root/include/drm/drm_drv.h
/*
 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
 * Copyright (c) 2009-2010, Code Aurora Forum.
 * Copyright 2016 Intel Corp.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

#ifndef _DRM_DRV_H_
#define _DRM_DRV_H_

#include <linux/list.h>
#include <linux/irqreturn.h>

#include <video/nomodeset.h>

#include <drm/drm_device.h>

struct dmem_cgroup_region;
struct drm_fb_helper;
struct drm_fb_helper_surface_size;
struct drm_file;
struct drm_gem_object;
struct drm_master;
struct drm_minor;
struct dma_buf;
struct dma_buf_attachment;
struct drm_display_mode;
struct drm_mode_create_dumb;
struct drm_printer;
struct sg_table;

/**
 * enum drm_driver_feature - feature flags
 *
 * See &drm_driver.driver_features, drm_device.driver_features and
 * drm_core_check_feature().
 */
enum drm_driver_feature {
        /**
         * @DRIVER_GEM:
         *
         * Driver use the GEM memory manager. This should be set for all modern
         * drivers.
         */
        DRIVER_GEM                      = BIT(0),
        /**
         * @DRIVER_MODESET:
         *
         * Driver supports mode setting interfaces (KMS).
         */
        DRIVER_MODESET                  = BIT(1),
        /**
         * @DRIVER_RENDER:
         *
         * Driver supports dedicated render nodes. See also the :ref:`section on
         * render nodes <drm_render_node>` for details.
         */
        DRIVER_RENDER                   = BIT(3),
        /**
         * @DRIVER_ATOMIC:
         *
         * Driver supports the full atomic modesetting userspace API. Drivers
         * which only use atomic internally, but do not support the full
         * userspace API (e.g. not all properties converted to atomic, or
         * multi-plane updates are not guaranteed to be tear-free) should not
         * set this flag.
         */
        DRIVER_ATOMIC                   = BIT(4),
        /**
         * @DRIVER_SYNCOBJ:
         *
         * Driver supports &drm_syncobj for explicit synchronization of command
         * submission.
         */
        DRIVER_SYNCOBJ                  = BIT(5),
        /**
         * @DRIVER_SYNCOBJ_TIMELINE:
         *
         * Driver supports the timeline flavor of &drm_syncobj for explicit
         * synchronization of command submission.
         */
        DRIVER_SYNCOBJ_TIMELINE         = BIT(6),
        /**
         * @DRIVER_COMPUTE_ACCEL:
         *
         * Driver supports compute acceleration devices. This flag is mutually exclusive with
         * @DRIVER_RENDER and @DRIVER_MODESET. Devices that support both graphics and compute
         * acceleration should be handled by two drivers that are connected using auxiliary bus.
         */
        DRIVER_COMPUTE_ACCEL            = BIT(7),
        /**
         * @DRIVER_GEM_GPUVA:
         *
         * Driver supports user defined GPU VA bindings for GEM objects.
         */
        DRIVER_GEM_GPUVA                = BIT(8),
        /**
         * @DRIVER_CURSOR_HOTSPOT:
         *
         * Driver supports and requires cursor hotspot information in the
         * cursor plane (e.g. cursor plane has to actually track the mouse
         * cursor and the clients are required to set hotspot in order for
         * the cursor planes to work correctly).
         */
        DRIVER_CURSOR_HOTSPOT           = BIT(9),

        /* IMPORTANT: Below are all the legacy flags, add new ones above. */

        /**
         * @DRIVER_USE_AGP:
         *
         * Set up DRM AGP support, see drm_agp_init(), the DRM core will manage
         * AGP resources. New drivers don't need this.
         */
        DRIVER_USE_AGP                  = BIT(25),
        /**
         * @DRIVER_LEGACY:
         *
         * Denote a legacy driver using shadow attach. Do not use.
         */
        DRIVER_LEGACY                   = BIT(26),
        /**
         * @DRIVER_PCI_DMA:
         *
         * Driver is capable of PCI DMA, mapping of PCI DMA buffers to userspace
         * will be enabled. Only for legacy drivers. Do not use.
         */
        DRIVER_PCI_DMA                  = BIT(27),
        /**
         * @DRIVER_SG:
         *
         * Driver can perform scatter/gather DMA, allocation and mapping of
         * scatter/gather buffers will be enabled. Only for legacy drivers. Do
         * not use.
         */
        DRIVER_SG                       = BIT(28),

        /**
         * @DRIVER_HAVE_DMA:
         *
         * Driver supports DMA, the userspace DMA API will be supported. Only
         * for legacy drivers. Do not use.
         */
        DRIVER_HAVE_DMA                 = BIT(29),
        /**
         * @DRIVER_HAVE_IRQ:
         *
         * Legacy irq support. Only for legacy drivers. Do not use.
         */
        DRIVER_HAVE_IRQ                 = BIT(30),
};

/**
 * struct drm_driver - DRM driver structure
 *
 * This structure represent the common code for a family of cards. There will be
 * one &struct drm_device for each card present in this family. It contains lots
 * of vfunc entries, and a pile of those probably should be moved to more
 * appropriate places like &drm_mode_config_funcs or into a new operations
 * structure for GEM drivers.
 */
struct drm_driver {
        /**
         * @load:
         *
         * Backward-compatible driver callback to complete initialization steps
         * after the driver is registered.  For this reason, may suffer from
         * race conditions and its use is deprecated for new drivers.  It is
         * therefore only supported for existing drivers not yet converted to
         * the new scheme.  See devm_drm_dev_alloc() and drm_dev_register() for
         * proper and race-free way to set up a &struct drm_device.
         *
         * This is deprecated, do not use!
         *
         * Returns:
         *
         * Zero on success, non-zero value on failure.
         */
        int (*load) (struct drm_device *, unsigned long flags);

        /**
         * @open:
         *
         * Driver callback when a new &struct drm_file is opened. Useful for
         * setting up driver-private data structures like buffer allocators,
         * execution contexts or similar things. Such driver-private resources
         * must be released again in @postclose.
         *
         * Since the display/modeset side of DRM can only be owned by exactly
         * one &struct drm_file (see &drm_file.is_master and &drm_device.master)
         * there should never be a need to set up any modeset related resources
         * in this callback. Doing so would be a driver design bug.
         *
         * Returns:
         *
         * 0 on success, a negative error code on failure, which will be
         * promoted to userspace as the result of the open() system call.
         */
        int (*open) (struct drm_device *, struct drm_file *);

        /**
         * @postclose:
         *
         * One of the driver callbacks when a new &struct drm_file is closed.
         * Useful for tearing down driver-private data structures allocated in
         * @open like buffer allocators, execution contexts or similar things.
         *
         * Since the display/modeset side of DRM can only be owned by exactly
         * one &struct drm_file (see &drm_file.is_master and &drm_device.master)
         * there should never be a need to tear down any modeset related
         * resources in this callback. Doing so would be a driver design bug.
         */
        void (*postclose) (struct drm_device *, struct drm_file *);

        /**
         * @unload:
         *
         * Reverse the effects of the driver load callback.  Ideally,
         * the clean up performed by the driver should happen in the
         * reverse order of the initialization.  Similarly to the load
         * hook, this handler is deprecated and its usage should be
         * dropped in favor of an open-coded teardown function at the
         * driver layer.  See drm_dev_unregister() and drm_dev_put()
         * for the proper way to remove a &struct drm_device.
         *
         * The unload() hook is called right after unregistering
         * the device.
         *
         */
        void (*unload) (struct drm_device *);

        /**
         * @release:
         *
         * Optional callback for destroying device data after the final
         * reference is released, i.e. the device is being destroyed.
         *
         * This is deprecated, clean up all memory allocations associated with a
         * &drm_device using drmm_add_action(), drmm_kmalloc() and related
         * managed resources functions.
         */
        void (*release) (struct drm_device *);

        /**
         * @master_set:
         *
         * Called whenever the minor master is set. Only used by vmwgfx.
         */
        void (*master_set)(struct drm_device *dev, struct drm_file *file_priv,
                           bool from_open);
        /**
         * @master_drop:
         *
         * Called whenever the minor master is dropped. Only used by vmwgfx.
         */
        void (*master_drop)(struct drm_device *dev, struct drm_file *file_priv);

        /**
         * @debugfs_init:
         *
         * Allows drivers to create driver-specific debugfs files.
         */
        void (*debugfs_init)(struct drm_minor *minor);

        /**
         * @gem_create_object: constructor for gem objects
         *
         * Hook for allocating the GEM object struct, for use by the CMA
         * and SHMEM GEM helpers. Returns a GEM object on success, or an
         * ERR_PTR()-encoded error code otherwise.
         */
        struct drm_gem_object *(*gem_create_object)(struct drm_device *dev,
                                                    size_t size);

        /**
         * @prime_handle_to_fd:
         *
         * PRIME export function. Only used by vmwgfx.
         */
        int (*prime_handle_to_fd)(struct drm_device *dev, struct drm_file *file_priv,
                                uint32_t handle, uint32_t flags, int *prime_fd);
        /**
         * @prime_fd_to_handle:
         *
         * PRIME import function. Only used by vmwgfx.
         */
        int (*prime_fd_to_handle)(struct drm_device *dev, struct drm_file *file_priv,
                                int prime_fd, uint32_t *handle);

        /**
         * @gem_prime_import:
         *
         * Import hook for GEM drivers.
         *
         * This defaults to drm_gem_prime_import() if not set.
         */
        struct drm_gem_object * (*gem_prime_import)(struct drm_device *dev,
                                struct dma_buf *dma_buf);
        /**
         * @gem_prime_import_sg_table:
         *
         * Optional hook used by the PRIME helper functions
         * drm_gem_prime_import() respectively drm_gem_prime_import_dev().
         */
        struct drm_gem_object *(*gem_prime_import_sg_table)(
                                struct drm_device *dev,
                                struct dma_buf_attachment *attach,
                                struct sg_table *sgt);

        /**
         * @dumb_create:
         *
         * This creates a new dumb buffer in the driver's backing storage manager (GEM,
         * TTM or something else entirely) and returns the resulting buffer handle. This
         * handle can then be wrapped up into a framebuffer modeset object.
         *
         * Note that userspace is not allowed to use such objects for render
         * acceleration - drivers must create their own private ioctls for such a use
         * case.
         *
         * Width, height and depth are specified in the &drm_mode_create_dumb
         * argument. The callback needs to fill the handle, pitch and size for
         * the created buffer.
         *
         * Called by the user via ioctl.
         *
         * Returns:
         *
         * Zero on success, negative errno on failure.
         */
        int (*dumb_create)(struct drm_file *file_priv,
                           struct drm_device *dev,
                           struct drm_mode_create_dumb *args);
        /**
         * @dumb_map_offset:
         *
         * Allocate an offset in the drm device node's address space to be able to
         * memory map a dumb buffer.
         *
         * The default implementation is drm_gem_create_mmap_offset(). GEM based
         * drivers must not overwrite this.
         *
         * Called by the user via ioctl.
         *
         * Returns:
         *
         * Zero on success, negative errno on failure.
         */
        int (*dumb_map_offset)(struct drm_file *file_priv,
                               struct drm_device *dev, uint32_t handle,
                               uint64_t *offset);

        /**
         * @fbdev_probe:
         *
         * Allocates and initialize the fb_info structure for fbdev emulation.
         * Furthermore it also needs to allocate the DRM framebuffer used to
         * back the fbdev.
         *
         * This callback is mandatory for fbdev support.
         *
         * Returns:
         *
         * 0 on success ot a negative error code otherwise.
         */
        int (*fbdev_probe)(struct drm_fb_helper *fbdev_helper,
                           struct drm_fb_helper_surface_size *sizes);

        /**
         * @show_fdinfo:
         *
         * Print device specific fdinfo.  See Documentation/gpu/drm-usage-stats.rst.
         */
        void (*show_fdinfo)(struct drm_printer *p, struct drm_file *f);

        /** @major: driver major number */
        int major;
        /** @minor: driver minor number */
        int minor;
        /** @patchlevel: driver patch level */
        int patchlevel;
        /** @name: driver name */
        char *name;
        /** @desc: driver description */
        char *desc;

        /**
         * @driver_features:
         * Driver features, see &enum drm_driver_feature. Drivers can disable
         * some features on a per-instance basis using
         * &drm_device.driver_features.
         */
        u32 driver_features;

        /**
         * @ioctls:
         *
         * Array of driver-private IOCTL description entries. See the chapter on
         * :ref:`IOCTL support in the userland interfaces
         * chapter<drm_driver_ioctl>` for the full details.
         */

        const struct drm_ioctl_desc *ioctls;
        /** @num_ioctls: Number of entries in @ioctls. */
        int num_ioctls;

        /**
         * @fops:
         *
         * File operations for the DRM device node. See the discussion in
         * :ref:`file operations<drm_driver_fops>` for in-depth coverage and
         * some examples.
         */
        const struct file_operations *fops;
};

void *__devm_drm_dev_alloc(struct device *parent,
                           const struct drm_driver *driver,
                           size_t size, size_t offset);

struct dmem_cgroup_region *
drmm_cgroup_register_region(struct drm_device *dev,
                            const char *region_name, u64 size);

/**
 * devm_drm_dev_alloc - Resource managed allocation of a &drm_device instance
 * @parent: Parent device object
 * @driver: DRM driver
 * @type: the type of the struct which contains struct &drm_device
 * @member: the name of the &drm_device within @type.
 *
 * This allocates and initialize a new DRM device. No device registration is done.
 * Call drm_dev_register() to advertice the device to user space and register it
 * with other core subsystems. This should be done last in the device
 * initialization sequence to make sure userspace can't access an inconsistent
 * state.
 *
 * The initial ref-count of the object is 1. Use drm_dev_get() and
 * drm_dev_put() to take and drop further ref-counts.
 *
 * It is recommended that drivers embed &struct drm_device into their own device
 * structure.
 *
 * Note that this manages the lifetime of the resulting &drm_device
 * automatically using devres. The DRM device initialized with this function is
 * automatically put on driver detach using drm_dev_put().
 *
 * RETURNS:
 * Pointer to new DRM device, or ERR_PTR on failure.
 */
#define devm_drm_dev_alloc(parent, driver, type, member) \
        ((type *) __devm_drm_dev_alloc(parent, driver, sizeof(type), \
                                       offsetof(type, member)))

struct drm_device *drm_dev_alloc(const struct drm_driver *driver,
                                 struct device *parent);

void *__drm_dev_alloc(struct device *parent,
                      const struct drm_driver *driver,
                      size_t size, size_t offset);

int drm_dev_register(struct drm_device *dev, unsigned long flags);
void drm_dev_unregister(struct drm_device *dev);

void drm_dev_get(struct drm_device *dev);
void drm_dev_put(struct drm_device *dev);
void drm_put_dev(struct drm_device *dev);
bool drm_dev_enter(struct drm_device *dev, int *idx);
void drm_dev_exit(int idx);
void drm_dev_unplug(struct drm_device *dev);
int drm_dev_wedged_event(struct drm_device *dev, unsigned long method,
                         struct drm_wedge_task_info *info);

/**
 * drm_dev_is_unplugged - is a DRM device unplugged
 * @dev: DRM device
 *
 * This function can be called to check whether a hotpluggable is unplugged.
 * Unplugging itself is singalled through drm_dev_unplug(). If a device is
 * unplugged, these two functions guarantee that any store before calling
 * drm_dev_unplug() is visible to callers of this function after it completes
 *
 * WARNING: This function fundamentally races against drm_dev_unplug(). It is
 * recommended that drivers instead use the underlying drm_dev_enter() and
 * drm_dev_exit() function pairs.
 */
static inline bool drm_dev_is_unplugged(struct drm_device *dev)
{
        int idx;

        if (drm_dev_enter(dev, &idx)) {
                drm_dev_exit(idx);
                return false;
        }

        return true;
}

/**
 * drm_core_check_all_features - check driver feature flags mask
 * @dev: DRM device to check
 * @features: feature flag(s) mask
 *
 * This checks @dev for driver features, see &drm_driver.driver_features,
 * &drm_device.driver_features, and the various &enum drm_driver_feature flags.
 *
 * Returns true if all features in the @features mask are supported, false
 * otherwise.
 */
static inline bool drm_core_check_all_features(const struct drm_device *dev,
                                               u32 features)
{
        u32 supported = dev->driver->driver_features & dev->driver_features;

        return features && (supported & features) == features;
}

/**
 * drm_core_check_feature - check driver feature flags
 * @dev: DRM device to check
 * @feature: feature flag
 *
 * This checks @dev for driver features, see &drm_driver.driver_features,
 * &drm_device.driver_features, and the various &enum drm_driver_feature flags.
 *
 * Returns true if the @feature is supported, false otherwise.
 */
static inline bool drm_core_check_feature(const struct drm_device *dev,
                                          enum drm_driver_feature feature)
{
        return drm_core_check_all_features(dev, feature);
}

/**
 * drm_drv_uses_atomic_modeset - check if the driver implements
 * atomic_commit()
 * @dev: DRM device
 *
 * This check is useful if drivers do not have DRIVER_ATOMIC set but
 * have atomic modesetting internally implemented.
 */
static inline bool drm_drv_uses_atomic_modeset(struct drm_device *dev)
{
        return drm_core_check_feature(dev, DRIVER_ATOMIC) ||
                (dev->mode_config.funcs && dev->mode_config.funcs->atomic_commit != NULL);
}


/* TODO: Inline drm_firmware_drivers_only() in all its callers. */
static inline bool drm_firmware_drivers_only(void)
{
        return video_firmware_drivers_only();
}

#if defined(CONFIG_DEBUG_FS)
void drm_debugfs_dev_init(struct drm_device *dev);
void drm_debugfs_init_root(void);
void drm_debugfs_remove_root(void);
void drm_debugfs_bridge_params(void);
#else
static inline void drm_debugfs_dev_init(struct drm_device *dev)
{
}

static inline void drm_debugfs_init_root(void)
{
}

static inline void drm_debugfs_remove_root(void)
{
}

static inline void drm_debugfs_bridge_params(void)
{
}
#endif

#endif