Commit 036ef573 authored by Maarten Lankhorst's avatar Maarten Lankhorst Committed by Daniel Vetter
Browse files

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: default avatarAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Signed-off-by: default avatarMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
parent 744b0588

drivers/gpu/drm/drm_atomic.c

+88 −28
Original line number Diff line number Diff line
@@ -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 @@ static void kfree_state(struct drm_atomic_state *state) 
	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 @@ drm_atomic_state_alloc(struct drm_device *dev) 


	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);



/**

 * 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 @@ void drm_atomic_state_clear(struct drm_atomic_state *state) 
		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 @@ EXPORT_SYMBOL(drm_atomic_state_clear); 
 */

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);

include/drm/drm_atomic.h

+5 −0
Original line number Diff line number Diff line
@@ -35,6 +35,11 @@ drm_atomic_state_alloc(struct drm_device *dev); 
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);

include/drm/drm_crtc.h

+6 −0
Original line number Diff line number Diff line
@@ -979,6 +979,9 @@ struct drm_mode_set { 
 * @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 @@ struct drm_mode_config_funcs { 
	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);

};



/**

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