1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21/*
22 * Copyright (c) 2009, Intel Corporation.
23 * All rights reserved.
24 */
25
26#ifndef _SYS_CPU_EVENT_H
27#define	_SYS_CPU_EVENT_H
28#include <sys/types.h>
29
30#ifdef	__cplusplus
31extern "C" {
32#endif
33
34#ifdef	_KERNEL
35
36/*
37 * CPU idle notification callbacks are divided into three priority classes:
38 *      1. Statically assigned high priority callbacks.
39 *      2. Dynamically allocated normal priority callbacks.
40 *      3. Statically assigned low priority callbacks.
41 *
42 * All registered callbacks will be called in priority order from high
43 * to low just before CPU enters hardware idle state and from low to
44 * high just after CPU wakes from idle state.
45 *
46 * The high and low priority classes are designed to support hardware
47 * ordering requirements. A dynamically assigned priority allows the
48 * framework to choose the order in which the callback is processed.
49 * If a callback has no dependency on other callbacks, it should use
50 * dynamic priority to avoid priority conflicts.
51 *
52 * Note that the priority doesn't describe how important a callback
53 * is, but just the order in which they are processed.  If a callback
54 * needs processing early in the idle notification cycle, it should
55 * have a higher priority.  If it needs to be at the end, or early on
56 * the exit, then it should have a lower priority.
57 */
58
59#define	CPU_IDLE_CB_PRIO_LOW_BASE	0x20000000U
60#define	CPU_IDLE_CB_PRIO_DYN_BASE	0x40000000U
61#define	CPU_IDLE_CB_PRIO_HIGH_BASE	0x40000001U
62#define	CPU_IDLE_CB_PRIO_RESV_BASE	0x80000000U
63
64/*
65 * Indicating dynamic priority to cpu_idle_{un}register_callback().
66 */
67#define	CPU_IDLE_CB_PRIO_DYNAMIC	CPU_IDLE_CB_PRIO_DYN_BASE
68/* Priority assigned to dtrace probe callback. */
69#define	CPU_IDLE_CB_PRIO_DTRACE		(CPU_IDLE_CB_PRIO_LOW_BASE + 0xC000000)
70
71
72#ifdef	__x86
73/* Priority assigned to TLB flush callback. */
74#define	CPU_IDLE_CB_PRIO_TLB		(CPU_IDLE_CB_PRIO_LOW_BASE + 0x100000)
75#endif
76
77/* Name of properties supported by CPU idle notification. */
78#define	CPU_IDLE_PROP_IDLE_STATE	"idle-state"
79#define	CPU_IDLE_PROP_ENTER_TIMESTAMP	"enter-ts"
80#define	CPU_IDLE_PROP_EXIT_TIMESTAMP	"exit-ts"
81#define	CPU_IDLE_PROP_LAST_IDLE_TIME	"last-idle-time"
82#define	CPU_IDLE_PROP_LAST_BUSY_TIME	"last-busy-time"
83#define	CPU_IDLE_PROP_TOTAL_IDLE_TIME	"total-idle-time"
84#define	CPU_IDLE_PROP_TOTAL_BUSY_TIME	"total-busy-time"
85#define	CPU_IDLE_PROP_INTERRUPT_COUNT	"interupt-count"
86
87/*
88 * sizeof(cpu_idle_prop_value_t) should be power of 2 to align on cache line.
89 */
90typedef union cpu_idle_prop_value {
91	intptr_t			cipv_intptr;
92	uint32_t			cipv_uint32;
93	uint64_t			cipv_uint64;
94	hrtime_t			cipv_hrtime;
95} cpu_idle_prop_value_t;
96
97typedef enum cpu_idle_prop_type {
98	CPU_IDLE_PROP_TYPE_INTPTR,
99	CPU_IDLE_PROP_TYPE_UINT32,
100	CPU_IDLE_PROP_TYPE_UINT64,
101	CPU_IDLE_PROP_TYPE_HRTIME,
102} cpu_idle_prop_type_t;
103
104typedef void *cpu_idle_callback_handle_t;
105typedef void *cpu_idle_callback_context_t;
106typedef void *cpu_idle_prop_handle_t;
107
108/*
109 * Function prototype for checking CPU wakeup events.
110 * If CPU has already been awakened, check_wakeup callback should call
111 * cpu_idle_exit() to notify CPU idle framework if it has been called yet.
112 */
113typedef void (* cpu_idle_check_wakeup_t)(void *arg);
114
115/*
116 * Function prototype for entering idle state notification callback.
117 * Callback for entering idle state notification must obey all constraints
118 * which apply to idle thread because it will be called in idle thread context.
119 * The callback will be called with interrupt disabled. The callback may enable
120 * interrupt if it can cooperate with corresponding idle_exit callback to
121 * handle interrupt happening after enabling interrupt. If idle_enter callback
122 * enables interrupt, the corresponding idle_exit callback may be called before
123 * returning from idle_enter callback.
124 */
125typedef void (* cpu_idle_enter_cbfn_t)(void *arg,
126    cpu_idle_callback_context_t ctx,
127    cpu_idle_check_wakeup_t check_func, void *check_arg);
128
129/*
130 * Function prototype for exiting idle state notification callback.
131 * Callback for exiting idle state notification will be called in idle thread
132 * context or interrupt context with interrupt disabled.
133 * There is a flag to distinguish the calling context.
134 * The callback must not try to enable interrupts.
135 */
136typedef void (* cpu_idle_exit_cbfn_t)(void *arg,
137    cpu_idle_callback_context_t ctx, int flag);
138
139#define	CPU_IDLE_CB_FLAG_INTR	0x1	/* Called in interrupt context. */
140#define	CPU_IDLE_CB_FLAG_IDLE	0x2	/* Called in idle thread context. */
141
142typedef struct cpu_idle_callback {
143	int				version;
144	cpu_idle_enter_cbfn_t		idle_enter;
145	cpu_idle_exit_cbfn_t		idle_exit;
146} cpu_idle_callback_t;
147
148#define	CPU_IDLE_CALLBACK_VER0		0
149#define	CPU_IDLE_CALLBACK_VERS		CPU_IDLE_CALLBACK_VER0
150
151/*
152 * Register a callback to be called when CPU idle state changes.
153 * All registered callbacks will be called in priority order from high to low
154 * when CPU enters idle state and from low to high when CPU leaves idle state.
155 * If CPU is predicted to sleep for a short time or be under heavy load,
156 * framework may skip calling registered callbacks when idle state changes to
157 * avoid overhead and reduce performance penalties.
158 * It's guaranteed that each exiting notification will be paired with each
159 * entering notification.
160 * Return zero on success and error code on failure.
161 * N.B.: this interface shouldn't be called from following conditions:
162 *       1) from callback.
163 */
164extern int cpu_idle_register_callback(uint_t prio, cpu_idle_callback_t *cbp,
165    void *arg, cpu_idle_callback_handle_t *hdlp);
166
167/*
168 * Un-register a registered callback.
169 * Return zero on success and error code on failure.
170 * N.B.: this interface shouldn't be called from following cases:
171 *       1) from callback.
172 */
173extern int cpu_idle_unregister_callback(cpu_idle_callback_handle_t hdl);
174
175/*
176 * Called by CPU idle handler to notify entering idle state.
177 * It should be called with interrupt disabled.
178 * state: platform specific information of idle state to enter.
179 *        On x86, it's CPU C state.
180 * Idle thread should cancel entering hardware idle state if cpu_idle_enter
181 * returns non-zero value.
182 */
183extern int cpu_idle_enter(int state, int flag,
184    cpu_idle_check_wakeup_t check_func, void *check_arg);
185
186/*
187 * Called by CPU idle handler to notify exiting idle state.
188 * It should be called with interrupt disabled.
189 */
190extern void cpu_idle_exit(int flag);
191
192/*
193 * Get CPU idle notification context corresponding to current CPU.
194 */
195extern cpu_idle_callback_context_t cpu_idle_get_context(void);
196
197/*
198 * Prototype of function called to update property value on demand.
199 * The callback should update property value corresponding to current CPU.
200 */
201typedef int (* cpu_idle_prop_update_t)(void *arg, uint64_t seqnum,
202    cpu_idle_prop_value_t *valp);
203
204/*
205 * Create a property with name and type.
206 * If parameter update is not NULL, it will be called on demand to update
207 * value of property corresponding to current CPU.
208 * If parameter update is NULL, provider should call cpu_idle_property_set
209 * to update property value for each CPU.
210 * Return zero on success with handle stored in hdlp, otherwise error code.
211 */
212extern int cpu_idle_prop_create_property(const char *name,
213    cpu_idle_prop_type_t type, cpu_idle_prop_update_t update, void *arg,
214    cpu_idle_prop_handle_t *hdlp);
215
216/*
217 * Destroy property corresponding to hdl.
218 * Return zero on success, otherwise error code.
219 */
220extern int cpu_idle_prop_destroy_property(cpu_idle_prop_handle_t hdl);
221
222/*
223 * Create handle for property with name 'name'.
224 * Return zero on success with handle stored in hdlp, otherwise error code.
225 */
226extern int cpu_idle_prop_create_handle(const char *name,
227    cpu_idle_prop_handle_t *hdlp);
228
229/*
230 * Destroy property handle.
231 * Return zero on success, otherwise error code.
232 */
233extern int cpu_idle_prop_destroy_handle(cpu_idle_prop_handle_t hdl);
234
235/*
236 * CPU idle property manipulation functions.
237 * All cpu_idle_prop_get/set_xxx functions with argument ctx should only be used
238 * to manipulate properties associated with current CPU.
239 * Context ctx shouldn't be passed to other CPUs to manipulate properties.
240 */
241extern cpu_idle_prop_type_t cpu_idle_prop_get_type(cpu_idle_prop_handle_t hdl);
242extern const char *cpu_idle_prop_get_name(cpu_idle_prop_handle_t hdl);
243extern int cpu_idle_prop_get_value(cpu_idle_prop_handle_t hdl,
244    cpu_idle_callback_context_t ctx, cpu_idle_prop_value_t *valp);
245extern uint32_t cpu_idle_prop_get_uint32(cpu_idle_prop_handle_t hdl,
246    cpu_idle_callback_context_t ctx);
247extern uint64_t cpu_idle_prop_get_uint64(cpu_idle_prop_handle_t hdl,
248    cpu_idle_callback_context_t ctx);
249extern intptr_t cpu_idle_prop_get_intptr(cpu_idle_prop_handle_t hdl,
250    cpu_idle_callback_context_t ctx);
251extern hrtime_t cpu_idle_prop_get_hrtime(cpu_idle_prop_handle_t hdl,
252    cpu_idle_callback_context_t ctx);
253extern void cpu_idle_prop_set_value(cpu_idle_prop_handle_t hdl,
254    cpu_idle_callback_context_t ctx, cpu_idle_prop_value_t val);
255extern void cpu_idle_prop_set_all(cpu_idle_prop_handle_t hdl,
256    cpu_idle_prop_value_t val);
257
258extern uint_t cpu_idle_get_cpu_state(cpu_t *cp);
259
260extern void cpu_event_init(void);
261extern void cpu_event_init_cpu(cpu_t *cp);
262extern void cpu_event_fini_cpu(cpu_t *cp);
263
264#endif	/* _KERNEL */
265
266#ifdef	__cplusplus
267}
268#endif
269
270#endif	/* _SYS_CPU_EVENT_H */
271