1// SPDX-License-Identifier: GPL-2.0-only
2
3/*
4 * FPDT support for exporting boot and suspend/resume performance data
5 *
6 * Copyright (C) 2021 Intel Corporation. All rights reserved.
7 */
8
9#define pr_fmt(fmt) "ACPI FPDT: " fmt
10
11#include <linux/acpi.h>
12
13/*
14 * FPDT contains ACPI table header and a number of fpdt_subtable_entries.
15 * Each fpdt_subtable_entry points to a subtable: FBPT or S3PT.
16 * Each FPDT subtable (FBPT/S3PT) is composed of a fpdt_subtable_header
17 * and a number of fpdt performance records.
18 * Each FPDT performance record is composed of a fpdt_record_header and
19 * performance data fields, for boot or suspend or resume phase.
20 */
21enum fpdt_subtable_type {
22 SUBTABLE_FBPT,
23 SUBTABLE_S3PT,
24};
25
26struct fpdt_subtable_entry {
27 u16 type; /* refer to enum fpdt_subtable_type */
28 u8 length;
29 u8 revision;
30 u32 reserved;
31 u64 address; /* physical address of the S3PT/FBPT table */
32};
33
34struct fpdt_subtable_header {
35 u32 signature;
36 u32 length;
37};
38
39enum fpdt_record_type {
40 RECORD_S3_RESUME,
41 RECORD_S3_SUSPEND,
42 RECORD_BOOT,
43};
44
45struct fpdt_record_header {
46 u16 type; /* refer to enum fpdt_record_type */
47 u8 length;
48 u8 revision;
49};
50
51struct resume_performance_record {
52 struct fpdt_record_header header;
53 u32 resume_count;
54 u64 resume_prev;
55 u64 resume_avg;
56} __attribute__((packed));
57
58struct boot_performance_record {
59 struct fpdt_record_header header;
60 u32 reserved;
61 u64 firmware_start;
62 u64 bootloader_load;
63 u64 bootloader_launch;
64 u64 exitbootservice_start;
65 u64 exitbootservice_end;
66} __attribute__((packed));
67
68struct suspend_performance_record {
69 struct fpdt_record_header header;
70 u64 suspend_start;
71 u64 suspend_end;
72} __attribute__((packed));
73
74
75static struct resume_performance_record *record_resume;
76static struct suspend_performance_record *record_suspend;
77static struct boot_performance_record *record_boot;
78
79#define FPDT_ATTR(phase, name) \
80static ssize_t name##_show(struct kobject *kobj, \
81 struct kobj_attribute *attr, char *buf) \
82{ \
83 return sprintf(buf, "%llu\n", record_##phase->name); \
84} \
85static struct kobj_attribute name##_attr = \
86__ATTR(name##_ns, 0444, name##_show, NULL)
87
88FPDT_ATTR(resume, resume_prev);
89FPDT_ATTR(resume, resume_avg);
90FPDT_ATTR(suspend, suspend_start);
91FPDT_ATTR(suspend, suspend_end);
92FPDT_ATTR(boot, firmware_start);
93FPDT_ATTR(boot, bootloader_load);
94FPDT_ATTR(boot, bootloader_launch);
95FPDT_ATTR(boot, exitbootservice_start);
96FPDT_ATTR(boot, exitbootservice_end);
97
98static ssize_t resume_count_show(struct kobject *kobj,
99 struct kobj_attribute *attr, char *buf)
100{
101 return sprintf(buf, fmt: "%u\n", record_resume->resume_count);
102}
103
104static struct kobj_attribute resume_count_attr =
105__ATTR_RO(resume_count);
106
107static struct attribute *resume_attrs[] = {
108 &resume_count_attr.attr,
109 &resume_prev_attr.attr,
110 &resume_avg_attr.attr,
111 NULL
112};
113
114static const struct attribute_group resume_attr_group = {
115 .attrs = resume_attrs,
116 .name = "resume",
117};
118
119static struct attribute *suspend_attrs[] = {
120 &suspend_start_attr.attr,
121 &suspend_end_attr.attr,
122 NULL
123};
124
125static const struct attribute_group suspend_attr_group = {
126 .attrs = suspend_attrs,
127 .name = "suspend",
128};
129
130static struct attribute *boot_attrs[] = {
131 &firmware_start_attr.attr,
132 &bootloader_load_attr.attr,
133 &bootloader_launch_attr.attr,
134 &exitbootservice_start_attr.attr,
135 &exitbootservice_end_attr.attr,
136 NULL
137};
138
139static const struct attribute_group boot_attr_group = {
140 .attrs = boot_attrs,
141 .name = "boot",
142};
143
144static struct kobject *fpdt_kobj;
145
146#if defined CONFIG_X86 && defined CONFIG_PHYS_ADDR_T_64BIT
147#include <linux/processor.h>
148static bool fpdt_address_valid(u64 address)
149{
150 /*
151 * On some systems the table contains invalid addresses
152 * with unsuppored high address bits set, check for this.
153 */
154 return !(address >> boot_cpu_data.x86_phys_bits);
155}
156#else
157static bool fpdt_address_valid(u64 address)
158{
159 return true;
160}
161#endif
162
163static int fpdt_process_subtable(u64 address, u32 subtable_type)
164{
165 struct fpdt_subtable_header *subtable_header;
166 struct fpdt_record_header *record_header;
167 char *signature = (subtable_type == SUBTABLE_FBPT ? "FBPT" : "S3PT");
168 u32 length, offset;
169 int result;
170
171 if (!fpdt_address_valid(address)) {
172 pr_info(FW_BUG "invalid physical address: 0x%llx!\n", address);
173 return -EINVAL;
174 }
175
176 subtable_header = acpi_os_map_memory(where: address, length: sizeof(*subtable_header));
177 if (!subtable_header)
178 return -ENOMEM;
179
180 if (strncmp((char *)&subtable_header->signature, signature, 4)) {
181 pr_info(FW_BUG "subtable signature and type mismatch!\n");
182 return -EINVAL;
183 }
184
185 length = subtable_header->length;
186 acpi_os_unmap_memory(logical_address: subtable_header, size: sizeof(*subtable_header));
187
188 subtable_header = acpi_os_map_memory(where: address, length);
189 if (!subtable_header)
190 return -ENOMEM;
191
192 offset = sizeof(*subtable_header);
193 while (offset < length) {
194 record_header = (void *)subtable_header + offset;
195 offset += record_header->length;
196
197 if (!record_header->length) {
198 pr_err(FW_BUG "Zero-length record found in FPTD.\n");
199 result = -EINVAL;
200 goto err;
201 }
202
203 switch (record_header->type) {
204 case RECORD_S3_RESUME:
205 if (subtable_type != SUBTABLE_S3PT) {
206 pr_err(FW_BUG "Invalid record %d for subtable %s\n",
207 record_header->type, signature);
208 result = -EINVAL;
209 goto err;
210 }
211 if (record_resume) {
212 pr_err("Duplicate resume performance record found.\n");
213 continue;
214 }
215 record_resume = (struct resume_performance_record *)record_header;
216 result = sysfs_create_group(kobj: fpdt_kobj, grp: &resume_attr_group);
217 if (result)
218 goto err;
219 break;
220 case RECORD_S3_SUSPEND:
221 if (subtable_type != SUBTABLE_S3PT) {
222 pr_err(FW_BUG "Invalid %d for subtable %s\n",
223 record_header->type, signature);
224 continue;
225 }
226 if (record_suspend) {
227 pr_err("Duplicate suspend performance record found.\n");
228 continue;
229 }
230 record_suspend = (struct suspend_performance_record *)record_header;
231 result = sysfs_create_group(kobj: fpdt_kobj, grp: &suspend_attr_group);
232 if (result)
233 goto err;
234 break;
235 case RECORD_BOOT:
236 if (subtable_type != SUBTABLE_FBPT) {
237 pr_err(FW_BUG "Invalid %d for subtable %s\n",
238 record_header->type, signature);
239 result = -EINVAL;
240 goto err;
241 }
242 if (record_boot) {
243 pr_err("Duplicate boot performance record found.\n");
244 continue;
245 }
246 record_boot = (struct boot_performance_record *)record_header;
247 result = sysfs_create_group(kobj: fpdt_kobj, grp: &boot_attr_group);
248 if (result)
249 goto err;
250 break;
251
252 default:
253 /* Other types are reserved in ACPI 6.4 spec. */
254 break;
255 }
256 }
257 return 0;
258
259err:
260 if (record_boot)
261 sysfs_remove_group(kobj: fpdt_kobj, grp: &boot_attr_group);
262
263 if (record_suspend)
264 sysfs_remove_group(kobj: fpdt_kobj, grp: &suspend_attr_group);
265
266 if (record_resume)
267 sysfs_remove_group(kobj: fpdt_kobj, grp: &resume_attr_group);
268
269 return result;
270}
271
272static int __init acpi_init_fpdt(void)
273{
274 acpi_status status;
275 struct acpi_table_header *header;
276 struct fpdt_subtable_entry *subtable;
277 u32 offset = sizeof(*header);
278 int result;
279
280 status = acpi_get_table(ACPI_SIG_FPDT, instance: 0, out_table: &header);
281
282 if (ACPI_FAILURE(status))
283 return 0;
284
285 fpdt_kobj = kobject_create_and_add(name: "fpdt", parent: acpi_kobj);
286 if (!fpdt_kobj) {
287 result = -ENOMEM;
288 goto err_nomem;
289 }
290
291 while (offset < header->length) {
292 subtable = (void *)header + offset;
293 switch (subtable->type) {
294 case SUBTABLE_FBPT:
295 case SUBTABLE_S3PT:
296 result = fpdt_process_subtable(address: subtable->address,
297 subtable_type: subtable->type);
298 if (result)
299 goto err_subtable;
300 break;
301 default:
302 /* Other types are reserved in ACPI 6.4 spec. */
303 break;
304 }
305 offset += sizeof(*subtable);
306 }
307 return 0;
308err_subtable:
309 kobject_put(kobj: fpdt_kobj);
310
311err_nomem:
312 acpi_put_table(table: header);
313 return result;
314}
315
316fs_initcall(acpi_init_fpdt);
317

source code of linux/drivers/acpi/acpi_fpdt.c