xref: /openbmc/linux/drivers/gpu/drm/i915/i915_pmu.h (revision 5e0266f0)
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 
17 /**
18  * Non-engine events that we need to track enabled-disabled transition and
19  * current state.
20  */
21 enum i915_pmu_tracked_events {
22 	__I915_PMU_ACTUAL_FREQUENCY_ENABLED = 0,
23 	__I915_PMU_REQUESTED_FREQUENCY_ENABLED,
24 	__I915_PMU_RC6_RESIDENCY_ENABLED,
25 	__I915_PMU_TRACKED_EVENT_COUNT, /* count marker */
26 };
27 
28 /**
29  * Slots used from the sampling timer (non-engine events) with some extras for
30  * convenience.
31  */
32 enum {
33 	__I915_SAMPLE_FREQ_ACT = 0,
34 	__I915_SAMPLE_FREQ_REQ,
35 	__I915_SAMPLE_RC6,
36 	__I915_SAMPLE_RC6_LAST_REPORTED,
37 	__I915_NUM_PMU_SAMPLERS
38 };
39 
40 /**
41  * How many different events we track in the global PMU mask.
42  *
43  * It is also used to know to needed number of event reference counters.
44  */
45 #define I915_PMU_MASK_BITS \
46 	(I915_ENGINE_SAMPLE_COUNT + __I915_PMU_TRACKED_EVENT_COUNT)
47 
48 #define I915_ENGINE_SAMPLE_COUNT (I915_SAMPLE_SEMA + 1)
49 
50 struct i915_pmu_sample {
51 	u64 cur;
52 };
53 
54 struct i915_pmu {
55 	/**
56 	 * @cpuhp: Struct used for CPU hotplug handling.
57 	 */
58 	struct {
59 		struct hlist_node node;
60 		unsigned int cpu;
61 	} cpuhp;
62 	/**
63 	 * @base: PMU base.
64 	 */
65 	struct pmu base;
66 	/**
67 	 * @closed: i915 is unregistering.
68 	 */
69 	bool closed;
70 	/**
71 	 * @name: Name as registered with perf core.
72 	 */
73 	const char *name;
74 	/**
75 	 * @lock: Lock protecting enable mask and ref count handling.
76 	 */
77 	spinlock_t lock;
78 	/**
79 	 * @timer: Timer for internal i915 PMU sampling.
80 	 */
81 	struct hrtimer timer;
82 	/**
83 	 * @enable: Bitmask of specific enabled events.
84 	 *
85 	 * For some events we need to track their state and do some internal
86 	 * house keeping.
87 	 *
88 	 * Each engine event sampler type and event listed in enum
89 	 * i915_pmu_tracked_events gets a bit in this field.
90 	 *
91 	 * Low bits are engine samplers and other events continue from there.
92 	 */
93 	u32 enable;
94 
95 	/**
96 	 * @timer_last:
97 	 *
98 	 * Timestmap of the previous timer invocation.
99 	 */
100 	ktime_t timer_last;
101 
102 	/**
103 	 * @enable_count: Reference counts for the enabled events.
104 	 *
105 	 * Array indices are mapped in the same way as bits in the @enable field
106 	 * and they are used to control sampling on/off when multiple clients
107 	 * are using the PMU API.
108 	 */
109 	unsigned int enable_count[I915_PMU_MASK_BITS];
110 	/**
111 	 * @timer_enabled: Should the internal sampling timer be running.
112 	 */
113 	bool timer_enabled;
114 	/**
115 	 * @sample: Current and previous (raw) counters for sampling events.
116 	 *
117 	 * These counters are updated from the i915 PMU sampling timer.
118 	 *
119 	 * Only global counters are held here, while the per-engine ones are in
120 	 * struct intel_engine_cs.
121 	 */
122 	struct i915_pmu_sample sample[__I915_NUM_PMU_SAMPLERS];
123 	/**
124 	 * @sleep_last: Last time GT parked for RC6 estimation.
125 	 */
126 	ktime_t sleep_last;
127 	/**
128 	 * @irq_count: Number of interrupts
129 	 *
130 	 * Intentionally unsigned long to avoid atomics or heuristics on 32bit.
131 	 * 4e9 interrupts are a lot and postprocessing can really deal with an
132 	 * occasional wraparound easily. It's 32bit after all.
133 	 */
134 	unsigned long irq_count;
135 	/**
136 	 * @events_attr_group: Device events attribute group.
137 	 */
138 	struct attribute_group events_attr_group;
139 	/**
140 	 * @i915_attr: Memory block holding device attributes.
141 	 */
142 	void *i915_attr;
143 	/**
144 	 * @pmu_attr: Memory block holding device attributes.
145 	 */
146 	void *pmu_attr;
147 };
148 
149 #ifdef CONFIG_PERF_EVENTS
150 int i915_pmu_init(void);
151 void i915_pmu_exit(void);
152 void i915_pmu_register(struct drm_i915_private *i915);
153 void i915_pmu_unregister(struct drm_i915_private *i915);
154 void i915_pmu_gt_parked(struct drm_i915_private *i915);
155 void i915_pmu_gt_unparked(struct drm_i915_private *i915);
156 #else
157 static inline int i915_pmu_init(void) { return 0; }
158 static inline void i915_pmu_exit(void) {}
159 static inline void i915_pmu_register(struct drm_i915_private *i915) {}
160 static inline void i915_pmu_unregister(struct drm_i915_private *i915) {}
161 static inline void i915_pmu_gt_parked(struct drm_i915_private *i915) {}
162 static inline void i915_pmu_gt_unparked(struct drm_i915_private *i915) {}
163 #endif
164 
165 #endif
166