diff options
| -rw-r--r-- | Documentation/gpu/drm-kms-helpers.rst | 12 | ||||
| -rw-r--r-- | drivers/gpu/drm/Makefile | 3 | ||||
| -rw-r--r-- | drivers/gpu/drm/drm_gem_atomic_helper.c | 208 | ||||
| -rw-r--r-- | include/drm/drm_gem_atomic_helper.h | 73 |
4 files changed, 295 insertions, 1 deletions
diff --git a/Documentation/gpu/drm-kms-helpers.rst b/Documentation/gpu/drm-kms-helpers.rst index b89ddd06dabb..389892f36185 100644 --- a/Documentation/gpu/drm-kms-helpers.rst +++ b/Documentation/gpu/drm-kms-helpers.rst @@ -80,6 +80,18 @@ Atomic State Helper Reference .. kernel-doc:: drivers/gpu/drm/drm_atomic_state_helper.c :export: +GEM Atomic Helper Reference +--------------------------- + +.. kernel-doc:: drivers/gpu/drm/drm_gem_atomic_helper.c + :doc: overview + +.. kernel-doc:: include/drm/drm_gem_atomic_helper.h + :internal: + +.. kernel-doc:: drivers/gpu/drm/drm_gem_atomic_helper.c + :export: + Simple KMS Helper Reference =========================== diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile index 926adef289db..02c229392345 100644 --- a/drivers/gpu/drm/Makefile +++ b/drivers/gpu/drm/Makefile @@ -44,7 +44,8 @@ drm_kms_helper-y := drm_bridge_connector.o drm_crtc_helper.o drm_dp_helper.o \ drm_plane_helper.o drm_dp_mst_topology.o drm_atomic_helper.o \ drm_kms_helper_common.o drm_dp_dual_mode_helper.o \ drm_simple_kms_helper.o drm_modeset_helper.o \ - drm_scdc_helper.o drm_gem_framebuffer_helper.o \ + drm_scdc_helper.o drm_gem_atomic_helper.o \ + drm_gem_framebuffer_helper.o \ drm_atomic_state_helper.o drm_damage_helper.o \ drm_format_helper.o drm_self_refresh_helper.o diff --git a/drivers/gpu/drm/drm_gem_atomic_helper.c b/drivers/gpu/drm/drm_gem_atomic_helper.c new file mode 100644 index 000000000000..e27762cef360 --- /dev/null +++ b/drivers/gpu/drm/drm_gem_atomic_helper.c @@ -0,0 +1,208 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include <drm/drm_atomic_state_helper.h> +#include <drm/drm_gem_atomic_helper.h> +#include <drm/drm_gem_framebuffer_helper.h> +#include <drm/drm_simple_kms_helper.h> + +#include "drm_internal.h" + +/** + * DOC: overview + * + * The GEM atomic helpers library implements generic atomic-commit + * functions for drivers that use GEM objects. Currently, it provides + * plane state and framebuffer BO mappings for planes with shadow + * buffers. + */ + +/* + * Shadow-buffered Planes + */ + +static struct drm_plane_state * +drm_gem_duplicate_shadow_plane_state(struct drm_plane *plane) +{ + struct drm_plane_state *plane_state = plane->state; + struct drm_shadow_plane_state *new_shadow_plane_state; + + if (!plane_state) + return NULL; + + new_shadow_plane_state = kzalloc(sizeof(*new_shadow_plane_state), GFP_KERNEL); + if (!new_shadow_plane_state) + return NULL; + __drm_atomic_helper_plane_duplicate_state(plane, &new_shadow_plane_state->base); + + return &new_shadow_plane_state->base; +} + +static void drm_gem_destroy_shadow_plane_state(struct drm_plane *plane, + struct drm_plane_state *plane_state) +{ + struct drm_shadow_plane_state *shadow_plane_state = + to_drm_shadow_plane_state(plane_state); + + __drm_atomic_helper_plane_destroy_state(&shadow_plane_state->base); + kfree(shadow_plane_state); +} + +static void drm_gem_reset_shadow_plane(struct drm_plane *plane) +{ + struct drm_shadow_plane_state *shadow_plane_state; + + if (plane->state) { + drm_gem_destroy_shadow_plane_state(plane, plane->state); + plane->state = NULL; /* must be set to NULL here */ + } + + shadow_plane_state = kzalloc(sizeof(*shadow_plane_state), GFP_KERNEL); + if (!shadow_plane_state) + return; + __drm_atomic_helper_plane_reset(plane, &shadow_plane_state->base); +} + +static int drm_gem_prepare_shadow_fb(struct drm_plane *plane, struct drm_plane_state *plane_state) +{ + struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state); + struct drm_framebuffer *fb = plane_state->fb; + struct drm_gem_object *obj; + struct dma_buf_map map; + int ret; + size_t i; + + if (!fb) + return 0; + + ret = drm_gem_fb_prepare_fb(plane, plane_state); + if (ret) + return ret; + + for (i = 0; i < ARRAY_SIZE(shadow_plane_state->map); ++i) { + obj = drm_gem_fb_get_obj(fb, i); + if (!obj) + continue; + ret = drm_gem_vmap(obj, &map); + if (ret) + goto err_drm_gem_vunmap; + shadow_plane_state->map[i] = map; + } + + return 0; + +err_drm_gem_vunmap: + while (i) { + --i; + obj = drm_gem_fb_get_obj(fb, i); + if (!obj) + continue; + drm_gem_vunmap(obj, &shadow_plane_state->map[i]); + } + return ret; +} + +static void drm_gem_cleanup_shadow_fb(struct drm_plane *plane, struct drm_plane_state *plane_state) +{ + struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state); + struct drm_framebuffer *fb = plane_state->fb; + size_t i = ARRAY_SIZE(shadow_plane_state->map); + struct drm_gem_object *obj; + + if (!fb) + return; + + while (i) { + --i; + obj = drm_gem_fb_get_obj(fb, i); + if (!obj) + continue; + drm_gem_vunmap(obj, &shadow_plane_state->map[i]); + } +} + +/** + * drm_gem_simple_kms_prepare_shadow_fb - prepares shadow framebuffers + * @pipe: the simple display pipe + * @plane_state: the plane state of type struct drm_shadow_plane_state + * + * This function implements struct drm_simple_display_funcs.prepare_fb. It + * maps all buffer objects of the plane's framebuffer into kernel address + * space and stores them in struct drm_shadow_plane_state.map. The + * framebuffer will be synchronized as part of the atomic commit. + * + * See drm_gem_simple_kms_cleanup_shadow_fb() for cleanup. + * + * Returns: + * 0 on success, or a negative errno code otherwise. + */ +int drm_gem_simple_kms_prepare_shadow_fb(struct drm_simple_display_pipe *pipe, + struct drm_plane_state *plane_state) +{ + return drm_gem_prepare_shadow_fb(&pipe->plane, plane_state); +} +EXPORT_SYMBOL(drm_gem_simple_kms_prepare_shadow_fb); + +/** + * drm_gem_simple_kms_cleanup_shadow_fb - releases shadow framebuffers + * @pipe: the simple display pipe + * @plane_state: the plane state of type struct drm_shadow_plane_state + * + * This function implements struct drm_simple_display_funcs.cleanup_fb. + * This function unmaps all buffer objects of the plane's framebuffer. + * + * See drm_gem_simple_kms_prepare_shadow_fb(). + */ +void drm_gem_simple_kms_cleanup_shadow_fb(struct drm_simple_display_pipe *pipe, + struct drm_plane_state *plane_state) +{ + drm_gem_cleanup_shadow_fb(&pipe->plane, plane_state); +} +EXPORT_SYMBOL(drm_gem_simple_kms_cleanup_shadow_fb); + +/** + * drm_gem_simple_kms_reset_shadow_plane - resets a shadow-buffered plane + * @pipe: the simple display pipe + * + * This function implements struct drm_simple_display_funcs.reset_plane + * for shadow-buffered planes. + */ +void drm_gem_simple_kms_reset_shadow_plane(struct drm_simple_display_pipe *pipe) +{ + drm_gem_reset_shadow_plane(&pipe->plane); +} +EXPORT_SYMBOL(drm_gem_simple_kms_reset_shadow_plane); + +/** + * drm_gem_simple_kms_duplicate_shadow_plane_state - duplicates shadow-buffered plane state + * @pipe: the simple display pipe + * + * This function implements struct drm_simple_display_funcs.duplicate_plane_state + * for shadow-buffered planes. It does not duplicate existing mappings of the shadow + * buffers. Mappings are maintained during the atomic commit by the plane's prepare_fb + * and cleanup_fb helpers. + * + * Returns: + * A pointer to a new plane state on success, or NULL otherwise. + */ +struct drm_plane_state * +drm_gem_simple_kms_duplicate_shadow_plane_state(struct drm_simple_display_pipe *pipe) +{ + return drm_gem_duplicate_shadow_plane_state(&pipe->plane); +} +EXPORT_SYMBOL(drm_gem_simple_kms_duplicate_shadow_plane_state); + +/** + * drm_gem_simple_kms_destroy_shadow_plane_state - resets shadow-buffered plane state + * @pipe: the simple display pipe + * @plane_state: the plane state of type struct drm_shadow_plane_state + * + * This function implements struct drm_simple_display_funcs.destroy_plane_state + * for shadow-buffered planes. It expects that mappings of shadow buffers + * have been released already. + */ +void drm_gem_simple_kms_destroy_shadow_plane_state(struct drm_simple_display_pipe *pipe, + struct drm_plane_state *plane_state) +{ + drm_gem_destroy_shadow_plane_state(&pipe->plane, plane_state); +} +EXPORT_SYMBOL(drm_gem_simple_kms_destroy_shadow_plane_state); diff --git a/include/drm/drm_gem_atomic_helper.h b/include/drm/drm_gem_atomic_helper.h new file mode 100644 index 000000000000..08b96ccea325 --- /dev/null +++ b/include/drm/drm_gem_atomic_helper.h @@ -0,0 +1,73 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ + +#ifndef __DRM_GEM_ATOMIC_HELPER_H__ +#define __DRM_GEM_ATOMIC_HELPER_H__ + +#include <linux/dma-buf-map.h> + +#include <drm/drm_plane.h> + +struct drm_simple_display_pipe; + +/* + * Helpers for planes with shadow buffers + */ + +/** + * struct drm_shadow_plane_state - plane state for planes with shadow buffers + * + * For planes that use a shadow buffer, struct drm_shadow_plane_state + * provides the regular plane state plus mappings of the shadow buffer + * into kernel address space. + */ +struct drm_shadow_plane_state { + /** @base: plane state */ + struct drm_plane_state base; + + /* Transitional state - do not export or duplicate */ + + /** + * @map: Mappings of the plane's framebuffer BOs in to kernel address space + * + * The memory mappings stored in map should be established in the plane's + * prepare_fb callback and removed in the cleanup_fb callback. + */ + struct dma_buf_map map[4]; +}; + +/** + * to_drm_shadow_plane_state - upcasts from struct drm_plane_state + * @state: the plane state + */ +static inline struct drm_shadow_plane_state * +to_drm_shadow_plane_state(struct drm_plane_state *state) +{ + return container_of(state, struct drm_shadow_plane_state, base); +} + +int drm_gem_simple_kms_prepare_shadow_fb(struct drm_simple_display_pipe *pipe, + struct drm_plane_state *plane_state); +void drm_gem_simple_kms_cleanup_shadow_fb(struct drm_simple_display_pipe *pipe, + struct drm_plane_state *plane_state); +void drm_gem_simple_kms_reset_shadow_plane(struct drm_simple_display_pipe *pipe); +struct drm_plane_state * +drm_gem_simple_kms_duplicate_shadow_plane_state(struct drm_simple_display_pipe *pipe); +void drm_gem_simple_kms_destroy_shadow_plane_state(struct drm_simple_display_pipe *pipe, + struct drm_plane_state *plane_state); + +/** + * DRM_GEM_SIMPLE_DISPLAY_PIPE_SHADOW_PLANE_FUNCS - + * Initializes struct drm_simple_display_pipe_funcs for shadow-buffered planes + * + * Drivers may use GEM BOs as shadow buffers over the framebuffer memory. This + * macro initializes struct drm_simple_display_pipe_funcs to use the rsp helper + * functions. + */ +#define DRM_GEM_SIMPLE_DISPLAY_PIPE_SHADOW_PLANE_FUNCS \ + .prepare_fb = drm_gem_simple_kms_prepare_shadow_fb, \ + .cleanup_fb = drm_gem_simple_kms_cleanup_shadow_fb, \ + .reset_plane = drm_gem_simple_kms_reset_shadow_plane, \ + .duplicate_plane_state = drm_gem_simple_kms_duplicate_shadow_plane_state, \ + .destroy_plane_state = drm_gem_simple_kms_destroy_shadow_plane_state + +#endif /* __DRM_GEM_ATOMIC_HELPER_H__ */ |