/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2009 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ /* * Copyright (c) 2009, Intel Corporation. * All Rights Reserved. */ /* * CPU Device driver. The driver is not DDI-compliant. * * The driver supports following features: * - Power management. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * CPU power management * * The supported power saving model is to slow down the CPU (on SPARC by * dividing the CPU clock and on x86 by dropping down a P-state). * Periodically we determine the amount of time the CPU is running * idle thread and threads in user mode during the last quantum. If the idle * thread was running less than its low water mark for current speed for * number of consecutive sampling periods, or number of running threads in * user mode are above its high water mark, we arrange to go to the higher * speed. If the idle thread was running more than its high water mark without * dropping a number of consecutive times below the mark, and number of threads * running in user mode are below its low water mark, we arrange to go to the * next lower speed. While going down, we go through all the speeds. While * going up we go to the maximum speed to minimize impact on the user, but have * provisions in the driver to go to other speeds. * * The driver does not have knowledge of a particular implementation of this * scheme and will work with all CPUs supporting this model. On SPARC, the * driver determines supported speeds by looking at 'clock-divisors' property * created by OBP. On x86, the driver retrieves the supported speeds from * ACPI. */ /* * Configuration function prototypes and data structures */ static int cpudrv_attach(dev_info_t *dip, ddi_attach_cmd_t cmd); static int cpudrv_detach(dev_info_t *dip, ddi_detach_cmd_t cmd); static int cpudrv_power(dev_info_t *dip, int comp, int level); struct dev_ops cpudrv_ops = { DEVO_REV, /* rev */ 0, /* refcnt */ nodev, /* getinfo */ nulldev, /* identify */ nulldev, /* probe */ cpudrv_attach, /* attach */ cpudrv_detach, /* detach */ nodev, /* reset */ (struct cb_ops *)NULL, /* cb_ops */ (struct bus_ops *)NULL, /* bus_ops */ cpudrv_power, /* power */ ddi_quiesce_not_needed, /* quiesce */ }; static struct modldrv modldrv = { &mod_driverops, /* modops */ "CPU Driver", /* linkinfo */ &cpudrv_ops, /* dev_ops */ }; static struct modlinkage modlinkage = { MODREV_1, /* rev */ &modldrv, /* linkage */ NULL }; /* * Function prototypes */ static int cpudrv_init(cpudrv_devstate_t *cpudsp); static void cpudrv_free(cpudrv_devstate_t *cpudsp); static int cpudrv_comp_create(cpudrv_devstate_t *cpudsp); static void cpudrv_monitor_disp(void *arg); static void cpudrv_monitor(void *arg); /* * Driver global variables */ uint_t cpudrv_debug = 0; void *cpudrv_state; static uint_t cpudrv_idle_hwm = CPUDRV_IDLE_HWM; static uint_t cpudrv_idle_lwm = CPUDRV_IDLE_LWM; static uint_t cpudrv_idle_buf_zone = CPUDRV_IDLE_BUF_ZONE; static uint_t cpudrv_idle_bhwm_cnt_max = CPUDRV_IDLE_BHWM_CNT_MAX; static uint_t cpudrv_idle_blwm_cnt_max = CPUDRV_IDLE_BLWM_CNT_MAX; static uint_t cpudrv_user_hwm = CPUDRV_USER_HWM; boolean_t cpudrv_enabled = B_TRUE; /* * cpudrv_direct_pm allows user applications to directly control the * power state transitions (direct pm) without following the normal * direct pm protocol. This is needed because the normal protocol * requires that a device only be lowered when it is idle, and be * brought up when it request to do so by calling pm_raise_power(). * Ignoring this protocol is harmless for CPU (other than speed). * Moreover it might be the case that CPU is never idle or wants * to be at higher speed because of the addition CPU cycles required * to run the user application. * * The driver will still report idle/busy status to the framework. Although * framework will ignore this information for direct pm devices and not * try to bring them down when idle, user applications can still use this * information if they wants. * * In the future, provide an ioctl to control setting of this mode. In * that case, this variable should move to the state structure and * be protected by the lock in the state structure. */ int cpudrv_direct_pm = 0; /* * Arranges for the handler function to be called at the interval suitable * for current speed. */ #define CPUDRV_MONITOR_INIT(cpudsp) { \ if (cpudrv_is_enabled(cpudsp)) { \ ASSERT(mutex_owned(&(cpudsp)->lock)); \ (cpudsp)->cpudrv_pm.timeout_id = \ timeout(cpudrv_monitor_disp, \ (cpudsp), (((cpudsp)->cpudrv_pm.cur_spd == NULL) ? \ CPUDRV_QUANT_CNT_OTHR : \ (cpudsp)->cpudrv_pm.cur_spd->quant_cnt)); \ } \ } /* * Arranges for the handler function not to be called back. */ #define CPUDRV_MONITOR_FINI(cpudsp) { \ timeout_id_t tmp_tid; \ ASSERT(mutex_owned(&(cpudsp)->lock)); \ tmp_tid = (cpudsp)->cpudrv_pm.timeout_id; \ (cpudsp)->cpudrv_pm.timeout_id = 0; \ mutex_exit(&(cpudsp)->lock); \ if (tmp_tid != 0) { \ (void) untimeout(tmp_tid); \ mutex_enter(&(cpudsp)->cpudrv_pm.timeout_lock); \ while ((cpudsp)->cpudrv_pm.timeout_count != 0) \ cv_wait(&(cpudsp)->cpudrv_pm.timeout_cv, \ &(cpudsp)->cpudrv_pm.timeout_lock); \ mutex_exit(&(cpudsp)->cpudrv_pm.timeout_lock); \ } \ mutex_enter(&(cpudsp)->lock); \ } int _init(void) { int error; DPRINTF(D_INIT, (" _init: function called\n")); if ((error = ddi_soft_state_init(&cpudrv_state, sizeof (cpudrv_devstate_t), 0)) != 0) { return (error); } if ((error = mod_install(&modlinkage)) != 0) { ddi_soft_state_fini(&cpudrv_state); } /* * Callbacks used by the PPM driver. */ CPUDRV_SET_PPM_CALLBACKS(); return (error); } int _fini(void) { int error; DPRINTF(D_FINI, (" _fini: function called\n")); if ((error = mod_remove(&modlinkage)) == 0) { ddi_soft_state_fini(&cpudrv_state); } return (error); } int _info(struct modinfo *modinfop) { return (mod_info(&modlinkage, modinfop)); } /* * Driver attach(9e) entry point. */ static int cpudrv_attach(dev_info_t *dip, ddi_attach_cmd_t cmd) { int instance; cpudrv_devstate_t *cpudsp; instance = ddi_get_instance(dip); switch (cmd) { case DDI_ATTACH: DPRINTF(D_ATTACH, ("cpudrv_attach: instance %d: " "DDI_ATTACH called\n", instance)); if (!cpudrv_is_enabled(NULL)) return (DDI_FAILURE); if (ddi_soft_state_zalloc(cpudrv_state, instance) != DDI_SUCCESS) { cmn_err(CE_WARN, "cpudrv_attach: instance %d: " "can't allocate state", instance); cpudrv_enabled = B_FALSE; return (DDI_FAILURE); } if ((cpudsp = ddi_get_soft_state(cpudrv_state, instance)) == NULL) { cmn_err(CE_WARN, "cpudrv_attach: instance %d: " "can't get state", instance); ddi_soft_state_free(cpudrv_state, instance); cpudrv_enabled = B_FALSE; return (DDI_FAILURE); } cpudsp->dip = dip; /* * Find CPU number for this dev_info node. */ if (!cpudrv_get_cpu_id(dip, &(cpudsp->cpu_id))) { cmn_err(CE_WARN, "cpudrv_attach: instance %d: " "can't convert dip to cpu_id", instance); ddi_soft_state_free(cpudrv_state, instance); cpudrv_enabled = B_FALSE; return (DDI_FAILURE); } mutex_init(&cpudsp->lock, NULL, MUTEX_DRIVER, NULL); if (cpudrv_is_enabled(cpudsp)) { if (cpudrv_init(cpudsp) != DDI_SUCCESS) { cpudrv_enabled = B_FALSE; cpudrv_free(cpudsp); ddi_soft_state_free(cpudrv_state, instance); return (DDI_FAILURE); } if (cpudrv_comp_create(cpudsp) != DDI_SUCCESS) { cpudrv_enabled = B_FALSE; cpudrv_free(cpudsp); ddi_soft_state_free(cpudrv_state, instance); return (DDI_FAILURE); } if (ddi_prop_update_string(DDI_DEV_T_NONE, dip, "pm-class", "CPU") != DDI_PROP_SUCCESS) { cpudrv_enabled = B_FALSE; cpudrv_free(cpudsp); ddi_soft_state_free(cpudrv_state, instance); return (DDI_FAILURE); } /* * Taskq is used to dispatch routine to monitor CPU * activities. */ cpudsp->cpudrv_pm.tq = ddi_taskq_create(dip, "cpudrv_monitor", CPUDRV_TASKQ_THREADS, TASKQ_DEFAULTPRI, 0); mutex_init(&cpudsp->cpudrv_pm.timeout_lock, NULL, MUTEX_DRIVER, NULL); cv_init(&cpudsp->cpudrv_pm.timeout_cv, NULL, CV_DEFAULT, NULL); /* * Driver needs to assume that CPU is running at * unknown speed at DDI_ATTACH and switch it to the * needed speed. We assume that initial needed speed * is full speed for us. */ /* * We need to take the lock because cpudrv_monitor() * will start running in parallel with attach(). */ mutex_enter(&cpudsp->lock); cpudsp->cpudrv_pm.cur_spd = NULL; cpudsp->cpudrv_pm.pm_started = B_FALSE; /* * We don't call pm_raise_power() directly from attach * because driver attach for a slave CPU node can * happen before the CPU is even initialized. We just * start the monitoring system which understands * unknown speed and moves CPU to top speed when it * has been initialized. */ CPUDRV_MONITOR_INIT(cpudsp); mutex_exit(&cpudsp->lock); } if (!cpudrv_mach_init(cpudsp)) { cmn_err(CE_WARN, "cpudrv_attach: instance %d: " "cpudrv_mach_init failed", instance); cpudrv_enabled = B_FALSE; cpudrv_free(cpudsp); ddi_soft_state_free(cpudrv_state, instance); return (DDI_FAILURE); } CPUDRV_INSTALL_MAX_CHANGE_HANDLER(cpudsp); (void) ddi_prop_update_int(DDI_DEV_T_NONE, dip, DDI_NO_AUTODETACH, 1); ddi_report_dev(dip); return (DDI_SUCCESS); case DDI_RESUME: DPRINTF(D_ATTACH, ("cpudrv_attach: instance %d: " "DDI_RESUME called\n", instance)); cpudsp = ddi_get_soft_state(cpudrv_state, instance); ASSERT(cpudsp != NULL); /* * Nothing to do for resume, if not doing active PM. */ if (!cpudrv_is_enabled(cpudsp)) return (DDI_SUCCESS); mutex_enter(&cpudsp->lock); /* * Driver needs to assume that CPU is running at unknown speed * at DDI_RESUME and switch it to the needed speed. We assume * that the needed speed is full speed for us. */ cpudsp->cpudrv_pm.cur_spd = NULL; CPUDRV_MONITOR_INIT(cpudsp); mutex_exit(&cpudsp->lock); CPUDRV_REDEFINE_TOPSPEED(dip); return (DDI_SUCCESS); default: return (DDI_FAILURE); } } /* * Driver detach(9e) entry point. */ static int cpudrv_detach(dev_info_t *dip, ddi_detach_cmd_t cmd) { int instance; cpudrv_devstate_t *cpudsp; cpudrv_pm_t *cpupm; instance = ddi_get_instance(dip); switch (cmd) { case DDI_DETACH: DPRINTF(D_DETACH, ("cpudrv_detach: instance %d: " "DDI_DETACH called\n", instance)); #if defined(__x86) cpudsp = ddi_get_soft_state(cpudrv_state, instance); ASSERT(cpudsp != NULL); /* * Nothing to do for detach, if no doing active PM. */ if (!cpudrv_is_enabled(cpudsp)) return (DDI_SUCCESS); /* * uninstall PPC/_TPC change notification handler */ CPUDRV_UNINSTALL_MAX_CHANGE_HANDLER(cpudsp); /* * destruct platform specific resource */ if (!cpudrv_mach_fini(cpudsp)) return (DDI_FAILURE); mutex_enter(&cpudsp->lock); CPUDRV_MONITOR_FINI(cpudsp); cv_destroy(&cpudsp->cpudrv_pm.timeout_cv); mutex_destroy(&cpudsp->cpudrv_pm.timeout_lock); ddi_taskq_destroy(cpudsp->cpudrv_pm.tq); cpudrv_free(cpudsp); mutex_exit(&cpudsp->lock); mutex_destroy(&cpudsp->lock); ddi_soft_state_free(cpudrv_state, instance); (void) ddi_prop_update_int(DDI_DEV_T_NONE, dip, DDI_NO_AUTODETACH, 0); return (DDI_SUCCESS); #else /* * If the only thing supported by the driver is power * management, we can in future enhance the driver and * framework that loads it to unload the driver when * user has disabled CPU power management. */ return (DDI_FAILURE); #endif case DDI_SUSPEND: DPRINTF(D_DETACH, ("cpudrv_detach: instance %d: " "DDI_SUSPEND called\n", instance)); cpudsp = ddi_get_soft_state(cpudrv_state, instance); ASSERT(cpudsp != NULL); /* * Nothing to do for suspend, if not doing active PM. */ if (!cpudrv_is_enabled(cpudsp)) return (DDI_SUCCESS); /* * During a checkpoint-resume sequence, framework will * stop interrupts to quiesce kernel activity. This will * leave our monitoring system ineffective. Handle this * by stopping our monitoring system and bringing CPU * to full speed. In case we are in special direct pm * mode, we leave the CPU at whatever speed it is. This * is harmless other than speed. */ mutex_enter(&cpudsp->lock); cpupm = &(cpudsp->cpudrv_pm); DPRINTF(D_DETACH, ("cpudrv_detach: instance %d: DDI_SUSPEND - " "cur_spd %d, topspeed %d\n", instance, cpupm->cur_spd->pm_level, CPUDRV_TOPSPEED(cpupm)->pm_level)); CPUDRV_MONITOR_FINI(cpudsp); if (!cpudrv_direct_pm && (cpupm->cur_spd != CPUDRV_TOPSPEED(cpupm))) { if (cpupm->pm_busycnt < 1) { if ((pm_busy_component(dip, CPUDRV_COMP_NUM) == DDI_SUCCESS)) { cpupm->pm_busycnt++; } else { CPUDRV_MONITOR_INIT(cpudsp); mutex_exit(&cpudsp->lock); cmn_err(CE_WARN, "cpudrv_detach: " "instance %d: can't busy CPU " "component", instance); return (DDI_FAILURE); } } mutex_exit(&cpudsp->lock); if (pm_raise_power(dip, CPUDRV_COMP_NUM, CPUDRV_TOPSPEED(cpupm)->pm_level) != DDI_SUCCESS) { mutex_enter(&cpudsp->lock); CPUDRV_MONITOR_INIT(cpudsp); mutex_exit(&cpudsp->lock); cmn_err(CE_WARN, "cpudrv_detach: instance %d: " "can't raise CPU power level to %d", instance, CPUDRV_TOPSPEED(cpupm)->pm_level); return (DDI_FAILURE); } else { return (DDI_SUCCESS); } } else { mutex_exit(&cpudsp->lock); return (DDI_SUCCESS); } default: return (DDI_FAILURE); } } /* * Driver power(9e) entry point. * * Driver's notion of current power is set *only* in power(9e) entry point * after actual power change operation has been successfully completed. */ /* ARGSUSED */ static int cpudrv_power(dev_info_t *dip, int comp, int level) { int instance; cpudrv_devstate_t *cpudsp; cpudrv_pm_t *cpudrvpm; cpudrv_pm_spd_t *new_spd; boolean_t is_ready; int ret; instance = ddi_get_instance(dip); DPRINTF(D_POWER, ("cpudrv_power: instance %d: level %d\n", instance, level)); if ((cpudsp = ddi_get_soft_state(cpudrv_state, instance)) == NULL) { cmn_err(CE_WARN, "cpudrv_power: instance %d: can't " "get state", instance); return (DDI_FAILURE); } /* * We're not ready until we can get a cpu_t */ is_ready = (cpudrv_get_cpu(cpudsp) == DDI_SUCCESS); mutex_enter(&cpudsp->lock); cpudrvpm = &(cpudsp->cpudrv_pm); /* * In normal operation, we fail if we are busy and request is * to lower the power level. We let this go through if the driver * is in special direct pm mode. On x86, we also let this through * if the change is due to a request to govern the max speed. */ if (!cpudrv_direct_pm && (cpudrvpm->pm_busycnt >= 1) && !cpudrv_is_governor_thread(cpudrvpm)) { if ((cpudrvpm->cur_spd != NULL) && (level < cpudrvpm->cur_spd->pm_level)) { mutex_exit(&cpudsp->lock); return (DDI_FAILURE); } } for (new_spd = cpudrvpm->head_spd; new_spd; new_spd = new_spd->down_spd) { if (new_spd->pm_level == level) break; } if (!new_spd) { CPUDRV_RESET_GOVERNOR_THREAD(cpudrvpm); mutex_exit(&cpudsp->lock); cmn_err(CE_WARN, "cpudrv_power: instance %d: " "can't locate new CPU speed", instance); return (DDI_FAILURE); } /* * We currently refuse to power manage if the CPU is not ready to * take cross calls (cross calls fail silently if CPU is not ready * for it). * * Additionally, for x86 platforms we cannot power manage an instance, * until it has been initialized. */ if (is_ready) { is_ready = CPUDRV_XCALL_IS_READY(cpudsp->cpu_id); if (!is_ready) { DPRINTF(D_POWER, ("cpudrv_power: instance %d: " "CPU not ready for x-calls\n", instance)); } else if (!(is_ready = cpudrv_power_ready(cpudsp->cp))) { DPRINTF(D_POWER, ("cpudrv_power: instance %d: " "waiting for all CPUs to be power manageable\n", instance)); } } if (!is_ready) { CPUDRV_RESET_GOVERNOR_THREAD(cpudrvpm); mutex_exit(&cpudsp->lock); return (DDI_FAILURE); } /* * Execute CPU specific routine on the requested CPU to * change its speed to normal-speed/divisor. */ if ((ret = cpudrv_change_speed(cpudsp, new_spd)) != DDI_SUCCESS) { cmn_err(CE_WARN, "cpudrv_power: " "cpudrv_change_speed() return = %d", ret); mutex_exit(&cpudsp->lock); return (DDI_FAILURE); } /* * Reset idle threshold time for the new power level. */ if ((cpudrvpm->cur_spd != NULL) && (level < cpudrvpm->cur_spd->pm_level)) { if (pm_idle_component(dip, CPUDRV_COMP_NUM) == DDI_SUCCESS) { if (cpudrvpm->pm_busycnt >= 1) cpudrvpm->pm_busycnt--; } else { cmn_err(CE_WARN, "cpudrv_power: instance %d: " "can't idle CPU component", ddi_get_instance(dip)); } } /* * Reset various parameters because we are now running at new speed. */ cpudrvpm->lastquan_mstate[CMS_IDLE] = 0; cpudrvpm->lastquan_mstate[CMS_SYSTEM] = 0; cpudrvpm->lastquan_mstate[CMS_USER] = 0; cpudrvpm->lastquan_ticks = 0; cpudrvpm->cur_spd = new_spd; CPUDRV_RESET_GOVERNOR_THREAD(cpudrvpm); mutex_exit(&cpudsp->lock); return (DDI_SUCCESS); } /* * Initialize power management data. */ static int cpudrv_init(cpudrv_devstate_t *cpudsp) { cpudrv_pm_t *cpupm = &(cpudsp->cpudrv_pm); cpudrv_pm_spd_t *cur_spd; cpudrv_pm_spd_t *prev_spd = NULL; int *speeds; uint_t nspeeds; int idle_cnt_percent; int user_cnt_percent; int i; CPUDRV_GET_SPEEDS(cpudsp, speeds, nspeeds); if (nspeeds < 2) { /* Need at least two speeds to power manage */ CPUDRV_FREE_SPEEDS(speeds, nspeeds); return (DDI_FAILURE); } cpupm->num_spd = nspeeds; /* * Calculate the watermarks and other parameters based on the * supplied speeds. * * One of the basic assumption is that for X amount of CPU work, * if CPU is slowed down by a factor of N, the time it takes to * do the same work will be N * X. * * The driver declares that a CPU is idle and ready for slowed down, * if amount of idle thread is more than the current speed idle_hwm * without dropping below idle_hwm a number of consecutive sampling * intervals and number of running threads in user mode are below * user_lwm. We want to set the current user_lwm such that if we * just switched to the next slower speed with no change in real work * load, the amount of user threads at the slower speed will be such * that it falls below the slower speed's user_hwm. If we didn't do * that then we will just come back to the higher speed as soon as we * go down even with no change in work load. * The user_hwm is a fixed precentage and not calculated dynamically. * * We bring the CPU up if idle thread at current speed is less than * the current speed idle_lwm for a number of consecutive sampling * intervals or user threads are above the user_hwm for the current * speed. */ for (i = 0; i < nspeeds; i++) { cur_spd = kmem_zalloc(sizeof (cpudrv_pm_spd_t), KM_SLEEP); cur_spd->speed = speeds[i]; if (i == 0) { /* normal speed */ cpupm->head_spd = cur_spd; CPUDRV_TOPSPEED(cpupm) = cur_spd; cur_spd->quant_cnt = CPUDRV_QUANT_CNT_NORMAL; cur_spd->idle_hwm = (cpudrv_idle_hwm * cur_spd->quant_cnt) / 100; /* can't speed anymore */ cur_spd->idle_lwm = 0; cur_spd->user_hwm = UINT_MAX; } else { cur_spd->quant_cnt = CPUDRV_QUANT_CNT_OTHR; ASSERT(prev_spd != NULL); prev_spd->down_spd = cur_spd; cur_spd->up_spd = cpupm->head_spd; /* * Let's assume CPU is considered idle at full speed * when it is spending I% of time in running the idle * thread. At full speed, CPU will be busy (100 - I) % * of times. This % of busyness increases by factor of * N as CPU slows down. CPU that is idle I% of times * in full speed, it is idle (100 - ((100 - I) * N)) % * of times in N speed. The idle_lwm is a fixed * percentage. A large value of N may result in * idle_hwm to go below idle_lwm. We need to make sure * that there is at least a buffer zone seperation * between the idle_lwm and idle_hwm values. */ idle_cnt_percent = CPUDRV_IDLE_CNT_PERCENT( cpudrv_idle_hwm, speeds, i); idle_cnt_percent = max(idle_cnt_percent, (cpudrv_idle_lwm + cpudrv_idle_buf_zone)); cur_spd->idle_hwm = (idle_cnt_percent * cur_spd->quant_cnt) / 100; cur_spd->idle_lwm = (cpudrv_idle_lwm * cur_spd->quant_cnt) / 100; /* * The lwm for user threads are determined such that * if CPU slows down, the load of work in the * new speed would still keep the CPU at or below the * user_hwm in the new speed. This is to prevent * the quick jump back up to higher speed. */ cur_spd->user_hwm = (cpudrv_user_hwm * cur_spd->quant_cnt) / 100; user_cnt_percent = CPUDRV_USER_CNT_PERCENT( cpudrv_user_hwm, speeds, i); prev_spd->user_lwm = (user_cnt_percent * prev_spd->quant_cnt) / 100; } prev_spd = cur_spd; } /* Slowest speed. Can't slow down anymore */ cur_spd->idle_hwm = UINT_MAX; cur_spd->user_lwm = -1; #ifdef DEBUG DPRINTF(D_PM_INIT, ("cpudrv_init: instance %d: head_spd spd %d, " "num_spd %d\n", ddi_get_instance(cpudsp->dip), cpupm->head_spd->speed, cpupm->num_spd)); for (cur_spd = cpupm->head_spd; cur_spd; cur_spd = cur_spd->down_spd) { DPRINTF(D_PM_INIT, ("cpudrv_init: instance %d: speed %d, " "down_spd spd %d, idle_hwm %d, user_lwm %d, " "up_spd spd %d, idle_lwm %d, user_hwm %d, " "quant_cnt %d\n", ddi_get_instance(cpudsp->dip), cur_spd->speed, (cur_spd->down_spd ? cur_spd->down_spd->speed : 0), cur_spd->idle_hwm, cur_spd->user_lwm, (cur_spd->up_spd ? cur_spd->up_spd->speed : 0), cur_spd->idle_lwm, cur_spd->user_hwm, cur_spd->quant_cnt)); } #endif /* DEBUG */ CPUDRV_FREE_SPEEDS(speeds, nspeeds); return (DDI_SUCCESS); } /* * Free CPU power management data. */ static void cpudrv_free(cpudrv_devstate_t *cpudsp) { cpudrv_pm_t *cpupm = &(cpudsp->cpudrv_pm); cpudrv_pm_spd_t *cur_spd, *next_spd; cur_spd = cpupm->head_spd; while (cur_spd) { next_spd = cur_spd->down_spd; kmem_free(cur_spd, sizeof (cpudrv_pm_spd_t)); cur_spd = next_spd; } bzero(cpupm, sizeof (cpudrv_pm_t)); } /* * Create pm-components property. */ static int cpudrv_comp_create(cpudrv_devstate_t *cpudsp) { cpudrv_pm_t *cpupm = &(cpudsp->cpudrv_pm); cpudrv_pm_spd_t *cur_spd; char **pmc; int size; char name[] = "NAME=CPU Speed"; int i, j; uint_t comp_spd; int result = DDI_FAILURE; pmc = kmem_zalloc((cpupm->num_spd + 1) * sizeof (char *), KM_SLEEP); size = CPUDRV_COMP_SIZE(); if (cpupm->num_spd > CPUDRV_COMP_MAX_VAL) { cmn_err(CE_WARN, "cpudrv_comp_create: instance %d: " "number of speeds exceeded limits", ddi_get_instance(cpudsp->dip)); kmem_free(pmc, (cpupm->num_spd + 1) * sizeof (char *)); return (result); } for (i = cpupm->num_spd, cur_spd = cpupm->head_spd; i > 0; i--, cur_spd = cur_spd->down_spd) { cur_spd->pm_level = i; pmc[i] = kmem_zalloc((size * sizeof (char)), KM_SLEEP); comp_spd = CPUDRV_COMP_SPEED(cpupm, cur_spd); if (comp_spd > CPUDRV_COMP_MAX_VAL) { cmn_err(CE_WARN, "cpudrv_comp_create: " "instance %d: speed exceeded limits", ddi_get_instance(cpudsp->dip)); for (j = cpupm->num_spd; j >= i; j--) { kmem_free(pmc[j], size * sizeof (char)); } kmem_free(pmc, (cpupm->num_spd + 1) * sizeof (char *)); return (result); } CPUDRV_COMP_SPRINT(pmc[i], cpupm, cur_spd, comp_spd) DPRINTF(D_PM_COMP_CREATE, ("cpudrv_comp_create: " "instance %d: pm-components power level %d string '%s'\n", ddi_get_instance(cpudsp->dip), i, pmc[i])); } pmc[0] = kmem_zalloc(sizeof (name), KM_SLEEP); (void) strcat(pmc[0], name); DPRINTF(D_PM_COMP_CREATE, ("cpudrv_comp_create: instance %d: " "pm-components component name '%s'\n", ddi_get_instance(cpudsp->dip), pmc[0])); if (ddi_prop_update_string_array(DDI_DEV_T_NONE, cpudsp->dip, "pm-components", pmc, cpupm->num_spd + 1) == DDI_PROP_SUCCESS) { result = DDI_SUCCESS; } else { cmn_err(CE_WARN, "cpudrv_comp_create: instance %d: " "can't create pm-components property", ddi_get_instance(cpudsp->dip)); } for (i = cpupm->num_spd; i > 0; i--) { kmem_free(pmc[i], size * sizeof (char)); } kmem_free(pmc[0], sizeof (name)); kmem_free(pmc, (cpupm->num_spd + 1) * sizeof (char *)); return (result); } /* * Mark a component idle. */ #define CPUDRV_MONITOR_PM_IDLE_COMP(dip, cpupm) { \ if ((cpupm)->pm_busycnt >= 1) { \ if (pm_idle_component((dip), CPUDRV_COMP_NUM) == \ DDI_SUCCESS) { \ DPRINTF(D_PM_MONITOR, ("cpudrv_monitor: " \ "instance %d: pm_idle_component called\n", \ ddi_get_instance((dip)))); \ (cpupm)->pm_busycnt--; \ } else { \ cmn_err(CE_WARN, "cpudrv_monitor: instance %d: " \ "can't idle CPU component", \ ddi_get_instance((dip))); \ } \ } \ } /* * Marks a component busy in both PM framework and driver state structure. */ #define CPUDRV_MONITOR_PM_BUSY_COMP(dip, cpupm) { \ if ((cpupm)->pm_busycnt < 1) { \ if (pm_busy_component((dip), CPUDRV_COMP_NUM) == \ DDI_SUCCESS) { \ DPRINTF(D_PM_MONITOR, ("cpudrv_monitor: " \ "instance %d: pm_busy_component called\n", \ ddi_get_instance((dip)))); \ (cpupm)->pm_busycnt++; \ } else { \ cmn_err(CE_WARN, "cpudrv_monitor: instance %d: " \ "can't busy CPU component", \ ddi_get_instance((dip))); \ } \ } \ } /* * Marks a component busy and calls pm_raise_power(). */ #define CPUDRV_MONITOR_PM_BUSY_AND_RAISE(dip, cpudsp, cpupm, new_spd) { \ int ret; \ /* \ * Mark driver and PM framework busy first so framework doesn't try \ * to bring CPU to lower speed when we need to be at higher speed. \ */ \ CPUDRV_MONITOR_PM_BUSY_COMP((dip), (cpupm)); \ mutex_exit(&(cpudsp)->lock); \ DPRINTF(D_PM_MONITOR, ("cpudrv_monitor: instance %d: " \ "pm_raise_power called to %d\n", ddi_get_instance((dip)), \ (new_spd->pm_level))); \ ret = pm_raise_power((dip), CPUDRV_COMP_NUM, (new_spd->pm_level)); \ if (ret != DDI_SUCCESS) { \ cmn_err(CE_WARN, "cpudrv_monitor: instance %d: can't " \ "raise CPU power level", ddi_get_instance((dip))); \ } \ mutex_enter(&(cpudsp)->lock); \ if (ret == DDI_SUCCESS && cpudsp->cpudrv_pm.cur_spd == NULL) { \ cpudsp->cpudrv_pm.cur_spd = new_spd; \ } \ } /* * In order to monitor a CPU, we need to hold cpu_lock to access CPU * statistics. Holding cpu_lock is not allowed from a callout routine. * We dispatch a taskq to do that job. */ static void cpudrv_monitor_disp(void *arg) { cpudrv_devstate_t *cpudsp = (cpudrv_devstate_t *)arg; /* * We are here because the last task has scheduled a timeout. * The queue should be empty at this time. */ mutex_enter(&cpudsp->cpudrv_pm.timeout_lock); if ((ddi_taskq_dispatch(cpudsp->cpudrv_pm.tq, cpudrv_monitor, arg, DDI_NOSLEEP)) != DDI_SUCCESS) { mutex_exit(&cpudsp->cpudrv_pm.timeout_lock); DPRINTF(D_PM_MONITOR, ("cpudrv_monitor_disp: failed to " "dispatch the cpudrv_monitor taskq\n")); mutex_enter(&cpudsp->lock); CPUDRV_MONITOR_INIT(cpudsp); mutex_exit(&cpudsp->lock); return; } cpudsp->cpudrv_pm.timeout_count++; mutex_exit(&cpudsp->cpudrv_pm.timeout_lock); } /* * Monitors each CPU for the amount of time idle thread was running in the * last quantum and arranges for the CPU to go to the lower or higher speed. * Called at the time interval appropriate for the current speed. The * time interval for normal speed is CPUDRV_QUANT_CNT_NORMAL. The time * interval for other speeds (including unknown speed) is * CPUDRV_QUANT_CNT_OTHR. */ static void cpudrv_monitor(void *arg) { cpudrv_devstate_t *cpudsp = (cpudrv_devstate_t *)arg; cpudrv_pm_t *cpupm; cpudrv_pm_spd_t *cur_spd, *new_spd; dev_info_t *dip; uint_t idle_cnt, user_cnt, system_cnt; clock_t ticks; uint_t tick_cnt; hrtime_t msnsecs[NCMSTATES]; boolean_t is_ready; #define GET_CPU_MSTATE_CNT(state, cnt) \ msnsecs[state] = NSEC_TO_TICK(msnsecs[state]); \ if (cpupm->lastquan_mstate[state] > msnsecs[state]) \ msnsecs[state] = cpupm->lastquan_mstate[state]; \ cnt = msnsecs[state] - cpupm->lastquan_mstate[state]; \ cpupm->lastquan_mstate[state] = msnsecs[state] /* * We're not ready until we can get a cpu_t */ is_ready = (cpudrv_get_cpu(cpudsp) == DDI_SUCCESS); mutex_enter(&cpudsp->lock); cpupm = &(cpudsp->cpudrv_pm); if (cpupm->timeout_id == 0) { mutex_exit(&cpudsp->lock); goto do_return; } cur_spd = cpupm->cur_spd; dip = cpudsp->dip; /* * We assume that a CPU is initialized and has a valid cpu_t * structure, if it is ready for cross calls. If this changes, * additional checks might be needed. * * Additionally, for x86 platforms we cannot power manage an * instance, until it has been initialized. */ if (is_ready) { is_ready = CPUDRV_XCALL_IS_READY(cpudsp->cpu_id); if (!is_ready) { DPRINTF(D_PM_MONITOR, ("cpudrv_monitor: instance %d: " "CPU not ready for x-calls\n", ddi_get_instance(dip))); } else if (!(is_ready = cpudrv_power_ready(cpudsp->cp))) { DPRINTF(D_PM_MONITOR, ("cpudrv_monitor: instance %d: " "waiting for all CPUs to be power manageable\n", ddi_get_instance(dip))); } } if (!is_ready) { /* * Make sure that we are busy so that framework doesn't * try to bring us down in this situation. */ CPUDRV_MONITOR_PM_BUSY_COMP(dip, cpupm); CPUDRV_MONITOR_INIT(cpudsp); mutex_exit(&cpudsp->lock); goto do_return; } /* * Make sure that we are still not at unknown power level. */ if (cur_spd == NULL) { DPRINTF(D_PM_MONITOR, ("cpudrv_monitor: instance %d: " "cur_spd is unknown\n", ddi_get_instance(dip))); CPUDRV_MONITOR_PM_BUSY_AND_RAISE(dip, cpudsp, cpupm, CPUDRV_TOPSPEED(cpupm)); /* * We just changed the speed. Wait till at least next * call to this routine before proceeding ahead. */ CPUDRV_MONITOR_INIT(cpudsp); mutex_exit(&cpudsp->lock); goto do_return; } if (!cpupm->pm_started) { cpupm->pm_started = B_TRUE; cpudrv_set_supp_freqs(cpudsp); } get_cpu_mstate(cpudsp->cp, msnsecs); GET_CPU_MSTATE_CNT(CMS_IDLE, idle_cnt); GET_CPU_MSTATE_CNT(CMS_USER, user_cnt); GET_CPU_MSTATE_CNT(CMS_SYSTEM, system_cnt); /* * We can't do anything when we have just switched to a state * because there is no valid timestamp. */ if (cpupm->lastquan_ticks == 0) { cpupm->lastquan_ticks = NSEC_TO_TICK(gethrtime()); CPUDRV_MONITOR_INIT(cpudsp); mutex_exit(&cpudsp->lock); goto do_return; } /* * Various watermarks are based on this routine being called back * exactly at the requested period. This is not guaranteed * because this routine is called from a taskq that is dispatched * from a timeout routine. Handle this by finding out how many * ticks have elapsed since the last call and adjusting * the idle_cnt based on the delay added to the requested period * by timeout and taskq. */ ticks = NSEC_TO_TICK(gethrtime()); tick_cnt = ticks - cpupm->lastquan_ticks; ASSERT(tick_cnt != 0); cpupm->lastquan_ticks = ticks; /* * Time taken between recording the current counts and * arranging the next call of this routine is an error in our * calculation. We minimize the error by calling * CPUDRV_MONITOR_INIT() here instead of end of this routine. */ CPUDRV_MONITOR_INIT(cpudsp); DPRINTF(D_PM_MONITOR_VERBOSE, ("cpudrv_monitor: instance %d: " "idle count %d, user count %d, system count %d, pm_level %d, " "pm_busycnt %d\n", ddi_get_instance(dip), idle_cnt, user_cnt, system_cnt, cur_spd->pm_level, cpupm->pm_busycnt)); #ifdef DEBUG /* * Notify that timeout and taskq has caused delays and we need to * scale our parameters accordingly. * * To get accurate result, don't turn on other DPRINTFs with * the following DPRINTF. PROM calls generated by other * DPRINTFs changes the timing. */ if (tick_cnt > cur_spd->quant_cnt) { DPRINTF(D_PM_MONITOR_DELAY, ("cpudrv_monitor: instance %d: " "tick count %d > quantum_count %u\n", ddi_get_instance(dip), tick_cnt, cur_spd->quant_cnt)); } #endif /* DEBUG */ /* * Adjust counts based on the delay added by timeout and taskq. */ idle_cnt = (idle_cnt * cur_spd->quant_cnt) / tick_cnt; user_cnt = (user_cnt * cur_spd->quant_cnt) / tick_cnt; if ((user_cnt > cur_spd->user_hwm) || (idle_cnt < cur_spd->idle_lwm && cur_spd->idle_blwm_cnt >= cpudrv_idle_blwm_cnt_max)) { cur_spd->idle_blwm_cnt = 0; cur_spd->idle_bhwm_cnt = 0; /* * In normal situation, arrange to go to next higher speed. * If we are running in special direct pm mode, we just stay * at the current speed. */ if (cur_spd == cur_spd->up_spd || cpudrv_direct_pm) { CPUDRV_MONITOR_PM_BUSY_COMP(dip, cpupm); } else { new_spd = cur_spd->up_spd; CPUDRV_MONITOR_PM_BUSY_AND_RAISE(dip, cpudsp, cpupm, new_spd); } } else if ((user_cnt <= cur_spd->user_lwm) && (idle_cnt >= cur_spd->idle_hwm) || !CPU_ACTIVE(cpudsp->cp)) { cur_spd->idle_blwm_cnt = 0; cur_spd->idle_bhwm_cnt = 0; /* * Arrange to go to next lower speed by informing our idle * status to the power management framework. */ CPUDRV_MONITOR_PM_IDLE_COMP(dip, cpupm); } else { /* * If we are between the idle water marks and have not * been here enough consecutive times to be considered * busy, just increment the count and return. */ if ((idle_cnt < cur_spd->idle_hwm) && (idle_cnt >= cur_spd->idle_lwm) && (cur_spd->idle_bhwm_cnt < cpudrv_idle_bhwm_cnt_max)) { cur_spd->idle_blwm_cnt = 0; cur_spd->idle_bhwm_cnt++; mutex_exit(&cpudsp->lock); goto do_return; } if (idle_cnt < cur_spd->idle_lwm) { cur_spd->idle_blwm_cnt++; cur_spd->idle_bhwm_cnt = 0; } /* * Arranges to stay at the current speed. */ CPUDRV_MONITOR_PM_BUSY_COMP(dip, cpupm); } mutex_exit(&cpudsp->lock); do_return: mutex_enter(&cpupm->timeout_lock); ASSERT(cpupm->timeout_count > 0); cpupm->timeout_count--; cv_signal(&cpupm->timeout_cv); mutex_exit(&cpupm->timeout_lock); } /* * get cpu_t structure for cpudrv_devstate_t */ int cpudrv_get_cpu(cpudrv_devstate_t *cpudsp) { ASSERT(cpudsp != NULL); /* * return DDI_SUCCESS if cpudrv_devstate_t * already contains cpu_t structure */ if (cpudsp->cp != NULL) return (DDI_SUCCESS); if (MUTEX_HELD(&cpu_lock)) { cpudsp->cp = cpu_get(cpudsp->cpu_id); } else { mutex_enter(&cpu_lock); cpudsp->cp = cpu_get(cpudsp->cpu_id); mutex_exit(&cpu_lock); } if (cpudsp->cp == NULL) return (DDI_FAILURE); return (DDI_SUCCESS); }