drivers/acpi/pfr_telemetry.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * ACPI Platform Firmware Runtime Telemetry driver
   4  *
   5  * Copyright (C) 2021 Intel Corporation
   6  * Author: Chen Yu <yu.c.chen@intel.com>
   7  *
   8  * This driver allows user space to fetch telemetry data from the
   9  * firmware with the help of the Platform Firmware Runtime Telemetry
  10  * interface.
  11  */
  12 #include <linux/acpi.h>
  13 #include <linux/device.h>
  14 #include <linux/err.h>
  15 #include <linux/errno.h>
  16 #include <linux/file.h>
  17 #include <linux/fs.h>
  18 #include <linux/miscdevice.h>
  19 #include <linux/module.h>
  20 #include <linux/mm.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/string.h>
  23 #include <linux/uaccess.h>
  24 #include <linux/uio.h>
  25 #include <linux/uuid.h>
  26
  27 #include <uapi/linux/pfrut.h>
  28
  29 #define PFRT_LOG_EXEC_IDX       0
  30 #define PFRT_LOG_HISTORY_IDX    1
  31
  32 #define PFRT_LOG_ERR            0
  33 #define PFRT_LOG_WARN   1
  34 #define PFRT_LOG_INFO   2
  35 #define PFRT_LOG_VERB   4
  36
  37 #define PFRT_FUNC_SET_LEV               1
  38 #define PFRT_FUNC_GET_LEV               2
  39 #define PFRT_FUNC_GET_DATA              3
  40
  41 #define PFRT_REVID_1            1
  42 #define PFRT_REVID_2            2
  43 #define PFRT_DEFAULT_REV_ID     PFRT_REVID_1
  44
  45 enum log_index {
  46         LOG_STATUS_IDX = 0,
  47         LOG_EXT_STATUS_IDX = 1,
  48         LOG_MAX_SZ_IDX = 2,
  49         LOG_CHUNK1_LO_IDX = 3,
  50         LOG_CHUNK1_HI_IDX = 4,
  51         LOG_CHUNK1_SZ_IDX = 5,
  52         LOG_CHUNK2_LO_IDX = 6,
  53         LOG_CHUNK2_HI_IDX = 7,
  54         LOG_CHUNK2_SZ_IDX = 8,
  55         LOG_ROLLOVER_CNT_IDX = 9,
  56         LOG_RESET_CNT_IDX = 10,
  57         LOG_NR_IDX
  58 };
  59
  60 struct pfrt_log_device {
  61         int index;
  62         struct pfrt_log_info info;
  63         struct device *parent_dev;
  64         struct miscdevice miscdev;
  65 };
  66
  67 /* pfrt_guid is the parameter for _DSM method */
  68 static const guid_t pfrt_log_guid =
  69         GUID_INIT(0x75191659, 0x8178, 0x4D9D, 0xB8, 0x8F, 0xAC, 0x5E,
  70                   0x5E, 0x93, 0xE8, 0xBF);
  71
  72 static DEFINE_IDA(pfrt_log_ida);
  73
  74 static inline struct pfrt_log_device *to_pfrt_log_dev(struct file *file)
  75 {
  76         return container_of(file->private_data, struct pfrt_log_device, miscdev);
  77 }
  78
  79 static int get_pfrt_log_data_info(struct pfrt_log_data_info *data_info,
  80                                   struct pfrt_log_device *pfrt_log_dev)
  81 {
  82         acpi_handle handle = ACPI_HANDLE(pfrt_log_dev->parent_dev);
  83         union acpi_object *out_obj, in_obj, in_buf;
  84         int ret = -EBUSY;
  85
  86         memset(data_info, 0, sizeof(*data_info));
  87         memset(&in_obj, 0, sizeof(in_obj));
  88         memset(&in_buf, 0, sizeof(in_buf));
  89         in_obj.type = ACPI_TYPE_PACKAGE;
  90         in_obj.package.count = 1;
  91         in_obj.package.elements = &in_buf;
  92         in_buf.type = ACPI_TYPE_INTEGER;
  93         in_buf.integer.value = pfrt_log_dev->info.log_type;
  94
  95         out_obj = acpi_evaluate_dsm_typed(handle, &pfrt_log_guid,
  96                                           pfrt_log_dev->info.log_revid, PFRT_FUNC_GET_DATA,
  97                                           &in_obj, ACPI_TYPE_PACKAGE);
  98         if (!out_obj)
  99                 return -EINVAL;
 100
 101         if (out_obj->package.count < LOG_NR_IDX ||
 102             out_obj->package.elements[LOG_STATUS_IDX].type != ACPI_TYPE_INTEGER ||
 103             out_obj->package.elements[LOG_EXT_STATUS_IDX].type != ACPI_TYPE_INTEGER ||
 104             out_obj->package.elements[LOG_MAX_SZ_IDX].type != ACPI_TYPE_INTEGER ||
 105             out_obj->package.elements[LOG_CHUNK1_LO_IDX].type != ACPI_TYPE_INTEGER ||
 106             out_obj->package.elements[LOG_CHUNK1_HI_IDX].type != ACPI_TYPE_INTEGER ||
 107             out_obj->package.elements[LOG_CHUNK1_SZ_IDX].type != ACPI_TYPE_INTEGER ||
 108             out_obj->package.elements[LOG_CHUNK2_LO_IDX].type != ACPI_TYPE_INTEGER ||
 109             out_obj->package.elements[LOG_CHUNK2_HI_IDX].type != ACPI_TYPE_INTEGER ||
 110             out_obj->package.elements[LOG_CHUNK2_SZ_IDX].type != ACPI_TYPE_INTEGER ||
 111             out_obj->package.elements[LOG_ROLLOVER_CNT_IDX].type != ACPI_TYPE_INTEGER ||
 112             out_obj->package.elements[LOG_RESET_CNT_IDX].type != ACPI_TYPE_INTEGER)
 113                 goto free_acpi_buffer;
 114
 115         data_info->status = out_obj->package.elements[LOG_STATUS_IDX].integer.value;
 116         data_info->ext_status =
 117                 out_obj->package.elements[LOG_EXT_STATUS_IDX].integer.value;
 118         if (data_info->status != DSM_SUCCEED) {
 119                 dev_dbg(pfrt_log_dev->parent_dev, "Error Status:%d\n", data_info->status);
 120                 dev_dbg(pfrt_log_dev->parent_dev, "Error Extend Status:%d\n",
 121                         data_info->ext_status);
 122                 goto free_acpi_buffer;
 123         }
 124
 125         data_info->max_data_size =
 126                 out_obj->package.elements[LOG_MAX_SZ_IDX].integer.value;
 127         data_info->chunk1_addr_lo =
 128                 out_obj->package.elements[LOG_CHUNK1_LO_IDX].integer.value;
 129         data_info->chunk1_addr_hi =
 130                 out_obj->package.elements[LOG_CHUNK1_HI_IDX].integer.value;
 131         data_info->chunk1_size =
 132                 out_obj->package.elements[LOG_CHUNK1_SZ_IDX].integer.value;
 133         data_info->chunk2_addr_lo =
 134                 out_obj->package.elements[LOG_CHUNK2_LO_IDX].integer.value;
 135         data_info->chunk2_addr_hi =
 136                 out_obj->package.elements[LOG_CHUNK2_HI_IDX].integer.value;
 137         data_info->chunk2_size =
 138                 out_obj->package.elements[LOG_CHUNK2_SZ_IDX].integer.value;
 139         data_info->rollover_cnt =
 140                 out_obj->package.elements[LOG_ROLLOVER_CNT_IDX].integer.value;
 141         data_info->reset_cnt =
 142                 out_obj->package.elements[LOG_RESET_CNT_IDX].integer.value;
 143
 144         ret = 0;
 145
 146 free_acpi_buffer:
 147         ACPI_FREE(out_obj);
 148
 149         return ret;
 150 }
 151
 152 static int set_pfrt_log_level(int level, struct pfrt_log_device *pfrt_log_dev)
 153 {
 154         acpi_handle handle = ACPI_HANDLE(pfrt_log_dev->parent_dev);
 155         union acpi_object *out_obj, *obj, in_obj, in_buf;
 156         enum pfru_dsm_status status, ext_status;
 157         int ret = 0;
 158
 159         memset(&in_obj, 0, sizeof(in_obj));
 160         memset(&in_buf, 0, sizeof(in_buf));
 161         in_obj.type = ACPI_TYPE_PACKAGE;
 162         in_obj.package.count = 1;
 163         in_obj.package.elements = &in_buf;
 164         in_buf.type = ACPI_TYPE_INTEGER;
 165         in_buf.integer.value = level;
 166
 167         out_obj = acpi_evaluate_dsm_typed(handle, &pfrt_log_guid,
 168                                           pfrt_log_dev->info.log_revid, PFRT_FUNC_SET_LEV,
 169                                           &in_obj, ACPI_TYPE_PACKAGE);
 170         if (!out_obj)
 171                 return -EINVAL;
 172
 173         obj = &out_obj->package.elements[0];
 174         status = obj->integer.value;
 175         if (status != DSM_SUCCEED) {
 176                 obj = &out_obj->package.elements[1];
 177                 ext_status = obj->integer.value;
 178                 dev_dbg(pfrt_log_dev->parent_dev, "Error Status:%d\n", status);
 179                 dev_dbg(pfrt_log_dev->parent_dev, "Error Extend Status:%d\n", ext_status);
 180                 ret = -EBUSY;
 181         }
 182
 183         ACPI_FREE(out_obj);
 184
 185         return ret;
 186 }
 187
 188 static int get_pfrt_log_level(struct pfrt_log_device *pfrt_log_dev)
 189 {
 190         acpi_handle handle = ACPI_HANDLE(pfrt_log_dev->parent_dev);
 191         union acpi_object *out_obj, *obj;
 192         enum pfru_dsm_status status, ext_status;
 193         int ret = -EBUSY;
 194
 195         out_obj = acpi_evaluate_dsm_typed(handle, &pfrt_log_guid,
 196                                           pfrt_log_dev->info.log_revid, PFRT_FUNC_GET_LEV,
 197                                           NULL, ACPI_TYPE_PACKAGE);
 198         if (!out_obj)
 199                 return -EINVAL;
 200
 201         obj = &out_obj->package.elements[0];
 202         if (obj->type != ACPI_TYPE_INTEGER)
 203                 goto free_acpi_buffer;
 204
 205         status = obj->integer.value;
 206         if (status != DSM_SUCCEED) {
 207                 obj = &out_obj->package.elements[1];
 208                 ext_status = obj->integer.value;
 209                 dev_dbg(pfrt_log_dev->parent_dev, "Error Status:%d\n", status);
 210                 dev_dbg(pfrt_log_dev->parent_dev, "Error Extend Status:%d\n", ext_status);
 211                 goto free_acpi_buffer;
 212         }
 213
 214         obj = &out_obj->package.elements[2];
 215         if (obj->type != ACPI_TYPE_INTEGER)
 216                 goto free_acpi_buffer;
 217
 218         ret = obj->integer.value;
 219
 220 free_acpi_buffer:
 221         ACPI_FREE(out_obj);
 222
 223         return ret;
 224 }
 225
 226 static int valid_log_level(u32 level)
 227 {
 228         return level == PFRT_LOG_ERR || level == PFRT_LOG_WARN ||
 229                level == PFRT_LOG_INFO || level == PFRT_LOG_VERB;
 230 }
 231
 232 static int valid_log_type(u32 type)
 233 {
 234         return type == PFRT_LOG_EXEC_IDX || type == PFRT_LOG_HISTORY_IDX;
 235 }
 236
 237 static inline int valid_log_revid(u32 id)
 238 {
 239         return id == PFRT_REVID_1 || id == PFRT_REVID_2;
 240 }
 241
 242 static long pfrt_log_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 243 {
 244         struct pfrt_log_device *pfrt_log_dev = to_pfrt_log_dev(file);
 245         struct pfrt_log_data_info data_info;
 246         struct pfrt_log_info info;
 247         void __user *p;
 248         int ret = 0;
 249
 250         p = (void __user *)arg;
 251
 252         switch (cmd) {
 253         case PFRT_LOG_IOC_SET_INFO:
 254                 if (copy_from_user(&info, p, sizeof(info)))
 255                         return -EFAULT;
 256
 257                 if (valid_log_revid(info.log_revid))
 258                         pfrt_log_dev->info.log_revid = info.log_revid;
 259
 260                 if (valid_log_level(info.log_level)) {
 261                         ret = set_pfrt_log_level(info.log_level, pfrt_log_dev);
 262                         if (ret < 0)
 263                                 return ret;
 264
 265                         pfrt_log_dev->info.log_level = info.log_level;
 266                 }
 267
 268                 if (valid_log_type(info.log_type))
 269                         pfrt_log_dev->info.log_type = info.log_type;
 270
 271                 return 0;
 272
 273         case PFRT_LOG_IOC_GET_INFO:
 274                 info.log_level = get_pfrt_log_level(pfrt_log_dev);
 275                 info.log_type = pfrt_log_dev->info.log_type;
 276                 info.log_revid = pfrt_log_dev->info.log_revid;
 277                 if (copy_to_user(p, &info, sizeof(info)))
 278                         return -EFAULT;
 279
 280                 return 0;
 281
 282         case PFRT_LOG_IOC_GET_DATA_INFO:
 283                 ret = get_pfrt_log_data_info(&data_info, pfrt_log_dev);
 284                 if (ret)
 285                         return ret;
 286
 287                 if (copy_to_user(p, &data_info, sizeof(struct pfrt_log_data_info)))
 288                         return -EFAULT;
 289
 290                 return 0;
 291
 292         default:
 293                 return -ENOTTY;
 294         }
 295 }
 296
 297 static int
 298 pfrt_log_mmap(struct file *file, struct vm_area_struct *vma)
 299 {
 300         struct pfrt_log_device *pfrt_log_dev;
 301         struct pfrt_log_data_info info;
 302         unsigned long psize, vsize;
 303         phys_addr_t base_addr;
 304         int ret;
 305
 306         if (vma->vm_flags & VM_WRITE)
 307                 return -EROFS;
 308
 309         /* changing from read to write with mprotect is not allowed */
 310         vm_flags_clear(vma, VM_MAYWRITE);
 311
 312         pfrt_log_dev = to_pfrt_log_dev(file);
 313
 314         ret = get_pfrt_log_data_info(&info, pfrt_log_dev);
 315         if (ret)
 316                 return ret;
 317
 318         base_addr = (phys_addr_t)((info.chunk2_addr_hi << 32) | info.chunk2_addr_lo);
 319         /* pfrt update has not been launched yet */
 320         if (!base_addr)
 321                 return -ENODEV;
 322
 323         psize = info.max_data_size;
 324         /* base address and total buffer size must be page aligned */
 325         if (!PAGE_ALIGNED(base_addr) || !PAGE_ALIGNED(psize))
 326                 return -ENODEV;
 327
 328         vsize = vma->vm_end - vma->vm_start;
 329         if (vsize > psize)
 330                 return -EINVAL;
 331
 332         vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 333         if (io_remap_pfn_range(vma, vma->vm_start, PFN_DOWN(base_addr),
 334                                vsize, vma->vm_page_prot))
 335                 return -EAGAIN;
 336
 337         return 0;
 338 }
 339
 340 static const struct file_operations acpi_pfrt_log_fops = {
 341         .owner          = THIS_MODULE,
 342         .mmap           = pfrt_log_mmap,
 343         .unlocked_ioctl = pfrt_log_ioctl,
 344         .llseek         = noop_llseek,
 345 };
 346
 347 static void acpi_pfrt_log_remove(struct platform_device *pdev)
 348 {
 349         struct pfrt_log_device *pfrt_log_dev = platform_get_drvdata(pdev);
 350
 351         misc_deregister(&pfrt_log_dev->miscdev);
 352 }
 353
 354 static void pfrt_log_put_idx(void *data)
 355 {
 356         struct pfrt_log_device *pfrt_log_dev = data;
 357
 358         ida_free(&pfrt_log_ida, pfrt_log_dev->index);
 359 }
 360
 361 static int acpi_pfrt_log_probe(struct platform_device *pdev)
 362 {
 363         acpi_handle handle = ACPI_HANDLE(&pdev->dev);
 364         struct pfrt_log_device *pfrt_log_dev;
 365         int ret;
 366
 367         if (!acpi_has_method(handle, "_DSM")) {
 368                 dev_dbg(&pdev->dev, "Missing _DSM\n");
 369                 return -ENODEV;
 370         }
 371
 372         pfrt_log_dev = devm_kzalloc(&pdev->dev, sizeof(*pfrt_log_dev), GFP_KERNEL);
 373         if (!pfrt_log_dev)
 374                 return -ENOMEM;
 375
 376         ret = ida_alloc(&pfrt_log_ida, GFP_KERNEL);
 377         if (ret < 0)
 378                 return ret;
 379
 380         pfrt_log_dev->index = ret;
 381         ret = devm_add_action_or_reset(&pdev->dev, pfrt_log_put_idx, pfrt_log_dev);
 382         if (ret)
 383                 return ret;
 384
 385         pfrt_log_dev->info.log_revid = PFRT_DEFAULT_REV_ID;
 386         pfrt_log_dev->parent_dev = &pdev->dev;
 387
 388         pfrt_log_dev->miscdev.minor = MISC_DYNAMIC_MINOR;
 389         pfrt_log_dev->miscdev.name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
 390                                                     "pfrt%d",
 391                                                     pfrt_log_dev->index);
 392         if (!pfrt_log_dev->miscdev.name)
 393                 return -ENOMEM;
 394
 395         pfrt_log_dev->miscdev.nodename = devm_kasprintf(&pdev->dev, GFP_KERNEL,
 396                                                         "acpi_pfr_telemetry%d",
 397                                                         pfrt_log_dev->index);
 398         if (!pfrt_log_dev->miscdev.nodename)
 399                 return -ENOMEM;
 400
 401         pfrt_log_dev->miscdev.fops = &acpi_pfrt_log_fops;
 402         pfrt_log_dev->miscdev.parent = &pdev->dev;
 403
 404         ret = misc_register(&pfrt_log_dev->miscdev);
 405         if (ret)
 406                 return ret;
 407
 408         platform_set_drvdata(pdev, pfrt_log_dev);
 409
 410         return 0;
 411 }
 412
 413 static const struct acpi_device_id acpi_pfrt_log_ids[] = {
 414         {"INTC1081"},
 415         {}
 416 };
 417 MODULE_DEVICE_TABLE(acpi, acpi_pfrt_log_ids);
 418
 419 static struct platform_driver acpi_pfrt_log_driver = {
 420         .driver = {
 421                 .name = "pfr_telemetry",
 422                 .acpi_match_table = acpi_pfrt_log_ids,
 423         },
 424         .probe = acpi_pfrt_log_probe,
 425         .remove = acpi_pfrt_log_remove,
 426 };
 427 module_platform_driver(acpi_pfrt_log_driver);
 428
 429 MODULE_DESCRIPTION("Platform Firmware Runtime Update Telemetry driver");
 430 MODULE_LICENSE("GPL v2");