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 *
intel_engine_lookup_user(struct drm_i915_private * i915,u8 class,u8 instance)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 
intel_engine_add_user(struct intel_engine_cs * engine)39 void intel_engine_add_user(struct intel_engine_cs *engine)
40 {
41 	llist_add(&engine->uabi_llist, &engine->i915->uabi_engines_llist);
42 }
43 
44 #define I915_NO_UABI_CLASS ((u16)(-1))
45 
46 static const u16 uabi_classes[] = {
47 	[RENDER_CLASS] = I915_ENGINE_CLASS_RENDER,
48 	[COPY_ENGINE_CLASS] = I915_ENGINE_CLASS_COPY,
49 	[VIDEO_DECODE_CLASS] = I915_ENGINE_CLASS_VIDEO,
50 	[VIDEO_ENHANCEMENT_CLASS] = I915_ENGINE_CLASS_VIDEO_ENHANCE,
51 	[COMPUTE_CLASS] = I915_ENGINE_CLASS_COMPUTE,
52 	[OTHER_CLASS] = I915_NO_UABI_CLASS, /* Not exposed to users, no uabi class. */
53 };
54 
engine_cmp(void * priv,const struct list_head * A,const struct list_head * B)55 static int engine_cmp(void *priv, const struct list_head *A,
56 		      const struct list_head *B)
57 {
58 	const struct intel_engine_cs *a =
59 		container_of(A, typeof(*a), uabi_list);
60 	const struct intel_engine_cs *b =
61 		container_of(B, typeof(*b), uabi_list);
62 
63 	if (uabi_classes[a->class] < uabi_classes[b->class])
64 		return -1;
65 	if (uabi_classes[a->class] > uabi_classes[b->class])
66 		return 1;
67 
68 	if (a->instance < b->instance)
69 		return -1;
70 	if (a->instance > b->instance)
71 		return 1;
72 
73 	return 0;
74 }
75 
get_engines(struct drm_i915_private * i915)76 static struct llist_node *get_engines(struct drm_i915_private *i915)
77 {
78 	return llist_del_all(&i915->uabi_engines_llist);
79 }
80 
sort_engines(struct drm_i915_private * i915,struct list_head * engines)81 static void sort_engines(struct drm_i915_private *i915,
82 			 struct list_head *engines)
83 {
84 	struct llist_node *pos, *next;
85 
86 	llist_for_each_safe(pos, next, get_engines(i915)) {
87 		struct intel_engine_cs *engine =
88 			container_of(pos, typeof(*engine), uabi_llist);
89 		list_add(&engine->uabi_list, engines);
90 	}
91 	list_sort(NULL, engines, engine_cmp);
92 }
93 
94 #ifdef __linux__
set_scheduler_caps(struct drm_i915_private * i915)95 static void set_scheduler_caps(struct drm_i915_private *i915)
96 {
97 	static const struct {
98 		u8 engine;
99 		u8 sched;
100 	} map[] = {
101 #define MAP(x, y) { ilog2(I915_ENGINE_##x), ilog2(I915_SCHEDULER_CAP_##y) }
102 		MAP(HAS_PREEMPTION, PREEMPTION),
103 		MAP(HAS_SEMAPHORES, SEMAPHORES),
104 		MAP(SUPPORTS_STATS, ENGINE_BUSY_STATS),
105 #undef MAP
106 	};
107 	struct intel_engine_cs *engine;
108 	u32 enabled, disabled;
109 
110 	enabled = 0;
111 	disabled = 0;
112 	for_each_uabi_engine(engine, i915) { /* all engines must agree! */
113 		int i;
114 
115 		if (engine->sched_engine->schedule)
116 			enabled |= (I915_SCHEDULER_CAP_ENABLED |
117 				    I915_SCHEDULER_CAP_PRIORITY);
118 		else
119 			disabled |= (I915_SCHEDULER_CAP_ENABLED |
120 				     I915_SCHEDULER_CAP_PRIORITY);
121 
122 		if (intel_uc_uses_guc_submission(&engine->gt->uc))
123 			enabled |= I915_SCHEDULER_CAP_STATIC_PRIORITY_MAP;
124 
125 		for (i = 0; i < ARRAY_SIZE(map); i++) {
126 			if (engine->flags & BIT(map[i].engine))
127 				enabled |= BIT(map[i].sched);
128 			else
129 				disabled |= BIT(map[i].sched);
130 		}
131 	}
132 
133 	i915->caps.scheduler = enabled & ~disabled;
134 	if (!(i915->caps.scheduler & I915_SCHEDULER_CAP_ENABLED))
135 		i915->caps.scheduler = 0;
136 }
137 #else
138 /* without the pointless ilog2 -> BIT() */
set_scheduler_caps(struct drm_i915_private * i915)139 static void set_scheduler_caps(struct drm_i915_private *i915)
140 {
141 	static const struct {
142 		u8 engine;
143 		u8 sched;
144 	} map[] = {
145 #define MAP(x, y) { I915_ENGINE_##x, I915_SCHEDULER_CAP_##y }
146 		MAP(HAS_PREEMPTION, PREEMPTION),
147 		MAP(HAS_SEMAPHORES, SEMAPHORES),
148 		MAP(SUPPORTS_STATS, ENGINE_BUSY_STATS),
149 #undef MAP
150 	};
151 	struct intel_engine_cs *engine;
152 	u32 enabled, disabled;
153 
154 	enabled = 0;
155 	disabled = 0;
156 	for_each_uabi_engine(engine, i915) { /* all engines must agree! */
157 		int i;
158 
159 		if (engine->sched_engine->schedule)
160 			enabled |= (I915_SCHEDULER_CAP_ENABLED |
161 				    I915_SCHEDULER_CAP_PRIORITY);
162 		else
163 			disabled |= (I915_SCHEDULER_CAP_ENABLED |
164 				     I915_SCHEDULER_CAP_PRIORITY);
165 
166 		if (intel_uc_uses_guc_submission(&engine->gt->uc))
167 			enabled |= I915_SCHEDULER_CAP_STATIC_PRIORITY_MAP;
168 
169 		for (i = 0; i < ARRAY_SIZE(map); i++) {
170 			if (engine->flags & map[i].engine)
171 				enabled |= map[i].sched;
172 			else
173 				disabled |= map[i].sched;
174 		}
175 	}
176 
177 	i915->caps.scheduler = enabled & ~disabled;
178 	if (!(i915->caps.scheduler & I915_SCHEDULER_CAP_ENABLED))
179 		i915->caps.scheduler = 0;
180 }
181 #endif
182 
intel_engine_class_repr(u8 class)183 const char *intel_engine_class_repr(u8 class)
184 {
185 	static const char * const uabi_names[] = {
186 		[RENDER_CLASS] = "rcs",
187 		[COPY_ENGINE_CLASS] = "bcs",
188 		[VIDEO_DECODE_CLASS] = "vcs",
189 		[VIDEO_ENHANCEMENT_CLASS] = "vecs",
190 		[OTHER_CLASS] = "other",
191 		[COMPUTE_CLASS] = "ccs",
192 	};
193 
194 	if (class >= ARRAY_SIZE(uabi_names) || !uabi_names[class])
195 		return "xxx";
196 
197 	return uabi_names[class];
198 }
199 
200 struct legacy_ring {
201 	struct intel_gt *gt;
202 	u8 class;
203 	u8 instance;
204 };
205 
legacy_ring_idx(const struct legacy_ring * ring)206 static int legacy_ring_idx(const struct legacy_ring *ring)
207 {
208 	static const struct {
209 		u8 base, max;
210 	} map[] = {
211 		[RENDER_CLASS] = { RCS0, 1 },
212 		[COPY_ENGINE_CLASS] = { BCS0, 1 },
213 		[VIDEO_DECODE_CLASS] = { VCS0, I915_MAX_VCS },
214 		[VIDEO_ENHANCEMENT_CLASS] = { VECS0, I915_MAX_VECS },
215 		[COMPUTE_CLASS] = { CCS0, I915_MAX_CCS },
216 	};
217 
218 	if (GEM_DEBUG_WARN_ON(ring->class >= ARRAY_SIZE(map)))
219 		return INVALID_ENGINE;
220 
221 	if (GEM_DEBUG_WARN_ON(ring->instance >= map[ring->class].max))
222 		return INVALID_ENGINE;
223 
224 	return map[ring->class].base + ring->instance;
225 }
226 
add_legacy_ring(struct legacy_ring * ring,struct intel_engine_cs * engine)227 static void add_legacy_ring(struct legacy_ring *ring,
228 			    struct intel_engine_cs *engine)
229 {
230 	if (engine->gt != ring->gt || engine->class != ring->class) {
231 		ring->gt = engine->gt;
232 		ring->class = engine->class;
233 		ring->instance = 0;
234 	}
235 
236 	engine->legacy_idx = legacy_ring_idx(ring);
237 	if (engine->legacy_idx != INVALID_ENGINE)
238 		ring->instance++;
239 }
240 
engine_rename(struct intel_engine_cs * engine,const char * name,u16 instance)241 static void engine_rename(struct intel_engine_cs *engine, const char *name, u16 instance)
242 {
243 	char old[sizeof(engine->name)];
244 
245 	memcpy(old, engine->name, sizeof(engine->name));
246 	scnprintf(engine->name, sizeof(engine->name), "%s%u", name, instance);
247 	drm_dbg(&engine->i915->drm, "renamed %s to %s\n", old, engine->name);
248 }
249 
intel_engines_driver_register(struct drm_i915_private * i915)250 void intel_engines_driver_register(struct drm_i915_private *i915)
251 {
252 	u16 name_instance, other_instance = 0;
253 	struct legacy_ring ring = {};
254 	struct list_head *it, *next;
255 	struct rb_node **p, *prev;
256 	DRM_LIST_HEAD(engines);
257 
258 	sort_engines(i915, &engines);
259 
260 	prev = NULL;
261 	p = &i915->uabi_engines.rb_node;
262 	list_for_each_safe(it, next, &engines) {
263 		struct intel_engine_cs *engine =
264 			container_of(it, typeof(*engine), uabi_list);
265 
266 		if (intel_gt_has_unrecoverable_error(engine->gt))
267 			continue; /* ignore incomplete engines */
268 
269 		GEM_BUG_ON(engine->class >= ARRAY_SIZE(uabi_classes));
270 		engine->uabi_class = uabi_classes[engine->class];
271 		if (engine->uabi_class == I915_NO_UABI_CLASS) {
272 			name_instance = other_instance++;
273 		} else {
274 			GEM_BUG_ON(engine->uabi_class >=
275 				   ARRAY_SIZE(i915->engine_uabi_class_count));
276 			name_instance =
277 				i915->engine_uabi_class_count[engine->uabi_class]++;
278 		}
279 		engine->uabi_instance = name_instance;
280 
281 		/*
282 		 * Replace the internal name with the final user and log facing
283 		 * name.
284 		 */
285 		engine_rename(engine,
286 			      intel_engine_class_repr(engine->class),
287 			      name_instance);
288 
289 		if (engine->uabi_class == I915_NO_UABI_CLASS)
290 			continue;
291 
292 		rb_link_node(&engine->uabi_node, prev, p);
293 		rb_insert_color(&engine->uabi_node, &i915->uabi_engines);
294 
295 		GEM_BUG_ON(intel_engine_lookup_user(i915,
296 						    engine->uabi_class,
297 						    engine->uabi_instance) != engine);
298 
299 		/* Fix up the mapping to match default execbuf::user_map[] */
300 		add_legacy_ring(&ring, engine);
301 
302 		prev = &engine->uabi_node;
303 		p = &prev->rb_right;
304 	}
305 
306 	if (IS_ENABLED(CONFIG_DRM_I915_SELFTESTS) &&
307 	    IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)) {
308 		struct intel_engine_cs *engine;
309 		unsigned int isolation;
310 		int class, inst;
311 		int errors = 0;
312 
313 		for (class = 0; class < ARRAY_SIZE(i915->engine_uabi_class_count); class++) {
314 			for (inst = 0; inst < i915->engine_uabi_class_count[class]; inst++) {
315 				engine = intel_engine_lookup_user(i915,
316 								  class, inst);
317 				if (!engine) {
318 					pr_err("UABI engine not found for { class:%d, instance:%d }\n",
319 					       class, inst);
320 					errors++;
321 					continue;
322 				}
323 
324 				if (engine->uabi_class != class ||
325 				    engine->uabi_instance != inst) {
326 					pr_err("Wrong UABI engine:%s { class:%d, instance:%d } found for { class:%d, instance:%d }\n",
327 					       engine->name,
328 					       engine->uabi_class,
329 					       engine->uabi_instance,
330 					       class, inst);
331 					errors++;
332 					continue;
333 				}
334 			}
335 		}
336 
337 		/*
338 		 * Make sure that classes with multiple engine instances all
339 		 * share the same basic configuration.
340 		 */
341 		isolation = intel_engines_has_context_isolation(i915);
342 		for_each_uabi_engine(engine, i915) {
343 			unsigned int bit = BIT(engine->uabi_class);
344 			unsigned int expected = engine->default_state ? bit : 0;
345 
346 			if ((isolation & bit) != expected) {
347 				pr_err("mismatching default context state for class %d on engine %s\n",
348 				       engine->uabi_class, engine->name);
349 				errors++;
350 			}
351 		}
352 
353 		if (drm_WARN(&i915->drm, errors,
354 			     "Invalid UABI engine mapping found"))
355 			i915->uabi_engines = RB_ROOT;
356 	}
357 
358 	set_scheduler_caps(i915);
359 }
360 
intel_engines_has_context_isolation(struct drm_i915_private * i915)361 unsigned int intel_engines_has_context_isolation(struct drm_i915_private *i915)
362 {
363 	struct intel_engine_cs *engine;
364 	unsigned int which;
365 
366 	which = 0;
367 	for_each_uabi_engine(engine, i915)
368 		if (engine->default_state)
369 			which |= BIT(engine->uabi_class);
370 
371 	return which;
372 }
373