xref: /linux/drivers/gpu/drm/i915/i915_pmu.h (revision 409c38d4f156740bf3165fd6ceae4fa6425eebf4)
1 /*
2  * SPDX-License-Identifier: MIT
3  *
4  * Copyright © 2017-2018 Intel Corporation
5  */
6 
7 #ifndef __I915_PMU_H__
8 #define __I915_PMU_H__
9 
10 #include <linux/hrtimer.h>
11 #include <linux/perf_event.h>
12 #include <linux/spinlock_types.h>
13 #include <uapi/drm/i915_drm.h>
14 
15 struct drm_i915_private;
16 struct intel_gt;
17 
18 /*
19  * Non-engine events that we need to track enabled-disabled transition and
20  * current state.
21  */
22 enum i915_pmu_tracked_events {
23 	__I915_PMU_ACTUAL_FREQUENCY_ENABLED = 0,
24 	__I915_PMU_REQUESTED_FREQUENCY_ENABLED,
25 	__I915_PMU_RC6_RESIDENCY_ENABLED,
26 	__I915_PMU_TRACKED_EVENT_COUNT, /* count marker */
27 };
28 
29 /*
30  * Slots used from the sampling timer (non-engine events) with some extras for
31  * convenience.
32  */
33 enum {
34 	__I915_SAMPLE_FREQ_ACT = 0,
35 	__I915_SAMPLE_FREQ_REQ,
36 	__I915_SAMPLE_RC6,
37 	__I915_SAMPLE_RC6_LAST_REPORTED,
38 	__I915_NUM_PMU_SAMPLERS
39 };
40 
41 #define I915_PMU_MAX_GT 2
42 
43 /*
44  * How many different events we track in the global PMU mask.
45  *
46  * It is also used to know to needed number of event reference counters.
47  */
48 #define I915_PMU_MASK_BITS \
49 	(I915_ENGINE_SAMPLE_COUNT + \
50 	 I915_PMU_MAX_GT * __I915_PMU_TRACKED_EVENT_COUNT)
51 
52 #define I915_ENGINE_SAMPLE_COUNT (I915_SAMPLE_SEMA + 1)
53 
54 struct i915_pmu_sample {
55 	u64 cur;
56 };
57 
58 struct i915_pmu {
59 	/**
60 	 * @cpuhp: Struct used for CPU hotplug handling.
61 	 */
62 	struct {
63 		struct hlist_node node;
64 		unsigned int cpu;
65 	} cpuhp;
66 	/**
67 	 * @base: PMU base.
68 	 */
69 	struct pmu base;
70 	/**
71 	 * @closed: i915 is unregistering.
72 	 */
73 	bool closed;
74 	/**
75 	 * @name: Name as registered with perf core.
76 	 */
77 	const char *name;
78 	/**
79 	 * @lock: Lock protecting enable mask and ref count handling.
80 	 */
81 	spinlock_t lock;
82 	/**
83 	 * @unparked: GT unparked mask.
84 	 */
85 	unsigned int unparked;
86 	/**
87 	 * @timer: Timer for internal i915 PMU sampling.
88 	 */
89 	struct hrtimer timer;
90 	/**
91 	 * @enable: Bitmask of specific enabled events.
92 	 *
93 	 * For some events we need to track their state and do some internal
94 	 * house keeping.
95 	 *
96 	 * Each engine event sampler type and event listed in enum
97 	 * i915_pmu_tracked_events gets a bit in this field.
98 	 *
99 	 * Low bits are engine samplers and other events continue from there.
100 	 */
101 	u32 enable;
102 
103 	/**
104 	 * @timer_last:
105 	 *
106 	 * Timestmap of the previous timer invocation.
107 	 */
108 	ktime_t timer_last;
109 
110 	/**
111 	 * @enable_count: Reference counts for the enabled events.
112 	 *
113 	 * Array indices are mapped in the same way as bits in the @enable field
114 	 * and they are used to control sampling on/off when multiple clients
115 	 * are using the PMU API.
116 	 */
117 	unsigned int enable_count[I915_PMU_MASK_BITS];
118 	/**
119 	 * @timer_enabled: Should the internal sampling timer be running.
120 	 */
121 	bool timer_enabled;
122 	/**
123 	 * @sample: Current and previous (raw) counters for sampling events.
124 	 *
125 	 * These counters are updated from the i915 PMU sampling timer.
126 	 *
127 	 * Only global counters are held here, while the per-engine ones are in
128 	 * struct intel_engine_cs.
129 	 */
130 	struct i915_pmu_sample sample[I915_PMU_MAX_GT][__I915_NUM_PMU_SAMPLERS];
131 	/**
132 	 * @sleep_last: Last time GT parked for RC6 estimation.
133 	 */
134 	ktime_t sleep_last[I915_PMU_MAX_GT];
135 	/**
136 	 * @irq_count: Number of interrupts
137 	 *
138 	 * Intentionally unsigned long to avoid atomics or heuristics on 32bit.
139 	 * 4e9 interrupts are a lot and postprocessing can really deal with an
140 	 * occasional wraparound easily. It's 32bit after all.
141 	 */
142 	unsigned long irq_count;
143 	/**
144 	 * @events_attr_group: Device events attribute group.
145 	 */
146 	struct attribute_group events_attr_group;
147 	/**
148 	 * @i915_attr: Memory block holding device attributes.
149 	 */
150 	void *i915_attr;
151 	/**
152 	 * @pmu_attr: Memory block holding device attributes.
153 	 */
154 	void *pmu_attr;
155 };
156 
157 #ifdef CONFIG_PERF_EVENTS
158 int i915_pmu_init(void);
159 void i915_pmu_exit(void);
160 void i915_pmu_register(struct drm_i915_private *i915);
161 void i915_pmu_unregister(struct drm_i915_private *i915);
162 void i915_pmu_gt_parked(struct intel_gt *gt);
163 void i915_pmu_gt_unparked(struct intel_gt *gt);
164 #else
165 static inline int i915_pmu_init(void) { return 0; }
166 static inline void i915_pmu_exit(void) {}
167 static inline void i915_pmu_register(struct drm_i915_private *i915) {}
168 static inline void i915_pmu_unregister(struct drm_i915_private *i915) {}
169 static inline void i915_pmu_gt_parked(struct intel_gt *gt) {}
170 static inline void i915_pmu_gt_unparked(struct intel_gt *gt) {}
171 #endif
172 
173 #endif
174