drivers/acpi/acpi_fpdt.c

   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  */
  21 enum fpdt_subtable_type {
  22         SUBTABLE_FBPT,
  23         SUBTABLE_S3PT,
  24 };
  25
  26 struct 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
  34 struct fpdt_subtable_header {
  35         u32 signature;
  36         u32 length;
  37 };
  38
  39 enum fpdt_record_type {
  40         RECORD_S3_RESUME,
  41         RECORD_S3_SUSPEND,
  42         RECORD_BOOT,
  43 };
  44
  45 struct fpdt_record_header {
  46         u16 type;               /* refer to enum fpdt_record_type */
  47         u8 length;
  48         u8 revision;
  49 };
  50
  51 struct 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
  58 struct 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
  68 struct suspend_performance_record {
  69         struct fpdt_record_header header;
  70         u64 suspend_start;
  71         u64 suspend_end;
  72 } __attribute__((packed));
  73
  74
  75 static struct resume_performance_record *record_resume;
  76 static struct suspend_performance_record *record_suspend;
  77 static struct boot_performance_record *record_boot;
  78
  79 #define FPDT_ATTR(phase, name)  \
  80 static 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 }       \
  85 static struct kobj_attribute name##_attr =      \
  86 __ATTR(name##_ns, 0444, name##_show, NULL)
  87
  88 FPDT_ATTR(resume, resume_prev);
  89 FPDT_ATTR(resume, resume_avg);
  90 FPDT_ATTR(suspend, suspend_start);
  91 FPDT_ATTR(suspend, suspend_end);
  92 FPDT_ATTR(boot, firmware_start);
  93 FPDT_ATTR(boot, bootloader_load);
  94 FPDT_ATTR(boot, bootloader_launch);
  95 FPDT_ATTR(boot, exitbootservice_start);
  96 FPDT_ATTR(boot, exitbootservice_end);
  97
  98 static 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
 104 static struct kobj_attribute resume_count_attr =
 105 __ATTR_RO(resume_count);
 106
 107 static struct attribute *resume_attrs[] = {
 108         &resume_count_attr.attr,
 109         &resume_prev_attr.attr,
 110         &resume_avg_attr.attr,
 111         NULL
 112 };
 113
 114 static const struct attribute_group resume_attr_group = {
 115         .attrs = resume_attrs,
 116         .name = "resume",
 117 };
 118
 119 static struct attribute *suspend_attrs[] = {
 120         &suspend_start_attr.attr,
 121         &suspend_end_attr.attr,
 122         NULL
 123 };
 124
 125 static const struct attribute_group suspend_attr_group = {
 126         .attrs = suspend_attrs,
 127         .name = "suspend",
 128 };
 129
 130 static 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
 139 static const struct attribute_group boot_attr_group = {
 140         .attrs = boot_attrs,
 141         .name = "boot",
 142 };
 143
 144 static struct kobject *fpdt_kobj;
 145
 146 #if defined CONFIG_X86 && defined CONFIG_PHYS_ADDR_T_64BIT
 147 #include <linux/processor.h>
 148 static 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
 157 static bool fpdt_address_valid(u64 address)
 158 {
 159         return true;
 160 }
 161 #endif
 162
 163 static 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
 259 err:
 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
 272 static 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;
 308 err_subtable:
 309         kobject_put(fpdt_kobj);
 310
 311 err_nomem:
 312         acpi_put_table(header);
 313         return result;
 314 }
 315
 316 fs_initcall(acpi_init_fpdt);