include/drm/drm_gem_vram_helper.h

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2
   3 #ifndef DRM_GEM_VRAM_HELPER_H
   4 #define DRM_GEM_VRAM_HELPER_H
   5
   6 #include <drm/drm_file.h>
   7 #include <drm/drm_gem.h>
   8 #include <drm/drm_ioctl.h>
   9 #include <drm/ttm/ttm_bo_api.h>
  10 #include <drm/ttm/ttm_bo_driver.h>
  11 #include <drm/ttm/ttm_placement.h>
  12
  13 #include <linux/kernel.h> /* for container_of() */
  14
  15 struct drm_mode_create_dumb;
  16 struct drm_plane;
  17 struct drm_plane_state;
  18 struct drm_simple_display_pipe;
  19 struct filp;
  20 struct vm_area_struct;
  21
  22 #define DRM_GEM_VRAM_PL_FLAG_VRAM       TTM_PL_FLAG_VRAM
  23 #define DRM_GEM_VRAM_PL_FLAG_SYSTEM     TTM_PL_FLAG_SYSTEM
  24 #define DRM_GEM_VRAM_PL_FLAG_TOPDOWN    TTM_PL_FLAG_TOPDOWN
  25
  26 /*
  27  * Buffer-object helpers
  28  */
  29
  30 /**
  31  * struct drm_gem_vram_object - GEM object backed by VRAM
  32  * @gem:        GEM object
  33  * @bo:         TTM buffer object
  34  * @kmap:       Mapping information for @bo
  35  * @placement:  TTM placement information. Supported placements are \
  36         %TTM_PL_VRAM and %TTM_PL_SYSTEM
  37  * @placements: TTM placement information.
  38  * @pin_count:  Pin counter
  39  *
  40  * The type struct drm_gem_vram_object represents a GEM object that is
  41  * backed by VRAM. It can be used for simple framebuffer devices with
  42  * dedicated memory. The buffer object can be evicted to system memory if
  43  * video memory becomes scarce.
  44  *
  45  * GEM VRAM objects perform reference counting for pin and mapping
  46  * operations. So a buffer object that has been pinned N times with
  47  * drm_gem_vram_pin() must be unpinned N times with
  48  * drm_gem_vram_unpin(). The same applies to pairs of
  49  * drm_gem_vram_kmap() and drm_gem_vram_kunmap(), as well as pairs of
  50  * drm_gem_vram_vmap() and drm_gem_vram_vunmap().
  51  */
  52 struct drm_gem_vram_object {
  53         struct ttm_buffer_object bo;
  54         struct ttm_bo_kmap_obj kmap;
  55
  56         /**
  57          * @kmap_use_count:
  58          *
  59          * Reference count on the virtual address.
  60          * The address are un-mapped when the count reaches zero.
  61          */
  62         unsigned int kmap_use_count;
  63
  64         /* Supported placements are %TTM_PL_VRAM and %TTM_PL_SYSTEM */
  65         struct ttm_placement placement;
  66         struct ttm_place placements[2];
  67
  68         int pin_count;
  69 };
  70
  71 /**
  72  * Returns the container of type &struct drm_gem_vram_object
  73  * for field bo.
  74  * @bo:         the VRAM buffer object
  75  * Returns:     The containing GEM VRAM object
  76  */
  77 static inline struct drm_gem_vram_object *drm_gem_vram_of_bo(
  78         struct ttm_buffer_object *bo)
  79 {
  80         return container_of(bo, struct drm_gem_vram_object, bo);
  81 }
  82
  83 /**
  84  * Returns the container of type &struct drm_gem_vram_object
  85  * for field gem.
  86  * @gem:        the GEM object
  87  * Returns:     The containing GEM VRAM object
  88  */
  89 static inline struct drm_gem_vram_object *drm_gem_vram_of_gem(
  90         struct drm_gem_object *gem)
  91 {
  92         return container_of(gem, struct drm_gem_vram_object, bo.base);
  93 }
  94
  95 struct drm_gem_vram_object *drm_gem_vram_create(struct drm_device *dev,
  96                                                 size_t size,
  97                                                 unsigned long pg_align);
  98 void drm_gem_vram_put(struct drm_gem_vram_object *gbo);
  99 u64 drm_gem_vram_mmap_offset(struct drm_gem_vram_object *gbo);
 100 s64 drm_gem_vram_offset(struct drm_gem_vram_object *gbo);
 101 int drm_gem_vram_pin(struct drm_gem_vram_object *gbo, unsigned long pl_flag);
 102 int drm_gem_vram_unpin(struct drm_gem_vram_object *gbo);
 103 void *drm_gem_vram_kmap(struct drm_gem_vram_object *gbo, bool map,
 104                         bool *is_iomem);
 105 void drm_gem_vram_kunmap(struct drm_gem_vram_object *gbo);
 106 void *drm_gem_vram_vmap(struct drm_gem_vram_object *gbo);
 107 void drm_gem_vram_vunmap(struct drm_gem_vram_object *gbo, void *vaddr);
 108
 109 int drm_gem_vram_fill_create_dumb(struct drm_file *file,
 110                                   struct drm_device *dev,
 111                                   unsigned long pg_align,
 112                                   unsigned long pitch_align,
 113                                   struct drm_mode_create_dumb *args);
 114
 115 /*
 116  * Helpers for struct drm_driver
 117  */
 118
 119 int drm_gem_vram_driver_dumb_create(struct drm_file *file,
 120                                     struct drm_device *dev,
 121                                     struct drm_mode_create_dumb *args);
 122 int drm_gem_vram_driver_dumb_mmap_offset(struct drm_file *file,
 123                                          struct drm_device *dev,
 124                                          uint32_t handle, uint64_t *offset);
 125
 126 /*
 127  * Helpers for struct drm_plane_helper_funcs
 128  */
 129 int
 130 drm_gem_vram_plane_helper_prepare_fb(struct drm_plane *plane,
 131                                      struct drm_plane_state *new_state);
 132 void
 133 drm_gem_vram_plane_helper_cleanup_fb(struct drm_plane *plane,
 134                                      struct drm_plane_state *old_state);
 135
 136 /*
 137  * Helpers for struct drm_simple_display_pipe_funcs
 138  */
 139
 140 int drm_gem_vram_simple_display_pipe_prepare_fb(
 141         struct drm_simple_display_pipe *pipe,
 142         struct drm_plane_state *new_state);
 143
 144 void drm_gem_vram_simple_display_pipe_cleanup_fb(
 145         struct drm_simple_display_pipe *pipe,
 146         struct drm_plane_state *old_state);
 147
 148 /**
 149  * define DRM_GEM_VRAM_DRIVER - default callback functions for \
 150         &struct drm_driver
 151  *
 152  * Drivers that use VRAM MM and GEM VRAM can use this macro to initialize
 153  * &struct drm_driver with default functions.
 154  */
 155 #define DRM_GEM_VRAM_DRIVER \
 156         .debugfs_init             = drm_vram_mm_debugfs_init, \
 157         .dumb_create              = drm_gem_vram_driver_dumb_create, \
 158         .dumb_map_offset          = drm_gem_vram_driver_dumb_mmap_offset, \
 159         .gem_prime_mmap           = drm_gem_prime_mmap
 160
 161 /*
 162  *  VRAM memory manager
 163  */
 164
 165 /**
 166  * struct drm_vram_mm - An instance of VRAM MM
 167  * @vram_base:  Base address of the managed video memory
 168  * @vram_size:  Size of the managed video memory in bytes
 169  * @bdev:       The TTM BO device.
 170  * @funcs:      TTM BO functions
 171  *
 172  * The fields &struct drm_vram_mm.vram_base and
 173  * &struct drm_vram_mm.vrm_size are managed by VRAM MM, but are
 174  * available for public read access. Use the field
 175  * &struct drm_vram_mm.bdev to access the TTM BO device.
 176  */
 177 struct drm_vram_mm {
 178         uint64_t vram_base;
 179         size_t vram_size;
 180
 181         struct ttm_bo_device bdev;
 182 };
 183
 184 /**
 185  * drm_vram_mm_of_bdev() - \
 186         Returns the container of type &struct ttm_bo_device for field bdev.
 187  * @bdev:       the TTM BO device
 188  *
 189  * Returns:
 190  * The containing instance of &struct drm_vram_mm
 191  */
 192 static inline struct drm_vram_mm *drm_vram_mm_of_bdev(
 193         struct ttm_bo_device *bdev)
 194 {
 195         return container_of(bdev, struct drm_vram_mm, bdev);
 196 }
 197
 198 int drm_vram_mm_debugfs_init(struct drm_minor *minor);
 199
 200 /*
 201  * Helpers for integration with struct drm_device
 202  */
 203
 204 struct drm_vram_mm *drm_vram_helper_alloc_mm(
 205         struct drm_device *dev, uint64_t vram_base, size_t vram_size);
 206 void drm_vram_helper_release_mm(struct drm_device *dev);
 207
 208 #endif