable compression if the mode doesn't fit available BW */ - if (!ret) { + DRM_DEBUG_KMS("Force DSC en = %d\n", intel_dp->force_dsc_en); + if (!ret || intel_dp->force_dsc_en) { if (!intel_dp_dsc_compute_config(intel_dp, pipe_config, conn_state, &limits)) return false; diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index f94a04b4ad87..0cedce438433 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -1209,6 +1209,9 @@ struct intel_dp { /* Displayport compliance testing */ struct intel_dp_compliance compliance; + + /* Display stream compression testing */ + bool force_dsc_en; }; enum lspcon_vendor {
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. force_dsc_en written through this debugfs node is used to force DSC even for lower resolutions. v6: * Read fec_capable only for non edp (Manasi) v5: * Name it dsc sink support and also add fec support in the same node (Ville) v4: * Add missed connector_status check (Manasi) * Create i915_dsc_support node only for Gen >=10 (manasi) * Access intel_dp->dsc_dpcd only if its not NULL (Manasi) v3: * Combine Force_dsc_en with this patch (Ville) v2: * Use kstrtobool_from_user to avoid explicit error checking (Lyude) * Rebase on drm-tip (Manasi) 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 | 80 +++++++++++++++++++++++++++++ drivers/gpu/drm/i915/intel_dp.c | 3 +- drivers/gpu/drm/i915/intel_drv.h | 3 ++ 3 files changed, 85 insertions(+), 1 deletion(-)