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, "%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(address, 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(subtable_header, sizeof(*subtable_header));
187
188	subtable_header = acpi_os_map_memory(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(fpdt_kobj, &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(fpdt_kobj, &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(fpdt_kobj, &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(fpdt_kobj, &boot_attr_group);
262
263	if (record_suspend)
264		sysfs_remove_group(fpdt_kobj, &suspend_attr_group);
265
266	if (record_resume)
267		sysfs_remove_group(fpdt_kobj, &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, 0, &header);
281
282	if (ACPI_FAILURE(status))
283		return 0;
284
285	fpdt_kobj = kobject_create_and_add("fpdt", 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(subtable->address,
297					      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(fpdt_kobj);
310
311err_nomem:
312	acpi_put_table(header);
313	return result;
314}
315
316fs_initcall(acpi_init_fpdt);
317