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SPAMHAUS_XBL(0.00)[2a07:de40:b281:104:10:150:64:97:from]; DKIM_TRACE(0.00)[suse.de:+] X-Spam-Flag: NO Am 08.09.26 um 16:35 schrieb Maxime Ripard: > From: Sebastian Wick > > Userspace currently has no atomic way to reset all KMS object states > to their defaults. To bring a display pipeline to a known state, a > compositor must explicitly set every property on every object, which > requires tracking which properties exist and what their defaults are. > > Introduce DRM_MODE_ATOMIC_RESET (0x0800) which, when passed to the > atomic ioctl, fills the commit with default states for all KMS > objects before applying the properties supplied in the request. > Properties not explicitly included in the commit remain at their > defaults (CRTCs inactive, planes disabled, connectors unbound, and > so on). > > The flag cannot be combined with DRM_MODE_PAGE_FLIP_ASYNC, since a > full state reset is incompatible with an async flip. > > Signed-off-by: Sebastian Wick > Co-developed-by: Maxime Ripard > Signed-off-by: Maxime Ripard Reviewed-by: Thomas Zimmermann > --- > drivers/gpu/drm/drm_atomic.c | 3 +++ > drivers/gpu/drm/drm_atomic_uapi.c | 13 +++++++++++++ > drivers/gpu/drm/drm_ioctl.c | 3 +++ > include/uapi/drm/drm.h | 10 ++++++++++ > include/uapi/drm/drm_mode.h | 14 +++++++++++++- > 5 files changed, 42 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c > index 4c15757308d6..d5b3a7d99239 100644 > --- a/drivers/gpu/drm/drm_atomic.c > +++ b/drivers/gpu/drm/drm_atomic.c > @@ -1625,10 +1625,13 @@ EXPORT_SYMBOL(drm_atomic_get_new_bridge_state); > * the current state. > * > * Color operations are not checked because they always use > * drm_atomic_helper_colorop_create_state() and do not have a per-driver hook. > * > + * This is used to report the %DRM_CAP_ATOMIC_RESET capability to userspace, > + * and as a precondition in drm_atomic_commit_fill_with_defaults(). > + * > * Returns: > * True if all objects implement atomic_create_state, false otherwise. > */ > bool drm_atomic_can_create_state(struct drm_device *dev) > { > diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c > index d52504d823bc..fe794a65a727 100644 > --- a/drivers/gpu/drm/drm_atomic_uapi.c > +++ b/drivers/gpu/drm/drm_atomic_uapi.c > @@ -1665,10 +1665,17 @@ int drm_mode_atomic_ioctl(struct drm_device *dev, > drm_dbg_atomic(dev, > "commit failed: page-flip event requested with test-only commit\n"); > return -EINVAL; > } > > + if ((arg->flags & DRM_MODE_ATOMIC_RESET) && > + (arg->flags & DRM_MODE_PAGE_FLIP_ASYNC)) { > + drm_dbg_atomic(dev, > + "commit failed: reset cannot be combined with async flip\n"); > + return -EINVAL; > + } > + > state = drm_atomic_commit_alloc(dev); > if (!state) > return -ENOMEM; > > drm_modeset_acquire_init(&ctx, DRM_MODESET_ACQUIRE_INTERRUPTIBLE); > @@ -1680,10 +1687,16 @@ int drm_mode_atomic_ioctl(struct drm_device *dev, > copied_objs = 0; > copied_props = 0; > fence_state = NULL; > num_fences = 0; > > + if (arg->flags & DRM_MODE_ATOMIC_RESET) { > + ret = drm_atomic_commit_fill_with_defaults(state); > + if (ret) > + goto out; > + } > + > for (i = 0; i < arg->count_objs; i++) { > uint32_t obj_id, count_props; > struct drm_mode_object *obj; > > if (get_user(obj_id, objs_ptr + copied_objs)) { > diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c > index 0dbf04d4aa9e..f13bb7c490c4 100644 > --- a/drivers/gpu/drm/drm_ioctl.c > +++ b/drivers/gpu/drm/drm_ioctl.c > @@ -303,10 +303,13 @@ static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_ > break; > case DRM_CAP_ATOMIC_ASYNC_PAGE_FLIP: > req->value = drm_core_check_feature(dev, DRIVER_ATOMIC) && > dev->mode_config.async_page_flip; > break; > + case DRM_CAP_ATOMIC_RESET: > + req->value = drm_atomic_can_create_state(dev); > + break; > default: > return -EINVAL; > } > return 0; > } > diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h > index bc7ef7684099..b6e2f2edd122 100644 > --- a/include/uapi/drm/drm.h > +++ b/include/uapi/drm/drm.h > @@ -793,10 +793,20 @@ struct drm_gem_change_handle { > * If set to 1, the driver supports &DRM_MODE_PAGE_FLIP_ASYNC for atomic > * commits. > */ > #define DRM_CAP_ATOMIC_ASYNC_PAGE_FLIP 0x15 > > +/** > + * DRM_CAP_ATOMIC_RESET > + * > + * If set to 1, the driver supports the &DRM_MODE_ATOMIC_RESET flag in > + * &DRM_IOCTL_MODE_ATOMIC commits. When supported, userspace can pass that > + * flag to reset all KMS object states to their defaults before applying > + * property changes. > + */ > +#define DRM_CAP_ATOMIC_RESET 0x16 > + > /* DRM_IOCTL_GET_CAP ioctl argument type */ > struct drm_get_cap { > __u64 capability; > __u64 value; > }; > diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h > index ed1a660a3dfd..32eb3f650d7a 100644 > --- a/include/uapi/drm/drm_mode.h > +++ b/include/uapi/drm/drm_mode.h > @@ -1326,10 +1326,21 @@ struct drm_mode_destroy_dumb { > * To the best of the driver's knowledge, visual artifacts are guaranteed to > * not appear when this flag is not set. Some sinks might display visual > * artifacts outside of the driver's control. > */ > #define DRM_MODE_ATOMIC_ALLOW_MODESET 0x0400 > +/** > + * DRM_MODE_ATOMIC_RESET > + * > + * Reset all KMS object states (CRTCs, planes, connectors, color operations) > + * to their default values before applying the properties in this commit. > + * Properties not explicitly included in the commit will remain at their > + * defaults (CRTCs inactive, planes disabled, connectors unbound, etc.). > + * > + * This flag cannot be combined with &DRM_MODE_PAGE_FLIP_ASYNC. > + */ > +#define DRM_MODE_ATOMIC_RESET 0x0800 > > /** > * DRM_MODE_ATOMIC_FLAGS > * > * Bitfield of flags accepted by the &DRM_IOCTL_MODE_ATOMIC IOCTL in > @@ -1338,11 +1349,12 @@ struct drm_mode_destroy_dumb { > #define DRM_MODE_ATOMIC_FLAGS (\ > DRM_MODE_PAGE_FLIP_EVENT |\ > DRM_MODE_PAGE_FLIP_ASYNC |\ > DRM_MODE_ATOMIC_TEST_ONLY |\ > DRM_MODE_ATOMIC_NONBLOCK |\ > - DRM_MODE_ATOMIC_ALLOW_MODESET) > + DRM_MODE_ATOMIC_ALLOW_MODESET |\ > + DRM_MODE_ATOMIC_RESET) > > struct drm_mode_atomic { > __u32 flags; > __u32 count_objs; > __u64 objs_ptr; > -- -- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com GF: Jochen Jaser, Andrew McDonald, (HRB 36809, AG Nürnberg)