usr/src/uts/common/sys/cpudrv.h

   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 */