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/cpu_device_id.h>
26#include <asm/intel-family.h>
27
28/* Local defines */
29#define MSR_PLATFORM_POWER_LIMIT 0x0000065C
30#define MSR_VR_CURRENT_CONFIG 0x00000601
31
32/* private data for RAPL MSR Interface */
33static struct rapl_if_priv *rapl_msr_priv;
34
35static struct rapl_if_priv rapl_msr_priv_intel = {
36 .type = RAPL_IF_MSR,
37 .reg_unit.msr = MSR_RAPL_POWER_UNIT,
38 .regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_LIMIT].msr = MSR_PKG_POWER_LIMIT,
39 .regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_STATUS].msr = MSR_PKG_ENERGY_STATUS,
40 .regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_PERF].msr = MSR_PKG_PERF_STATUS,
41 .regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_INFO].msr = MSR_PKG_POWER_INFO,
42 .regs[RAPL_DOMAIN_PP0][RAPL_DOMAIN_REG_LIMIT].msr = MSR_PP0_POWER_LIMIT,
43 .regs[RAPL_DOMAIN_PP0][RAPL_DOMAIN_REG_STATUS].msr = MSR_PP0_ENERGY_STATUS,
44 .regs[RAPL_DOMAIN_PP0][RAPL_DOMAIN_REG_POLICY].msr = MSR_PP0_POLICY,
45 .regs[RAPL_DOMAIN_PP1][RAPL_DOMAIN_REG_LIMIT].msr = MSR_PP1_POWER_LIMIT,
46 .regs[RAPL_DOMAIN_PP1][RAPL_DOMAIN_REG_STATUS].msr = MSR_PP1_ENERGY_STATUS,
47 .regs[RAPL_DOMAIN_PP1][RAPL_DOMAIN_REG_POLICY].msr = MSR_PP1_POLICY,
48 .regs[RAPL_DOMAIN_DRAM][RAPL_DOMAIN_REG_LIMIT].msr = MSR_DRAM_POWER_LIMIT,
49 .regs[RAPL_DOMAIN_DRAM][RAPL_DOMAIN_REG_STATUS].msr = MSR_DRAM_ENERGY_STATUS,
50 .regs[RAPL_DOMAIN_DRAM][RAPL_DOMAIN_REG_PERF].msr = MSR_DRAM_PERF_STATUS,
51 .regs[RAPL_DOMAIN_DRAM][RAPL_DOMAIN_REG_INFO].msr = MSR_DRAM_POWER_INFO,
52 .regs[RAPL_DOMAIN_PLATFORM][RAPL_DOMAIN_REG_LIMIT].msr = MSR_PLATFORM_POWER_LIMIT,
53 .regs[RAPL_DOMAIN_PLATFORM][RAPL_DOMAIN_REG_STATUS].msr = MSR_PLATFORM_ENERGY_STATUS,
54 .limits[RAPL_DOMAIN_PACKAGE] = BIT(POWER_LIMIT2),
55 .limits[RAPL_DOMAIN_PLATFORM] = BIT(POWER_LIMIT2),
56};
57
58static struct rapl_if_priv rapl_msr_priv_amd = {
59 .type = RAPL_IF_MSR,
60 .reg_unit.msr = MSR_AMD_RAPL_POWER_UNIT,
61 .regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_STATUS].msr = MSR_AMD_PKG_ENERGY_STATUS,
62 .regs[RAPL_DOMAIN_PP0][RAPL_DOMAIN_REG_STATUS].msr = MSR_AMD_CORE_ENERGY_STATUS,
63};
64
65/* Handles CPU hotplug on multi-socket systems.
66 * If a CPU goes online as the first CPU of the physical package
67 * we add the RAPL package to the system. Similarly, when the last
68 * CPU of the package is removed, we remove the RAPL package and its
69 * associated domains. Cooling devices are handled accordingly at
70 * per-domain level.
71 */
72static int rapl_cpu_online(unsigned int cpu)
73{
74 struct rapl_package *rp;
75
76 rp = rapl_find_package_domain_cpuslocked(id: cpu, priv: rapl_msr_priv, id_is_cpu: true);
77 if (!rp) {
78 rp = rapl_add_package_cpuslocked(id: cpu, priv: rapl_msr_priv, id_is_cpu: true);
79 if (IS_ERR(ptr: rp))
80 return PTR_ERR(ptr: rp);
81 }
82 cpumask_set_cpu(cpu, dstp: &rp->cpumask);
83 return 0;
84}
85
86static int rapl_cpu_down_prep(unsigned int cpu)
87{
88 struct rapl_package *rp;
89 int lead_cpu;
90
91 rp = rapl_find_package_domain_cpuslocked(id: cpu, priv: rapl_msr_priv, id_is_cpu: true);
92 if (!rp)
93 return 0;
94
95 cpumask_clear_cpu(cpu, dstp: &rp->cpumask);
96 lead_cpu = cpumask_first(srcp: &rp->cpumask);
97 if (lead_cpu >= nr_cpu_ids)
98 rapl_remove_package_cpuslocked(rp);
99 else if (rp->lead_cpu == cpu)
100 rp->lead_cpu = lead_cpu;
101 return 0;
102}
103
104static int rapl_msr_read_raw(int cpu, struct reg_action *ra)
105{
106 if (rdmsrl_safe_on_cpu(cpu, msr_no: ra->reg.msr, q: &ra->value)) {
107 pr_debug("failed to read msr 0x%x on cpu %d\n", ra->reg.msr, cpu);
108 return -EIO;
109 }
110 ra->value &= ra->mask;
111 return 0;
112}
113
114static void rapl_msr_update_func(void *info)
115{
116 struct reg_action *ra = info;
117 u64 val;
118
119 ra->err = rdmsrl_safe(msr: ra->reg.msr, p: &val);
120 if (ra->err)
121 return;
122
123 val &= ~ra->mask;
124 val |= ra->value;
125
126 ra->err = wrmsrl_safe(msr: ra->reg.msr, val);
127}
128
129static int rapl_msr_write_raw(int cpu, struct reg_action *ra)
130{
131 int ret;
132
133 ret = smp_call_function_single(cpuid: cpu, func: rapl_msr_update_func, info: ra, wait: 1);
134 if (WARN_ON_ONCE(ret))
135 return ret;
136
137 return ra->err;
138}
139
140/* List of verified CPUs. */
141static const struct x86_cpu_id pl4_support_ids[] = {
142 X86_MATCH_INTEL_FAM6_MODEL(TIGERLAKE_L, NULL),
143 X86_MATCH_INTEL_FAM6_MODEL(ALDERLAKE, NULL),
144 X86_MATCH_INTEL_FAM6_MODEL(ALDERLAKE_L, NULL),
145 X86_MATCH_INTEL_FAM6_MODEL(ATOM_GRACEMONT, NULL),
146 X86_MATCH_INTEL_FAM6_MODEL(RAPTORLAKE, NULL),
147 X86_MATCH_INTEL_FAM6_MODEL(RAPTORLAKE_P, NULL),
148 X86_MATCH_INTEL_FAM6_MODEL(METEORLAKE, NULL),
149 X86_MATCH_INTEL_FAM6_MODEL(METEORLAKE_L, NULL),
150 {}
151};
152
153static int rapl_msr_probe(struct platform_device *pdev)
154{
155 const struct x86_cpu_id *id = x86_match_cpu(match: pl4_support_ids);
156 int ret;
157
158 switch (boot_cpu_data.x86_vendor) {
159 case X86_VENDOR_INTEL:
160 rapl_msr_priv = &rapl_msr_priv_intel;
161 break;
162 case X86_VENDOR_HYGON:
163 case X86_VENDOR_AMD:
164 rapl_msr_priv = &rapl_msr_priv_amd;
165 break;
166 default:
167 pr_err("intel-rapl does not support CPU vendor %d\n", boot_cpu_data.x86_vendor);
168 return -ENODEV;
169 }
170 rapl_msr_priv->read_raw = rapl_msr_read_raw;
171 rapl_msr_priv->write_raw = rapl_msr_write_raw;
172
173 if (id) {
174 rapl_msr_priv->limits[RAPL_DOMAIN_PACKAGE] |= BIT(POWER_LIMIT4);
175 rapl_msr_priv->regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_PL4].msr =
176 MSR_VR_CURRENT_CONFIG;
177 pr_info("PL4 support detected.\n");
178 }
179
180 rapl_msr_priv->control_type = powercap_register_control_type(NULL, name: "intel-rapl", NULL);
181 if (IS_ERR(ptr: rapl_msr_priv->control_type)) {
182 pr_debug("failed to register powercap control_type.\n");
183 return PTR_ERR(ptr: rapl_msr_priv->control_type);
184 }
185
186 ret = cpuhp_setup_state(state: CPUHP_AP_ONLINE_DYN, name: "powercap/rapl:online",
187 startup: rapl_cpu_online, teardown: rapl_cpu_down_prep);
188 if (ret < 0)
189 goto out;
190 rapl_msr_priv->pcap_rapl_online = ret;
191
192 return 0;
193
194out:
195 if (ret)
196 powercap_unregister_control_type(instance: rapl_msr_priv->control_type);
197 return ret;
198}
199
200static void rapl_msr_remove(struct platform_device *pdev)
201{
202 cpuhp_remove_state(state: rapl_msr_priv->pcap_rapl_online);
203 powercap_unregister_control_type(instance: rapl_msr_priv->control_type);
204}
205
206static const struct platform_device_id rapl_msr_ids[] = {
207 { .name = "intel_rapl_msr", },
208 {}
209};
210MODULE_DEVICE_TABLE(platform, rapl_msr_ids);
211
212static struct platform_driver intel_rapl_msr_driver = {
213 .probe = rapl_msr_probe,
214 .remove_new = rapl_msr_remove,
215 .id_table = rapl_msr_ids,
216 .driver = {
217 .name = "intel_rapl_msr",
218 },
219};
220
221module_platform_driver(intel_rapl_msr_driver);
222
223MODULE_DESCRIPTION("Driver for Intel RAPL (Running Average Power Limit) control via MSR interface");
224MODULE_AUTHOR("Zhang Rui <rui.zhang@intel.com>");
225MODULE_LICENSE("GPL v2");
226

source code of linux/drivers/powercap/intel_rapl_msr.c