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
 16struct intel_engine_cs *
 17intel_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
 39void 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
 45static 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
 52static 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
 72static struct llist_node *get_engines(struct drm_i915_private *i915)
 73{
 74	return llist_del_all((struct llist_head *)&i915->uabi_engines);
 75}
 76
 77static 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
 91static 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
131const 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
146struct legacy_ring {
147	struct intel_gt *gt;
148	u8 class;
149	u8 instance;
150};
151
152static 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
172static 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
186void 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
289unsigned 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}