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		switch (record_header->type) {
198		case RECORD_S3_RESUME:
199			if (subtable_type != SUBTABLE_S3PT) {
200				pr_err(FW_BUG "Invalid record %d for subtable %s\n",
201				     record_header->type, signature);
202				return -EINVAL;
203			}
204			if (record_resume) {
205				pr_err("Duplicate resume performance record found.\n");
206				continue;
207			}
208			record_resume = (struct resume_performance_record *)record_header;
209			result = sysfs_create_group(fpdt_kobj, &resume_attr_group);
210			if (result)
211				return result;
212			break;
213		case RECORD_S3_SUSPEND:
214			if (subtable_type != SUBTABLE_S3PT) {
215				pr_err(FW_BUG "Invalid %d for subtable %s\n",
216				     record_header->type, signature);
217				continue;
218			}
219			if (record_suspend) {
220				pr_err("Duplicate suspend performance record found.\n");
221				continue;
222			}
223			record_suspend = (struct suspend_performance_record *)record_header;
224			result = sysfs_create_group(fpdt_kobj, &suspend_attr_group);
225			if (result)
226				return result;
227			break;
228		case RECORD_BOOT:
229			if (subtable_type != SUBTABLE_FBPT) {
230				pr_err(FW_BUG "Invalid %d for subtable %s\n",
231				     record_header->type, signature);
232				return -EINVAL;
233			}
234			if (record_boot) {
235				pr_err("Duplicate boot performance record found.\n");
236				continue;
237			}
238			record_boot = (struct boot_performance_record *)record_header;
239			result = sysfs_create_group(fpdt_kobj, &boot_attr_group);
240			if (result)
241				return result;
242			break;
243
244		default:
245			/* Other types are reserved in ACPI 6.4 spec. */
246			break;
247		}
248	}
249	return 0;
250}
251
252static int __init acpi_init_fpdt(void)
253{
254	acpi_status status;
255	struct acpi_table_header *header;
256	struct fpdt_subtable_entry *subtable;
257	u32 offset = sizeof(*header);
258
259	status = acpi_get_table(ACPI_SIG_FPDT, 0, &header);
260
261	if (ACPI_FAILURE(status))
262		return 0;
263
264	fpdt_kobj = kobject_create_and_add("fpdt", acpi_kobj);
265	if (!fpdt_kobj) {
266		acpi_put_table(header);
267		return -ENOMEM;
268	}
269
270	while (offset < header->length) {
271		subtable = (void *)header + offset;
272		switch (subtable->type) {
273		case SUBTABLE_FBPT:
274		case SUBTABLE_S3PT:
275			fpdt_process_subtable(subtable->address,
276					      subtable->type);
277			break;
278		default:
279			/* Other types are reserved in ACPI 6.4 spec. */
280			break;
281		}
282		offset += sizeof(*subtable);
283	}
284	return 0;
285}
286
287fs_initcall(acpi_init_fpdt);