xref: /illumos-gate/usr/src/uts/common/sys/cpudrv.h (revision 726fad2a65f16c200a03969c29cb5c86c2d427db)
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 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 /*
26  * Copyright (c) 2009,  Intel Corporation.
27  * All Rights Reserved.
28  */
29 
30 #ifndef _SYS_CPUDRV_H
31 #define	_SYS_CPUDRV_H
32 
33 #include <sys/promif.h>
34 #include <sys/cpuvar.h>
35 #include <sys/taskq.h>
36 
37 #ifdef	__cplusplus
38 extern "C" {
39 #endif
40 
41 #ifdef _KERNEL
42 
43 /*
44  * CPU power management data
45  */
46 /*
47  * Data related to a particular speed.
48  *
49  * All per speed data nodes for a CPU are linked together using down_spd.
50  * The link list is ordered with first node containing data for
51  * normal (maximum) speed. up_spd points to the next speed up. Currently
52  * all up_spd's point to the normal speed but this can be changed in future.
53  * quant_cnt is the number of ticks when monitoring system will be called
54  * next. There are different quant_cnt for different speeds.
55  *
56  * Note that 'speed' has different meaning depending upon the platform.
57  * On SPARC, the speed is really a divisor of the maximum speed (e.g., a speed
58  * of 2 means that it's 1/2 the maximum speed). On x86, speed is a processor
59  * frequency.
60  */
61 typedef struct cpudrv_pm_spd {
62 	uint_t			speed;		/* platform dependent notion */
63 	uint_t			quant_cnt;	/* quantum count in ticks */
64 	struct cpudrv_pm_spd	*down_spd;	/* ptr to next speed down */
65 	struct cpudrv_pm_spd	*up_spd;	/* ptr to next speed up */
66 	uint_t			idle_hwm;	/* down if idle thread >= hwm */
67 	uint_t			idle_lwm;	/* up if idle thread < lwm */
68 	uint_t			idle_bhwm_cnt;	/* # of iters idle is < hwm */
69 	uint_t			idle_blwm_cnt;	/* # of iters idle is < lwm */
70 	uint_t			user_hwm;	/* up if user thread > hwm */
71 	int			user_lwm;	/* down if user thread <= lwm */
72 	int			pm_level;	/* power level for framework */
73 } cpudrv_pm_spd_t;
74 
75 /*
76  * Power management data
77  */
78 typedef struct cpudrv_pm {
79 	cpudrv_pm_spd_t	*head_spd;	/* ptr to head of speed */
80 	cpudrv_pm_spd_t	*cur_spd;	/* ptr to current speed */
81 	uint_t		num_spd;	/* number of speeds */
82 	hrtime_t	lastquan_mstate[NCMSTATES]; /* last quantum's mstate */
83 	clock_t		lastquan_ticks;	/* last quantum's clock tick */
84 	int		pm_busycnt;	/* pm_busy_component() count  */
85 	ddi_taskq_t	*tq;		/* taskq handler for CPU monitor */
86 	timeout_id_t	timeout_id;	/* cpudrv_monitor()'s timeout_id */
87 	int		timeout_count;	/* count dispatched timeouts */
88 	kmutex_t	timeout_lock;	/* protect timeout_count */
89 	kcondvar_t	timeout_cv;	/* wait on timeout_count change */
90 #if defined(__x86)
91 	kthread_t	*pm_governor_thread; /* governor thread */
92 	cpudrv_pm_spd_t	*top_spd;	/* ptr to effective head speed */
93 #endif
94 	boolean_t	pm_started;	/* PM really started */
95 } cpudrv_pm_t;
96 
97 /*
98  * Idle & user threads water marks in percentage
99  */
100 #if defined(__x86)
101 #define	CPUDRV_IDLE_HWM		85	/* idle high water mark */
102 #define	CPUDRV_IDLE_LWM		70	/* idle low water mark */
103 #define	CPUDRV_IDLE_BLWM_CNT_MAX	1    /* # of iters idle can be < lwm */
104 #define	CPUDRV_IDLE_BHWM_CNT_MAX	1    /* # of iters idle can be < hwm */
105 #else
106 #define	CPUDRV_IDLE_HWM		98	/* idle high water mark */
107 #define	CPUDRV_IDLE_LWM		8	/* idle low water mark */
108 #define	CPUDRV_IDLE_BLWM_CNT_MAX	2    /* # of iters idle can be < lwm */
109 #define	CPUDRV_IDLE_BHWM_CNT_MAX	2    /* # of iters idle can be < hwm */
110 #endif
111 #define	CPUDRV_USER_HWM		20	/* user high water mark */
112 #define	CPUDRV_IDLE_BUF_ZONE		4    /* buffer zone when going down */
113 
114 
115 /*
116  * Maximums for creating 'pm-components' property
117  */
118 #define	CPUDRV_COMP_MAX_DIG	4	/* max digits in power level */
119 					/* or divisor */
120 #define	CPUDRV_COMP_MAX_VAL	9999	/* max value in above digits */
121 
122 /*
123  * Component number for calls to PM framework
124  */
125 #define	CPUDRV_COMP_NUM	0	/* first component is 0 */
126 
127 /*
128  * Quantum counts for normal and other clock speeds in terms of ticks.
129  *
130  * In determining the quantum count, we need to balance two opposing factors:
131  *
132  *	1) Minimal delay when user start using the CPU that is in low
133  *	power mode -- requires that we monitor more frequently,
134  *
135  *	2) Extra code executed because of frequent monitoring -- requires
136  *	that we monitor less frequently.
137  *
138  * We reach a tradeoff between these two requirements by monitoring
139  * more frequently when we are in low speed mode (CPUDRV_QUANT_CNT_OTHR)
140  * so we can bring the CPU up without user noticing it. Moreover, at low
141  * speed we are not using CPU much so extra code execution should be fine.
142  * Since we are in no hurry to bring CPU down and at normal speed and we
143  * might really be using the CPU fully, we monitor less frequently
144  * (CPUDRV_QUANT_CNT_NORMAL).
145  */
146 #if defined(__x86)
147 #define	CPUDRV_QUANT_CNT_NORMAL	(hz * 1)	/* 1 sec */
148 #else
149 #define	CPUDRV_QUANT_CNT_NORMAL	(hz * 5)	/* 5 sec */
150 #endif
151 #define	CPUDRV_QUANT_CNT_OTHR	(hz * 1)	/* 1 sec */
152 
153 /*
154  * Taskq parameters
155  */
156 #define	CPUDRV_TASKQ_THREADS		1    /* # threads to run CPU monitor */
157 #define	CPUDRV_TASKQ_MIN		2	/* min # of taskq entries */
158 #define	CPUDRV_TASKQ_MAX		2	/* max # of taskq entries */
159 
160 
161 /*
162  * Device driver state structure
163  */
164 typedef struct cpudrv_devstate {
165 	dev_info_t	*dip;		/* devinfo handle */
166 	cpu_t		*cp;		/* CPU data for this node */
167 	processorid_t	cpu_id;		/* CPU number for this node */
168 	cpudrv_pm_t	cpudrv_pm;	/* power management data */
169 	kmutex_t	lock;		/* protects state struct */
170 } cpudrv_devstate_t;
171 
172 extern void	*cpudrv_state;
173 extern boolean_t cpudrv_enabled;
174 
175 /*
176  * Debugging definitions
177  */
178 #ifdef	DEBUG
179 #define	D_INIT			0x00000001
180 #define	D_FINI			0x00000002
181 #define	D_ATTACH		0x00000004
182 #define	D_DETACH		0x00000008
183 #define	D_POWER			0x00000010
184 #define	D_PM_INIT		0x00000020
185 #define	D_PM_FREE		0x00000040
186 #define	D_PM_COMP_CREATE	0x00000080
187 #define	D_PM_MONITOR		0x00000100
188 #define	D_PM_MONITOR_VERBOSE	0x00000200
189 #define	D_PM_MONITOR_DELAY	0x00000400
190 
191 extern uint_t	cpudrv_debug;
192 
193 #define	_PRINTF prom_printf
194 #define	DPRINTF(flag, args)	if (cpudrv_debug & flag) _PRINTF args;
195 #else
196 #define	DPRINTF(flag, args)
197 #endif /* DEBUG */
198 
199 extern int cpudrv_change_speed(cpudrv_devstate_t *, cpudrv_pm_spd_t *);
200 extern boolean_t cpudrv_get_cpu_id(dev_info_t *, processorid_t *);
201 extern boolean_t cpudrv_is_governor_thread(cpudrv_pm_t *);
202 extern boolean_t cpudrv_mach_init(cpudrv_devstate_t *);
203 extern boolean_t cpudrv_mach_fini(cpudrv_devstate_t *);
204 extern boolean_t cpudrv_power_ready(cpu_t *);
205 extern boolean_t cpudrv_is_enabled(cpudrv_devstate_t *);
206 extern void cpudrv_set_supp_freqs(cpudrv_devstate_t *);
207 extern int cpudrv_get_cpu(cpudrv_devstate_t *);
208 
209 #endif /* _KERNEL */
210 
211 #ifdef	__cplusplus
212 }
213 #endif
214 
215 #endif /* _SYS_CPUDRV_H */
216