Introduce a DRM interface for DRM clients to further restrict the
VRR Range within the panel supported VRR range on a per-commit
basis.
The goal is to give DRM client the ability to do frame-doubling/
ramping themselves, or to set lower static refresh rates for power
savings.
This is done through 2 new CRTC properties, along with a client
cap. See the docstrings in patch for details.
This RFC doesn't include a driver-side implementation yet; that is
coming soon. Currently, looking to get some comments on whether this
interface makes sense for both compositor and drivers
---
drivers/gpu/drm/drm_atomic_uapi.c | 30 +++++++++++++++++++++---
drivers/gpu/drm/drm_connector.c | 25 ++++++++++++++++++++
drivers/gpu/drm/drm_file.c | 2 ++
drivers/gpu/drm/drm_ioctl.c | 7 ++++++
drivers/gpu/drm/drm_mode_config.c | 14 ++++++++++++
include/drm/drm_connector.h | 1 +
include/drm/drm_crtc.h | 38 +++++++++++++++++++++++++++++++
include/drm/drm_file.h | 10 ++++++++
include/drm/drm_mode_config.h | 18 +++++++++++++++
include/uapi/drm/drm.h | 17 ++++++++++++++
10 files changed, 159 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/drm_atomic_uapi.c
b/drivers/gpu/drm/drm_atomic_uapi.c
index 85dbdaa4a2e2..73f929cff4e1 100644
--- a/drivers/gpu/drm/drm_atomic_uapi.c
+++ b/drivers/gpu/drm/drm_atomic_uapi.c
@@ -365,8 +365,8 @@ static s32 __user *get_out_fence_for_connector(struct
drm_atomic_state *state,
}
static int drm_atomic_crtc_set_property(struct drm_crtc *crtc,
- struct drm_crtc_state *state, struct drm_property *property,
- uint64_t val)
+ struct drm_crtc_state *state, struct drm_file *file_priv,
+ struct drm_property *property, uint64_t val)
{
struct drm_device *dev = crtc->dev;
struct drm_mode_config *config = &dev->mode_config;
@@ -421,6 +421,26 @@ static int drm_atomic_crtc_set_property(struct drm_crtc
*crtc,
state->scaling_filter = val;
} else if (crtc->funcs->atomic_set_property) {
return crtc->funcs->atomic_set_property(crtc, state, property,
val);
+ } else if (property == config->prop_vrr_range_control_min) {
+ if (file_priv->vrr_range_control) {
+ drm_dbg_atomic(dev, "Setting vrr_range_min crtc
property not"
+ "permitted with
DRM_CLIENT_CAP_VRR_RANGE_CONTROL"
+ "client cap\n");
+ return -EINVAL;
+ }
+ if (!val)
+ return -EINVAL;
+ state->vrr_range_min = val;
+ } else if (property == config->prop_vrr_range_control_max) {
+ if (file_priv->vrr_range_control) {
+ drm_dbg_atomic(dev,"Setting vrr_range_max crtc property
not"
+ "permitted with
DRM_CLIENT_CAP_VRR_RANGE_CONTROL"
+ "client cap\n");
+ return -EINVAL;
+ }
+ if (!val)
+ return -EINVAL;
+ state->vrr_range_max = val;
} else {
drm_dbg_atomic(crtc->dev,
"[CRTC:%d:%s] unknown property [PROP:%d:%s]\n",
@@ -446,6 +466,10 @@ drm_atomic_crtc_get_property(struct drm_crtc *crtc,
*val = (state->mode_blob) ? state->mode_blob->base.id : 0;
else if (property == config->prop_vrr_enabled)
*val = state->vrr_enabled;
+ else if (property == config->prop_vrr_range_control_min)
+ *val = state->vrr_range_min;
+ else if (property == config->prop_vrr_range_control_max)
+ *val = state->vrr_range_max;
else if (property == config->degamma_lut_property)
*val = (state->degamma_lut) ? state->degamma_lut->base.id : 0;
else if (property == config->ctm_property)
@@ -1062,7 +1086,7 @@ int drm_atomic_set_property(struct drm_atomic_state
*state,
}
ret = drm_atomic_crtc_set_property(crtc,
- crtc_state, prop, prop_value);
+ crtc_state, file_priv, prop, prop_value);
break;
}
case DRM_MODE_OBJECT_PLANE: {
diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index 272d6254ea47..dc4b50ff5fe0 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -2866,6 +2866,31 @@ int
drm_connector_attach_hdr_output_metadata_property(struct drm_connector *conn
}
EXPORT_SYMBOL(drm_connector_attach_hdr_output_metadata_property);
+/**
+ * drm_connector_attach_vrr_range_control_property - attach
"VRR_RANGE_CONTROL_MIN" and
+ * "VRR_RANGE_CONTROL_MAX" property
+ *
+ * @connector: connector to attach the property on.
+ *
+ * This is used to allow the userspace to send VRR range control min and max
value to the
+ * driver.
+ *
+ * Returns:
+ * Zero on success, negative errno on failure.
+ */
+int drm_connector_attach_vrr_range_control_property(struct drm_connector
*connector)
+{
+ struct drm_device *dev = connector->dev;
+ struct drm_property *prop_min =
dev->mode_config.prop_vrr_range_control_min;
+ struct drm_property *prop_max =
dev->mode_config.prop_vrr_range_control_max;
+
+ drm_object_attach_property(&connector->base, prop_min, 0);
+ drm_object_attach_property(&connector->base, prop_max, 0);
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_connector_attach_vrr_range_control_property);
+
/**
* drm_connector_attach_broadcast_rgb_property - attach "Broadcast RGB"
property
* @connector: connector to attach the property on.
diff --git a/drivers/gpu/drm/drm_file.c b/drivers/gpu/drm/drm_file.c
index eebd1a05ee97..7ed28e94544a 100644
--- a/drivers/gpu/drm/drm_file.c
+++ b/drivers/gpu/drm/drm_file.c
@@ -157,6 +157,8 @@ struct drm_file *drm_file_alloc(struct drm_minor *minor)
init_waitqueue_head(&file->event_wait);
file->event_space = 4096; /* set aside 4k for event buffer */
+ file->vrr_range_control = false; /* set as false for init */
+
spin_lock_init(&file->master_lookup_lock);
mutex_init(&file->event_read_lock);
mutex_init(&file->client_name_lock);
diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c
index d8a24875a7ba..273139688ba1 100644
--- a/drivers/gpu/drm/drm_ioctl.c
+++ b/drivers/gpu/drm/drm_ioctl.c
@@ -373,6 +373,13 @@ drm_setclientcap(struct drm_device *dev, void *data,
struct drm_file *file_priv)
return -EINVAL;
file_priv->supports_virtualized_cursor_plane = req->value;
break;
+ case DRM_CLIENT_CAP_VRR_RANGE_CONTROL:
+ if (!file_priv->atomic)
+ return -EINVAL;
+ if (req->value == 0)
+ return -EINVAL;
+ file_priv->vrr_range_control = req->value;
+ break;
default:
return -EINVAL;
}
diff --git a/drivers/gpu/drm/drm_mode_config.c
b/drivers/gpu/drm/drm_mode_config.c
index 25f376869b3a..1f74284208c6 100644
--- a/drivers/gpu/drm/drm_mode_config.c
+++ b/drivers/gpu/drm/drm_mode_config.c
@@ -340,6 +340,20 @@ static int drm_mode_create_standard_properties(struct
drm_device *dev)
return -ENOMEM;
dev->mode_config.prop_vrr_enabled = prop;
+ prop = drm_property_create_range(dev,
+ DRM_MODE_PROP_ATOMIC | DRM_MODE_PROP_RANGE,
+ "VRR-RANGE-CONTROL-MIN", 0, UINT_MAX);
+ if (!prop)
+ return -ENOMEM;
+ dev->mode_config.prop_vrr_range_control_min = prop;
+
+ prop = drm_property_create_range(dev,
+ DRM_MODE_PROP_ATOMIC | DRM_MODE_PROP_RANGE,
+ "VRR-RANGE-CONTROL-MAX", 0, UINT_MAX);
+ if (!prop)
+ return -ENOMEM;
+ dev->mode_config.prop_vrr_range_control_max = prop;
+
prop = drm_property_create(dev,
DRM_MODE_PROP_BLOB,
"DEGAMMA_LUT", 0);
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index 8f34f4b8183d..dd2c3337235a 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -2451,6 +2451,7 @@ int drm_connector_attach_vrr_capable_property(
int drm_connector_attach_broadcast_rgb_property(struct drm_connector
*connector);
int drm_connector_attach_colorspace_property(struct drm_connector *connector);
int drm_connector_attach_hdr_output_metadata_property(struct drm_connector
*connector);
+int drm_connector_attach_vrr_range_control_property(struct drm_connector
*connector);
bool drm_connector_atomic_hdr_metadata_equal(struct drm_connector_state
*old_state,
struct drm_connector_state
*new_state);
int drm_mode_create_aspect_ratio_property(struct drm_device *dev);
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index caa56e039da2..39d1bf66f713 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -299,6 +299,44 @@ struct drm_crtc_state {
*/
bool vrr_enabled;
+ /** @vrr_range_min:
+ *
+ * This is desired minimal FPS number.
+ *
+ * Default state is 'vrr_range_min = 0', (and 'vrr_range_max = 0'),
+ * indicating legacy VRR_ENABLED behavior. if both are set to a non-zeo
+ * value, the new VRR range control behavior will be active. See
+ * &DRM_CLIENT_CAP_VRR_RANGE_CONTROL.
+ *
+ * If setting a non-zero value, the driver should check that:
+ *
+ * 1. Both vrr_range_min and vrr_range_max are set to a non-zero value.
+ * This indicates the driver to switch the new VRR range control
+ * behavior.
+ * 2. Both vrr_rage_min and vrr_range_max are within the panel's
supported
+ * FPS range.
+ * 3. vrr_range_min is less-than-or-equal-to vrr_range_max.
+ */
+ uint16_t vrr_range_min;
+
+ /** @vrr_range_max:
+ *
+ * Default state is 'vrr_range_max = 0', (and 'vrr_range_min = 0'),
+ * indicating legacy VRR_ENABLED behavior. if both are set to a non-zeo
+ * value, the new VRR range control behavior will be active. See
+ * &DRM_CLIENT_CAP_VRR_RANGE_CONTROL.
+ *
+ * If setting a non-zero value, the driver should check that:
+ *
+ * 1. Both vrr_range_min and vrr_range_max are set to a non-zero value.
+ * This indicates the driver to switch the new VRR range control
+ * behavior.
+ * 2. Both vrr_rage_min and vrr_range_max are within the panel's
supported
+ * FPS range.
+ * 3. vrr_range_min is less-than-or-equal-to vrr_range_max.
+ */
+ uint16_t vrr_range_max;
+
/**
* @self_refresh_active:
*
diff --git a/include/drm/drm_file.h b/include/drm/drm_file.h
index 115763799625..4cb57a503a02 100644
--- a/include/drm/drm_file.h
+++ b/include/drm/drm_file.h
@@ -240,6 +240,16 @@ struct drm_file {
*/
bool supports_virtualized_cursor_plane;
+ /**
+ * @vrr_range_control:
+ *
+ * If set to true, the DRM driver will allow setting of the
+ * &drm_mode_config.prop_vrr_range_control_min_property and
+ * &drm_mode_config.prop_vrr_range_control_max_property CRTC
+ * properties, if the properties are supported by the driver.
+ */
+ bool vrr_range_control;
+
/**
* @master:
*
diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h
index 2e848b816218..e02dd46ca5c2 100644
--- a/include/drm/drm_mode_config.h
+++ b/include/drm/drm_mode_config.h
@@ -680,6 +680,24 @@ struct drm_mode_config {
*/
struct drm_property *prop_vrr_enabled;
+ /**
+ * @prop_vrr_range_control_min_property: Optional CRTC properties to
+ * further limit the minimum allowed refresh rate within the panel's
+ * supported refresh rate range. It's invalid to set unless the
+ * client advertises &DRM_CLIENT_CAP_VRR_RANGE_CONTROL.
+ * See also &drm_ctrc_state.vrr_range_min.
+ */
+ struct drm_property *prop_vrr_range_control_min;
+
+ /**
+ * @prop_vrr_range_control_max_property: Optional CRTC properties to
+ * further limit the maximum allowed refresh rate within the panel's
+ * supported refresh rate range. It's invalid to set unless the
+ * client advertises &DRM_CLIENT_CAP_VRR_RANGE_CONTROL.
+ * See also &drm_ctrc_state.vrr_range_max.
+ */
+ struct drm_property *prop_vrr_range_control_max;
+
/**
* @dvi_i_subconnector_property: Optional DVI-I property to
* differentiate between analog or digital mode.
diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h
index 3cd5cf15e3c9..e4d918342e67 100644
--- a/include/uapi/drm/drm.h
+++ b/include/uapi/drm/drm.h
@@ -906,6 +906,23 @@ struct drm_get_cap {
*/
#define DRM_CLIENT_CAP_CURSOR_PLANE_HOTSPOT 6
+/**
+ * DRM_CLIENT_CAP_VRR_RANGE_CONTROL
+ *
+ * The driver shall not program a refresh rate that is:
+ * - Below the &drm_crtc_state.vrr_range_min, nor
+ * - Above the &drm_crtc_state.vrr_range_max
+ * Even if the panel supports a wider range than the range requested.
+ *
+ * Once set, the driver will allow setting of the
+ *
+ * - &drm_mode_config.prop_vrr_range_control_min and
+ * - &drm_mode_config.prop_vrr_range_control_max properties.
+ *
+ * Otherwise, setting them will be invalid.
+ */
+#define DRM_CLIENT_CAP_VRR_RANGE_CONTROL 7
+
/* DRM_IOCTL_SET_CLIENT_CAP ioctl argument type */
struct drm_set_client_cap {
__u64 capability;
--
2.43.0
