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(cpu, rapl_msr_priv, true);
77	if (!rp) {
78		rp = rapl_add_package_cpuslocked(cpu, rapl_msr_priv, true);
79		if (IS_ERR(rp))
80			return PTR_ERR(rp);
81	}
82	cpumask_set_cpu(cpu, &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(cpu, rapl_msr_priv, true);
92	if (!rp)
93		return 0;
94
95	cpumask_clear_cpu(cpu, &rp->cpumask);
96	lead_cpu = cpumask_first(&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, ra->reg.msr, &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(ra->reg.msr, &val);
120	if (ra->err)
121		return;
122
123	val &= ~ra->mask;
124	val |= ra->value;
125
126	ra->err = wrmsrl_safe(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(cpu, rapl_msr_update_func, ra, 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(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, "intel-rapl", NULL);
181	if (IS_ERR(rapl_msr_priv->control_type)) {
182		pr_debug("failed to register powercap control_type.\n");
183		return PTR_ERR(rapl_msr_priv->control_type);
184	}
185
186	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "powercap/rapl:online",
187				rapl_cpu_online, 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(rapl_msr_priv->control_type);
197	return ret;
198}
199
200static int rapl_msr_remove(struct platform_device *pdev)
201{
202	cpuhp_remove_state(rapl_msr_priv->pcap_rapl_online);
203	powercap_unregister_control_type(rapl_msr_priv->control_type);
204	return 0;
205}
206
207static const struct platform_device_id rapl_msr_ids[] = {
208	{ .name = "intel_rapl_msr", },
209	{}
210};
211MODULE_DEVICE_TABLE(platform, rapl_msr_ids);
212
213static struct platform_driver intel_rapl_msr_driver = {
214	.probe = rapl_msr_probe,
215	.remove = rapl_msr_remove,
216	.id_table = rapl_msr_ids,
217	.driver = {
218		.name = "intel_rapl_msr",
219	},
220};
221
222module_platform_driver(intel_rapl_msr_driver);
223
224MODULE_DESCRIPTION("Driver for Intel RAPL (Running Average Power Limit) control via MSR interface");
225MODULE_AUTHOR("Zhang Rui <rui.zhang@intel.com>");
226MODULE_LICENSE("GPL v2");
227