1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Mapping of TPMI power domains CPU mapping
4 *
5 * Copyright (c) 2024, Intel Corporation.
6 */
7
8 #include <linux/bitfield.h>
9 #include <linux/cleanup.h>
10 #include <linux/cpuhotplug.h>
11 #include <linux/cpumask.h>
12 #include <linux/errno.h>
13 #include <linux/export.h>
14 #include <linux/hashtable.h>
15 #include <linux/module.h>
16 #include <linux/mutex.h>
17 #include <linux/overflow.h>
18 #include <linux/slab.h>
19 #include <linux/topology.h>
20 #include <linux/types.h>
21
22 #include <asm/cpu_device_id.h>
23 #include <asm/intel-family.h>
24 #include <asm/msr.h>
25
26 #include "tpmi_power_domains.h"
27
28 #define MSR_PM_LOGICAL_ID 0x54
29
30 /*
31 * Struct of MSR 0x54
32 * [15:11] PM_DOMAIN_ID
33 * [10:3] MODULE_ID (aka IDI_AGENT_ID)
34 * [2:0] LP_ID
35 * For Atom:
36 * [2] Always 0
37 * [1:0] core ID within module
38 * For Core
39 * [2:1] Always 0
40 * [0] thread ID
41 */
42
43 #define LP_ID_MASK GENMASK_ULL(2, 0)
44 #define MODULE_ID_MASK GENMASK_ULL(10, 3)
45 #define PM_DOMAIN_ID_MASK GENMASK_ULL(15, 11)
46
47 /**
48 * struct tpmi_cpu_info - Mapping information for a CPU
49 * @hnode: Used to add mapping information to hash list
50 * @linux_cpu: Linux CPU number
51 * @pkg_id: Package ID of this CPU
52 * @punit_thread_id: Punit thread id of this CPU
53 * @punit_core_id: Punit core id
54 * @punit_domain_id: Power domain id from Punit
55 *
56 * Structure to store mapping information for a Linux CPU
57 * to a Punit core, thread and power domain.
58 */
59 struct tpmi_cpu_info {
60 struct hlist_node hnode;
61 int linux_cpu;
62 u8 pkg_id;
63 u8 punit_thread_id;
64 u8 punit_core_id;
65 u8 punit_domain_id;
66 };
67
68 static DEFINE_PER_CPU(struct tpmi_cpu_info, tpmi_cpu_info);
69
70 /* The dynamically assigned cpu hotplug state to free later */
71 static enum cpuhp_state tpmi_hp_state __read_mostly;
72
73 #define MAX_POWER_DOMAINS 8
74
75 static cpumask_t *tpmi_power_domain_mask;
76
77 /* Lock to protect tpmi_power_domain_mask and tpmi_cpu_hash */
78 static DEFINE_MUTEX(tpmi_lock);
79
80 static const struct x86_cpu_id tpmi_cpu_ids[] = {
81 X86_MATCH_VFM(INTEL_GRANITERAPIDS_X, NULL),
82 X86_MATCH_VFM(INTEL_ATOM_CRESTMONT_X, NULL),
83 X86_MATCH_VFM(INTEL_ATOM_CRESTMONT, NULL),
84 X86_MATCH_VFM(INTEL_GRANITERAPIDS_D, NULL),
85 X86_MATCH_VFM(INTEL_PANTHERCOVE_X, NULL),
86 {}
87 };
88 MODULE_DEVICE_TABLE(x86cpu, tpmi_cpu_ids);
89
90 static DECLARE_HASHTABLE(tpmi_cpu_hash, 8);
91
tpmi_domain_is_valid(struct tpmi_cpu_info * info)92 static bool tpmi_domain_is_valid(struct tpmi_cpu_info *info)
93 {
94 return info->pkg_id < topology_max_packages() &&
95 info->punit_domain_id < MAX_POWER_DOMAINS;
96 }
97
tpmi_get_linux_cpu_number(int package_id,int domain_id,int punit_core_id)98 int tpmi_get_linux_cpu_number(int package_id, int domain_id, int punit_core_id)
99 {
100 struct tpmi_cpu_info *info;
101 int ret = -EINVAL;
102
103 guard(mutex)(&tpmi_lock);
104 hash_for_each_possible(tpmi_cpu_hash, info, hnode, punit_core_id) {
105 if (info->punit_domain_id == domain_id && info->pkg_id == package_id) {
106 ret = info->linux_cpu;
107 break;
108 }
109 }
110
111 return ret;
112 }
113 EXPORT_SYMBOL_NS_GPL(tpmi_get_linux_cpu_number, "INTEL_TPMI_POWER_DOMAIN");
114
tpmi_get_punit_core_number(int cpu_no)115 int tpmi_get_punit_core_number(int cpu_no)
116 {
117 if (cpu_no >= num_possible_cpus())
118 return -EINVAL;
119
120 return per_cpu(tpmi_cpu_info, cpu_no).punit_core_id;
121 }
122 EXPORT_SYMBOL_NS_GPL(tpmi_get_punit_core_number, "INTEL_TPMI_POWER_DOMAIN");
123
tpmi_get_power_domain_id(int cpu_no)124 int tpmi_get_power_domain_id(int cpu_no)
125 {
126 if (cpu_no >= num_possible_cpus())
127 return -EINVAL;
128
129 return per_cpu(tpmi_cpu_info, cpu_no).punit_domain_id;
130 }
131 EXPORT_SYMBOL_NS_GPL(tpmi_get_power_domain_id, "INTEL_TPMI_POWER_DOMAIN");
132
tpmi_get_power_domain_mask(int cpu_no)133 cpumask_t *tpmi_get_power_domain_mask(int cpu_no)
134 {
135 struct tpmi_cpu_info *info;
136 cpumask_t *mask;
137 int index;
138
139 if (cpu_no >= num_possible_cpus())
140 return NULL;
141
142 info = &per_cpu(tpmi_cpu_info, cpu_no);
143 if (!tpmi_domain_is_valid(info))
144 return NULL;
145
146 index = info->pkg_id * MAX_POWER_DOMAINS + info->punit_domain_id;
147 guard(mutex)(&tpmi_lock);
148 mask = &tpmi_power_domain_mask[index];
149
150 return mask;
151 }
152 EXPORT_SYMBOL_NS_GPL(tpmi_get_power_domain_mask, "INTEL_TPMI_POWER_DOMAIN");
153
tpmi_get_logical_id(unsigned int cpu,struct tpmi_cpu_info * info)154 static int tpmi_get_logical_id(unsigned int cpu, struct tpmi_cpu_info *info)
155 {
156 u64 data;
157 int ret;
158
159 ret = rdmsrl_safe(MSR_PM_LOGICAL_ID, &data);
160 if (ret)
161 return ret;
162
163 info->punit_domain_id = FIELD_GET(PM_DOMAIN_ID_MASK, data);
164 if (info->punit_domain_id >= MAX_POWER_DOMAINS)
165 return -EINVAL;
166
167 info->punit_thread_id = FIELD_GET(LP_ID_MASK, data);
168 info->punit_core_id = FIELD_GET(MODULE_ID_MASK, data);
169 info->pkg_id = topology_physical_package_id(cpu);
170 info->linux_cpu = cpu;
171
172 return 0;
173 }
174
tpmi_cpu_online(unsigned int cpu)175 static int tpmi_cpu_online(unsigned int cpu)
176 {
177 struct tpmi_cpu_info *info = &per_cpu(tpmi_cpu_info, cpu);
178 int ret, index;
179
180 /* Don't fail CPU online for some bad mapping of CPUs */
181 ret = tpmi_get_logical_id(cpu, info);
182 if (ret)
183 return 0;
184
185 index = info->pkg_id * MAX_POWER_DOMAINS + info->punit_domain_id;
186
187 guard(mutex)(&tpmi_lock);
188 cpumask_set_cpu(cpu, &tpmi_power_domain_mask[index]);
189 hash_add(tpmi_cpu_hash, &info->hnode, info->punit_core_id);
190
191 return 0;
192 }
193
tpmi_init(void)194 static int __init tpmi_init(void)
195 {
196 const struct x86_cpu_id *id;
197 u64 data;
198 int ret;
199
200 id = x86_match_cpu(tpmi_cpu_ids);
201 if (!id)
202 return -ENODEV;
203
204 /* Check for MSR 0x54 presence */
205 ret = rdmsrl_safe(MSR_PM_LOGICAL_ID, &data);
206 if (ret)
207 return ret;
208
209 tpmi_power_domain_mask = kcalloc(size_mul(topology_max_packages(), MAX_POWER_DOMAINS),
210 sizeof(*tpmi_power_domain_mask), GFP_KERNEL);
211 if (!tpmi_power_domain_mask)
212 return -ENOMEM;
213
214 ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
215 "platform/x86/tpmi_power_domains:online",
216 tpmi_cpu_online, NULL);
217 if (ret < 0) {
218 kfree(tpmi_power_domain_mask);
219 return ret;
220 }
221
222 tpmi_hp_state = ret;
223
224 return 0;
225 }
module_init(tpmi_init)226 module_init(tpmi_init)
227
228 static void __exit tpmi_exit(void)
229 {
230 cpuhp_remove_state(tpmi_hp_state);
231 kfree(tpmi_power_domain_mask);
232 }
233 module_exit(tpmi_exit)
234
235 MODULE_DESCRIPTION("TPMI Power Domains Mapping");
236 MODULE_LICENSE("GPL");
237