/* * Intel Running Average Power Limit (RAPL) Driver * Copyright (c) 2013, Intel Corporation. * * This program is free software; you can redistribute it and/or modify it * under the terms and conditions of the GNU General Public License, * version 2, as published by the Free Software Foundation. * * This program is distributed in the hope it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * * You should have received a copy of the GNU General Public License along with * this program; if not, write to the Free Software Foundation, Inc. * */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* bitmasks for RAPL MSRs, used by primitive access functions */ #define ENERGY_STATUS_MASK 0xffffffff #define POWER_LIMIT1_MASK 0x7FFF #define POWER_LIMIT1_ENABLE BIT(15) #define POWER_LIMIT1_CLAMP BIT(16) #define POWER_LIMIT2_MASK (0x7FFFULL<<32) #define POWER_LIMIT2_ENABLE BIT_ULL(47) #define POWER_LIMIT2_CLAMP BIT_ULL(48) #define POWER_PACKAGE_LOCK BIT_ULL(63) #define POWER_PP_LOCK BIT(31) #define TIME_WINDOW1_MASK (0x7FULL<<17) #define TIME_WINDOW2_MASK (0x7FULL<<49) #define POWER_UNIT_OFFSET 0 #define POWER_UNIT_MASK 0x0F #define ENERGY_UNIT_OFFSET 0x08 #define ENERGY_UNIT_MASK 0x1F00 #define TIME_UNIT_OFFSET 0x10 #define TIME_UNIT_MASK 0xF0000 #define POWER_INFO_MAX_MASK (0x7fffULL<<32) #define POWER_INFO_MIN_MASK (0x7fffULL<<16) #define POWER_INFO_MAX_TIME_WIN_MASK (0x3fULL<<48) #define POWER_INFO_THERMAL_SPEC_MASK 0x7fff #define PERF_STATUS_THROTTLE_TIME_MASK 0xffffffff #define PP_POLICY_MASK 0x1F /* Non HW constants */ #define RAPL_PRIMITIVE_DERIVED BIT(1) /* not from raw data */ #define RAPL_PRIMITIVE_DUMMY BIT(2) /* scale RAPL units to avoid floating point math inside kernel */ #define POWER_UNIT_SCALE (1000000) #define ENERGY_UNIT_SCALE (1000000) #define TIME_UNIT_SCALE (1000000) #define TIME_WINDOW_MAX_MSEC 40000 #define TIME_WINDOW_MIN_MSEC 250 enum unit_type { ARBITRARY_UNIT, /* no translation */ POWER_UNIT, ENERGY_UNIT, TIME_UNIT, }; enum rapl_domain_type { RAPL_DOMAIN_PACKAGE, /* entire package/socket */ RAPL_DOMAIN_PP0, /* core power plane */ RAPL_DOMAIN_PP1, /* graphics uncore */ RAPL_DOMAIN_DRAM,/* DRAM control_type */ RAPL_DOMAIN_MAX, }; enum rapl_domain_msr_id { RAPL_DOMAIN_MSR_LIMIT, RAPL_DOMAIN_MSR_STATUS, RAPL_DOMAIN_MSR_PERF, RAPL_DOMAIN_MSR_POLICY, RAPL_DOMAIN_MSR_INFO, RAPL_DOMAIN_MSR_MAX, }; /* per domain data, some are optional */ enum rapl_primitives { ENERGY_COUNTER, POWER_LIMIT1, POWER_LIMIT2, FW_LOCK, PL1_ENABLE, /* power limit 1, aka long term */ PL1_CLAMP, /* allow frequency to go below OS request */ PL2_ENABLE, /* power limit 2, aka short term, instantaneous */ PL2_CLAMP, TIME_WINDOW1, /* long term */ TIME_WINDOW2, /* short term */ THERMAL_SPEC_POWER, MAX_POWER, MIN_POWER, MAX_TIME_WINDOW, THROTTLED_TIME, PRIORITY_LEVEL, /* below are not raw primitive data */ AVERAGE_POWER, NR_RAPL_PRIMITIVES, }; #define NR_RAW_PRIMITIVES (NR_RAPL_PRIMITIVES - 2) /* Can be expanded to include events, etc.*/ struct rapl_domain_data { u64 primitives[NR_RAPL_PRIMITIVES]; unsigned long timestamp; }; #define DOMAIN_STATE_INACTIVE BIT(0) #define DOMAIN_STATE_POWER_LIMIT_SET BIT(1) #define DOMAIN_STATE_BIOS_LOCKED BIT(2) #define NR_POWER_LIMITS (2) struct rapl_power_limit { struct powercap_zone_constraint *constraint; int prim_id; /* primitive ID used to enable */ struct rapl_domain *domain; const char *name; }; static const char pl1_name[] = "long_term"; static const char pl2_name[] = "short_term"; struct rapl_domain { const char *name; enum rapl_domain_type id; int msrs[RAPL_DOMAIN_MSR_MAX]; struct powercap_zone power_zone; struct rapl_domain_data rdd; struct rapl_power_limit rpl[NR_POWER_LIMITS]; u64 attr_map; /* track capabilities */ unsigned int state; int package_id; }; #define power_zone_to_rapl_domain(_zone) \ container_of(_zone, struct rapl_domain, power_zone) /* Each physical package contains multiple domains, these are the common * data across RAPL domains within a package. */ struct rapl_package { unsigned int id; /* physical package/socket id */ unsigned int nr_domains; unsigned long domain_map; /* bit map of active domains */ unsigned int power_unit_divisor; unsigned int energy_unit_divisor; unsigned int time_unit_divisor; struct rapl_domain *domains; /* array of domains, sized at runtime */ struct powercap_zone *power_zone; /* keep track of parent zone */ int nr_cpus; /* active cpus on the package, topology info is lost during * cpu hotplug. so we have to track ourselves. */ unsigned long power_limit_irq; /* keep track of package power limit * notify interrupt enable status. */ struct list_head plist; }; #define PACKAGE_PLN_INT_SAVED BIT(0) #define MAX_PRIM_NAME (32) /* per domain data. used to describe individual knobs such that access function * can be consolidated into one instead of many inline functions. */ struct rapl_primitive_info { const char *name; u64 mask; int shift; enum rapl_domain_msr_id id; enum unit_type unit; u32 flag; }; #define PRIMITIVE_INFO_INIT(p, m, s, i, u, f) { \ .name = #p, \ .mask = m, \ .shift = s, \ .id = i, \ .unit = u, \ .flag = f \ } static void rapl_init_domains(struct rapl_package *rp); static int rapl_read_data_raw(struct rapl_domain *rd, enum rapl_primitives prim, bool xlate, u64 *data); static int rapl_write_data_raw(struct rapl_domain *rd, enum rapl_primitives prim, unsigned long long value); static u64 rapl_unit_xlate(int package, enum unit_type type, u64 value, int to_raw); static void package_power_limit_irq_save(int package_id); static LIST_HEAD(rapl_packages); /* guarded by CPU hotplug lock */ static const char * const rapl_domain_names[] = { "package", "core", "uncore", "dram", }; static struct powercap_control_type *control_type; /* PowerCap Controller */ /* caller to ensure CPU hotplug lock is held */ static struct rapl_package *find_package_by_id(int id) { struct rapl_package *rp; list_for_each_entry(rp, &rapl_packages, plist) { if (rp->id == id) return rp; } return NULL; } /* caller to ensure CPU hotplug lock is held */ static int find_active_cpu_on_package(int package_id) { int i; for_each_online_cpu(i) { if (topology_physical_package_id(i) == package_id) return i; } /* all CPUs on this package are offline */ return -ENODEV; } /* caller must hold cpu hotplug lock */ static void rapl_cleanup_data(void) { struct rapl_package *p, *tmp; list_for_each_entry_safe(p, tmp, &rapl_packages, plist) { kfree(p->domains); list_del(&p->plist); kfree(p); } } static int get_energy_counter(struct powercap_zone *power_zone, u64 *energy_raw) { struct rapl_domain *rd; u64 energy_now; /* prevent CPU hotplug, make sure the RAPL domain does not go * away while reading the counter. */ get_online_cpus(); rd = power_zone_to_rapl_domain(power_zone); if (!rapl_read_data_raw(rd, ENERGY_COUNTER, true, &energy_now)) { *energy_raw = energy_now; put_online_cpus(); return 0; } put_online_cpus(); return -EIO; } static int get_max_energy_counter(struct powercap_zone *pcd_dev, u64 *energy) { *energy = rapl_unit_xlate(0, ENERGY_UNIT, ENERGY_STATUS_MASK, 0); return 0; } static int release_zone(struct powercap_zone *power_zone) { struct rapl_domain *rd = power_zone_to_rapl_domain(power_zone); struct rapl_package *rp; /* package zone is the last zone of a package, we can free * memory here since all children has been unregistered. */ if (rd->id == RAPL_DOMAIN_PACKAGE) { rp = find_package_by_id(rd->package_id); if (!rp) { dev_warn(&power_zone->dev, "no package id %s\n", rd->name); return -ENODEV; } kfree(rd); rp->domains = NULL; } return 0; } static int find_nr_power_limit(struct rapl_domain *rd) { int i; for (i = 0; i < NR_POWER_LIMITS; i++) { if (rd->rpl[i].name == NULL) break; } return i; } static int set_domain_enable(struct powercap_zone *power_zone, bool mode) { struct rapl_domain *rd = power_zone_to_rapl_domain(power_zone); int nr_powerlimit; if (rd->state & DOMAIN_STATE_BIOS_LOCKED) return -EACCES; get_online_cpus(); nr_powerlimit = find_nr_power_limit(rd); /* here we activate/deactivate the hardware for power limiting */ rapl_write_data_raw(rd, PL1_ENABLE, mode); /* always enable clamp such that p-state can go below OS requested * range. power capping priority over guranteed frequency. */ rapl_write_data_raw(rd, PL1_CLAMP, mode); /* some domains have pl2 */ if (nr_powerlimit > 1) { rapl_write_data_raw(rd, PL2_ENABLE, mode); rapl_write_data_raw(rd, PL2_CLAMP, mode); } put_online_cpus(); return 0; } static int get_domain_enable(struct powercap_zone *power_zone, bool *mode) { struct rapl_domain *rd = power_zone_to_rapl_domain(power_zone); u64 val; if (rd->state & DOMAIN_STATE_BIOS_LOCKED) { *mode = false; return 0; } get_online_cpus(); if (rapl_read_data_raw(rd, PL1_ENABLE, true, &val)) { put_online_cpus(); return -EIO; } *mode = val; put_online_cpus(); return 0; } /* per RAPL domain ops, in the order of rapl_domain_type */ static struct powercap_zone_ops zone_ops[] = { /* RAPL_DOMAIN_PACKAGE */ { .get_energy_uj = get_energy_counter, .get_max_energy_range_uj = get_max_energy_counter, .release = release_zone, .set_enable = set_domain_enable, .get_enable = get_domain_enable, }, /* RAPL_DOMAIN_PP0 */ { .get_energy_uj = get_energy_counter, .get_max_energy_range_uj = get_max_energy_counter, .release = release_zone, .set_enable = set_domain_enable, .get_enable = get_domain_enable, }, /* RAPL_DOMAIN_PP1 */ { .get_energy_uj = get_energy_counter, .get_max_energy_range_uj = get_max_energy_counter, .release = release_zone, .set_enable = set_domain_enable, .get_enable = get_domain_enable, }, /* RAPL_DOMAIN_DRAM */ { .get_energy_uj = get_energy_counter, .get_max_energy_range_uj = get_max_energy_counter, .release = release_zone, .set_enable = set_domain_enable, .get_enable = get_domain_enable, }, }; static int set_power_limit(struct powercap_zone *power_zone, int id, u64 power_limit) { struct rapl_domain *rd; struct rapl_package *rp; int ret = 0; get_online_cpus(); rd = power_zone_to_rapl_domain(power_zone); rp = find_package_by_id(rd->package_id); if (!rp) { ret = -ENODEV; goto set_exit; } if (rd->state & DOMAIN_STATE_BIOS_LOCKED) { dev_warn(&power_zone->dev, "%s locked by BIOS, monitoring only\n", rd->name); ret = -EACCES; goto set_exit; } switch (rd->rpl[id].prim_id) { case PL1_ENABLE: rapl_write_data_raw(rd, POWER_LIMIT1, power_limit); break; case PL2_ENABLE: rapl_write_data_raw(rd, POWER_LIMIT2, power_limit); break; default: ret = -EINVAL; } if (!ret) package_power_limit_irq_save(rd->package_id); set_exit: put_online_cpus(); return ret; } static int get_current_power_limit(struct powercap_zone *power_zone, int id, u64 *data) { struct rapl_domain *rd; u64 val; int prim; int ret = 0; get_online_cpus(); rd = power_zone_to_rapl_domain(power_zone); switch (rd->rpl[id].prim_id) { case PL1_ENABLE: prim = POWER_LIMIT1; break; case PL2_ENABLE: prim = POWER_LIMIT2; break; default: put_online_cpus(); return -EINVAL; } if (rapl_read_data_raw(rd, prim, true, &val)) ret = -EIO; else *data = val; put_online_cpus(); return ret; } static int set_time_window(struct powercap_zone *power_zone, int id, u64 window) { struct rapl_domain *rd; int ret = 0; get_online_cpus(); rd = power_zone_to_rapl_domain(power_zone); switch (rd->rpl[id].prim_id) { case PL1_ENABLE: rapl_write_data_raw(rd, TIME_WINDOW1, window); break; case PL2_ENABLE: rapl_write_data_raw(rd, TIME_WINDOW2, window); break; default: ret = -EINVAL; } put_online_cpus(); return ret; } static int get_time_window(struct powercap_zone *power_zone, int id, u64 *data) { struct rapl_domain *rd; u64 val; int ret = 0; get_online_cpus(); rd = power_zone_to_rapl_domain(power_zone); switch (rd->rpl[id].prim_id) { case PL1_ENABLE: ret = rapl_read_data_raw(rd, TIME_WINDOW1, true, &val); break; case PL2_ENABLE: ret = rapl_read_data_raw(rd, TIME_WINDOW2, true, &val); break; default: put_online_cpus(); return -EINVAL; } if (!ret) *data = val; put_online_cpus(); return ret; } static const char *get_constraint_name(struct powercap_zone *power_zone, int id) { struct rapl_power_limit *rpl; struct rapl_domain *rd; rd = power_zone_to_rapl_domain(power_zone); rpl = (struct rapl_power_limit *) &rd->rpl[id]; return rpl->name; } static int get_max_power(struct powercap_zone *power_zone, int id, u64 *data) { struct rapl_domain *rd; u64 val; int prim; int ret = 0; get_online_cpus(); rd = power_zone_to_rapl_domain(power_zone); switch (rd->rpl[id].prim_id) { case PL1_ENABLE: prim = THERMAL_SPEC_POWER; break; case PL2_ENABLE: prim = MAX_POWER; break; default: put_online_cpus(); return -EINVAL; } if (rapl_read_data_raw(rd, prim, true, &val)) ret = -EIO; else *data = val; put_online_cpus(); return ret; } static struct powercap_zone_constraint_ops constraint_ops = { .set_power_limit_uw = set_power_limit, .get_power_limit_uw = get_current_power_limit, .set_time_window_us = set_time_window, .get_time_window_us = get_time_window, .get_max_power_uw = get_max_power, .get_name = get_constraint_name, }; /* called after domain detection and package level data are set */ static void rapl_init_domains(struct rapl_package *rp) { int i; struct rapl_domain *rd = rp->domains; for (i = 0; i < RAPL_DOMAIN_MAX; i++) { unsigned int mask = rp->domain_map & (1 << i); switch (mask) { case BIT(RAPL_DOMAIN_PACKAGE): rd->name = rapl_domain_names[RAPL_DOMAIN_PACKAGE]; rd->id = RAPL_DOMAIN_PACKAGE; rd->msrs[0] = MSR_PKG_POWER_LIMIT; rd->msrs[1] = MSR_PKG_ENERGY_STATUS; rd->msrs[2] = MSR_PKG_PERF_STATUS; rd->msrs[3] = 0; rd->msrs[4] = MSR_PKG_POWER_INFO; rd->rpl[0].prim_id = PL1_ENABLE; rd->rpl[0].name = pl1_name; rd->rpl[1].prim_id = PL2_ENABLE; rd->rpl[1].name = pl2_name; break; case BIT(RAPL_DOMAIN_PP0): rd->name = rapl_domain_names[RAPL_DOMAIN_PP0]; rd->id = RAPL_DOMAIN_PP0; rd->msrs[0] = MSR_PP0_POWER_LIMIT; rd->msrs[1] = MSR_PP0_ENERGY_STATUS; rd->msrs[2] = 0; rd->msrs[3] = MSR_PP0_POLICY; rd->msrs[4] = 0; rd->rpl[0].prim_id = PL1_ENABLE; rd->rpl[0].name = pl1_name; break; case BIT(RAPL_DOMAIN_PP1): rd->name = rapl_domain_names[RAPL_DOMAIN_PP1]; rd->id = RAPL_DOMAIN_PP1; rd->msrs[0] = MSR_PP1_POWER_LIMIT; rd->msrs[1] = MSR_PP1_ENERGY_STATUS; rd->msrs[2] = 0; rd->msrs[3] = MSR_PP1_POLICY; rd->msrs[4] = 0; rd->rpl[0].prim_id = PL1_ENABLE; rd->rpl[0].name = pl1_name; break; case BIT(RAPL_DOMAIN_DRAM): rd->name = rapl_domain_names[RAPL_DOMAIN_DRAM]; rd->id = RAPL_DOMAIN_DRAM; rd->msrs[0] = MSR_DRAM_POWER_LIMIT; rd->msrs[1] = MSR_DRAM_ENERGY_STATUS; rd->msrs[2] = MSR_DRAM_PERF_STATUS; rd->msrs[3] = 0; rd->msrs[4] = MSR_DRAM_POWER_INFO; rd->rpl[0].prim_id = PL1_ENABLE; rd->rpl[0].name = pl1_name; break; } if (mask) { rd->package_id = rp->id; rd++; } } } static u64 rapl_unit_xlate(int package, enum unit_type type, u64 value, int to_raw) { u64 divisor = 1; int scale = 1; /* scale to user friendly data without floating point */ u64 f, y; /* fraction and exp. used for time unit */ struct rapl_package *rp; rp = find_package_by_id(package); if (!rp) return value; switch (type) { case POWER_UNIT: divisor = rp->power_unit_divisor; scale = POWER_UNIT_SCALE; break; case ENERGY_UNIT: scale = ENERGY_UNIT_SCALE; divisor = rp->energy_unit_divisor; break; case TIME_UNIT: divisor = rp->time_unit_divisor; scale = TIME_UNIT_SCALE; /* special processing based on 2^Y*(1+F)/4 = val/divisor, refer * to Intel Software Developer's manual Vol. 3a, CH 14.7.4. */ if (!to_raw) { f = (value & 0x60) >> 5; y = value & 0x1f; value = (1 << y) * (4 + f) * scale / 4; return div64_u64(value, divisor); } else { do_div(value, scale); value *= divisor; y = ilog2(value); f = div64_u64(4 * (value - (1 << y)), 1 << y); value = (y & 0x1f) | ((f & 0x3) << 5); return value; } break; case ARBITRARY_UNIT: default: return value; }; if (to_raw) return div64_u64(value * divisor, scale); else return div64_u64(value * scale, divisor); } /* in the order of enum rapl_primitives */ static struct rapl_primitive_info rpi[] = { /* name, mask, shift, msr index, unit divisor */ PRIMITIVE_INFO_INIT(ENERGY_COUNTER, ENERGY_STATUS_MASK, 0, RAPL_DOMAIN_MSR_STATUS, ENERGY_UNIT, 0), PRIMITIVE_INFO_INIT(POWER_LIMIT1, POWER_LIMIT1_MASK, 0, RAPL_DOMAIN_MSR_LIMIT, POWER_UNIT, 0), PRIMITIVE_INFO_INIT(POWER_LIMIT2, POWER_LIMIT2_MASK, 32, RAPL_DOMAIN_MSR_LIMIT, POWER_UNIT, 0), PRIMITIVE_INFO_INIT(FW_LOCK, POWER_PP_LOCK, 31, RAPL_DOMAIN_MSR_LIMIT, ARBITRARY_UNIT, 0), PRIMITIVE_INFO_INIT(PL1_ENABLE, POWER_LIMIT1_ENABLE, 15, RAPL_DOMAIN_MSR_LIMIT, ARBITRARY_UNIT, 0), PRIMITIVE_INFO_INIT(PL1_CLAMP, POWER_LIMIT1_CLAMP, 16, RAPL_DOMAIN_MSR_LIMIT, ARBITRARY_UNIT, 0), PRIMITIVE_INFO_INIT(PL2_ENABLE, POWER_LIMIT2_ENABLE, 47, RAPL_DOMAIN_MSR_LIMIT, ARBITRARY_UNIT, 0), PRIMITIVE_INFO_INIT(PL2_CLAMP, POWER_LIMIT2_CLAMP, 48, RAPL_DOMAIN_MSR_LIMIT, ARBITRARY_UNIT, 0), PRIMITIVE_INFO_INIT(TIME_WINDOW1, TIME_WINDOW1_MASK, 17, RAPL_DOMAIN_MSR_LIMIT, TIME_UNIT, 0), PRIMITIVE_INFO_INIT(TIME_WINDOW2, TIME_WINDOW2_MASK, 49, RAPL_DOMAIN_MSR_LIMIT, TIME_UNIT, 0), PRIMITIVE_INFO_INIT(THERMAL_SPEC_POWER, POWER_INFO_THERMAL_SPEC_MASK, 0, RAPL_DOMAIN_MSR_INFO, POWER_UNIT, 0), PRIMITIVE_INFO_INIT(MAX_POWER, POWER_INFO_MAX_MASK, 32, RAPL_DOMAIN_MSR_INFO, POWER_UNIT, 0), PRIMITIVE_INFO_INIT(MIN_POWER, POWER_INFO_MIN_MASK, 16, RAPL_DOMAIN_MSR_INFO, POWER_UNIT, 0), PRIMITIVE_INFO_INIT(MAX_TIME_WINDOW, POWER_INFO_MAX_TIME_WIN_MASK, 48, RAPL_DOMAIN_MSR_INFO, TIME_UNIT, 0), PRIMITIVE_INFO_INIT(THROTTLED_TIME, PERF_STATUS_THROTTLE_TIME_MASK, 0, RAPL_DOMAIN_MSR_PERF, TIME_UNIT, 0), PRIMITIVE_INFO_INIT(PRIORITY_LEVEL, PP_POLICY_MASK, 0, RAPL_DOMAIN_MSR_POLICY, ARBITRARY_UNIT, 0), /* non-hardware */ PRIMITIVE_INFO_INIT(AVERAGE_POWER, 0, 0, 0, POWER_UNIT, RAPL_PRIMITIVE_DERIVED), {NULL, 0, 0, 0}, }; /* Read primitive data based on its related struct rapl_primitive_info. * if xlate flag is set, return translated data based on data units, i.e. * time, energy, and power. * RAPL MSRs are non-architectual and are laid out not consistently across * domains. Here we use primitive info to allow writing consolidated access * functions. * For a given primitive, it is processed by MSR mask and shift. Unit conversion * is pre-assigned based on RAPL unit MSRs read at init time. * 63-------------------------- 31--------------------------- 0 * | xxxxx (mask) | * | |<- shift ----------------| * 63-------------------------- 31--------------------------- 0 */ static int rapl_read_data_raw(struct rapl_domain *rd, enum rapl_primitives prim, bool xlate, u64 *data) { u64 value, final; u32 msr; struct rapl_primitive_info *rp = &rpi[prim]; int cpu; if (!rp->name || rp->flag & RAPL_PRIMITIVE_DUMMY) return -EINVAL; msr = rd->msrs[rp->id]; if (!msr) return -EINVAL; /* use physical package id to look up active cpus */ cpu = find_active_cpu_on_package(rd->package_id); if (cpu < 0) return cpu; /* special-case package domain, which uses a different bit*/ if (prim == FW_LOCK && rd->id == RAPL_DOMAIN_PACKAGE) { rp->mask = POWER_PACKAGE_LOCK; rp->shift = 63; } /* non-hardware data are collected by the polling thread */ if (rp->flag & RAPL_PRIMITIVE_DERIVED) { *data = rd->rdd.primitives[prim]; return 0; } if (rdmsrl_safe_on_cpu(cpu, msr, &value)) { pr_debug("failed to read msr 0x%x on cpu %d\n", msr, cpu); return -EIO; } final = value & rp->mask; final = final >> rp->shift; if (xlate) *data = rapl_unit_xlate(rd->package_id, rp->unit, final, 0); else *data = final; return 0; } /* Similar use of primitive info in the read counterpart */ static int rapl_write_data_raw(struct rapl_domain *rd, enum rapl_primitives prim, unsigned long long value) { u64 msr_val; u32 msr; struct rapl_primitive_info *rp = &rpi[prim]; int cpu; cpu = find_active_cpu_on_package(rd->package_id); if (cpu < 0) return cpu; msr = rd->msrs[rp->id]; if (rdmsrl_safe_on_cpu(cpu, msr, &msr_val)) { dev_dbg(&rd->power_zone.dev, "failed to read msr 0x%x on cpu %d\n", msr, cpu); return -EIO; } value = rapl_unit_xlate(rd->package_id, rp->unit, value, 1); msr_val &= ~rp->mask; msr_val |= value << rp->shift; if (wrmsrl_safe_on_cpu(cpu, msr, msr_val)) { dev_dbg(&rd->power_zone.dev, "failed to write msr 0x%x on cpu %d\n", msr, cpu); return -EIO; } return 0; } static const struct x86_cpu_id energy_unit_quirk_ids[] = { { X86_VENDOR_INTEL, 6, 0x37},/* Valleyview */ {} }; static int rapl_check_unit(struct rapl_package *rp, int cpu) { u64 msr_val; u32 value; if (rdmsrl_safe_on_cpu(cpu, MSR_RAPL_POWER_UNIT, &msr_val)) { pr_err("Failed to read power unit MSR 0x%x on CPU %d, exit.\n", MSR_RAPL_POWER_UNIT, cpu); return -ENODEV; } /* Raw RAPL data stored in MSRs are in certain scales. We need to * convert them into standard units based on the divisors reported in * the RAPL unit MSRs. * i.e. * energy unit: 1/enery_unit_divisor Joules * power unit: 1/power_unit_divisor Watts * time unit: 1/time_unit_divisor Seconds */ value = (msr_val & ENERGY_UNIT_MASK) >> ENERGY_UNIT_OFFSET; /* some CPUs have different way to calculate energy unit */ if (x86_match_cpu(energy_unit_quirk_ids)) rp->energy_unit_divisor = 1000000 / (1 << value); else rp->energy_unit_divisor = 1 << value; value = (msr_val & POWER_UNIT_MASK) >> POWER_UNIT_OFFSET; rp->power_unit_divisor = 1 << value; value = (msr_val & TIME_UNIT_MASK) >> TIME_UNIT_OFFSET; rp->time_unit_divisor = 1 << value; pr_debug("Physical package %d units: energy=%d, time=%d, power=%d\n", rp->id, rp->energy_unit_divisor, rp->time_unit_divisor, rp->power_unit_divisor); return 0; } /* REVISIT: * When package power limit is set artificially low by RAPL, LVT * thermal interrupt for package power limit should be ignored * since we are not really exceeding the real limit. The intention * is to avoid excessive interrupts while we are trying to save power. * A useful feature might be routing the package_power_limit interrupt * to userspace via eventfd. once we have a usecase, this is simple * to do by adding an atomic notifier. */ static void package_power_limit_irq_save(int package_id) { u32 l, h = 0; int cpu; struct rapl_package *rp; rp = find_package_by_id(package_id); if (!rp) return; if (!boot_cpu_has(X86_FEATURE_PTS) || !boot_cpu_has(X86_FEATURE_PLN)) return; cpu = find_active_cpu_on_package(package_id); if (cpu < 0) return; /* save the state of PLN irq mask bit before disabling it */ rdmsr_safe_on_cpu(cpu, MSR_IA32_PACKAGE_THERM_INTERRUPT, &l, &h); if (!(rp->power_limit_irq & PACKAGE_PLN_INT_SAVED)) { rp->power_limit_irq = l & PACKAGE_THERM_INT_PLN_ENABLE; rp->power_limit_irq |= PACKAGE_PLN_INT_SAVED; } l &= ~PACKAGE_THERM_INT_PLN_ENABLE; wrmsr_on_cpu(cpu, MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h); } /* restore per package power limit interrupt enable state */ static void package_power_limit_irq_restore(int package_id) { u32 l, h; int cpu; struct rapl_package *rp; rp = find_package_by_id(package_id); if (!rp) return; if (!boot_cpu_has(X86_FEATURE_PTS) || !boot_cpu_has(X86_FEATURE_PLN)) return; cpu = find_active_cpu_on_package(package_id); if (cpu < 0) return; /* irq enable state not saved, nothing to restore */ if (!(rp->power_limit_irq & PACKAGE_PLN_INT_SAVED)) return; rdmsr_safe_on_cpu(cpu, MSR_IA32_PACKAGE_THERM_INTERRUPT, &l, &h); if (rp->power_limit_irq & PACKAGE_THERM_INT_PLN_ENABLE) l |= PACKAGE_THERM_INT_PLN_ENABLE; else l &= ~PACKAGE_THERM_INT_PLN_ENABLE; wrmsr_on_cpu(cpu, MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h); } static const struct x86_cpu_id rapl_ids[] = { { X86_VENDOR_INTEL, 6, 0x2a},/* Sandy Bridge */ { X86_VENDOR_INTEL, 6, 0x2d},/* Sandy Bridge EP */ { X86_VENDOR_INTEL, 6, 0x37},/* Valleyview */ { X86_VENDOR_INTEL, 6, 0x3a},/* Ivy Bridge */ { X86_VENDOR_INTEL, 6, 0x45},/* Haswell */ /* TODO: Add more CPU IDs after testing */ {} }; MODULE_DEVICE_TABLE(x86cpu, rapl_ids); /* read once for all raw primitive data for all packages, domains */ static void rapl_update_domain_data(void) { int dmn, prim; u64 val; struct rapl_package *rp; list_for_each_entry(rp, &rapl_packages, plist) { for (dmn = 0; dmn < rp->nr_domains; dmn++) { pr_debug("update package %d domain %s data\n", rp->id, rp->domains[dmn].name); /* exclude non-raw primitives */ for (prim = 0; prim < NR_RAW_PRIMITIVES; prim++) if (!rapl_read_data_raw(&rp->domains[dmn], prim, rpi[prim].unit, &val)) rp->domains[dmn].rdd.primitives[prim] = val; } } } static int rapl_unregister_powercap(void) { struct rapl_package *rp; struct rapl_domain *rd, *rd_package = NULL; /* unregister all active rapl packages from the powercap layer, * hotplug lock held */ list_for_each_entry(rp, &rapl_packages, plist) { package_power_limit_irq_restore(rp->id); for (rd = rp->domains; rd < rp->domains + rp->nr_domains; rd++) { pr_debug("remove package, undo power limit on %d: %s\n", rp->id, rd->name); rapl_write_data_raw(rd, PL1_ENABLE, 0); rapl_write_data_raw(rd, PL2_ENABLE, 0); rapl_write_data_raw(rd, PL1_CLAMP, 0); rapl_write_data_raw(rd, PL2_CLAMP, 0); if (rd->id == RAPL_DOMAIN_PACKAGE) { rd_package = rd; continue; } powercap_unregister_zone(control_type, &rd->power_zone); } /* do the package zone last */ if (rd_package) powercap_unregister_zone(control_type, &rd_package->power_zone); } powercap_unregister_control_type(control_type); return 0; } static int rapl_package_register_powercap(struct rapl_package *rp) { struct rapl_domain *rd; int ret = 0; char dev_name[17]; /* max domain name = 7 + 1 + 8 for int + 1 for null*/ struct powercap_zone *power_zone = NULL; int nr_pl; /* first we register package domain as the parent zone*/ for (rd = rp->domains; rd < rp->domains + rp->nr_domains; rd++) { if (rd->id == RAPL_DOMAIN_PACKAGE) { nr_pl = find_nr_power_limit(rd); pr_debug("register socket %d package domain %s\n", rp->id, rd->name); memset(dev_name, 0, sizeof(dev_name)); snprintf(dev_name, sizeof(dev_name), "%s-%d", rd->name, rp->id); power_zone = powercap_register_zone(&rd->power_zone, control_type, dev_name, NULL, &zone_ops[rd->id], nr_pl, &constraint_ops); if (IS_ERR(power_zone)) { pr_debug("failed to register package, %d\n", rp->id); ret = PTR_ERR(power_zone); goto exit_package; } /* track parent zone in per package/socket data */ rp->power_zone = power_zone; /* done, only one package domain per socket */ break; } } if (!power_zone) { pr_err("no package domain found, unknown topology!\n"); ret = -ENODEV; goto exit_package; } /* now register domains as children of the socket/package*/ for (rd = rp->domains; rd < rp->domains + rp->nr_domains; rd++) { if (rd->id == RAPL_DOMAIN_PACKAGE) continue; /* number of power limits per domain varies */ nr_pl = find_nr_power_limit(rd); power_zone = powercap_register_zone(&rd->power_zone, control_type, rd->name, rp->power_zone, &zone_ops[rd->id], nr_pl, &constraint_ops); if (IS_ERR(power_zone)) { pr_debug("failed to register power_zone, %d:%s:%s\n", rp->id, rd->name, dev_name); ret = PTR_ERR(power_zone); goto err_cleanup; } } exit_package: return ret; err_cleanup: /* clean up previously initialized domains within the package if we * failed after the first domain setup. */ while (--rd >= rp->domains) { pr_debug("unregister package %d domain %s\n", rp->id, rd->name); powercap_unregister_zone(control_type, &rd->power_zone); } return ret; } static int rapl_register_powercap(void) { struct rapl_domain *rd; struct rapl_package *rp; int ret = 0; control_type = powercap_register_control_type(NULL, "intel-rapl", NULL); if (IS_ERR(control_type)) { pr_debug("failed to register powercap control_type.\n"); return PTR_ERR(control_type); } /* read the initial data */ rapl_update_domain_data(); list_for_each_entry(rp, &rapl_packages, plist) if (rapl_package_register_powercap(rp)) goto err_cleanup_package; return ret; err_cleanup_package: /* clean up previously initialized packages */ list_for_each_entry_continue_reverse(rp, &rapl_packages, plist) { for (rd = rp->domains; rd < rp->domains + rp->nr_domains; rd++) { pr_debug("unregister zone/package %d, %s domain\n", rp->id, rd->name); powercap_unregister_zone(control_type, &rd->power_zone); } } return ret; } static int rapl_check_domain(int cpu, int domain) { unsigned msr; u64 val = 0; switch (domain) { case RAPL_DOMAIN_PACKAGE: msr = MSR_PKG_ENERGY_STATUS; break; case RAPL_DOMAIN_PP0: msr = MSR_PP0_ENERGY_STATUS; break; case RAPL_DOMAIN_PP1: msr = MSR_PP1_ENERGY_STATUS; break; case RAPL_DOMAIN_DRAM: msr = MSR_DRAM_ENERGY_STATUS; break; default: pr_err("invalid domain id %d\n", domain); return -EINVAL; } /* make sure domain counters are available and contains non-zero * values, otherwise skip it. */ if (rdmsrl_safe_on_cpu(cpu, msr, &val) || !val) return -ENODEV; return 0; } /* Detect active and valid domains for the given CPU, caller must * ensure the CPU belongs to the targeted package and CPU hotlug is disabled. */ static int rapl_detect_domains(struct rapl_package *rp, int cpu) { int i; int ret = 0; struct rapl_domain *rd; u64 locked; for (i = 0; i < RAPL_DOMAIN_MAX; i++) { /* use physical package id to read counters */ if (!rapl_check_domain(cpu, i)) rp->domain_map |= 1 << i; else pr_warn("RAPL domain %s detection failed\n", rapl_domain_names[i]); } rp->nr_domains = bitmap_weight(&rp->domain_map, RAPL_DOMAIN_MAX); if (!rp->nr_domains) { pr_err("no valid rapl domains found in package %d\n", rp->id); ret = -ENODEV; goto done; } pr_debug("found %d domains on package %d\n", rp->nr_domains, rp->id); rp->domains = kcalloc(rp->nr_domains + 1, sizeof(struct rapl_domain), GFP_KERNEL); if (!rp->domains) { ret = -ENOMEM; goto done; } rapl_init_domains(rp); for (rd = rp->domains; rd < rp->domains + rp->nr_domains; rd++) { /* check if the domain is locked by BIOS */ if (rapl_read_data_raw(rd, FW_LOCK, false, &locked)) { pr_info("RAPL package %d domain %s locked by BIOS\n", rp->id, rd->name); rd->state |= DOMAIN_STATE_BIOS_LOCKED; } } done: return ret; } static bool is_package_new(int package) { struct rapl_package *rp; /* caller prevents cpu hotplug, there will be no new packages added * or deleted while traversing the package list, no need for locking. */ list_for_each_entry(rp, &rapl_packages, plist) if (package == rp->id) return false; return true; } /* RAPL interface can be made of a two-level hierarchy: package level and domain * level. We first detect the number of packages then domains of each package. * We have to consider the possiblity of CPU online/offline due to hotplug and * other scenarios. */ static int rapl_detect_topology(void) { int i; int phy_package_id; struct rapl_package *new_package, *rp; for_each_online_cpu(i) { phy_package_id = topology_physical_package_id(i); if (is_package_new(phy_package_id)) { new_package = kzalloc(sizeof(*rp), GFP_KERNEL); if (!new_package) { rapl_cleanup_data(); return -ENOMEM; } /* add the new package to the list */ new_package->id = phy_package_id; new_package->nr_cpus = 1; /* check if the package contains valid domains */ if (rapl_detect_domains(new_package, i) || rapl_check_unit(new_package, i)) { kfree(new_package->domains); kfree(new_package); /* free up the packages already initialized */ rapl_cleanup_data(); return -ENODEV; } INIT_LIST_HEAD(&new_package->plist); list_add(&new_package->plist, &rapl_packages); } else { rp = find_package_by_id(phy_package_id); if (rp) ++rp->nr_cpus; } } return 0; } /* called from CPU hotplug notifier, hotplug lock held */ static void rapl_remove_package(struct rapl_package *rp) { struct rapl_domain *rd, *rd_package = NULL; for (rd = rp->domains; rd < rp->domains + rp->nr_domains; rd++) { if (rd->id == RAPL_DOMAIN_PACKAGE) { rd_package = rd; continue; } pr_debug("remove package %d, %s domain\n", rp->id, rd->name); powercap_unregister_zone(control_type, &rd->power_zone); } /* do parent zone last */ powercap_unregister_zone(control_type, &rd_package->power_zone); list_del(&rp->plist); kfree(rp); } /* called from CPU hotplug notifier, hotplug lock held */ static int rapl_add_package(int cpu) { int ret = 0; int phy_package_id; struct rapl_package *rp; phy_package_id = topology_physical_package_id(cpu); rp = kzalloc(sizeof(struct rapl_package), GFP_KERNEL); if (!rp) return -ENOMEM; /* add the new package to the list */ rp->id = phy_package_id; rp->nr_cpus = 1; /* check if the package contains valid domains */ if (rapl_detect_domains(rp, cpu) || rapl_check_unit(rp, cpu)) { ret = -ENODEV; goto err_free_package; } if (!rapl_package_register_powercap(rp)) { INIT_LIST_HEAD(&rp->plist); list_add(&rp->plist, &rapl_packages); return ret; } err_free_package: kfree(rp->domains); kfree(rp); return ret; } /* Handles CPU hotplug on multi-socket systems. * If a CPU goes online as the first CPU of the physical package * we add the RAPL package to the system. Similarly, when the last * CPU of the package is removed, we remove the RAPL package and its * associated domains. Cooling devices are handled accordingly at * per-domain level. */ static int rapl_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu) { unsigned long cpu = (unsigned long)hcpu; int phy_package_id; struct rapl_package *rp; phy_package_id = topology_physical_package_id(cpu); switch (action) { case CPU_ONLINE: case CPU_ONLINE_FROZEN: case CPU_DOWN_FAILED: case CPU_DOWN_FAILED_FROZEN: rp = find_package_by_id(phy_package_id); if (rp) ++rp->nr_cpus; else rapl_add_package(cpu); break; case CPU_DOWN_PREPARE: case CPU_DOWN_PREPARE_FROZEN: rp = find_package_by_id(phy_package_id); if (!rp) break; if (--rp->nr_cpus == 0) rapl_remove_package(rp); } return NOTIFY_OK; } static struct notifier_block rapl_cpu_notifier = { .notifier_call = rapl_cpu_callback, }; static int __init rapl_init(void) { int ret = 0; if (!x86_match_cpu(rapl_ids)) { pr_err("driver does not support CPU family %d model %d\n", boot_cpu_data.x86, boot_cpu_data.x86_model); return -ENODEV; } cpu_notifier_register_begin(); /* prevent CPU hotplug during detection */ get_online_cpus(); ret = rapl_detect_topology(); if (ret) goto done; if (rapl_register_powercap()) { rapl_cleanup_data(); ret = -ENODEV; goto done; } __register_hotcpu_notifier(&rapl_cpu_notifier); done: put_online_cpus(); cpu_notifier_register_done(); return ret; } static void __exit rapl_exit(void) { cpu_notifier_register_begin(); get_online_cpus(); __unregister_hotcpu_notifier(&rapl_cpu_notifier); rapl_unregister_powercap(); rapl_cleanup_data(); put_online_cpus(); cpu_notifier_register_done(); } module_init(rapl_init); module_exit(rapl_exit); MODULE_DESCRIPTION("Driver for Intel RAPL (Running Average Power Limit)"); MODULE_AUTHOR("Jacob Pan "); MODULE_LICENSE("GPL v2");