tpmi_power_domains.c

  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 */
 59struct 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
 68static DEFINE_PER_CPU(struct tpmi_cpu_info, tpmi_cpu_info);
 69
 70/* The dynamically assigned cpu hotplug state to free later */
 71static enum cpuhp_state tpmi_hp_state __read_mostly;
 72
 73#define MAX_POWER_DOMAINS	8
 74
 75static cpumask_t *tpmi_power_domain_mask;
 76
 77static u16 *domain_die_map;
 78
 79/* Lock to protect tpmi_power_domain_mask and tpmi_cpu_hash */
 80static DEFINE_MUTEX(tpmi_lock);
 81
 82static const struct x86_cpu_id tpmi_cpu_ids[] = {
 83	X86_MATCH_VFM(INTEL_GRANITERAPIDS_X,	NULL),
 84	X86_MATCH_VFM(INTEL_ATOM_CRESTMONT_X,	NULL),
 85	X86_MATCH_VFM(INTEL_ATOM_CRESTMONT,	NULL),
 86	X86_MATCH_VFM(INTEL_ATOM_DARKMONT_X,	NULL),
 87	X86_MATCH_VFM(INTEL_GRANITERAPIDS_D,	NULL),
 88	X86_MATCH_VFM(INTEL_DIAMONDRAPIDS_X,	NULL),
 89	{}
 90};
 91MODULE_DEVICE_TABLE(x86cpu, tpmi_cpu_ids);
 92
 93static DECLARE_HASHTABLE(tpmi_cpu_hash, 8);
 94
 95static bool tpmi_domain_is_valid(struct tpmi_cpu_info *info)
 96{
 97	return info->pkg_id < topology_max_packages() &&
 98		info->punit_domain_id < MAX_POWER_DOMAINS;
 99}
100
101int tpmi_get_linux_cpu_number(int package_id, int domain_id, int punit_core_id)
102{
103	struct tpmi_cpu_info *info;
104	int ret = -EINVAL;
105
106	guard(mutex)(&tpmi_lock);
107	hash_for_each_possible(tpmi_cpu_hash, info, hnode, punit_core_id) {
108		if (info->punit_domain_id == domain_id && info->pkg_id == package_id) {
109			ret = info->linux_cpu;
110			break;
111		}
112	}
113
114	return ret;
115}
116EXPORT_SYMBOL_NS_GPL(tpmi_get_linux_cpu_number, "INTEL_TPMI_POWER_DOMAIN");
117
118int tpmi_get_punit_core_number(int cpu_no)
119{
120	if (cpu_no >= num_possible_cpus())
121		return -EINVAL;
122
123	return per_cpu(tpmi_cpu_info, cpu_no).punit_core_id;
124}
125EXPORT_SYMBOL_NS_GPL(tpmi_get_punit_core_number, "INTEL_TPMI_POWER_DOMAIN");
126
127int tpmi_get_power_domain_id(int cpu_no)
128{
129	if (cpu_no >= num_possible_cpus())
130		return -EINVAL;
131
132	return per_cpu(tpmi_cpu_info, cpu_no).punit_domain_id;
133}
134EXPORT_SYMBOL_NS_GPL(tpmi_get_power_domain_id, "INTEL_TPMI_POWER_DOMAIN");
135
136cpumask_t *tpmi_get_power_domain_mask(int cpu_no)
137{
138	struct tpmi_cpu_info *info;
139	cpumask_t *mask;
140	int index;
141
142	if (cpu_no >= num_possible_cpus())
143		return NULL;
144
145	info = &per_cpu(tpmi_cpu_info, cpu_no);
146	if (!tpmi_domain_is_valid(info))
147		return NULL;
148
149	index = info->pkg_id * MAX_POWER_DOMAINS + info->punit_domain_id;
150	guard(mutex)(&tpmi_lock);
151	mask = &tpmi_power_domain_mask[index];
152
153	return mask;
154}
155EXPORT_SYMBOL_NS_GPL(tpmi_get_power_domain_mask, "INTEL_TPMI_POWER_DOMAIN");
156
157int tpmi_get_linux_die_id(int pkg_id, int domain_id)
158{
159	if (pkg_id >= topology_max_packages() || domain_id >= MAX_POWER_DOMAINS)
160		return -EINVAL;
161
162	return domain_die_map[pkg_id * MAX_POWER_DOMAINS + domain_id];
163}
164EXPORT_SYMBOL_NS_GPL(tpmi_get_linux_die_id, "INTEL_TPMI_POWER_DOMAIN");
165
166static int tpmi_get_logical_id(unsigned int cpu, struct tpmi_cpu_info *info)
167{
168	u64 data;
169	int ret;
170
171	ret = rdmsrq_safe(MSR_PM_LOGICAL_ID, &data);
172	if (ret)
173		return ret;
174
175	info->punit_domain_id = FIELD_GET(PM_DOMAIN_ID_MASK, data);
176	if (info->punit_domain_id >= MAX_POWER_DOMAINS)
177		return -EINVAL;
178
179	info->punit_thread_id = FIELD_GET(LP_ID_MASK, data);
180	info->punit_core_id = FIELD_GET(MODULE_ID_MASK, data);
181	info->pkg_id = topology_logical_package_id(cpu);
182	info->linux_cpu = cpu;
183
184	return 0;
185}
186
187static int tpmi_cpu_online(unsigned int cpu)
188{
189	struct tpmi_cpu_info *info = &per_cpu(tpmi_cpu_info, cpu);
190	int ret, index;
191
192	/* Don't fail CPU online for some bad mapping of CPUs */
193	ret = tpmi_get_logical_id(cpu, info);
194	if (ret)
195		return 0;
196
197	index = info->pkg_id * MAX_POWER_DOMAINS + info->punit_domain_id;
198
199	guard(mutex)(&tpmi_lock);
200	cpumask_set_cpu(cpu, &tpmi_power_domain_mask[index]);
201	hash_add(tpmi_cpu_hash, &info->hnode, info->punit_core_id);
202
203	domain_die_map[info->pkg_id * MAX_POWER_DOMAINS + info->punit_domain_id] =
204			topology_die_id(cpu);
205
206	return 0;
207}
208
209static int __init tpmi_init(void)
210{
211	const struct x86_cpu_id *id;
212	u64 data;
213	int ret;
214
215	id = x86_match_cpu(tpmi_cpu_ids);
216	if (!id)
217		return -ENODEV;
218
219	/* Check for MSR 0x54 presence */
220	ret = rdmsrq_safe(MSR_PM_LOGICAL_ID, &data);
221	if (ret)
222		return ret;
223
224	tpmi_power_domain_mask = kcalloc(size_mul(topology_max_packages(), MAX_POWER_DOMAINS),
225					 sizeof(*tpmi_power_domain_mask), GFP_KERNEL);
226	if (!tpmi_power_domain_mask)
227		return -ENOMEM;
228
229	domain_die_map = kcalloc(size_mul(topology_max_packages(), MAX_POWER_DOMAINS),
230				 sizeof(*domain_die_map), GFP_KERNEL);
231	if (!domain_die_map) {
232		ret = -ENOMEM;
233		goto free_domain_mask;
234	}
235
236	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
237				"platform/x86/tpmi_power_domains:online",
238				tpmi_cpu_online, NULL);
239	if (ret < 0)
240		goto free_domain_map;
241
242	tpmi_hp_state = ret;
243
244	return 0;
245
246free_domain_map:
247	kfree(domain_die_map);
248
249free_domain_mask:
250	kfree(tpmi_power_domain_mask);
251
252	return ret;
253}
254module_init(tpmi_init)
255
256static void __exit tpmi_exit(void)
257{
258	cpuhp_remove_state(tpmi_hp_state);
259	kfree(tpmi_power_domain_mask);
260	kfree(domain_die_map);
261}
262module_exit(tpmi_exit)
263
264MODULE_DESCRIPTION("TPMI Power Domains Mapping");
265MODULE_LICENSE("GPL");