1/* SPDX-License-Identifier: MIT */ 2/* 3 * Copyright © 2016 Intel Corporation 4 * 5 * Permission is hereby granted, free of charge, to any person obtaining a 6 * copy of this software and associated documentation files (the "Software"), 7 * to deal in the Software without restriction, including without limitation 8 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 9 * and/or sell copies of the Software, and to permit persons to whom the 10 * Software is furnished to do so, subject to the following conditions: 11 * 12 * The above copyright notice and this permission notice (including the next 13 * paragraph) shall be included in all copies or substantial portions of the 14 * Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 22 * IN THE SOFTWARE. 23 * 24 */ 25 26#ifndef __I915_VMA_TYPES_H__ 27#define __I915_VMA_TYPES_H__ 28 29#include <linux/rbtree.h> 30 31#include <drm/drm_mm.h> 32 33#include "gem/i915_gem_object_types.h" 34 35enum i915_cache_level; 36 37/** 38 * DOC: Global GTT views 39 * 40 * Background and previous state 41 * 42 * Historically objects could exists (be bound) in global GTT space only as 43 * singular instances with a view representing all of the object's backing pages 44 * in a linear fashion. This view will be called a normal view. 45 * 46 * To support multiple views of the same object, where the number of mapped 47 * pages is not equal to the backing store, or where the layout of the pages 48 * is not linear, concept of a GGTT view was added. 49 * 50 * One example of an alternative view is a stereo display driven by a single 51 * image. In this case we would have a framebuffer looking like this 52 * (2x2 pages): 53 * 54 * 12 55 * 34 56 * 57 * Above would represent a normal GGTT view as normally mapped for GPU or CPU 58 * rendering. In contrast, fed to the display engine would be an alternative 59 * view which could look something like this: 60 * 61 * 1212 62 * 3434 63 * 64 * In this example both the size and layout of pages in the alternative view is 65 * different from the normal view. 66 * 67 * Implementation and usage 68 * 69 * GGTT views are implemented using VMAs and are distinguished via enum 70 * i915_ggtt_view_type and struct i915_ggtt_view. 71 * 72 * A new flavour of core GEM functions which work with GGTT bound objects were 73 * added with the _ggtt_ infix, and sometimes with _view postfix to avoid 74 * renaming in large amounts of code. They take the struct i915_ggtt_view 75 * parameter encapsulating all metadata required to implement a view. 76 * 77 * As a helper for callers which are only interested in the normal view, 78 * globally const i915_ggtt_view_normal singleton instance exists. All old core 79 * GEM API functions, the ones not taking the view parameter, are operating on, 80 * or with the normal GGTT view. 81 * 82 * Code wanting to add or use a new GGTT view needs to: 83 * 84 * 1. Add a new enum with a suitable name. 85 * 2. Extend the metadata in the i915_ggtt_view structure if required. 86 * 3. Add support to i915_get_vma_pages(). 87 * 88 * New views are required to build a scatter-gather table from within the 89 * i915_get_vma_pages function. This table is stored in the vma.ggtt_view and 90 * exists for the lifetime of an VMA. 91 * 92 * Core API is designed to have copy semantics which means that passed in 93 * struct i915_ggtt_view does not need to be persistent (left around after 94 * calling the core API functions). 95 * 96 */ 97 98struct intel_remapped_plane_info { 99 /* in gtt pages */ 100 u32 offset; 101 u16 width; 102 u16 height; 103 u16 src_stride; 104 u16 dst_stride; 105} __packed; 106 107struct intel_remapped_info { 108 struct intel_remapped_plane_info plane[2]; 109 u32 unused_mbz; 110} __packed; 111 112struct intel_rotation_info { 113 struct intel_remapped_plane_info plane[2]; 114} __packed; 115 116struct intel_partial_info { 117 u64 offset; 118 unsigned int size; 119} __packed; 120 121enum i915_ggtt_view_type { 122 I915_GGTT_VIEW_NORMAL = 0, 123 I915_GGTT_VIEW_ROTATED = sizeof(struct intel_rotation_info), 124 I915_GGTT_VIEW_PARTIAL = sizeof(struct intel_partial_info), 125 I915_GGTT_VIEW_REMAPPED = sizeof(struct intel_remapped_info), 126}; 127 128static inline void assert_i915_gem_gtt_types(void) 129{ 130 BUILD_BUG_ON(sizeof(struct intel_rotation_info) != 2 * sizeof(u32) + 8 * sizeof(u16)); 131 BUILD_BUG_ON(sizeof(struct intel_partial_info) != sizeof(u64) + sizeof(unsigned int)); 132 BUILD_BUG_ON(sizeof(struct intel_remapped_info) != 3 * sizeof(u32) + 8 * sizeof(u16)); 133 134 /* Check that rotation/remapped shares offsets for simplicity */ 135 BUILD_BUG_ON(offsetof(struct intel_remapped_info, plane[0]) != 136 offsetof(struct intel_rotation_info, plane[0])); 137 BUILD_BUG_ON(offsetofend(struct intel_remapped_info, plane[1]) != 138 offsetofend(struct intel_rotation_info, plane[1])); 139 140 /* As we encode the size of each branch inside the union into its type, 141 * we have to be careful that each branch has a unique size. 142 */ 143 switch ((enum i915_ggtt_view_type)0) { 144 case I915_GGTT_VIEW_NORMAL: 145 case I915_GGTT_VIEW_PARTIAL: 146 case I915_GGTT_VIEW_ROTATED: 147 case I915_GGTT_VIEW_REMAPPED: 148 /* gcc complains if these are identical cases */ 149 break; 150 } 151} 152 153struct i915_ggtt_view { 154 enum i915_ggtt_view_type type; 155 union { 156 /* Members need to contain no holes/padding */ 157 struct intel_partial_info partial; 158 struct intel_rotation_info rotated; 159 struct intel_remapped_info remapped; 160 }; 161}; 162 163/** 164 * DOC: Virtual Memory Address 165 * 166 * A VMA represents a GEM BO that is bound into an address space. Therefore, a 167 * VMA's presence cannot be guaranteed before binding, or after unbinding the 168 * object into/from the address space. 169 * 170 * To make things as simple as possible (ie. no refcounting), a VMA's lifetime 171 * will always be <= an objects lifetime. So object refcounting should cover us. 172 */ 173struct i915_vma { 174 struct drm_mm_node node; 175 176 struct i915_address_space *vm; 177 const struct i915_vma_ops *ops; 178 179 struct drm_i915_gem_object *obj; 180 struct dma_resv *resv; /** Alias of obj->resv */ 181 182 struct sg_table *pages; 183 void __iomem *iomap; 184 void *private; /* owned by creator */ 185 186 struct i915_fence_reg *fence; 187 188 u64 size; 189 u64 display_alignment; 190 struct i915_page_sizes page_sizes; 191 192 /* mmap-offset associated with fencing for this vma */ 193 struct i915_mmap_offset *mmo; 194 195 u32 fence_size; 196 u32 fence_alignment; 197 198 /** 199 * Count of the number of times this vma has been opened by different 200 * handles (but same file) for execbuf, i.e. the number of aliases 201 * that exist in the ctx->handle_vmas LUT for this vma. 202 */ 203 struct kref ref; 204 atomic_t open_count; 205 atomic_t flags; 206 /** 207 * How many users have pinned this object in GTT space. 208 * 209 * This is a tightly bound, fairly small number of users, so we 210 * stuff inside the flags field so that we can both check for overflow 211 * and detect a no-op i915_vma_pin() in a single check, while also 212 * pinning the vma. 213 * 214 * The worst case display setup would have the same vma pinned for 215 * use on each plane on each crtc, while also building the next atomic 216 * state and holding a pin for the length of the cleanup queue. In the 217 * future, the flip queue may be increased from 1. 218 * Estimated worst case: 3 [qlen] * 4 [max crtcs] * 7 [max planes] = 84 219 * 220 * For GEM, the number of concurrent users for pwrite/pread is 221 * unbounded. For execbuffer, it is currently one but will in future 222 * be extended to allow multiple clients to pin vma concurrently. 223 * 224 * We also use suballocated pages, with each suballocation claiming 225 * its own pin on the shared vma. At present, this is limited to 226 * exclusive cachelines of a single page, so a maximum of 64 possible 227 * users. 228 */ 229#define I915_VMA_PIN_MASK 0x3ff 230#define I915_VMA_OVERFLOW 0x200 231 232 /** Flags and address space this VMA is bound to */ 233#define I915_VMA_GLOBAL_BIND_BIT 10 234#define I915_VMA_LOCAL_BIND_BIT 11 235 236#define I915_VMA_GLOBAL_BIND ((int)BIT(I915_VMA_GLOBAL_BIND_BIT)) 237#define I915_VMA_LOCAL_BIND ((int)BIT(I915_VMA_LOCAL_BIND_BIT)) 238 239#define I915_VMA_BIND_MASK (I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND) 240 241#define I915_VMA_ALLOC_BIT 12 242 243#define I915_VMA_ERROR_BIT 13 244#define I915_VMA_ERROR ((int)BIT(I915_VMA_ERROR_BIT)) 245 246#define I915_VMA_GGTT_BIT 14 247#define I915_VMA_CAN_FENCE_BIT 15 248#define I915_VMA_USERFAULT_BIT 16 249#define I915_VMA_GGTT_WRITE_BIT 17 250 251#define I915_VMA_GGTT ((int)BIT(I915_VMA_GGTT_BIT)) 252#define I915_VMA_CAN_FENCE ((int)BIT(I915_VMA_CAN_FENCE_BIT)) 253#define I915_VMA_USERFAULT ((int)BIT(I915_VMA_USERFAULT_BIT)) 254#define I915_VMA_GGTT_WRITE ((int)BIT(I915_VMA_GGTT_WRITE_BIT)) 255 256#define I915_VMA_SCANOUT_BIT 18 257#define I915_VMA_SCANOUT ((int)BIT(I915_VMA_SCANOUT_BIT)) 258 259 struct i915_active active; 260 261#define I915_VMA_PAGES_BIAS 24 262#define I915_VMA_PAGES_ACTIVE (BIT(24) | 1) 263 atomic_t pages_count; /* number of active binds to the pages */ 264 struct mutex pages_mutex; /* protect acquire/release of backing pages */ 265 266 /** 267 * Support different GGTT views into the same object. 268 * This means there can be multiple VMA mappings per object and per VM. 269 * i915_ggtt_view_type is used to distinguish between those entries. 270 * The default one of zero (I915_GGTT_VIEW_NORMAL) is default and also 271 * assumed in GEM functions which take no ggtt view parameter. 272 */ 273 struct i915_ggtt_view ggtt_view; 274 275 /** This object's place on the active/inactive lists */ 276 struct list_head vm_link; 277 278 struct list_head obj_link; /* Link in the object's VMA list */ 279 struct rb_node obj_node; 280 struct hlist_node obj_hash; 281 282 /** This vma's place in the eviction list */ 283 struct list_head evict_link; 284 285 struct list_head closed_link; 286}; 287 288#endif 289