drm/atomic: Allow drivers to subclass drm_atomic_state, v3
Drivers may need to store the state of shared resources, such as PLLs
or FIFO space, into the atomic state. Allow this by making it possible
to subclass drm_atomic_state.
Changes since v1:
- Change member names for functions to atomic_state_(alloc,clear)
- Change __drm_atomic_state_new to drm_atomic_state_init
- Allow free function to be overridden too, in case extra memory is
allocated in alloc.
Changes since v2:
- Rename *_default_free to default_release, to make clear it doesn't
free the state object itself.
Cc: dri-devel@lists.freedesktop.org
Acked-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index c6277a4..cd1b16b 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -30,7 +30,15 @@
#include <drm/drm_atomic.h>
#include <drm/drm_plane_helper.h>
-static void kfree_state(struct drm_atomic_state *state)
+/**
+ * drm_atomic_state_default_release -
+ * release memory initialized by drm_atomic_state_init
+ * @state: atomic state
+ *
+ * Free all the memory allocated by drm_atomic_state_init.
+ * This is useful for drivers that subclass the atomic state.
+ */
+void drm_atomic_state_default_release(struct drm_atomic_state *state)
{
kfree(state->connectors);
kfree(state->connector_states);
@@ -38,24 +46,20 @@
kfree(state->crtc_states);
kfree(state->planes);
kfree(state->plane_states);
- kfree(state);
}
+EXPORT_SYMBOL(drm_atomic_state_default_release);
/**
- * drm_atomic_state_alloc - allocate atomic state
+ * drm_atomic_state_init - init new atomic state
* @dev: DRM device
+ * @state: atomic state
*
- * This allocates an empty atomic state to track updates.
+ * Default implementation for filling in a new atomic state.
+ * This is useful for drivers that subclass the atomic state.
*/
-struct drm_atomic_state *
-drm_atomic_state_alloc(struct drm_device *dev)
+int
+drm_atomic_state_init(struct drm_device *dev, struct drm_atomic_state *state)
{
- struct drm_atomic_state *state;
-
- state = kzalloc(sizeof(*state), GFP_KERNEL);
- if (!state)
- return NULL;
-
/* TODO legacy paths should maybe do a better job about
* setting this appropriately?
*/
@@ -92,31 +96,50 @@
state->dev = dev;
- DRM_DEBUG_ATOMIC("Allocate atomic state %p\n", state);
+ DRM_DEBUG_ATOMIC("Allocated atomic state %p\n", state);
- return state;
+ return 0;
fail:
- kfree_state(state);
+ drm_atomic_state_default_release(state);
+ return -ENOMEM;
+}
+EXPORT_SYMBOL(drm_atomic_state_init);
- return NULL;
+/**
+ * drm_atomic_state_alloc - allocate atomic state
+ * @dev: DRM device
+ *
+ * This allocates an empty atomic state to track updates.
+ */
+struct drm_atomic_state *
+drm_atomic_state_alloc(struct drm_device *dev)
+{
+ struct drm_mode_config *config = &dev->mode_config;
+ struct drm_atomic_state *state;
+
+ if (!config->funcs->atomic_state_alloc) {
+ state = kzalloc(sizeof(*state), GFP_KERNEL);
+ if (!state)
+ return NULL;
+ if (drm_atomic_state_init(dev, state) < 0) {
+ kfree(state);
+ return NULL;
+ }
+ return state;
+ }
+
+ return config->funcs->atomic_state_alloc(dev);
}
EXPORT_SYMBOL(drm_atomic_state_alloc);
/**
- * drm_atomic_state_clear - clear state object
+ * drm_atomic_state_default_clear - clear base atomic state
* @state: atomic state
*
- * When the w/w mutex algorithm detects a deadlock we need to back off and drop
- * all locks. So someone else could sneak in and change the current modeset
- * configuration. Which means that all the state assembled in @state is no
- * longer an atomic update to the current state, but to some arbitrary earlier
- * state. Which could break assumptions the driver's ->atomic_check likely
- * relies on.
- *
- * Hence we must clear all cached state and completely start over, using this
- * function.
+ * Default implementation for clearing atomic state.
+ * This is useful for drivers that subclass the atomic state.
*/
-void drm_atomic_state_clear(struct drm_atomic_state *state)
+void drm_atomic_state_default_clear(struct drm_atomic_state *state)
{
struct drm_device *dev = state->dev;
struct drm_mode_config *config = &dev->mode_config;
@@ -162,6 +185,32 @@
state->plane_states[i] = NULL;
}
}
+EXPORT_SYMBOL(drm_atomic_state_default_clear);
+
+/**
+ * drm_atomic_state_clear - clear state object
+ * @state: atomic state
+ *
+ * When the w/w mutex algorithm detects a deadlock we need to back off and drop
+ * all locks. So someone else could sneak in and change the current modeset
+ * configuration. Which means that all the state assembled in @state is no
+ * longer an atomic update to the current state, but to some arbitrary earlier
+ * state. Which could break assumptions the driver's ->atomic_check likely
+ * relies on.
+ *
+ * Hence we must clear all cached state and completely start over, using this
+ * function.
+ */
+void drm_atomic_state_clear(struct drm_atomic_state *state)
+{
+ struct drm_device *dev = state->dev;
+ struct drm_mode_config *config = &dev->mode_config;
+
+ if (config->funcs->atomic_state_clear)
+ config->funcs->atomic_state_clear(state);
+ else
+ drm_atomic_state_default_clear(state);
+}
EXPORT_SYMBOL(drm_atomic_state_clear);
/**
@@ -173,14 +222,25 @@
*/
void drm_atomic_state_free(struct drm_atomic_state *state)
{
+ struct drm_device *dev;
+ struct drm_mode_config *config;
+
if (!state)
return;
+ dev = state->dev;
+ config = &dev->mode_config;
+
drm_atomic_state_clear(state);
DRM_DEBUG_ATOMIC("Freeing atomic state %p\n", state);
- kfree_state(state);
+ if (config->funcs->atomic_state_free) {
+ config->funcs->atomic_state_free(state);
+ } else {
+ drm_atomic_state_default_release(state);
+ kfree(state);
+ }
}
EXPORT_SYMBOL(drm_atomic_state_free);
diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h
index d785430..f0d3a73 100644
--- a/include/drm/drm_atomic.h
+++ b/include/drm/drm_atomic.h
@@ -35,6 +35,11 @@
void drm_atomic_state_clear(struct drm_atomic_state *state);
void drm_atomic_state_free(struct drm_atomic_state *state);
+int __must_check
+drm_atomic_state_init(struct drm_device *dev, struct drm_atomic_state *state);
+void drm_atomic_state_default_clear(struct drm_atomic_state *state);
+void drm_atomic_state_default_release(struct drm_atomic_state *state);
+
struct drm_crtc_state * __must_check
drm_atomic_get_crtc_state(struct drm_atomic_state *state,
struct drm_crtc *crtc);
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 5626191..37c44f2 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -979,6 +979,9 @@
* @atomic_check: check whether a given atomic state update is possible
* @atomic_commit: commit an atomic state update previously verified with
* atomic_check()
+ * @atomic_state_alloc: allocate a new atomic state
+ * @atomic_state_clear: clear the atomic state
+ * @atomic_state_free: free the atomic state
*
* Some global (i.e. not per-CRTC, connector, etc) mode setting functions that
* involve drivers.
@@ -994,6 +997,9 @@
int (*atomic_commit)(struct drm_device *dev,
struct drm_atomic_state *a,
bool async);
+ struct drm_atomic_state *(*atomic_state_alloc)(struct drm_device *dev);
+ void (*atomic_state_clear)(struct drm_atomic_state *state);
+ void (*atomic_state_free)(struct drm_atomic_state *state);
};
/**