xref: /linux/drivers/powercap/intel_rapl_msr.c (revision 7fc2cd2e4b398c57c9cf961cfea05eadbf34c05c)
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 #include <asm/msr.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 bool rapl_msr_pmu __ro_after_init;
37 
38 static struct rapl_if_priv rapl_msr_priv_intel = {
39 	.type = RAPL_IF_MSR,
40 	.reg_unit.msr = MSR_RAPL_POWER_UNIT,
41 	.regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_LIMIT].msr	= MSR_PKG_POWER_LIMIT,
42 	.regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_STATUS].msr	= MSR_PKG_ENERGY_STATUS,
43 	.regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_PERF].msr	= MSR_PKG_PERF_STATUS,
44 	.regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_INFO].msr	= MSR_PKG_POWER_INFO,
45 	.regs[RAPL_DOMAIN_PP0][RAPL_DOMAIN_REG_LIMIT].msr	= MSR_PP0_POWER_LIMIT,
46 	.regs[RAPL_DOMAIN_PP0][RAPL_DOMAIN_REG_STATUS].msr	= MSR_PP0_ENERGY_STATUS,
47 	.regs[RAPL_DOMAIN_PP0][RAPL_DOMAIN_REG_POLICY].msr	= MSR_PP0_POLICY,
48 	.regs[RAPL_DOMAIN_PP1][RAPL_DOMAIN_REG_LIMIT].msr	= MSR_PP1_POWER_LIMIT,
49 	.regs[RAPL_DOMAIN_PP1][RAPL_DOMAIN_REG_STATUS].msr	= MSR_PP1_ENERGY_STATUS,
50 	.regs[RAPL_DOMAIN_PP1][RAPL_DOMAIN_REG_POLICY].msr	= MSR_PP1_POLICY,
51 	.regs[RAPL_DOMAIN_DRAM][RAPL_DOMAIN_REG_LIMIT].msr	= MSR_DRAM_POWER_LIMIT,
52 	.regs[RAPL_DOMAIN_DRAM][RAPL_DOMAIN_REG_STATUS].msr	= MSR_DRAM_ENERGY_STATUS,
53 	.regs[RAPL_DOMAIN_DRAM][RAPL_DOMAIN_REG_PERF].msr	= MSR_DRAM_PERF_STATUS,
54 	.regs[RAPL_DOMAIN_DRAM][RAPL_DOMAIN_REG_INFO].msr	= MSR_DRAM_POWER_INFO,
55 	.regs[RAPL_DOMAIN_PLATFORM][RAPL_DOMAIN_REG_LIMIT].msr	= MSR_PLATFORM_POWER_LIMIT,
56 	.regs[RAPL_DOMAIN_PLATFORM][RAPL_DOMAIN_REG_STATUS].msr	= MSR_PLATFORM_ENERGY_STATUS,
57 	.limits[RAPL_DOMAIN_PACKAGE] = BIT(POWER_LIMIT2),
58 	.limits[RAPL_DOMAIN_PLATFORM] = BIT(POWER_LIMIT2),
59 };
60 
61 static struct rapl_if_priv rapl_msr_priv_amd = {
62 	.type = RAPL_IF_MSR,
63 	.reg_unit.msr = MSR_AMD_RAPL_POWER_UNIT,
64 	.regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_STATUS].msr	= MSR_AMD_PKG_ENERGY_STATUS,
65 	.regs[RAPL_DOMAIN_PP0][RAPL_DOMAIN_REG_STATUS].msr	= MSR_AMD_CORE_ENERGY_STATUS,
66 };
67 
68 /* Handles CPU hotplug on multi-socket systems.
69  * If a CPU goes online as the first CPU of the physical package
70  * we add the RAPL package to the system. Similarly, when the last
71  * CPU of the package is removed, we remove the RAPL package and its
72  * associated domains. Cooling devices are handled accordingly at
73  * per-domain level.
74  */
75 static int rapl_cpu_online(unsigned int cpu)
76 {
77 	struct rapl_package *rp;
78 
79 	rp = rapl_find_package_domain_cpuslocked(cpu, rapl_msr_priv, true);
80 	if (!rp) {
81 		rp = rapl_add_package_cpuslocked(cpu, rapl_msr_priv, true);
82 		if (IS_ERR(rp))
83 			return PTR_ERR(rp);
84 		if (rapl_msr_pmu)
85 			rapl_package_add_pmu(rp);
86 	}
87 	cpumask_set_cpu(cpu, &rp->cpumask);
88 	return 0;
89 }
90 
91 static int rapl_cpu_down_prep(unsigned int cpu)
92 {
93 	struct rapl_package *rp;
94 	int lead_cpu;
95 
96 	rp = rapl_find_package_domain_cpuslocked(cpu, rapl_msr_priv, true);
97 	if (!rp)
98 		return 0;
99 
100 	cpumask_clear_cpu(cpu, &rp->cpumask);
101 	lead_cpu = cpumask_first(&rp->cpumask);
102 	if (lead_cpu >= nr_cpu_ids) {
103 		if (rapl_msr_pmu)
104 			rapl_package_remove_pmu(rp);
105 		rapl_remove_package_cpuslocked(rp);
106 	} else if (rp->lead_cpu == cpu) {
107 		rp->lead_cpu = lead_cpu;
108 	}
109 
110 	return 0;
111 }
112 
113 static int rapl_msr_read_raw(int cpu, struct reg_action *ra, bool atomic)
114 {
115 	/*
116 	 * When called from atomic-context (eg PMU event handler)
117 	 * perform MSR read directly using rdmsrq().
118 	 */
119 	if (atomic) {
120 		if (unlikely(smp_processor_id() != cpu))
121 			return -EIO;
122 
123 		rdmsrq(ra->reg.msr, ra->value);
124 		goto out;
125 	}
126 
127 	if (rdmsrq_safe_on_cpu(cpu, ra->reg.msr, &ra->value)) {
128 		pr_debug("failed to read msr 0x%x on cpu %d\n", ra->reg.msr, cpu);
129 		return -EIO;
130 	}
131 
132 out:
133 	ra->value &= ra->mask;
134 	return 0;
135 }
136 
137 static void rapl_msr_update_func(void *info)
138 {
139 	struct reg_action *ra = info;
140 	u64 val;
141 
142 	ra->err = rdmsrq_safe(ra->reg.msr, &val);
143 	if (ra->err)
144 		return;
145 
146 	val &= ~ra->mask;
147 	val |= ra->value;
148 
149 	ra->err = wrmsrq_safe(ra->reg.msr, val);
150 }
151 
152 static int rapl_msr_write_raw(int cpu, struct reg_action *ra)
153 {
154 	int ret;
155 
156 	ret = smp_call_function_single(cpu, rapl_msr_update_func, ra, 1);
157 	if (WARN_ON_ONCE(ret))
158 		return ret;
159 
160 	return ra->err;
161 }
162 
163 /* List of verified CPUs. */
164 static const struct x86_cpu_id pl4_support_ids[] = {
165 	X86_MATCH_VFM(INTEL_TIGERLAKE_L, NULL),
166 	X86_MATCH_VFM(INTEL_ALDERLAKE, NULL),
167 	X86_MATCH_VFM(INTEL_ALDERLAKE_L, NULL),
168 	X86_MATCH_VFM(INTEL_ATOM_GRACEMONT, NULL),
169 	X86_MATCH_VFM(INTEL_RAPTORLAKE, NULL),
170 	X86_MATCH_VFM(INTEL_RAPTORLAKE_P, NULL),
171 	X86_MATCH_VFM(INTEL_METEORLAKE, NULL),
172 	X86_MATCH_VFM(INTEL_METEORLAKE_L, NULL),
173 	X86_MATCH_VFM(INTEL_ARROWLAKE_U, NULL),
174 	X86_MATCH_VFM(INTEL_ARROWLAKE_H, NULL),
175 	X86_MATCH_VFM(INTEL_PANTHERLAKE_L, NULL),
176 	X86_MATCH_VFM(INTEL_WILDCATLAKE_L, NULL),
177 	X86_MATCH_VFM(INTEL_NOVALAKE, NULL),
178 	X86_MATCH_VFM(INTEL_NOVALAKE_L, NULL),
179 	{}
180 };
181 
182 /* List of MSR-based RAPL PMU support CPUs */
183 static const struct x86_cpu_id pmu_support_ids[] = {
184 	X86_MATCH_VFM(INTEL_PANTHERLAKE_L, NULL),
185 	X86_MATCH_VFM(INTEL_WILDCATLAKE_L, NULL),
186 	{}
187 };
188 
189 static int rapl_msr_probe(struct platform_device *pdev)
190 {
191 	const struct x86_cpu_id *id = x86_match_cpu(pl4_support_ids);
192 	int ret;
193 
194 	switch (boot_cpu_data.x86_vendor) {
195 	case X86_VENDOR_INTEL:
196 		rapl_msr_priv = &rapl_msr_priv_intel;
197 		break;
198 	case X86_VENDOR_HYGON:
199 	case X86_VENDOR_AMD:
200 		rapl_msr_priv = &rapl_msr_priv_amd;
201 		break;
202 	default:
203 		pr_err("intel-rapl does not support CPU vendor %d\n", boot_cpu_data.x86_vendor);
204 		return -ENODEV;
205 	}
206 	rapl_msr_priv->read_raw = rapl_msr_read_raw;
207 	rapl_msr_priv->write_raw = rapl_msr_write_raw;
208 
209 	if (id) {
210 		rapl_msr_priv->limits[RAPL_DOMAIN_PACKAGE] |= BIT(POWER_LIMIT4);
211 		rapl_msr_priv->regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_PL4].msr =
212 			MSR_VR_CURRENT_CONFIG;
213 		pr_info("PL4 support detected.\n");
214 	}
215 
216 	if (x86_match_cpu(pmu_support_ids)) {
217 		rapl_msr_pmu = true;
218 		pr_info("MSR-based RAPL PMU support enabled\n");
219 	}
220 
221 	rapl_msr_priv->control_type = powercap_register_control_type(NULL, "intel-rapl", NULL);
222 	if (IS_ERR(rapl_msr_priv->control_type)) {
223 		pr_debug("failed to register powercap control_type.\n");
224 		return PTR_ERR(rapl_msr_priv->control_type);
225 	}
226 
227 	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "powercap/rapl:online",
228 				rapl_cpu_online, rapl_cpu_down_prep);
229 	if (ret < 0)
230 		goto out;
231 	rapl_msr_priv->pcap_rapl_online = ret;
232 
233 	return 0;
234 
235 out:
236 	if (ret)
237 		powercap_unregister_control_type(rapl_msr_priv->control_type);
238 	return ret;
239 }
240 
241 static void rapl_msr_remove(struct platform_device *pdev)
242 {
243 	cpuhp_remove_state(rapl_msr_priv->pcap_rapl_online);
244 	powercap_unregister_control_type(rapl_msr_priv->control_type);
245 }
246 
247 static const struct platform_device_id rapl_msr_ids[] = {
248 	{ .name = "intel_rapl_msr", },
249 	{}
250 };
251 MODULE_DEVICE_TABLE(platform, rapl_msr_ids);
252 
253 static struct platform_driver intel_rapl_msr_driver = {
254 	.probe = rapl_msr_probe,
255 	.remove = rapl_msr_remove,
256 	.id_table = rapl_msr_ids,
257 	.driver = {
258 		.name = "intel_rapl_msr",
259 	},
260 };
261 
262 module_platform_driver(intel_rapl_msr_driver);
263 
264 MODULE_DESCRIPTION("Driver for Intel RAPL (Running Average Power Limit) control via MSR interface");
265 MODULE_AUTHOR("Zhang Rui <rui.zhang@intel.com>");
266 MODULE_LICENSE("GPL v2");
267