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, const struct list_head *A,
  53                       const struct list_head *B)
  54 {
  55         const struct intel_engine_cs *a =
  56                 container_of((struct rb_node *)A, typeof(*a), uabi_node);
  57         const struct intel_engine_cs *b =
  58                 container_of((struct rb_node *)B, typeof(*b), uabi_node);
  59
  60         if (uabi_classes[a->class] < uabi_classes[b->class])
  61                 return -1;
  62         if (uabi_classes[a->class] > uabi_classes[b->class])
  63                 return 1;
  64
  65         if (a->instance < b->instance)
  66                 return -1;
  67         if (a->instance > b->instance)
  68                 return 1;
  69
  70         return 0;
  71 }
  72
  73 static struct llist_node *get_engines(struct drm_i915_private *i915)
  74 {
  75         return llist_del_all((struct llist_head *)&i915->uabi_engines);
  76 }
  77
  78 static void sort_engines(struct drm_i915_private *i915,
  79                          struct list_head *engines)
  80 {
  81         struct llist_node *pos, *next;
  82
  83         llist_for_each_safe(pos, next, get_engines(i915)) {
  84                 struct intel_engine_cs *engine =
  85                         container_of((struct rb_node *)pos, typeof(*engine),
  86                                      uabi_node);
  87                 list_add((struct list_head *)&engine->uabi_node, engines);
  88         }
  89         list_sort(NULL, engines, engine_cmp);
  90 }
  91
  92 static void set_scheduler_caps(struct drm_i915_private *i915)
  93 {
  94         static const struct {
  95                 u8 engine;
  96                 u8 sched;
  97         } map[] = {
  98 #define MAP(x, y) { ilog2(I915_ENGINE_##x), ilog2(I915_SCHEDULER_CAP_##y) }
  99                 MAP(HAS_PREEMPTION, PREEMPTION),
 100                 MAP(HAS_SEMAPHORES, SEMAPHORES),
 101                 MAP(SUPPORTS_STATS, ENGINE_BUSY_STATS),
 102 #undef MAP
 103         };
 104         struct intel_engine_cs *engine;
 105         u32 enabled, disabled;
 106
 107         enabled = 0;
 108         disabled = 0;
 109         for_each_uabi_engine(engine, i915) { /* all engines must agree! */
 110                 int i;
 111
 112                 if (engine->schedule)
 113                         enabled |= (I915_SCHEDULER_CAP_ENABLED |
 114                                     I915_SCHEDULER_CAP_PRIORITY);
 115                 else
 116                         disabled |= (I915_SCHEDULER_CAP_ENABLED |
 117                                      I915_SCHEDULER_CAP_PRIORITY);
 118
 119                 for (i = 0; i < ARRAY_SIZE(map); i++) {
 120                         if (engine->flags & BIT(map[i].engine))
 121                                 enabled |= BIT(map[i].sched);
 122                         else
 123                                 disabled |= BIT(map[i].sched);
 124                 }
 125         }
 126
 127         i915->caps.scheduler = enabled & ~disabled;
 128         if (!(i915->caps.scheduler & I915_SCHEDULER_CAP_ENABLED))
 129                 i915->caps.scheduler = 0;
 130 }
 131
 132 const char *intel_engine_class_repr(u8 class)
 133 {
 134         static const char * const uabi_names[] = {
 135                 [RENDER_CLASS] = "rcs",
 136                 [COPY_ENGINE_CLASS] = "bcs",
 137                 [VIDEO_DECODE_CLASS] = "vcs",
 138                 [VIDEO_ENHANCEMENT_CLASS] = "vecs",
 139         };
 140
 141         if (class >= ARRAY_SIZE(uabi_names) || !uabi_names[class])
 142                 return "xxx";
 143
 144         return uabi_names[class];
 145 }
 146
 147 struct legacy_ring {
 148         struct intel_gt *gt;
 149         u8 class;
 150         u8 instance;
 151 };
 152
 153 static int legacy_ring_idx(const struct legacy_ring *ring)
 154 {
 155         static const struct {
 156                 u8 base, max;
 157         } map[] = {
 158                 [RENDER_CLASS] = { RCS0, 1 },
 159                 [COPY_ENGINE_CLASS] = { BCS0, 1 },
 160                 [VIDEO_DECODE_CLASS] = { VCS0, I915_MAX_VCS },
 161                 [VIDEO_ENHANCEMENT_CLASS] = { VECS0, I915_MAX_VECS },
 162         };
 163
 164         if (GEM_DEBUG_WARN_ON(ring->class >= ARRAY_SIZE(map)))
 165                 return INVALID_ENGINE;
 166
 167         if (GEM_DEBUG_WARN_ON(ring->instance >= map[ring->class].max))
 168                 return INVALID_ENGINE;
 169
 170         return map[ring->class].base + ring->instance;
 171 }
 172
 173 static void add_legacy_ring(struct legacy_ring *ring,
 174                             struct intel_engine_cs *engine)
 175 {
 176         if (engine->gt != ring->gt || engine->class != ring->class) {
 177                 ring->gt = engine->gt;
 178                 ring->class = engine->class;
 179                 ring->instance = 0;
 180         }
 181
 182         engine->legacy_idx = legacy_ring_idx(ring);
 183         if (engine->legacy_idx != INVALID_ENGINE)
 184                 ring->instance++;
 185 }
 186
 187 void intel_engines_driver_register(struct drm_i915_private *i915)
 188 {
 189         struct legacy_ring ring = {};
 190         u8 uabi_instances[4] = {};
 191         struct list_head *it, *next;
 192         struct rb_node **p, *prev;
 193         LIST_HEAD(engines);
 194
 195         sort_engines(i915, &engines);
 196
 197         prev = NULL;
 198         p = &i915->uabi_engines.rb_node;
 199         list_for_each_safe(it, next, &engines) {
 200                 struct intel_engine_cs *engine =
 201                         container_of((struct rb_node *)it, typeof(*engine),
 202                                      uabi_node);
 203                 char old[sizeof(engine->name)];
 204
 205                 if (intel_gt_has_unrecoverable_error(engine->gt))
 206                         continue; /* ignore incomplete engines */
 207
 208                 GEM_BUG_ON(engine->class >= ARRAY_SIZE(uabi_classes));
 209                 engine->uabi_class = uabi_classes[engine->class];
 210
 211                 GEM_BUG_ON(engine->uabi_class >= ARRAY_SIZE(uabi_instances));
 212                 engine->uabi_instance = uabi_instances[engine->uabi_class]++;
 213
 214                 /* Replace the internal name with the final user facing name */
 215                 memcpy(old, engine->name, sizeof(engine->name));
 216                 scnprintf(engine->name, sizeof(engine->name), "%s%u",
 217                           intel_engine_class_repr(engine->class),
 218                           engine->uabi_instance);
 219                 DRM_DEBUG_DRIVER("renamed %s to %s\n", old, engine->name);
 220
 221                 rb_link_node(&engine->uabi_node, prev, p);
 222                 rb_insert_color(&engine->uabi_node, &i915->uabi_engines);
 223
 224                 GEM_BUG_ON(intel_engine_lookup_user(i915,
 225                                                     engine->uabi_class,
 226                                                     engine->uabi_instance) != engine);
 227
 228                 /* Fix up the mapping to match default execbuf::user_map[] */
 229                 add_legacy_ring(&ring, engine);
 230
 231                 prev = &engine->uabi_node;
 232                 p = &prev->rb_right;
 233         }
 234
 235         if (IS_ENABLED(CONFIG_DRM_I915_SELFTESTS) &&
 236             IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)) {
 237                 struct intel_engine_cs *engine;
 238                 unsigned int isolation;
 239                 int class, inst;
 240                 int errors = 0;
 241
 242                 for (class = 0; class < ARRAY_SIZE(uabi_instances); class++) {
 243                         for (inst = 0; inst < uabi_instances[class]; inst++) {
 244                                 engine = intel_engine_lookup_user(i915,
 245                                                                   class, inst);
 246                                 if (!engine) {
 247                                         pr_err("UABI engine not found for { class:%d, instance:%d }\n",
 248                                                class, inst);
 249                                         errors++;
 250                                         continue;
 251                                 }
 252
 253                                 if (engine->uabi_class != class ||
 254                                     engine->uabi_instance != inst) {
 255                                         pr_err("Wrong UABI engine:%s { class:%d, instance:%d } found for { class:%d, instance:%d }\n",
 256                                                engine->name,
 257                                                engine->uabi_class,
 258                                                engine->uabi_instance,
 259                                                class, inst);
 260                                         errors++;
 261                                         continue;
 262                                 }
 263                         }
 264                 }
 265
 266                 /*
 267                  * Make sure that classes with multiple engine instances all
 268                  * share the same basic configuration.
 269                  */
 270                 isolation = intel_engines_has_context_isolation(i915);
 271                 for_each_uabi_engine(engine, i915) {
 272                         unsigned int bit = BIT(engine->uabi_class);
 273                         unsigned int expected = engine->default_state ? bit : 0;
 274
 275                         if ((isolation & bit) != expected) {
 276                                 pr_err("mismatching default context state for class %d on engine %s\n",
 277                                        engine->uabi_class, engine->name);
 278                                 errors++;
 279                         }
 280                 }
 281
 282                 if (drm_WARN(&i915->drm, errors,
 283                              "Invalid UABI engine mapping found"))
 284                         i915->uabi_engines = RB_ROOT;
 285         }
 286
 287         set_scheduler_caps(i915);
 288 }
 289
 290 unsigned int intel_engines_has_context_isolation(struct drm_i915_private *i915)
 291 {
 292         struct intel_engine_cs *engine;
 293         unsigned int which;
 294
 295         which = 0;
 296         for_each_uabi_engine(engine, i915)
 297                 if (engine->default_state)
 298                         which |= BIT(engine->uabi_class);
 299
 300         return which;
 301 }