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 };
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->sched_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 		if (intel_uc_uses_guc_submission(&to_gt(i915)->uc))
120 			enabled |= I915_SCHEDULER_CAP_STATIC_PRIORITY_MAP;
121 
122 		for (i = 0; i < ARRAY_SIZE(map); i++) {
123 			if (engine->flags & BIT(map[i].engine))
124 				enabled |= BIT(map[i].sched);
125 			else
126 				disabled |= BIT(map[i].sched);
127 		}
128 	}
129 
130 	i915->caps.scheduler = enabled & ~disabled;
131 	if (!(i915->caps.scheduler & I915_SCHEDULER_CAP_ENABLED))
132 		i915->caps.scheduler = 0;
133 }
134 
135 const char *intel_engine_class_repr(u8 class)
136 {
137 	static const char * const uabi_names[] = {
138 		[RENDER_CLASS] = "rcs",
139 		[COPY_ENGINE_CLASS] = "bcs",
140 		[VIDEO_DECODE_CLASS] = "vcs",
141 		[VIDEO_ENHANCEMENT_CLASS] = "vecs",
142 	};
143 
144 	if (class >= ARRAY_SIZE(uabi_names) || !uabi_names[class])
145 		return "xxx";
146 
147 	return uabi_names[class];
148 }
149 
150 struct legacy_ring {
151 	struct intel_gt *gt;
152 	u8 class;
153 	u8 instance;
154 };
155 
156 static int legacy_ring_idx(const struct legacy_ring *ring)
157 {
158 	static const struct {
159 		u8 base, max;
160 	} map[] = {
161 		[RENDER_CLASS] = { RCS0, 1 },
162 		[COPY_ENGINE_CLASS] = { BCS0, 1 },
163 		[VIDEO_DECODE_CLASS] = { VCS0, I915_MAX_VCS },
164 		[VIDEO_ENHANCEMENT_CLASS] = { VECS0, I915_MAX_VECS },
165 	};
166 
167 	if (GEM_DEBUG_WARN_ON(ring->class >= ARRAY_SIZE(map)))
168 		return INVALID_ENGINE;
169 
170 	if (GEM_DEBUG_WARN_ON(ring->instance >= map[ring->class].max))
171 		return INVALID_ENGINE;
172 
173 	return map[ring->class].base + ring->instance;
174 }
175 
176 static void add_legacy_ring(struct legacy_ring *ring,
177 			    struct intel_engine_cs *engine)
178 {
179 	if (engine->gt != ring->gt || engine->class != ring->class) {
180 		ring->gt = engine->gt;
181 		ring->class = engine->class;
182 		ring->instance = 0;
183 	}
184 
185 	engine->legacy_idx = legacy_ring_idx(ring);
186 	if (engine->legacy_idx != INVALID_ENGINE)
187 		ring->instance++;
188 }
189 
190 void intel_engines_driver_register(struct drm_i915_private *i915)
191 {
192 	struct legacy_ring ring = {};
193 	u8 uabi_instances[4] = {};
194 	struct list_head *it, *next;
195 	struct rb_node **p, *prev;
196 	LIST_HEAD(engines);
197 
198 	sort_engines(i915, &engines);
199 
200 	prev = NULL;
201 	p = &i915->uabi_engines.rb_node;
202 	list_for_each_safe(it, next, &engines) {
203 		struct intel_engine_cs *engine =
204 			container_of((struct rb_node *)it, typeof(*engine),
205 				     uabi_node);
206 		char old[sizeof(engine->name)];
207 
208 		if (intel_gt_has_unrecoverable_error(engine->gt))
209 			continue; /* ignore incomplete engines */
210 
211 		GEM_BUG_ON(engine->class >= ARRAY_SIZE(uabi_classes));
212 		engine->uabi_class = uabi_classes[engine->class];
213 
214 		GEM_BUG_ON(engine->uabi_class >= ARRAY_SIZE(uabi_instances));
215 		engine->uabi_instance = uabi_instances[engine->uabi_class]++;
216 
217 		/* Replace the internal name with the final user facing name */
218 		memcpy(old, engine->name, sizeof(engine->name));
219 		scnprintf(engine->name, sizeof(engine->name), "%s%u",
220 			  intel_engine_class_repr(engine->class),
221 			  engine->uabi_instance);
222 		DRM_DEBUG_DRIVER("renamed %s to %s\n", old, engine->name);
223 
224 		rb_link_node(&engine->uabi_node, prev, p);
225 		rb_insert_color(&engine->uabi_node, &i915->uabi_engines);
226 
227 		GEM_BUG_ON(intel_engine_lookup_user(i915,
228 						    engine->uabi_class,
229 						    engine->uabi_instance) != engine);
230 
231 		/* Fix up the mapping to match default execbuf::user_map[] */
232 		add_legacy_ring(&ring, engine);
233 
234 		prev = &engine->uabi_node;
235 		p = &prev->rb_right;
236 	}
237 
238 	if (IS_ENABLED(CONFIG_DRM_I915_SELFTESTS) &&
239 	    IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)) {
240 		struct intel_engine_cs *engine;
241 		unsigned int isolation;
242 		int class, inst;
243 		int errors = 0;
244 
245 		for (class = 0; class < ARRAY_SIZE(uabi_instances); class++) {
246 			for (inst = 0; inst < uabi_instances[class]; inst++) {
247 				engine = intel_engine_lookup_user(i915,
248 								  class, inst);
249 				if (!engine) {
250 					pr_err("UABI engine not found for { class:%d, instance:%d }\n",
251 					       class, inst);
252 					errors++;
253 					continue;
254 				}
255 
256 				if (engine->uabi_class != class ||
257 				    engine->uabi_instance != inst) {
258 					pr_err("Wrong UABI engine:%s { class:%d, instance:%d } found for { class:%d, instance:%d }\n",
259 					       engine->name,
260 					       engine->uabi_class,
261 					       engine->uabi_instance,
262 					       class, inst);
263 					errors++;
264 					continue;
265 				}
266 			}
267 		}
268 
269 		/*
270 		 * Make sure that classes with multiple engine instances all
271 		 * share the same basic configuration.
272 		 */
273 		isolation = intel_engines_has_context_isolation(i915);
274 		for_each_uabi_engine(engine, i915) {
275 			unsigned int bit = BIT(engine->uabi_class);
276 			unsigned int expected = engine->default_state ? bit : 0;
277 
278 			if ((isolation & bit) != expected) {
279 				pr_err("mismatching default context state for class %d on engine %s\n",
280 				       engine->uabi_class, engine->name);
281 				errors++;
282 			}
283 		}
284 
285 		if (drm_WARN(&i915->drm, errors,
286 			     "Invalid UABI engine mapping found"))
287 			i915->uabi_engines = RB_ROOT;
288 	}
289 
290 	set_scheduler_caps(i915);
291 }
292 
293 unsigned int intel_engines_has_context_isolation(struct drm_i915_private *i915)
294 {
295 	struct intel_engine_cs *engine;
296 	unsigned int which;
297 
298 	which = 0;
299 	for_each_uabi_engine(engine, i915)
300 		if (engine->default_state)
301 			which |= BIT(engine->uabi_class);
302 
303 	return which;
304 }
305