1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2019 Intel Corporation
4  */
5 
6 #include <linux/list.h>
7 #include <linux/list_sort.h>
8 #include <linux/llist.h>
9 
10 #include "i915_drv.h"
11 #include "intel_engine.h"
12 #include "intel_engine_user.h"
13 #include "intel_gt.h"
14 #include "uc/intel_guc_submission.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 	[COMPUTE_CLASS] = I915_ENGINE_CLASS_COMPUTE,
51 };
52 
53 static int engine_cmp(void *priv, const struct list_head *A,
54 		      const struct list_head *B)
55 {
56 	const struct intel_engine_cs *a =
57 		container_of((struct rb_node *)A, typeof(*a), uabi_node);
58 	const struct intel_engine_cs *b =
59 		container_of((struct rb_node *)B, typeof(*b), uabi_node);
60 
61 	if (uabi_classes[a->class] < uabi_classes[b->class])
62 		return -1;
63 	if (uabi_classes[a->class] > uabi_classes[b->class])
64 		return 1;
65 
66 	if (a->instance < b->instance)
67 		return -1;
68 	if (a->instance > b->instance)
69 		return 1;
70 
71 	return 0;
72 }
73 
74 static struct llist_node *get_engines(struct drm_i915_private *i915)
75 {
76 	return llist_del_all((struct llist_head *)&i915->uabi_engines);
77 }
78 
79 static void sort_engines(struct drm_i915_private *i915,
80 			 struct list_head *engines)
81 {
82 	struct llist_node *pos, *next;
83 
84 	llist_for_each_safe(pos, next, get_engines(i915)) {
85 		struct intel_engine_cs *engine =
86 			container_of((struct rb_node *)pos, typeof(*engine),
87 				     uabi_node);
88 		list_add((struct list_head *)&engine->uabi_node, engines);
89 	}
90 	list_sort(NULL, engines, engine_cmp);
91 }
92 
93 static void set_scheduler_caps(struct drm_i915_private *i915)
94 {
95 	static const struct {
96 		u8 engine;
97 		u8 sched;
98 	} map[] = {
99 #define MAP(x, y) { ilog2(I915_ENGINE_##x), ilog2(I915_SCHEDULER_CAP_##y) }
100 		MAP(HAS_PREEMPTION, PREEMPTION),
101 		MAP(HAS_SEMAPHORES, SEMAPHORES),
102 		MAP(SUPPORTS_STATS, ENGINE_BUSY_STATS),
103 #undef MAP
104 	};
105 	struct intel_engine_cs *engine;
106 	u32 enabled, disabled;
107 
108 	enabled = 0;
109 	disabled = 0;
110 	for_each_uabi_engine(engine, i915) { /* all engines must agree! */
111 		int i;
112 
113 		if (engine->sched_engine->schedule)
114 			enabled |= (I915_SCHEDULER_CAP_ENABLED |
115 				    I915_SCHEDULER_CAP_PRIORITY);
116 		else
117 			disabled |= (I915_SCHEDULER_CAP_ENABLED |
118 				     I915_SCHEDULER_CAP_PRIORITY);
119 
120 		if (intel_uc_uses_guc_submission(&to_gt(i915)->uc))
121 			enabled |= I915_SCHEDULER_CAP_STATIC_PRIORITY_MAP;
122 
123 		for (i = 0; i < ARRAY_SIZE(map); i++) {
124 			if (engine->flags & BIT(map[i].engine))
125 				enabled |= BIT(map[i].sched);
126 			else
127 				disabled |= BIT(map[i].sched);
128 		}
129 	}
130 
131 	i915->caps.scheduler = enabled & ~disabled;
132 	if (!(i915->caps.scheduler & I915_SCHEDULER_CAP_ENABLED))
133 		i915->caps.scheduler = 0;
134 }
135 
136 const char *intel_engine_class_repr(u8 class)
137 {
138 	static const char * const uabi_names[] = {
139 		[RENDER_CLASS] = "rcs",
140 		[COPY_ENGINE_CLASS] = "bcs",
141 		[VIDEO_DECODE_CLASS] = "vcs",
142 		[VIDEO_ENHANCEMENT_CLASS] = "vecs",
143 		[OTHER_CLASS] = "other",
144 		[COMPUTE_CLASS] = "ccs",
145 	};
146 
147 	if (class >= ARRAY_SIZE(uabi_names) || !uabi_names[class])
148 		return "xxx";
149 
150 	return uabi_names[class];
151 }
152 
153 struct legacy_ring {
154 	struct intel_gt *gt;
155 	u8 class;
156 	u8 instance;
157 };
158 
159 static int legacy_ring_idx(const struct legacy_ring *ring)
160 {
161 	static const struct {
162 		u8 base, max;
163 	} map[] = {
164 		[RENDER_CLASS] = { RCS0, 1 },
165 		[COPY_ENGINE_CLASS] = { BCS0, 1 },
166 		[VIDEO_DECODE_CLASS] = { VCS0, I915_MAX_VCS },
167 		[VIDEO_ENHANCEMENT_CLASS] = { VECS0, I915_MAX_VECS },
168 		[COMPUTE_CLASS] = { CCS0, I915_MAX_CCS },
169 	};
170 
171 	if (GEM_DEBUG_WARN_ON(ring->class >= ARRAY_SIZE(map)))
172 		return INVALID_ENGINE;
173 
174 	if (GEM_DEBUG_WARN_ON(ring->instance >= map[ring->class].max))
175 		return INVALID_ENGINE;
176 
177 	return map[ring->class].base + ring->instance;
178 }
179 
180 static void add_legacy_ring(struct legacy_ring *ring,
181 			    struct intel_engine_cs *engine)
182 {
183 	if (engine->gt != ring->gt || engine->class != ring->class) {
184 		ring->gt = engine->gt;
185 		ring->class = engine->class;
186 		ring->instance = 0;
187 	}
188 
189 	engine->legacy_idx = legacy_ring_idx(ring);
190 	if (engine->legacy_idx != INVALID_ENGINE)
191 		ring->instance++;
192 }
193 
194 static void engine_rename(struct intel_engine_cs *engine, const char *name, u16 instance)
195 {
196 	char old[sizeof(engine->name)];
197 
198 	memcpy(old, engine->name, sizeof(engine->name));
199 	scnprintf(engine->name, sizeof(engine->name), "%s%u", name, instance);
200 	drm_dbg(&engine->i915->drm, "renamed %s to %s\n", old, engine->name);
201 }
202 
203 void intel_engines_driver_register(struct drm_i915_private *i915)
204 {
205 	struct legacy_ring ring = {};
206 	struct list_head *it, *next;
207 	struct rb_node **p, *prev;
208 	LIST_HEAD(engines);
209 
210 	sort_engines(i915, &engines);
211 
212 	prev = NULL;
213 	p = &i915->uabi_engines.rb_node;
214 	list_for_each_safe(it, next, &engines) {
215 		struct intel_engine_cs *engine =
216 			container_of((struct rb_node *)it, typeof(*engine),
217 				     uabi_node);
218 
219 		if (intel_gt_has_unrecoverable_error(engine->gt))
220 			continue; /* ignore incomplete engines */
221 
222 		/*
223 		 * We don't want to expose the GSC engine to the users, but we
224 		 * still rename it so it is easier to identify in the debug logs
225 		 */
226 		if (engine->id == GSC0) {
227 			engine_rename(engine, "gsc", 0);
228 			continue;
229 		}
230 
231 		GEM_BUG_ON(engine->class >= ARRAY_SIZE(uabi_classes));
232 		engine->uabi_class = uabi_classes[engine->class];
233 
234 		GEM_BUG_ON(engine->uabi_class >=
235 			   ARRAY_SIZE(i915->engine_uabi_class_count));
236 		engine->uabi_instance =
237 			i915->engine_uabi_class_count[engine->uabi_class]++;
238 
239 		/* Replace the internal name with the final user facing name */
240 		engine_rename(engine,
241 			      intel_engine_class_repr(engine->class),
242 			      engine->uabi_instance);
243 
244 		rb_link_node(&engine->uabi_node, prev, p);
245 		rb_insert_color(&engine->uabi_node, &i915->uabi_engines);
246 
247 		GEM_BUG_ON(intel_engine_lookup_user(i915,
248 						    engine->uabi_class,
249 						    engine->uabi_instance) != engine);
250 
251 		/* Fix up the mapping to match default execbuf::user_map[] */
252 		add_legacy_ring(&ring, engine);
253 
254 		prev = &engine->uabi_node;
255 		p = &prev->rb_right;
256 	}
257 
258 	if (IS_ENABLED(CONFIG_DRM_I915_SELFTESTS) &&
259 	    IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)) {
260 		struct intel_engine_cs *engine;
261 		unsigned int isolation;
262 		int class, inst;
263 		int errors = 0;
264 
265 		for (class = 0; class < ARRAY_SIZE(i915->engine_uabi_class_count); class++) {
266 			for (inst = 0; inst < i915->engine_uabi_class_count[class]; inst++) {
267 				engine = intel_engine_lookup_user(i915,
268 								  class, inst);
269 				if (!engine) {
270 					pr_err("UABI engine not found for { class:%d, instance:%d }\n",
271 					       class, inst);
272 					errors++;
273 					continue;
274 				}
275 
276 				if (engine->uabi_class != class ||
277 				    engine->uabi_instance != inst) {
278 					pr_err("Wrong UABI engine:%s { class:%d, instance:%d } found for { class:%d, instance:%d }\n",
279 					       engine->name,
280 					       engine->uabi_class,
281 					       engine->uabi_instance,
282 					       class, inst);
283 					errors++;
284 					continue;
285 				}
286 			}
287 		}
288 
289 		/*
290 		 * Make sure that classes with multiple engine instances all
291 		 * share the same basic configuration.
292 		 */
293 		isolation = intel_engines_has_context_isolation(i915);
294 		for_each_uabi_engine(engine, i915) {
295 			unsigned int bit = BIT(engine->uabi_class);
296 			unsigned int expected = engine->default_state ? bit : 0;
297 
298 			if ((isolation & bit) != expected) {
299 				pr_err("mismatching default context state for class %d on engine %s\n",
300 				       engine->uabi_class, engine->name);
301 				errors++;
302 			}
303 		}
304 
305 		if (drm_WARN(&i915->drm, errors,
306 			     "Invalid UABI engine mapping found"))
307 			i915->uabi_engines = RB_ROOT;
308 	}
309 
310 	set_scheduler_caps(i915);
311 }
312 
313 unsigned int intel_engines_has_context_isolation(struct drm_i915_private *i915)
314 {
315 	struct intel_engine_cs *engine;
316 	unsigned int which;
317 
318 	which = 0;
319 	for_each_uabi_engine(engine, i915)
320 		if (engine->default_state)
321 			which |= BIT(engine->uabi_class);
322 
323 	return which;
324 }
325