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FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; TAGGED_RCPT(0.00)[]; DKIM_TRACE(0.00)[suse.de:+]; R_RATELIMIT(0.00)[to_ip_from(RL7gneoo7ydcsn9o76mxr5d8pb)]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:dkim,suse.de:mid,suse.com:url,imap1.dmz-prg2.suse.org:helo,imap1.dmz-prg2.suse.org:rdns] X-Rspamd-Queue-Id: 242EC5BD95 X-Spam-Flag: NO X-Spam-Score: -3.01 X-Spam-Level: Hi Am 20.03.26 um 17:27 schrieb Maxime Ripard: > Commit 47b5ac7daa46 ("drm/atomic: Add new atomic_create_state callback > to drm_private_obj") introduced a new pattern for allocating drm object > states. > > Instead of relying on the reset() callback, it created a new > atomic_create_state hook. This is helpful because reset is a bit > overloaded: it's used to create the initial software state, reset it, > but also reset the hardware. > > It can also be used either at probe time, to create the initial state > and possibly reset the hardware to an expected default, but also during > suspend/resume. > > Both these cases come with different expectations too: during the > initialization, we want to initialize all states, but during > suspend/resume, drm_private_states for example are expected to be kept > around. > > And reset() isn't fallible, which makes it harder to handle > initialization errors properly. > > And this is only really relevant for some drivers, since all the helpers > for reset only create a new state, and don't touch the hardware at all. > > It was thus decided to create a new hook that would allocate and > initialize a pristine state without any side effect: > atomic_create_state to untangle a bit some of it, and to separate the > initialization with the actual reset one might need during a > suspend/resume. > > Let's continue the transition to the new pattern with planes. > > Signed-off-by: Maxime Ripard > --- > drivers/gpu/drm/drm_atomic_state_helper.c | 44 +++++++++++++++++++++++++++++++ > drivers/gpu/drm/drm_mode_config.c | 21 ++++++++++++++- > include/drm/drm_atomic_state_helper.h | 4 +++ > include/drm/drm_plane.h | 13 +++++++++ > 4 files changed, 81 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/drm_atomic_state_helper.c b/drivers/gpu/drm/drm_atomic_state_helper.c > index 2548d6da13675f63304dc92423c5d225de0447a8..f4ce9d3573cbecf216904db54335e0cf84a01c39 100644 > --- a/drivers/gpu/drm/drm_atomic_state_helper.c > +++ b/drivers/gpu/drm/drm_atomic_state_helper.c > @@ -319,10 +319,29 @@ void __drm_atomic_helper_plane_reset(struct drm_plane *plane, > > plane->state = plane_state; > } > EXPORT_SYMBOL(__drm_atomic_helper_plane_reset); > > +/** > + * __drm_atomic_helper_plane_create_state - initializes plane state > + * @plane: plane object > + * @state: new state to initialize > + * > + * Initializes the newly allocated @state, usually required when > + * initializing the drivers. > + * > + * @state is assumed to be zeroed. > + * > + * This is useful for drivers that subclass @drm_plane_state. > + */ > +void __drm_atomic_helper_plane_create_state(struct drm_plane *plane, > + struct drm_plane_state *state) > +{ > + __drm_atomic_helper_plane_state_init(state, plane); > +} > +EXPORT_SYMBOL(__drm_atomic_helper_plane_create_state); Will this function have another purpuse?  Could we just call _plane_state_init() directly from anywhere? Best regards Thomas > + > /** > * drm_atomic_helper_plane_reset - default &drm_plane_funcs.reset hook for planes > * @plane: drm plane > * > * Resets the atomic state for @plane by freeing the state pointer (which might > @@ -338,10 +357,35 @@ void drm_atomic_helper_plane_reset(struct drm_plane *plane) > if (plane->state) > __drm_atomic_helper_plane_reset(plane, plane->state); > } > EXPORT_SYMBOL(drm_atomic_helper_plane_reset); > > +/** > + * drm_atomic_helper_plane_create_state - default &drm_plane_funcs.atomic_create_state hook for planes > + * @plane: plane object > + * > + * Initializes a pristine @drm_plane_state. > + * > + * This is useful for drivers that don't subclass @drm_plane_state. > + * > + * RETURNS: > + * Pointer to new plane state, or ERR_PTR on failure. > + */ > +struct drm_plane_state *drm_atomic_helper_plane_create_state(struct drm_plane *plane) > +{ > + struct drm_plane_state *state; > + > + state = kzalloc_obj(*state); > + if (!state) > + return ERR_PTR(-ENOMEM); > + > + __drm_atomic_helper_plane_create_state(plane, state); > + > + return state; > +} > +EXPORT_SYMBOL(drm_atomic_helper_plane_create_state); > + > /** > * __drm_atomic_helper_plane_duplicate_state - copy atomic plane state > * @plane: plane object > * @state: atomic plane state > * > diff --git a/drivers/gpu/drm/drm_mode_config.c b/drivers/gpu/drm/drm_mode_config.c > index cba527571ca66d3aa6dc652c87e03a19815d1d41..09b8292195ba5eb5d96735aee5506407bd32ade3 100644 > --- a/drivers/gpu/drm/drm_mode_config.c > +++ b/drivers/gpu/drm/drm_mode_config.c > @@ -180,10 +180,26 @@ int drm_mode_getresources(struct drm_device *dev, void *data, > drm_connector_list_iter_end(&conn_iter); > > return ret; > } > > +static int drm_mode_config_plane_create_state(struct drm_plane *plane) > +{ > + struct drm_plane_state *plane_state; > + > + if (!plane->funcs->atomic_create_state) > + return 0; > + > + plane_state = plane->funcs->atomic_create_state(plane); > + if (IS_ERR(plane_state)) > + return PTR_ERR(plane_state); > + > + plane->state = plane_state; > + > + return 0; > +} > + > /** > * drm_mode_config_reset - call ->reset callbacks > * @dev: drm device > * > * This functions calls all the crtc's, encoder's and connector's ->reset > @@ -204,13 +220,16 @@ void drm_mode_config_reset(struct drm_device *dev) > struct drm_connector_list_iter conn_iter; > > drm_for_each_colorop(colorop, dev) > drm_colorop_reset(colorop); > > - drm_for_each_plane(plane, dev) > + drm_for_each_plane(plane, dev) { > if (plane->funcs->reset) > plane->funcs->reset(plane); > + else if (plane->funcs->atomic_create_state) > + drm_mode_config_plane_create_state(plane); > + } > > drm_for_each_crtc(crtc, dev) > if (crtc->funcs->reset) > crtc->funcs->reset(crtc); > > diff --git a/include/drm/drm_atomic_state_helper.h b/include/drm/drm_atomic_state_helper.h > index 44e8850aae7fd6390f4b58188a9c677b8389702f..6a3a2feb3dff1f2fbdf2a6e63d8d7317c7d6ead6 100644 > --- a/include/drm/drm_atomic_state_helper.h > +++ b/include/drm/drm_atomic_state_helper.h > @@ -53,10 +53,14 @@ void __drm_atomic_helper_crtc_destroy_state(struct drm_crtc_state *state); > void drm_atomic_helper_crtc_destroy_state(struct drm_crtc *crtc, > struct drm_crtc_state *state); > > void __drm_atomic_helper_plane_state_init(struct drm_plane_state *state, > struct drm_plane *plane); > +void __drm_atomic_helper_plane_create_state(struct drm_plane *plane, > + struct drm_plane_state *state); > +struct drm_plane_state * > +drm_atomic_helper_plane_create_state(struct drm_plane *plane); > void __drm_atomic_helper_plane_reset(struct drm_plane *plane, > struct drm_plane_state *state); > void drm_atomic_helper_plane_reset(struct drm_plane *plane); > void __drm_atomic_helper_plane_duplicate_state(struct drm_plane *plane, > struct drm_plane_state *state); > diff --git a/include/drm/drm_plane.h b/include/drm/drm_plane.h > index 703ef4d1bbbcf084c43aa5e127d28691878061c4..4d4d511b681d50c17fbc593cce9f706d63e04a52 100644 > --- a/include/drm/drm_plane.h > +++ b/include/drm/drm_plane.h > @@ -386,10 +386,23 @@ struct drm_plane_funcs { > * 0 on success or a negative error code on failure. > */ > int (*set_property)(struct drm_plane *plane, > struct drm_property *property, uint64_t val); > > + /** > + * @atomic_create_state: > + * > + * Allocates a pristine, initialized, state for the plane object > + * and returns it. > + * > + * RETURNS: > + * > + * A new, pristine, plane state instance or an error pointer > + * on failure. > + */ > + struct drm_plane_state *(*atomic_create_state)(struct drm_plane *plane); > + > /** > * @atomic_duplicate_state: > * > * Duplicate the current atomic state for this plane and return it. > * The core and helpers guarantee that any atomic state duplicated with > -- -- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com GF: Jochen Jaser, Andrew McDonald, Werner Knoblich, (HRB 36809, AG Nürnberg)