drivers/gpu/drm/i915/gt/intel_engine_user.c

   1 /*
   2  * SPDX-License-Identifier: MIT
   3  *
   4  * Copyright © 2019 Intel Corporation
   5  */
   6
   7 #include <linux/list.h>
   8 #include <linux/list_sort.h>
   9 #include <linux/llist.h>
  10
  11 #include "i915_drv.h"
  12 #include "intel_engine.h"
  13 #include "intel_engine_user.h"
  14 #include "intel_gt.h"
  15
  16 struct intel_engine_cs *
  17 intel_engine_lookup_user(struct drm_i915_private *i915, u8 class, u8 instance)
  18 {
  19         struct rb_node *p = i915->uabi_engines.rb_node;
  20
  21         while (p) {
  22                 struct intel_engine_cs *it =
  23                         rb_entry(p, typeof(*it), uabi_node);
  24
  25                 if (class < it->uabi_class)
  26                         p = p->rb_left;
  27                 else if (class > it->uabi_class ||
  28                          instance > it->uabi_instance)
  29                         p = p->rb_right;
  30                 else if (instance < it->uabi_instance)
  31                         p = p->rb_left;
  32                 else
  33                         return it;
  34         }
  35
  36         return NULL;
  37 }
  38
  39 void intel_engine_add_user(struct intel_engine_cs *engine)
  40 {
  41         llist_add((struct llist_node *)&engine->uabi_node,
  42                   (struct llist_head *)&engine->i915->uabi_engines);
  43 }
  44
  45 static const u8 uabi_classes[] = {
  46         [RENDER_CLASS] = I915_ENGINE_CLASS_RENDER,
  47         [COPY_ENGINE_CLASS] = I915_ENGINE_CLASS_COPY,
  48         [VIDEO_DECODE_CLASS] = I915_ENGINE_CLASS_VIDEO,
  49         [VIDEO_ENHANCEMENT_CLASS] = I915_ENGINE_CLASS_VIDEO_ENHANCE,
  50 };
  51
  52 static int engine_cmp(void *priv, struct list_head *A, struct list_head *B)
  53 {
  54         const struct intel_engine_cs *a =
  55                 container_of((struct rb_node *)A, typeof(*a), uabi_node);
  56         const struct intel_engine_cs *b =
  57                 container_of((struct rb_node *)B, typeof(*b), uabi_node);
  58
  59         if (uabi_classes[a->class] < uabi_classes[b->class])
  60                 return -1;
  61         if (uabi_classes[a->class] > uabi_classes[b->class])
  62                 return 1;
  63
  64         if (a->instance < b->instance)
  65                 return -1;
  66         if (a->instance > b->instance)
  67                 return 1;
  68
  69         return 0;
  70 }
  71
  72 static struct llist_node *get_engines(struct drm_i915_private *i915)
  73 {
  74         return llist_del_all((struct llist_head *)&i915->uabi_engines);
  75 }
  76
  77 static void sort_engines(struct drm_i915_private *i915,
  78                          struct list_head *engines)
  79 {
  80         struct llist_node *pos, *next;
  81
  82         llist_for_each_safe(pos, next, get_engines(i915)) {
  83                 struct intel_engine_cs *engine =
  84                         container_of((struct rb_node *)pos, typeof(*engine),
  85                                      uabi_node);
  86                 list_add((struct list_head *)&engine->uabi_node, engines);
  87         }
  88         list_sort(NULL, engines, engine_cmp);
  89 }
  90
  91 static void set_scheduler_caps(struct drm_i915_private *i915)
  92 {
  93         static const struct {
  94                 u8 engine;
  95                 u8 sched;
  96         } map[] = {
  97 #define MAP(x, y) { ilog2(I915_ENGINE_##x), ilog2(I915_SCHEDULER_CAP_##y) }
  98                 MAP(HAS_PREEMPTION, PREEMPTION),
  99                 MAP(HAS_SEMAPHORES, SEMAPHORES),
 100                 MAP(SUPPORTS_STATS, ENGINE_BUSY_STATS),
 101 #undef MAP
 102         };
 103         struct intel_engine_cs *engine;
 104         u32 enabled, disabled;
 105
 106         enabled = 0;
 107         disabled = 0;
 108         for_each_uabi_engine(engine, i915) { /* all engines must agree! */
 109                 int i;
 110
 111                 if (engine->schedule)
 112                         enabled |= (I915_SCHEDULER_CAP_ENABLED |
 113                                     I915_SCHEDULER_CAP_PRIORITY);
 114                 else
 115                         disabled |= (I915_SCHEDULER_CAP_ENABLED |
 116                                      I915_SCHEDULER_CAP_PRIORITY);
 117
 118                 for (i = 0; i < ARRAY_SIZE(map); i++) {
 119                         if (engine->flags & BIT(map[i].engine))
 120                                 enabled |= BIT(map[i].sched);
 121                         else
 122                                 disabled |= BIT(map[i].sched);
 123                 }
 124         }
 125
 126         i915->caps.scheduler = enabled & ~disabled;
 127         if (!(i915->caps.scheduler & I915_SCHEDULER_CAP_ENABLED))
 128                 i915->caps.scheduler = 0;
 129 }
 130
 131 const char *intel_engine_class_repr(u8 class)
 132 {
 133         static const char * const uabi_names[] = {
 134                 [RENDER_CLASS] = "rcs",
 135                 [COPY_ENGINE_CLASS] = "bcs",
 136                 [VIDEO_DECODE_CLASS] = "vcs",
 137                 [VIDEO_ENHANCEMENT_CLASS] = "vecs",
 138         };
 139
 140         if (class >= ARRAY_SIZE(uabi_names) || !uabi_names[class])
 141                 return "xxx";
 142
 143         return uabi_names[class];
 144 }
 145
 146 struct legacy_ring {
 147         struct intel_gt *gt;
 148         u8 class;
 149         u8 instance;
 150 };
 151
 152 static int legacy_ring_idx(const struct legacy_ring *ring)
 153 {
 154         static const struct {
 155                 u8 base, max;
 156         } map[] = {
 157                 [RENDER_CLASS] = { RCS0, 1 },
 158                 [COPY_ENGINE_CLASS] = { BCS0, 1 },
 159                 [VIDEO_DECODE_CLASS] = { VCS0, I915_MAX_VCS },
 160                 [VIDEO_ENHANCEMENT_CLASS] = { VECS0, I915_MAX_VECS },
 161         };
 162
 163         if (GEM_DEBUG_WARN_ON(ring->class >= ARRAY_SIZE(map)))
 164                 return INVALID_ENGINE;
 165
 166         if (GEM_DEBUG_WARN_ON(ring->instance >= map[ring->class].max))
 167                 return INVALID_ENGINE;
 168
 169         return map[ring->class].base + ring->instance;
 170 }
 171
 172 static void add_legacy_ring(struct legacy_ring *ring,
 173                             struct intel_engine_cs *engine)
 174 {
 175         if (engine->gt != ring->gt || engine->class != ring->class) {
 176                 ring->gt = engine->gt;
 177                 ring->class = engine->class;
 178                 ring->instance = 0;
 179         }
 180
 181         engine->legacy_idx = legacy_ring_idx(ring);
 182         if (engine->legacy_idx != INVALID_ENGINE)
 183                 ring->instance++;
 184 }
 185
 186 void intel_engines_driver_register(struct drm_i915_private *i915)
 187 {
 188         struct legacy_ring ring = {};
 189         u8 uabi_instances[4] = {};
 190         struct list_head *it, *next;
 191         struct rb_node **p, *prev;
 192         LIST_HEAD(engines);
 193
 194         sort_engines(i915, &engines);
 195
 196         prev = NULL;
 197         p = &i915->uabi_engines.rb_node;
 198         list_for_each_safe(it, next, &engines) {
 199                 struct intel_engine_cs *engine =
 200                         container_of((struct rb_node *)it, typeof(*engine),
 201                                      uabi_node);
 202                 char old[sizeof(engine->name)];
 203
 204                 if (intel_gt_has_unrecoverable_error(engine->gt))
 205                         continue; /* ignore incomplete engines */
 206
 207                 GEM_BUG_ON(engine->class >= ARRAY_SIZE(uabi_classes));
 208                 engine->uabi_class = uabi_classes[engine->class];
 209
 210                 GEM_BUG_ON(engine->uabi_class >= ARRAY_SIZE(uabi_instances));
 211                 engine->uabi_instance = uabi_instances[engine->uabi_class]++;
 212
 213                 /* Replace the internal name with the final user facing name */
 214                 memcpy(old, engine->name, sizeof(engine->name));
 215                 scnprintf(engine->name, sizeof(engine->name), "%s%u",
 216                           intel_engine_class_repr(engine->class),
 217                           engine->uabi_instance);
 218                 DRM_DEBUG_DRIVER("renamed %s to %s\n", old, engine->name);
 219
 220                 rb_link_node(&engine->uabi_node, prev, p);
 221                 rb_insert_color(&engine->uabi_node, &i915->uabi_engines);
 222
 223                 GEM_BUG_ON(intel_engine_lookup_user(i915,
 224                                                     engine->uabi_class,
 225                                                     engine->uabi_instance) != engine);
 226
 227                 /* Fix up the mapping to match default execbuf::user_map[] */
 228                 add_legacy_ring(&ring, engine);
 229
 230                 prev = &engine->uabi_node;
 231                 p = &prev->rb_right;
 232         }
 233
 234         if (IS_ENABLED(CONFIG_DRM_I915_SELFTESTS) &&
 235             IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)) {
 236                 struct intel_engine_cs *engine;
 237                 unsigned int isolation;
 238                 int class, inst;
 239                 int errors = 0;
 240
 241                 for (class = 0; class < ARRAY_SIZE(uabi_instances); class++) {
 242                         for (inst = 0; inst < uabi_instances[class]; inst++) {
 243                                 engine = intel_engine_lookup_user(i915,
 244                                                                   class, inst);
 245                                 if (!engine) {
 246                                         pr_err("UABI engine not found for { class:%d, instance:%d }\n",
 247                                                class, inst);
 248                                         errors++;
 249                                         continue;
 250                                 }
 251
 252                                 if (engine->uabi_class != class ||
 253                                     engine->uabi_instance != inst) {
 254                                         pr_err("Wrong UABI engine:%s { class:%d, instance:%d } found for { class:%d, instance:%d }\n",
 255                                                engine->name,
 256                                                engine->uabi_class,
 257                                                engine->uabi_instance,
 258                                                class, inst);
 259                                         errors++;
 260                                         continue;
 261                                 }
 262                         }
 263                 }
 264
 265                 /*
 266                  * Make sure that classes with multiple engine instances all
 267                  * share the same basic configuration.
 268                  */
 269                 isolation = intel_engines_has_context_isolation(i915);
 270                 for_each_uabi_engine(engine, i915) {
 271                         unsigned int bit = BIT(engine->uabi_class);
 272                         unsigned int expected = engine->default_state ? bit : 0;
 273
 274                         if ((isolation & bit) != expected) {
 275                                 pr_err("mismatching default context state for class %d on engine %s\n",
 276                                        engine->uabi_class, engine->name);
 277                                 errors++;
 278                         }
 279                 }
 280
 281                 if (drm_WARN(&i915->drm, errors,
 282                              "Invalid UABI engine mapping found"))
 283                         i915->uabi_engines = RB_ROOT;
 284         }
 285
 286         set_scheduler_caps(i915);
 287 }
 288
 289 unsigned int intel_engines_has_context_isolation(struct drm_i915_private *i915)
 290 {
 291         struct intel_engine_cs *engine;
 292         unsigned int which;
 293
 294         which = 0;
 295         for_each_uabi_engine(engine, i915)
 296                 if (engine->default_state)
 297                         which |= BIT(engine->uabi_class);
 298
 299         return which;
 300 }