linux_kernel/include/drm/drm_mode_config.h

/*
 * Copyright (c) 2016 Intel Corporation
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that copyright
 * notice and this permission notice appear in supporting documentation, and
 * that the name of the copyright holders not be used in advertising or
 * publicity pertaining to distribution of the software without specific,
 * written prior permission.  The copyright holders make no representations
 * about the suitability of this software for any purpose.  It is provided "as
 * is" without express or implied warranty.
 *
 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
 * OF THIS SOFTWARE.
 */

#ifndef __DRM_MODE_CONFIG_H__
#define __DRM_MODE_CONFIG_H__

#include <linux/mutex.h>
#include <linux/types.h>
#include <linux/idr.h>
#include <linux/workqueue.h>

#include <drm/drm_modeset_lock.h>

struct drm_file;
struct drm_device;
struct drm_atomic_state;
struct drm_mode_fb_cmd2;

/**
 * struct drm_mode_config_funcs - basic driver provided mode setting functions
 *
 * Some global (i.e. not per-CRTC, connector, etc) mode setting functions that
 * involve drivers.
 */
struct drm_mode_config_funcs {
	/**
	 * @fb_create:
	 *
	 * Create a new framebuffer object. The core does basic checks on the
	 * requested metadata, but most of that is left to the driver. See
	 * &struct drm_mode_fb_cmd2 for details.
	 *
	 * If the parameters are deemed valid and the backing storage objects in
	 * the underlying memory manager all exist, then the driver allocates
	 * a new &drm_framebuffer structure, subclassed to contain
	 * driver-specific information (like the internal native buffer object
	 * references). It also needs to fill out all relevant metadata, which
	 * should be done by calling drm_helper_mode_fill_fb_struct().
	 *
	 * The initialization is finalized by calling drm_framebuffer_init(),
	 * which registers the framebuffer and makes it accessible to other
	 * threads.
	 *
	 * RETURNS:
	 *
	 * A new framebuffer with an initial reference count of 1 or a negative
	 * error code encoded with ERR_PTR().
	 */
	struct drm_framebuffer *(*fb_create)(struct drm_device *dev,
					     struct drm_file *file_priv,
					     const struct drm_mode_fb_cmd2 *mode_cmd);

	/**
	 * @output_poll_changed:
	 *
	 * Callback used by helpers to inform the driver of output configuration
	 * changes.
	 *
	 * Drivers implementing fbdev emulation with the helpers can call
	 * drm_fb_helper_hotplug_changed from this hook to inform the fbdev
	 * helper of output changes.
	 *
	 * FIXME:
	 *
	 * Except that there's no vtable for device-level helper callbacks
	 * there's no reason this is a core function.
	 */
	void (*output_poll_changed)(struct drm_device *dev);

	/**
	 * @atomic_check:
	 *
	 * This is the only hook to validate an atomic modeset update. This
	 * function must reject any modeset and state changes which the hardware
	 * or driver doesn't support. This includes but is of course not limited
	 * to:
	 *
	 *  - Checking that the modes, framebuffers, scaling and placement
	 *    requirements and so on are within the limits of the hardware.
	 *
	 *  - Checking that any hidden shared resources are not oversubscribed.
	 *    This can be shared PLLs, shared lanes, overall memory bandwidth,
	 *    display fifo space (where shared between planes or maybe even
	 *    CRTCs).
	 *
	 *  - Checking that virtualized resources exported to userspace are not
	 *    oversubscribed. For various reasons it can make sense to expose
	 *    more planes, crtcs or encoders than which are physically there. One
	 *    example is dual-pipe operations (which generally should be hidden
	 *    from userspace if when lockstepped in hardware, exposed otherwise),
	 *    where a plane might need 1 hardware plane (if it's just on one
	 *    pipe), 2 hardware planes (when it spans both pipes) or maybe even
	 *    shared a hardware plane with a 2nd plane (if there's a compatible
	 *    plane requested on the area handled by the other pipe).
	 *
	 *  - Check that any transitional state is possible and that if
	 *    requested, the update can indeed be done in the vblank period
	 *    without temporarily disabling some functions.
	 *
	 *  - Check any other constraints the driver or hardware might have.
	 *
	 *  - This callback also needs to correctly fill out the &drm_crtc_state
	 *    in this update to make sure that drm_atomic_crtc_needs_modeset()
	 *    reflects the nature of the possible update and returns true if and
	 *    only if the update cannot be applied without tearing within one
	 *    vblank on that CRTC. The core uses that information to reject
	 *    updates which require a full modeset (i.e. blanking the screen, or
	 *    at least pausing updates for a substantial amount of time) if
	 *    userspace has disallowed that in its request.
	 *
	 *  - The driver also does not need to repeat basic input validation
	 *    like done for the corresponding legacy entry points. The core does
	 *    that before calling this hook.
	 *
	 * See the documentation of @atomic_commit for an exhaustive list of
	 * error conditions which don't have to be checked at the
	 * ->atomic_check() stage?
	 *
	 * See the documentation for &struct drm_atomic_state for how exactly
	 * an atomic modeset update is described.
	 *
	 * Drivers using the atomic helpers can implement this hook using
	 * drm_atomic_helper_check(), or one of the exported sub-functions of
	 * it.
	 *
	 * RETURNS:
	 *
	 * 0 on success or one of the below negative error codes:
	 *
	 *  - -EINVAL, if any of the above constraints are violated.
	 *
	 *  - -EDEADLK, when returned from an attempt to acquire an additional
	 *    &drm_modeset_lock through drm_modeset_lock().
	 *
	 *  - -ENOMEM, if allocating additional state sub-structures failed due
	 *    to lack of memory.
	 *
	 *  - -EINTR, -EAGAIN or -ERESTARTSYS, if the IOCTL should be restarted.
	 *    This can either be due to a pending signal, or because the driver
	 *    needs to completely bail out to recover from an exceptional
	 *    situation like a GPU hang. From a userspace point all errors are
	 *    treated equally.
	 */
	int (*atomic_check)(struct drm_device *dev,
			    struct drm_atomic_state *state);

	/**
	 * @atomic_commit:
	 *
	 * This is the only hook to commit an atomic modeset update. The core
	 * guarantees that @atomic_check has been called successfully before
	 * calling this function, and that nothing has been changed in the
	 * interim.
	 *
	 * See the documentation for &struct drm_atomic_state for how exactly
	 * an atomic modeset update is described.
	 *
	 * Drivers using the atomic helpers can implement this hook using
	 * drm_atomic_helper_commit(), or one of the exported sub-functions of
	 * it.
	 *
	 * Nonblocking commits (as indicated with the nonblock parameter) must
	 * do any preparatory work which might result in an unsuccessful commit
	 * in the context of this callback. The only exceptions are hardware
	 * errors resulting in -EIO. But even in that case the driver must
	 * ensure that the display pipe is at least running, to avoid
	 * compositors crashing when pageflips don't work. Anything else,
	 * specifically committing the update to the hardware, should be done
	 * without blocking the caller. For updates which do not require a
	 * modeset this must be guaranteed.
	 *
	 * The driver must wait for any pending rendering to the new
	 * framebuffers to complete before executing the flip. It should also
	 * wait for any pending rendering from other drivers if the underlying
	 * buffer is a shared dma-buf. Nonblocking commits must not wait for
	 * rendering in the context of this callback.
	 *
	 * An application can request to be notified when the atomic commit has
	 * completed. These events are per-CRTC and can be distinguished by the
	 * CRTC index supplied in &drm_event to userspace.
	 *
	 * The drm core will supply a &struct drm_event in the event
	 * member of each CRTC's &drm_crtc_state structure. See the
	 * documentation for &drm_crtc_state for more details about the precise
	 * semantics of this event.
	 *
	 * NOTE:
	 *
	 * Drivers are not allowed to shut down any display pipe successfully
	 * enabled through an atomic commit on their own. Doing so can result in
	 * compositors crashing if a page flip is suddenly rejected because the
	 * pipe is off.
	 *
	 * RETURNS:
	 *
	 * 0 on success or one of the below negative error codes:
	 *
	 *  - -EBUSY, if a nonblocking updated is requested and there is
	 *    an earlier updated pending. Drivers are allowed to support a queue
	 *    of outstanding updates, but currently no driver supports that.
	 *    Note that drivers must wait for preceding updates to complete if a
	 *    synchronous update is requested, they are not allowed to fail the
	 *    commit in that case.
	 *
	 *  - -ENOMEM, if the driver failed to allocate memory. Specifically
	 *    this can happen when trying to pin framebuffers, which must only
	 *    be done when committing the state.
	 *
	 *  - -ENOSPC, as a refinement of the more generic -ENOMEM to indicate
	 *    that the driver has run out of vram, iommu space or similar GPU
	 *    address space needed for framebuffer.
	 *
	 *  - -EIO, if the hardware completely died.
	 *
	 *  - -EINTR, -EAGAIN or -ERESTARTSYS, if the IOCTL should be restarted.
	 *    This can either be due to a pending signal, or because the driver
	 *    needs to completely bail out to recover from an exceptional
	 *    situation like a GPU hang. From a userspace point of view all errors are
	 *    treated equally.
	 *
	 * This list is exhaustive. Specifically this hook is not allowed to
	 * return -EINVAL (any invalid requests should be caught in
	 * @atomic_check) or -EDEADLK (this function must not acquire
	 * additional modeset locks).
	 */
	int (*atomic_commit)(struct drm_device *dev,
			     struct drm_atomic_state *state,
			     bool nonblock);

	/**
	 * @atomic_state_alloc:
	 *
	 * This optional hook can be used by drivers that want to subclass struct
	 * &drm_atomic_state to be able to track their own driver-private global
	 * state easily. If this hook is implemented, drivers must also
	 * implement @atomic_state_clear and @atomic_state_free.
	 *
	 * RETURNS:
	 *
	 * A new &drm_atomic_state on success or NULL on failure.
	 */
	struct drm_atomic_state *(*atomic_state_alloc)(struct drm_device *dev);

	/**
	 * @atomic_state_clear:
	 *
	 * This hook must clear any driver private state duplicated into the
	 * passed-in &drm_atomic_state. This hook is called when the caller
	 * encountered a &drm_modeset_lock deadlock and needs to drop all
	 * already acquired locks as part of the deadlock avoidance dance
	 * implemented in drm_modeset_lock_backoff().
	 *
	 * Any duplicated state must be invalidated since a concurrent atomic
	 * update might change it, and the drm atomic interfaces always apply
	 * updates as relative changes to the current state.
	 *
	 * Drivers that implement this must call drm_atomic_state_default_clear()
	 * to clear common state.
	 */
	void (*atomic_state_clear)(struct drm_atomic_state *state);

	/**
	 * @atomic_state_free:
	 *
	 * This hook needs driver private resources and the &drm_atomic_state
	 * itself. Note that the core first calls drm_atomic_state_clear() to
	 * avoid code duplicate between the clear and free hooks.
	 *
	 * Drivers that implement this must call drm_atomic_state_default_free()
	 * to release common resources.
	 */
	void (*atomic_state_free)(struct drm_atomic_state *state);
};

/**
 * struct drm_mode_config - Mode configuration control structure
 * @mutex: mutex protecting KMS related lists and structures
 * @connection_mutex: ww mutex protecting connector state and routing
 * @acquire_ctx: global implicit acquire context used by atomic drivers for
 * 	legacy IOCTLs
 * @fb_lock: mutex to protect fb state and lists
 * @num_fb: number of fbs available
 * @fb_list: list of framebuffers available
 * @num_encoder: number of encoders on this device
 * @encoder_list: list of encoder objects
 * @num_overlay_plane: number of overlay planes on this device
 * @num_total_plane: number of universal (i.e. with primary/curso) planes on this device
 * @plane_list: list of plane objects
 * @num_crtc: number of CRTCs on this device
 * @crtc_list: list of CRTC objects
 * @property_list: list of property objects
 * @min_width: minimum pixel width on this device
 * @min_height: minimum pixel height on this device
 * @max_width: maximum pixel width on this device
 * @max_height: maximum pixel height on this device
 * @funcs: core driver provided mode setting functions
 * @fb_base: base address of the framebuffer
 * @poll_enabled: track polling support for this device
 * @poll_running: track polling status for this device
 * @delayed_event: track delayed poll uevent deliver for this device
 * @output_poll_work: delayed work for polling in process context
 * @property_blob_list: list of all the blob property objects
 * @blob_lock: mutex for blob property allocation and management
 * @*_property: core property tracking
 * @preferred_depth: preferred RBG pixel depth, used by fb helpers
 * @prefer_shadow: hint to userspace to prefer shadow-fb rendering
 * @cursor_width: hint to userspace for max cursor width
 * @cursor_height: hint to userspace for max cursor height
 * @helper_private: mid-layer private data
 *
 * Core mode resource tracking structure.  All CRTC, encoders, and connectors
 * enumerated by the driver are added here, as are global properties.  Some
 * global restrictions are also here, e.g. dimension restrictions.
 */
struct drm_mode_config {
	struct mutex mutex; /* protects configuration (mode lists etc.) */
	struct drm_modeset_lock connection_mutex; /* protects connector->encoder and encoder->crtc links */
	struct drm_modeset_acquire_ctx *acquire_ctx; /* for legacy _lock_all() / _unlock_all() */

	/**
	 * @idr_mutex:
	 *
	 * Mutex for KMS ID allocation and management. Protects both @crtc_idr
	 * and @tile_idr.
	 */
	struct mutex idr_mutex;

	/**
	 * @crtc_idr:
	 *
	 * Main KMS ID tracking object. Use this idr for all IDs, fb, crtc,
	 * connector, modes - just makes life easier to have only one.
	 */
	struct idr crtc_idr;

	/**
	 * @tile_idr:
	 *
	 * Use this idr for allocating new IDs for tiled sinks like use in some
	 * high-res DP MST screens.
	 */
	struct idr tile_idr;

	struct mutex fb_lock; /* proctects global and per-file fb lists */
	int num_fb;
	struct list_head fb_list;

	/**
	 * @connector_list_lock: Protects @num_connector and
	 * @connector_list.
	 */
	spinlock_t connector_list_lock;
	/**
	 * @num_connector: Number of connectors on this device. Protected by
	 * @connector_list_lock.
	 */
	int num_connector;
	/**
	 * @connector_ida: ID allocator for connector indices.
	 */
	struct ida connector_ida;
	/**
	 * @connector_list: List of connector objects. Protected by
	 * @connector_list_lock. Only use drm_for_each_connector_iter() and
	 * &struct drm_connector_list_iter to walk this list.
	 */
	struct list_head connector_list;
	int num_encoder;
	struct list_head encoder_list;

	/*
	 * Track # of overlay planes separately from # of total planes.  By
	 * default we only advertise overlay planes to userspace; if userspace
	 * sets the "universal plane" capability bit, we'll go ahead and
	 * expose all planes.
	 */
	int num_overlay_plane;
	int num_total_plane;
	struct list_head plane_list;

	int num_crtc;
	struct list_head crtc_list;

	struct list_head property_list;

	int min_width, min_height;
	int max_width, max_height;
	const struct drm_mode_config_funcs *funcs;
	resource_size_t fb_base;

	/* output poll support */
	bool poll_enabled;
	bool poll_running;
	bool delayed_event;
	struct delayed_work output_poll_work;

	struct mutex blob_lock;

	/* pointers to standard properties */
	struct list_head property_blob_list;
	/**
	 * @edid_property: Default connector property to hold the EDID of the
	 * currently connected sink, if any.
	 */
	struct drm_property *edid_property;
	/**
	 * @dpms_property: Default connector property to control the
	 * connector's DPMS state.
	 */
	struct drm_property *dpms_property;
	/**
	 * @path_property: Default connector property to hold the DP MST path
	 * for the port.
	 */
	struct drm_property *path_property;
	/**
	 * @tile_property: Default connector property to store the tile
	 * position of a tiled screen, for sinks which need to be driven with
	 * multiple CRTCs.
	 */
	struct drm_property *tile_property;
	/**
	 * @plane_type_property: Default plane property to differentiate
	 * CURSOR, PRIMARY and OVERLAY legacy uses of planes.
	 */
	struct drm_property *plane_type_property;
	/**
	 * @prop_src_x: Default atomic plane property for the plane source
	 * position in the connected &drm_framebuffer.
	 */
	struct drm_property *prop_src_x;
	/**
	 * @prop_src_y: Default atomic plane property for the plane source
	 * position in the connected &drm_framebuffer.
	 */
	struct drm_property *prop_src_y;
	/**
	 * @prop_src_w: Default atomic plane property for the plane source
	 * position in the connected &drm_framebuffer.
	 */
	struct drm_property *prop_src_w;
	/**
	 * @prop_src_h: Default atomic plane property for the plane source
	 * position in the connected &drm_framebuffer.
	 */
	struct drm_property *prop_src_h;
	/**
	 * @prop_crtc_x: Default atomic plane property for the plane destination
	 * position in the &drm_crtc is is being shown on.
	 */
	struct drm_property *prop_crtc_x;
	/**
	 * @prop_crtc_y: Default atomic plane property for the plane destination
	 * position in the &drm_crtc is is being shown on.
	 */
	struct drm_property *prop_crtc_y;
	/**
	 * @prop_crtc_w: Default atomic plane property for the plane destination
	 * position in the &drm_crtc is is being shown on.
	 */
	struct drm_property *prop_crtc_w;
	/**
	 * @prop_crtc_h: Default atomic plane property for the plane destination
	 * position in the &drm_crtc is is being shown on.
	 */
	struct drm_property *prop_crtc_h;
	/**
	 * @prop_fb_id: Default atomic plane property to specify the
	 * &drm_framebuffer.
	 */
	struct drm_property *prop_fb_id;
	/**
	 * @prop_in_fence_fd: Sync File fd representing the incoming fences
	 * for a Plane.
	 */
	struct drm_property *prop_in_fence_fd;
	/**
	 * @prop_out_fence_ptr: Sync File fd pointer representing the
	 * outgoing fences for a CRTC. Userspace should provide a pointer to a
	 * value of type s64, and then cast that pointer to u64.
	 */
	struct drm_property *prop_out_fence_ptr;
	/**
	 * @prop_crtc_id: Default atomic plane property to specify the
	 * &drm_crtc.
	 */
	struct drm_property *prop_crtc_id;
	/**
	 * @prop_active: Default atomic CRTC property to control the active
	 * state, which is the simplified implementation for DPMS in atomic
	 * drivers.
	 */
	struct drm_property *prop_active;
	/**
	 * @prop_mode_id: Default atomic CRTC property to set the mode for a
	 * CRTC. A 0 mode implies that the CRTC is entirely disabled - all
	 * connectors must be of and active must be set to disabled, too.
	 */
	struct drm_property *prop_mode_id;

	/**
	 * @dvi_i_subconnector_property: Optional DVI-I property to
	 * differentiate between analog or digital mode.
	 */
	struct drm_property *dvi_i_subconnector_property;
	/**
	 * @dvi_i_select_subconnector_property: Optional DVI-I property to
	 * select between analog or digital mode.
	 */
	struct drm_property *dvi_i_select_subconnector_property;

	/**
	 * @tv_subconnector_property: Optional TV property to differentiate
	 * between different TV connector types.
	 */
	struct drm_property *tv_subconnector_property;
	/**
	 * @tv_select_subconnector_property: Optional TV property to select
	 * between different TV connector types.
	 */
	struct drm_property *tv_select_subconnector_property;
	/**
	 * @tv_mode_property: Optional TV property to select
	 * the output TV mode.
	 */
	struct drm_property *tv_mode_property;
	/**
	 * @tv_left_margin_property: Optional TV property to set the left
	 * margin.
	 */
	struct drm_property *tv_left_margin_property;
	/**
	 * @tv_right_margin_property: Optional TV property to set the right
	 * margin.
	 */
	struct drm_property *tv_right_margin_property;
	/**
	 * @tv_top_margin_property: Optional TV property to set the right
	 * margin.
	 */
	struct drm_property *tv_top_margin_property;
	/**
	 * @tv_bottom_margin_property: Optional TV property to set the right
	 * margin.
	 */
	struct drm_property *tv_bottom_margin_property;
	/**
	 * @tv_brightness_property: Optional TV property to set the
	 * brightness.
	 */
	struct drm_property *tv_brightness_property;
	/**
	 * @tv_contrast_property: Optional TV property to set the
	 * contrast.
	 */
	struct drm_property *tv_contrast_property;
	/**
	 * @tv_flicker_reduction_property: Optional TV property to control the
	 * flicker reduction mode.
	 */
	struct drm_property *tv_flicker_reduction_property;
	/**
	 * @tv_overscan_property: Optional TV property to control the overscan
	 * setting.
	 */
	struct drm_property *tv_overscan_property;
	/**
	 * @tv_saturation_property: Optional TV property to set the
	 * saturation.
	 */
	struct drm_property *tv_saturation_property;
	/**
	 * @tv_hue_property: Optional TV property to set the hue.
	 */
	struct drm_property *tv_hue_property;

	/**
	 * @scaling_mode_property: Optional connector property to control the
	 * upscaling, mostly used for built-in panels.
	 */
	struct drm_property *scaling_mode_property;
	/**
	 * @aspect_ratio_property: Optional connector property to control the
	 * HDMI infoframe aspect ratio setting.
	 */
	struct drm_property *aspect_ratio_property;
	/**
	 * @degamma_lut_property: Optional CRTC property to set the LUT used to
	 * convert the framebuffer's colors to linear gamma.
	 */
	struct drm_property *degamma_lut_property;
	/**
	 * @degamma_lut_size_property: Optional CRTC property for the size of
	 * the degamma LUT as supported by the driver (read-only).
	 */
	struct drm_property *degamma_lut_size_property;
	/**
	 * @ctm_property: Optional CRTC property to set the
	 * matrix used to convert colors after the lookup in the
	 * degamma LUT.
	 */
	struct drm_property *ctm_property;
	/**
	 * @gamma_lut_property: Optional CRTC property to set the LUT used to
	 * convert the colors, after the CTM matrix, to the gamma space of the
	 * connected screen.
	 */
	struct drm_property *gamma_lut_property;
	/**
	 * @gamma_lut_size_property: Optional CRTC property for the size of the
	 * gamma LUT as supported by the driver (read-only).
	 */
	struct drm_property *gamma_lut_size_property;

	/**
	 * @suggested_x_property: Optional connector property with a hint for
	 * the position of the output on the host's screen.
	 */
	struct drm_property *suggested_x_property;
	/**
	 * @suggested_y_property: Optional connector property with a hint for
	 * the position of the output on the host's screen.
	 */
	struct drm_property *suggested_y_property;

	/* dumb ioctl parameters */
	uint32_t preferred_depth, prefer_shadow;

	/**
	 * @async_page_flip: Does this device support async flips on the primary
	 * plane?
	 */
	bool async_page_flip;

	/**
	 * @allow_fb_modifiers:
	 *
	 * Whether the driver supports fb modifiers in the ADDFB2.1 ioctl call.
	 */
	bool allow_fb_modifiers;

	/* cursor size */
	uint32_t cursor_width, cursor_height;

	struct drm_mode_config_helper_funcs *helper_private;
};

void drm_mode_config_init(struct drm_device *dev);
void drm_mode_config_reset(struct drm_device *dev);
void drm_mode_config_cleanup(struct drm_device *dev);

#endif