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/drm_modes.h>
  10 #include <drm/ttm/ttm_bo_api.h>
  11 #include <drm/ttm/ttm_bo_driver.h>
  12 #include <drm/ttm/ttm_placement.h>
  13
  14 #include <linux/kernel.h> /* for container_of() */
  15
  16 struct drm_mode_create_dumb;
  17 struct drm_plane;
  18 struct drm_plane_state;
  19 struct drm_simple_display_pipe;
  20 struct filp;
  21 struct vm_area_struct;
  22
  23 #define DRM_GEM_VRAM_PL_FLAG_VRAM       TTM_PL_FLAG_VRAM
  24 #define DRM_GEM_VRAM_PL_FLAG_SYSTEM     TTM_PL_FLAG_SYSTEM
  25 #define DRM_GEM_VRAM_PL_FLAG_TOPDOWN    TTM_PL_FLAG_TOPDOWN
  26
  27 /*
  28  * Buffer-object helpers
  29  */
  30
  31 /**
  32  * struct drm_gem_vram_object - GEM object backed by VRAM
  33  * @gem:        GEM object
  34  * @bo:         TTM buffer object
  35  * @kmap:       Mapping information for @bo
  36  * @placement:  TTM placement information. Supported placements are \
  37         %TTM_PL_VRAM and %TTM_PL_SYSTEM
  38  * @placements: TTM placement information.
  39  * @pin_count:  Pin counter
  40  *
  41  * The type struct drm_gem_vram_object represents a GEM object that is
  42  * backed by VRAM. It can be used for simple framebuffer devices with
  43  * dedicated memory. The buffer object can be evicted to system memory if
  44  * video memory becomes scarce.
  45  *
  46  * GEM VRAM objects perform reference counting for pin and mapping
  47  * operations. So a buffer object that has been pinned N times with
  48  * drm_gem_vram_pin() must be unpinned N times with
  49  * drm_gem_vram_unpin(). The same applies to pairs of
  50  * drm_gem_vram_kmap() and drm_gem_vram_kunmap(), as well as pairs of
  51  * drm_gem_vram_vmap() and drm_gem_vram_vunmap().
  52  */
  53 struct drm_gem_vram_object {
  54         struct ttm_buffer_object bo;
  55         struct ttm_bo_kmap_obj kmap;
  56
  57         /**
  58          * @kmap_use_count:
  59          *
  60          * Reference count on the virtual address.
  61          * The address are un-mapped when the count reaches zero.
  62          */
  63         unsigned int kmap_use_count;
  64
  65         /* Supported placements are %TTM_PL_VRAM and %TTM_PL_SYSTEM */
  66         struct ttm_placement placement;
  67         struct ttm_place placements[2];
  68
  69         int pin_count;
  70 };
  71
  72 /**
  73  * Returns the container of type &struct drm_gem_vram_object
  74  * for field bo.
  75  * @bo:         the VRAM buffer object
  76  * Returns:     The containing GEM VRAM object
  77  */
  78 static inline struct drm_gem_vram_object *drm_gem_vram_of_bo(
  79         struct ttm_buffer_object *bo)
  80 {
  81         return container_of(bo, struct drm_gem_vram_object, bo);
  82 }
  83
  84 /**
  85  * Returns the container of type &struct drm_gem_vram_object
  86  * for field gem.
  87  * @gem:        the GEM object
  88  * Returns:     The containing GEM VRAM object
  89  */
  90 static inline struct drm_gem_vram_object *drm_gem_vram_of_gem(
  91         struct drm_gem_object *gem)
  92 {
  93         return container_of(gem, struct drm_gem_vram_object, bo.base);
  94 }
  95
  96 struct drm_gem_vram_object *drm_gem_vram_create(struct drm_device *dev,
  97                                                 size_t size,
  98                                                 unsigned long pg_align);
  99 void drm_gem_vram_put(struct drm_gem_vram_object *gbo);
 100 u64 drm_gem_vram_mmap_offset(struct drm_gem_vram_object *gbo);
 101 s64 drm_gem_vram_offset(struct drm_gem_vram_object *gbo);
 102 int drm_gem_vram_pin(struct drm_gem_vram_object *gbo, unsigned long pl_flag);
 103 int drm_gem_vram_unpin(struct drm_gem_vram_object *gbo);
 104 void *drm_gem_vram_kmap(struct drm_gem_vram_object *gbo, bool map,
 105                         bool *is_iomem);
 106 void drm_gem_vram_kunmap(struct drm_gem_vram_object *gbo);
 107 void *drm_gem_vram_vmap(struct drm_gem_vram_object *gbo);
 108 void drm_gem_vram_vunmap(struct drm_gem_vram_object *gbo, void *vaddr);
 109
 110 int drm_gem_vram_fill_create_dumb(struct drm_file *file,
 111                                   struct drm_device *dev,
 112                                   unsigned long pg_align,
 113                                   unsigned long pitch_align,
 114                                   struct drm_mode_create_dumb *args);
 115
 116 /*
 117  * Helpers for struct drm_driver
 118  */
 119
 120 int drm_gem_vram_driver_dumb_create(struct drm_file *file,
 121                                     struct drm_device *dev,
 122                                     struct drm_mode_create_dumb *args);
 123 int drm_gem_vram_driver_dumb_mmap_offset(struct drm_file *file,
 124                                          struct drm_device *dev,
 125                                          uint32_t handle, uint64_t *offset);
 126
 127 /*
 128  * Helpers for struct drm_plane_helper_funcs
 129  */
 130 int
 131 drm_gem_vram_plane_helper_prepare_fb(struct drm_plane *plane,
 132                                      struct drm_plane_state *new_state);
 133 void
 134 drm_gem_vram_plane_helper_cleanup_fb(struct drm_plane *plane,
 135                                      struct drm_plane_state *old_state);
 136
 137 /*
 138  * Helpers for struct drm_simple_display_pipe_funcs
 139  */
 140
 141 int drm_gem_vram_simple_display_pipe_prepare_fb(
 142         struct drm_simple_display_pipe *pipe,
 143         struct drm_plane_state *new_state);
 144
 145 void drm_gem_vram_simple_display_pipe_cleanup_fb(
 146         struct drm_simple_display_pipe *pipe,
 147         struct drm_plane_state *old_state);
 148
 149 /**
 150  * define DRM_GEM_VRAM_DRIVER - default callback functions for \
 151         &struct drm_driver
 152  *
 153  * Drivers that use VRAM MM and GEM VRAM can use this macro to initialize
 154  * &struct drm_driver with default functions.
 155  */
 156 #define DRM_GEM_VRAM_DRIVER \
 157         .debugfs_init             = drm_vram_mm_debugfs_init, \
 158         .dumb_create              = drm_gem_vram_driver_dumb_create, \
 159         .dumb_map_offset          = drm_gem_vram_driver_dumb_mmap_offset, \
 160         .gem_prime_mmap           = drm_gem_prime_mmap
 161
 162 /*
 163  *  VRAM memory manager
 164  */
 165
 166 /**
 167  * struct drm_vram_mm - An instance of VRAM MM
 168  * @vram_base:  Base address of the managed video memory
 169  * @vram_size:  Size of the managed video memory in bytes
 170  * @bdev:       The TTM BO device.
 171  * @funcs:      TTM BO functions
 172  *
 173  * The fields &struct drm_vram_mm.vram_base and
 174  * &struct drm_vram_mm.vrm_size are managed by VRAM MM, but are
 175  * available for public read access. Use the field
 176  * &struct drm_vram_mm.bdev to access the TTM BO device.
 177  */
 178 struct drm_vram_mm {
 179         uint64_t vram_base;
 180         size_t vram_size;
 181
 182         struct ttm_bo_device bdev;
 183 };
 184
 185 /**
 186  * drm_vram_mm_of_bdev() - \
 187         Returns the container of type &struct ttm_bo_device for field bdev.
 188  * @bdev:       the TTM BO device
 189  *
 190  * Returns:
 191  * The containing instance of &struct drm_vram_mm
 192  */
 193 static inline struct drm_vram_mm *drm_vram_mm_of_bdev(
 194         struct ttm_bo_device *bdev)
 195 {
 196         return container_of(bdev, struct drm_vram_mm, bdev);
 197 }
 198
 199 int drm_vram_mm_debugfs_init(struct drm_minor *minor);
 200
 201 /*
 202  * Helpers for integration with struct drm_device
 203  */
 204
 205 struct drm_vram_mm *drm_vram_helper_alloc_mm(
 206         struct drm_device *dev, uint64_t vram_base, size_t vram_size);
 207 void drm_vram_helper_release_mm(struct drm_device *dev);
 208
 209 /*
 210  * Mode-config helpers
 211  */
 212
 213 enum drm_mode_status
 214 drm_vram_helper_mode_valid(struct drm_device *dev,
 215                            const struct drm_display_mode *mode);
 216
 217 #endif