1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Intel Running Average Power Limit (RAPL) Driver via MSR interface 4 * Copyright (c) 2019, Intel Corporation. 5 */ 6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 7 8 #include <linux/kernel.h> 9 #include <linux/module.h> 10 #include <linux/list.h> 11 #include <linux/types.h> 12 #include <linux/device.h> 13 #include <linux/slab.h> 14 #include <linux/log2.h> 15 #include <linux/bitmap.h> 16 #include <linux/delay.h> 17 #include <linux/sysfs.h> 18 #include <linux/cpu.h> 19 #include <linux/powercap.h> 20 #include <linux/suspend.h> 21 #include <linux/intel_rapl.h> 22 #include <linux/processor.h> 23 #include <linux/platform_device.h> 24 25 #include <asm/iosf_mbi.h> 26 #include <asm/cpu_device_id.h> 27 #include <asm/intel-family.h> 28 29 /* Local defines */ 30 #define MSR_PLATFORM_POWER_LIMIT 0x0000065C 31 #define MSR_VR_CURRENT_CONFIG 0x00000601 32 33 /* private data for RAPL MSR Interface */ 34 static struct rapl_if_priv *rapl_msr_priv; 35 36 static struct rapl_if_priv rapl_msr_priv_intel = { 37 .reg_unit = MSR_RAPL_POWER_UNIT, 38 .regs[RAPL_DOMAIN_PACKAGE] = { 39 MSR_PKG_POWER_LIMIT, MSR_PKG_ENERGY_STATUS, MSR_PKG_PERF_STATUS, 0, MSR_PKG_POWER_INFO }, 40 .regs[RAPL_DOMAIN_PP0] = { 41 MSR_PP0_POWER_LIMIT, MSR_PP0_ENERGY_STATUS, 0, MSR_PP0_POLICY, 0 }, 42 .regs[RAPL_DOMAIN_PP1] = { 43 MSR_PP1_POWER_LIMIT, MSR_PP1_ENERGY_STATUS, 0, MSR_PP1_POLICY, 0 }, 44 .regs[RAPL_DOMAIN_DRAM] = { 45 MSR_DRAM_POWER_LIMIT, MSR_DRAM_ENERGY_STATUS, MSR_DRAM_PERF_STATUS, 0, MSR_DRAM_POWER_INFO }, 46 .regs[RAPL_DOMAIN_PLATFORM] = { 47 MSR_PLATFORM_POWER_LIMIT, MSR_PLATFORM_ENERGY_STATUS, 0, 0, 0}, 48 .limits[RAPL_DOMAIN_PACKAGE] = 2, 49 .limits[RAPL_DOMAIN_PLATFORM] = 2, 50 }; 51 52 static struct rapl_if_priv rapl_msr_priv_amd = { 53 .reg_unit = MSR_AMD_RAPL_POWER_UNIT, 54 .regs[RAPL_DOMAIN_PACKAGE] = { 55 0, MSR_AMD_PKG_ENERGY_STATUS, 0, 0, 0 }, 56 .regs[RAPL_DOMAIN_PP0] = { 57 0, MSR_AMD_CORE_ENERGY_STATUS, 0, 0, 0 }, 58 }; 59 60 /* Handles CPU hotplug on multi-socket systems. 61 * If a CPU goes online as the first CPU of the physical package 62 * we add the RAPL package to the system. Similarly, when the last 63 * CPU of the package is removed, we remove the RAPL package and its 64 * associated domains. Cooling devices are handled accordingly at 65 * per-domain level. 66 */ 67 static int rapl_cpu_online(unsigned int cpu) 68 { 69 struct rapl_package *rp; 70 71 rp = rapl_find_package_domain(cpu, rapl_msr_priv); 72 if (!rp) { 73 rp = rapl_add_package(cpu, rapl_msr_priv); 74 if (IS_ERR(rp)) 75 return PTR_ERR(rp); 76 } 77 cpumask_set_cpu(cpu, &rp->cpumask); 78 return 0; 79 } 80 81 static int rapl_cpu_down_prep(unsigned int cpu) 82 { 83 struct rapl_package *rp; 84 int lead_cpu; 85 86 rp = rapl_find_package_domain(cpu, rapl_msr_priv); 87 if (!rp) 88 return 0; 89 90 cpumask_clear_cpu(cpu, &rp->cpumask); 91 lead_cpu = cpumask_first(&rp->cpumask); 92 if (lead_cpu >= nr_cpu_ids) 93 rapl_remove_package(rp); 94 else if (rp->lead_cpu == cpu) 95 rp->lead_cpu = lead_cpu; 96 return 0; 97 } 98 99 static int rapl_msr_read_raw(int cpu, struct reg_action *ra) 100 { 101 u32 msr = (u32)ra->reg; 102 103 if (rdmsrl_safe_on_cpu(cpu, msr, &ra->value)) { 104 pr_debug("failed to read msr 0x%x on cpu %d\n", msr, cpu); 105 return -EIO; 106 } 107 ra->value &= ra->mask; 108 return 0; 109 } 110 111 static void rapl_msr_update_func(void *info) 112 { 113 struct reg_action *ra = info; 114 u32 msr = (u32)ra->reg; 115 u64 val; 116 117 ra->err = rdmsrl_safe(msr, &val); 118 if (ra->err) 119 return; 120 121 val &= ~ra->mask; 122 val |= ra->value; 123 124 ra->err = wrmsrl_safe(msr, val); 125 } 126 127 static int rapl_msr_write_raw(int cpu, struct reg_action *ra) 128 { 129 int ret; 130 131 ret = smp_call_function_single(cpu, rapl_msr_update_func, ra, 1); 132 if (WARN_ON_ONCE(ret)) 133 return ret; 134 135 return ra->err; 136 } 137 138 /* List of verified CPUs. */ 139 static const struct x86_cpu_id pl4_support_ids[] = { 140 { X86_VENDOR_INTEL, 6, INTEL_FAM6_TIGERLAKE_L, X86_FEATURE_ANY }, 141 {} 142 }; 143 144 static int rapl_msr_probe(struct platform_device *pdev) 145 { 146 const struct x86_cpu_id *id = x86_match_cpu(pl4_support_ids); 147 int ret; 148 149 switch (boot_cpu_data.x86_vendor) { 150 case X86_VENDOR_INTEL: 151 rapl_msr_priv = &rapl_msr_priv_intel; 152 break; 153 case X86_VENDOR_HYGON: 154 case X86_VENDOR_AMD: 155 rapl_msr_priv = &rapl_msr_priv_amd; 156 break; 157 default: 158 pr_err("intel-rapl does not support CPU vendor %d\n", boot_cpu_data.x86_vendor); 159 return -ENODEV; 160 } 161 rapl_msr_priv->read_raw = rapl_msr_read_raw; 162 rapl_msr_priv->write_raw = rapl_msr_write_raw; 163 164 if (id) { 165 rapl_msr_priv->limits[RAPL_DOMAIN_PACKAGE] = 3; 166 rapl_msr_priv->regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_PL4] = 167 MSR_VR_CURRENT_CONFIG; 168 pr_info("PL4 support detected.\n"); 169 } 170 171 rapl_msr_priv->control_type = powercap_register_control_type(NULL, "intel-rapl", NULL); 172 if (IS_ERR(rapl_msr_priv->control_type)) { 173 pr_debug("failed to register powercap control_type.\n"); 174 return PTR_ERR(rapl_msr_priv->control_type); 175 } 176 177 ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "powercap/rapl:online", 178 rapl_cpu_online, rapl_cpu_down_prep); 179 if (ret < 0) 180 goto out; 181 rapl_msr_priv->pcap_rapl_online = ret; 182 183 return 0; 184 185 out: 186 if (ret) 187 powercap_unregister_control_type(rapl_msr_priv->control_type); 188 return ret; 189 } 190 191 static int rapl_msr_remove(struct platform_device *pdev) 192 { 193 cpuhp_remove_state(rapl_msr_priv->pcap_rapl_online); 194 powercap_unregister_control_type(rapl_msr_priv->control_type); 195 return 0; 196 } 197 198 static const struct platform_device_id rapl_msr_ids[] = { 199 { .name = "intel_rapl_msr", }, 200 {} 201 }; 202 MODULE_DEVICE_TABLE(platform, rapl_msr_ids); 203 204 static struct platform_driver intel_rapl_msr_driver = { 205 .probe = rapl_msr_probe, 206 .remove = rapl_msr_remove, 207 .id_table = rapl_msr_ids, 208 .driver = { 209 .name = "intel_rapl_msr", 210 }, 211 }; 212 213 module_platform_driver(intel_rapl_msr_driver); 214 215 MODULE_DESCRIPTION("Driver for Intel RAPL (Running Average Power Limit) control via MSR interface"); 216 MODULE_AUTHOR("Zhang Rui <rui.zhang@intel.com>"); 217 MODULE_LICENSE("GPL v2"); 218