sysfs-driver-ufs (68814B)
1What: /sys/bus/*/drivers/ufshcd/*/auto_hibern8 2Date: March 2018 3Contact: linux-scsi@vger.kernel.org 4Description: 5 This file contains the auto-hibernate idle timer setting of a 6 UFS host controller. A value of '0' means auto-hibernate is not 7 enabled. Otherwise the value is the number of microseconds of 8 idle time before the UFS host controller will autonomously put 9 the link into hibernate state. That will save power at the 10 expense of increased latency. Note that the hardware supports 11 10-bit values with a power-of-ten multiplier which allows a 12 maximum value of 102300000. Refer to the UFS Host Controller 13 Interface specification for more details. 14 15What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/device_type 16What: /sys/bus/platform/devices/*.ufs/device_descriptor/device_type 17Date: February 2018 18Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 19Description: This file shows the device type. This is one of the UFS 20 device descriptor parameters. The full information about 21 the descriptor could be found at UFS specifications 2.1. 22 23 The file is read only. 24 25What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/device_class 26What: /sys/bus/platform/devices/*.ufs/device_descriptor/device_class 27Date: February 2018 28Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 29Description: This file shows the device class. This is one of the UFS 30 device descriptor parameters. The full information about 31 the descriptor could be found at UFS specifications 2.1. 32 33 The file is read only. 34 35What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/device_sub_class 36What: /sys/bus/platform/devices/*.ufs/device_descriptor/device_sub_class 37Date: February 2018 38Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 39Description: This file shows the UFS storage subclass. This is one of 40 the UFS device descriptor parameters. The full information 41 about the descriptor could be found at UFS specifications 2.1. 42 43 The file is read only. 44 45What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/protocol 46What: /sys/bus/platform/devices/*.ufs/device_descriptor/protocol 47Date: February 2018 48Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 49Description: This file shows the protocol supported by an UFS device. 50 This is one of the UFS device descriptor parameters. 51 The full information about the descriptor could be found 52 at UFS specifications 2.1. 53 54 The file is read only. 55 56What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/number_of_luns 57What: /sys/bus/platform/devices/*.ufs/device_descriptor/number_of_luns 58Date: February 2018 59Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 60Description: This file shows number of logical units. This is one of 61 the UFS device descriptor parameters. The full information 62 about the descriptor could be found at UFS specifications 2.1. 63 64 The file is read only. 65 66What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/number_of_wluns 67What: /sys/bus/platform/devices/*.ufs/device_descriptor/number_of_wluns 68Date: February 2018 69Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 70Description: This file shows number of well known logical units. 71 This is one of the UFS device descriptor parameters. 72 The full information about the descriptor could be found 73 at UFS specifications 2.1. 74 75 The file is read only. 76 77What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/boot_enable 78What: /sys/bus/platform/devices/*.ufs/device_descriptor/boot_enable 79Date: February 2018 80Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 81Description: This file shows value that indicates whether the device is 82 enabled for boot. This is one of the UFS device descriptor 83 parameters. The full information about the descriptor could 84 be found at UFS specifications 2.1. 85 86 The file is read only. 87 88What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/descriptor_access_enable 89What: /sys/bus/platform/devices/*.ufs/device_descriptor/descriptor_access_enable 90Date: February 2018 91Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 92Description: This file shows value that indicates whether the device 93 descriptor could be read after partial initialization phase 94 of the boot sequence. This is one of the UFS device descriptor 95 parameters. The full information about the descriptor could 96 be found at UFS specifications 2.1. 97 98 The file is read only. 99 100What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/initial_power_mode 101What: /sys/bus/platform/devices/*.ufs/device_descriptor/initial_power_mode 102Date: February 2018 103Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 104Description: This file shows value that defines the power mode after 105 device initialization or hardware reset. This is one of 106 the UFS device descriptor parameters. The full information 107 about the descriptor could be found at UFS specifications 2.1. 108 109 The file is read only. 110 111What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/high_priority_lun 112What: /sys/bus/platform/devices/*.ufs/device_descriptor/high_priority_lun 113Date: February 2018 114Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 115Description: This file shows the high priority lun. This is one of 116 the UFS device descriptor parameters. The full information 117 about the descriptor could be found at UFS specifications 2.1. 118 119 The file is read only. 120 121What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/secure_removal_type 122What: /sys/bus/platform/devices/*.ufs/device_descriptor/secure_removal_type 123Date: February 2018 124Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 125Description: This file shows the secure removal type. This is one of 126 the UFS device descriptor parameters. The full information 127 about the descriptor could be found at UFS specifications 2.1. 128 129 The file is read only. 130 131What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/support_security_lun 132What: /sys/bus/platform/devices/*.ufs/device_descriptor/support_security_lun 133Date: February 2018 134Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 135Description: This file shows whether the security lun is supported. 136 This is one of the UFS device descriptor parameters. 137 The full information about the descriptor could be found 138 at UFS specifications 2.1. 139 140 The file is read only. 141 142What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/bkops_termination_latency 143What: /sys/bus/platform/devices/*.ufs/device_descriptor/bkops_termination_latency 144Date: February 2018 145Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 146Description: This file shows the background operations termination 147 latency. This is one of the UFS device descriptor parameters. 148 The full information about the descriptor could be found 149 at UFS specifications 2.1. 150 151 The file is read only. 152 153What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/initial_active_icc_level 154What: /sys/bus/platform/devices/*.ufs/device_descriptor/initial_active_icc_level 155Date: February 2018 156Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 157Description: This file shows the initial active ICC level. This is one 158 of the UFS device descriptor parameters. The full information 159 about the descriptor could be found at UFS specifications 2.1. 160 161 The file is read only. 162 163What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/specification_version 164What: /sys/bus/platform/devices/*.ufs/device_descriptor/specification_version 165Date: February 2018 166Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 167Description: This file shows the specification version. This is one 168 of the UFS device descriptor parameters. The full information 169 about the descriptor could be found at UFS specifications 2.1. 170 171 The file is read only. 172 173What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/manufacturing_date 174What: /sys/bus/platform/devices/*.ufs/device_descriptor/manufacturing_date 175Date: February 2018 176Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 177Description: This file shows the manufacturing date in BCD format. 178 This is one of the UFS device descriptor parameters. 179 The full information about the descriptor could be found 180 at UFS specifications 2.1. 181 182 The file is read only. 183 184What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/manufacturer_id 185What: /sys/bus/platform/devices/*.ufs/device_descriptor/manufacturer_id 186Date: February 2018 187Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 188Description: This file shows the manufacturer ID. This is one of the 189 UFS device descriptor parameters. The full information about 190 the descriptor could be found at UFS specifications 2.1. 191 192 The file is read only. 193 194What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/rtt_capability 195What: /sys/bus/platform/devices/*.ufs/device_descriptor/rtt_capability 196Date: February 2018 197Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 198Description: This file shows the maximum number of outstanding RTTs 199 supported by the device. This is one of the UFS device 200 descriptor parameters. The full information about 201 the descriptor could be found at UFS specifications 2.1. 202 203 The file is read only. 204 205What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/rtc_update 206What: /sys/bus/platform/devices/*.ufs/device_descriptor/rtc_update 207Date: February 2018 208Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 209Description: This file shows the frequency and method of the realtime 210 clock update. This is one of the UFS device descriptor 211 parameters. The full information about the descriptor 212 could be found at UFS specifications 2.1. 213 214 The file is read only. 215 216What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/ufs_features 217What: /sys/bus/platform/devices/*.ufs/device_descriptor/ufs_features 218Date: February 2018 219Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 220Description: This file shows which features are supported by the device. 221 This is one of the UFS device descriptor parameters. 222 The full information about the descriptor could be 223 found at UFS specifications 2.1. 224 225 The file is read only. 226 227What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/ffu_timeout 228What: /sys/bus/platform/devices/*.ufs/device_descriptor/ffu_timeout 229Date: February 2018 230Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 231Description: This file shows the FFU timeout. This is one of the 232 UFS device descriptor parameters. The full information 233 about the descriptor could be found at UFS specifications 2.1. 234 235 The file is read only. 236 237What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/queue_depth 238What: /sys/bus/platform/devices/*.ufs/device_descriptor/queue_depth 239Date: February 2018 240Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 241Description: This file shows the device queue depth. This is one of the 242 UFS device descriptor parameters. The full information 243 about the descriptor could be found at UFS specifications 2.1. 244 245 The file is read only. 246 247What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/device_version 248What: /sys/bus/platform/devices/*.ufs/device_descriptor/device_version 249Date: February 2018 250Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 251Description: This file shows the device version. This is one of the 252 UFS device descriptor parameters. The full information 253 about the descriptor could be found at UFS specifications 2.1. 254 255 The file is read only. 256 257What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/number_of_secure_wpa 258What: /sys/bus/platform/devices/*.ufs/device_descriptor/number_of_secure_wpa 259Date: February 2018 260Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 261Description: This file shows number of secure write protect areas 262 supported by the device. This is one of the UFS device 263 descriptor parameters. The full information about 264 the descriptor could be found at UFS specifications 2.1. 265 266 The file is read only. 267 268What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/psa_max_data_size 269What: /sys/bus/platform/devices/*.ufs/device_descriptor/psa_max_data_size 270Date: February 2018 271Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 272Description: This file shows the maximum amount of data that may be 273 written during the pre-soldering phase of the PSA flow. 274 This is one of the UFS device descriptor parameters. 275 The full information about the descriptor could be found 276 at UFS specifications 2.1. 277 278 The file is read only. 279 280What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/psa_state_timeout 281What: /sys/bus/platform/devices/*.ufs/device_descriptor/psa_state_timeout 282Date: February 2018 283Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 284Description: This file shows the command maximum timeout for a change 285 in PSA state. This is one of the UFS device descriptor 286 parameters. The full information about the descriptor could 287 be found at UFS specifications 2.1. 288 289 The file is read only. 290 291 292What: /sys/bus/platform/drivers/ufshcd/*/interconnect_descriptor/unipro_version 293What: /sys/bus/platform/devices/*.ufs/interconnect_descriptor/unipro_version 294Date: February 2018 295Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 296Description: This file shows the MIPI UniPro version number in BCD format. 297 This is one of the UFS interconnect descriptor parameters. 298 The full information about the descriptor could be found at 299 UFS specifications 2.1. 300 301 The file is read only. 302 303What: /sys/bus/platform/drivers/ufshcd/*/interconnect_descriptor/mphy_version 304What: /sys/bus/platform/devices/*.ufs/interconnect_descriptor/mphy_version 305Date: February 2018 306Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 307Description: This file shows the MIPI M-PHY version number in BCD format. 308 This is one of the UFS interconnect descriptor parameters. 309 The full information about the descriptor could be found at 310 UFS specifications 2.1. 311 312 The file is read only. 313 314 315What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/raw_device_capacity 316What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/raw_device_capacity 317Date: February 2018 318Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 319Description: This file shows the total memory quantity available to 320 the user to configure the device logical units. This is one 321 of the UFS geometry descriptor parameters. The full 322 information about the descriptor could be found at 323 UFS specifications 2.1. 324 325 The file is read only. 326 327What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/max_number_of_luns 328What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/max_number_of_luns 329Date: February 2018 330Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 331Description: This file shows the maximum number of logical units 332 supported by the UFS device. This is one of the UFS 333 geometry descriptor parameters. The full information about 334 the descriptor could be found at UFS specifications 2.1. 335 336 The file is read only. 337 338What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/segment_size 339What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/segment_size 340Date: February 2018 341Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 342Description: This file shows the segment size. This is one of the UFS 343 geometry descriptor parameters. The full information about 344 the descriptor could be found at UFS specifications 2.1. 345 346 The file is read only. 347 348What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/allocation_unit_size 349What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/allocation_unit_size 350Date: February 2018 351Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 352Description: This file shows the allocation unit size. This is one of 353 the UFS geometry descriptor parameters. The full information 354 about the descriptor could be found at UFS specifications 2.1. 355 356 The file is read only. 357 358What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/min_addressable_block_size 359What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/min_addressable_block_size 360Date: February 2018 361Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 362Description: This file shows the minimum addressable block size. This 363 is one of the UFS geometry descriptor parameters. The full 364 information about the descriptor could be found at UFS 365 specifications 2.1. 366 367 The file is read only. 368 369What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/optimal_read_block_size 370What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/optimal_read_block_size 371Date: February 2018 372Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 373Description: This file shows the optimal read block size. This is one 374 of the UFS geometry descriptor parameters. The full 375 information about the descriptor could be found at UFS 376 specifications 2.1. 377 378 The file is read only. 379 380What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/optimal_write_block_size 381What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/optimal_write_block_size 382Date: February 2018 383Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 384Description: This file shows the optimal write block size. This is one 385 of the UFS geometry descriptor parameters. The full 386 information about the descriptor could be found at UFS 387 specifications 2.1. 388 389 The file is read only. 390 391What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/max_in_buffer_size 392What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/max_in_buffer_size 393Date: February 2018 394Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 395Description: This file shows the maximum data-in buffer size. This 396 is one of the UFS geometry descriptor parameters. The full 397 information about the descriptor could be found at UFS 398 specifications 2.1. 399 400 The file is read only. 401 402What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/max_out_buffer_size 403What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/max_out_buffer_size 404Date: February 2018 405Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 406Description: This file shows the maximum data-out buffer size. This 407 is one of the UFS geometry descriptor parameters. The full 408 information about the descriptor could be found at UFS 409 specifications 2.1. 410 411 The file is read only. 412 413What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/rpmb_rw_size 414What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/rpmb_rw_size 415Date: February 2018 416Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 417Description: This file shows the maximum number of RPMB frames allowed 418 in Security Protocol In/Out. This is one of the UFS geometry 419 descriptor parameters. The full information about the 420 descriptor could be found at UFS specifications 2.1. 421 422 The file is read only. 423 424What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/dyn_capacity_resource_policy 425What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/dyn_capacity_resource_policy 426Date: February 2018 427Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 428Description: This file shows the dynamic capacity resource policy. This 429 is one of the UFS geometry descriptor parameters. The full 430 information about the descriptor could be found at 431 UFS specifications 2.1. 432 433 The file is read only. 434 435What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/data_ordering 436What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/data_ordering 437Date: February 2018 438Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 439Description: This file shows support for out-of-order data transfer. 440 This is one of the UFS geometry descriptor parameters. 441 The full information about the descriptor could be found at 442 UFS specifications 2.1. 443 444 The file is read only. 445 446What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/max_number_of_contexts 447What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/max_number_of_contexts 448Date: February 2018 449Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 450Description: This file shows maximum available number of contexts which 451 are supported by the device. This is one of the UFS geometry 452 descriptor parameters. The full information about the 453 descriptor could be found at UFS specifications 2.1. 454 455 The file is read only. 456 457What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/sys_data_tag_unit_size 458What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/sys_data_tag_unit_size 459Date: February 2018 460Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 461Description: This file shows system data tag unit size. This is one of 462 the UFS geometry descriptor parameters. The full information 463 about the descriptor could be found at UFS specifications 2.1. 464 465 The file is read only. 466 467What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/sys_data_tag_resource_size 468What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/sys_data_tag_resource_size 469Date: February 2018 470Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 471Description: This file shows maximum storage area size allocated by 472 the device to handle system data by the tagging mechanism. 473 This is one of the UFS geometry descriptor parameters. 474 The full information about the descriptor could be found at 475 UFS specifications 2.1. 476 477 The file is read only. 478 479What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/secure_removal_types 480What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/secure_removal_types 481Date: February 2018 482Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 483Description: This file shows supported secure removal types. This is 484 one of the UFS geometry descriptor parameters. The full 485 information about the descriptor could be found at 486 UFS specifications 2.1. 487 488 The file is read only. 489 490What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/memory_types 491What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/memory_types 492Date: February 2018 493Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 494Description: This file shows supported memory types. This is one of 495 the UFS geometry descriptor parameters. The full 496 information about the descriptor could be found at 497 UFS specifications 2.1. 498 499 The file is read only. 500 501What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/*_memory_max_alloc_units 502What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/*_memory_max_alloc_units 503Date: February 2018 504Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 505Description: This file shows the maximum number of allocation units for 506 different memory types (system code, non persistent, 507 enhanced type 1-4). This is one of the UFS geometry 508 descriptor parameters. The full information about the 509 descriptor could be found at UFS specifications 2.1. 510 511 The file is read only. 512 513What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/*_memory_capacity_adjustment_factor 514What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/*_memory_capacity_adjustment_factor 515Date: February 2018 516Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 517Description: This file shows the memory capacity adjustment factor for 518 different memory types (system code, non persistent, 519 enhanced type 1-4). This is one of the UFS geometry 520 descriptor parameters. The full information about the 521 descriptor could be found at UFS specifications 2.1. 522 523 The file is read only. 524 525 526What: /sys/bus/platform/drivers/ufshcd/*/health_descriptor/eol_info 527What: /sys/bus/platform/devices/*.ufs/health_descriptor/eol_info 528Date: February 2018 529Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 530Description: This file shows preend of life information. This is one 531 of the UFS health descriptor parameters. The full 532 information about the descriptor could be found at 533 UFS specifications 2.1. 534 535 The file is read only. 536 537What: /sys/bus/platform/drivers/ufshcd/*/health_descriptor/life_time_estimation_a 538What: /sys/bus/platform/devices/*.ufs/health_descriptor/life_time_estimation_a 539Date: February 2018 540Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 541Description: This file shows indication of the device life time 542 (method a). This is one of the UFS health descriptor 543 parameters. The full information about the descriptor 544 could be found at UFS specifications 2.1. 545 546 The file is read only. 547 548What: /sys/bus/platform/drivers/ufshcd/*/health_descriptor/life_time_estimation_b 549What: /sys/bus/platform/devices/*.ufs/health_descriptor/life_time_estimation_b 550Date: February 2018 551Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 552Description: This file shows indication of the device life time 553 (method b). This is one of the UFS health descriptor 554 parameters. The full information about the descriptor 555 could be found at UFS specifications 2.1. 556 557 The file is read only. 558 559 560What: /sys/bus/platform/drivers/ufshcd/*/power_descriptor/active_icc_levels_vcc* 561What: /sys/bus/platform/devices/*.ufs/power_descriptor/active_icc_levels_vcc* 562Date: February 2018 563Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 564Description: This file shows maximum VCC, VCCQ and VCCQ2 value for 565 active ICC levels from 0 to 15. This is one of the UFS 566 power descriptor parameters. The full information about 567 the descriptor could be found at UFS specifications 2.1. 568 569 The file is read only. 570 571 572What: /sys/bus/platform/drivers/ufshcd/*/string_descriptors/manufacturer_name 573What: /sys/bus/platform/devices/*.ufs/string_descriptors/manufacturer_name 574Date: February 2018 575Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 576Description: This file contains a device manufacturer name string. 577 The full information about the descriptor could be found at 578 UFS specifications 2.1. 579 580 The file is read only. 581 582What: /sys/bus/platform/drivers/ufshcd/*/string_descriptors/product_name 583What: /sys/bus/platform/devices/*.ufs/string_descriptors/product_name 584Date: February 2018 585Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 586Description: This file contains a product name string. The full information 587 about the descriptor could be found at UFS specifications 2.1. 588 589 The file is read only. 590 591What: /sys/bus/platform/drivers/ufshcd/*/string_descriptors/oem_id 592What: /sys/bus/platform/devices/*.ufs/string_descriptors/oem_id 593Date: February 2018 594Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 595Description: This file contains a OEM ID string. The full information 596 about the descriptor could be found at UFS specifications 2.1. 597 598 The file is read only. 599 600What: /sys/bus/platform/drivers/ufshcd/*/string_descriptors/serial_number 601What: /sys/bus/platform/devices/*.ufs/string_descriptors/serial_number 602Date: February 2018 603Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 604Description: This file contains a device serial number string. The full 605 information about the descriptor could be found at 606 UFS specifications 2.1. 607 608 The file is read only. 609 610What: /sys/bus/platform/drivers/ufshcd/*/string_descriptors/product_revision 611What: /sys/bus/platform/devices/*.ufs/string_descriptors/product_revision 612Date: February 2018 613Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 614Description: This file contains a product revision string. The full 615 information about the descriptor could be found at 616 UFS specifications 2.1. 617 618 The file is read only. 619 620 621What: /sys/class/scsi_device/*/device/unit_descriptor/boot_lun_id 622Date: February 2018 623Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 624Description: This file shows boot LUN information. This is one of 625 the UFS unit descriptor parameters. The full information 626 about the descriptor could be found at UFS specifications 2.1. 627 628 The file is read only. 629 630What: /sys/class/scsi_device/*/device/unit_descriptor/lun_write_protect 631Date: February 2018 632Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 633Description: This file shows LUN write protection status. This is one of 634 the UFS unit descriptor parameters. The full information 635 about the descriptor could be found at UFS specifications 2.1. 636 637 The file is read only. 638 639What: /sys/class/scsi_device/*/device/unit_descriptor/lun_queue_depth 640Date: February 2018 641Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 642Description: This file shows LUN queue depth. This is one of the UFS 643 unit descriptor parameters. The full information about 644 the descriptor could be found at UFS specifications 2.1. 645 646 The file is read only. 647 648What: /sys/class/scsi_device/*/device/unit_descriptor/psa_sensitive 649Date: February 2018 650Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 651Description: This file shows PSA sensitivity. This is one of the UFS 652 unit descriptor parameters. The full information about 653 the descriptor could be found at UFS specifications 2.1. 654 655 The file is read only. 656 657What: /sys/class/scsi_device/*/device/unit_descriptor/lun_memory_type 658Date: February 2018 659Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 660Description: This file shows LUN memory type. This is one of the UFS 661 unit descriptor parameters. The full information about 662 the descriptor could be found at UFS specifications 2.1. 663 664 The file is read only. 665 666What: /sys/class/scsi_device/*/device/unit_descriptor/data_reliability 667Date: February 2018 668Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 669Description: This file defines the device behavior when a power failure 670 occurs during a write operation. This is one of the UFS 671 unit descriptor parameters. The full information about 672 the descriptor could be found at UFS specifications 2.1. 673 674 The file is read only. 675 676What: /sys/class/scsi_device/*/device/unit_descriptor/logical_block_size 677Date: February 2018 678Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 679Description: This file shows the size of addressable logical blocks 680 (calculated as an exponent with base 2). This is one of 681 the UFS unit descriptor parameters. The full information about 682 the descriptor could be found at UFS specifications 2.1. 683 684 The file is read only. 685 686What: /sys/class/scsi_device/*/device/unit_descriptor/logical_block_count 687Date: February 2018 688Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 689Description: This file shows total number of addressable logical blocks. 690 This is one of the UFS unit descriptor parameters. The full 691 information about the descriptor could be found at 692 UFS specifications 2.1. 693 694 The file is read only. 695 696What: /sys/class/scsi_device/*/device/unit_descriptor/erase_block_size 697Date: February 2018 698Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 699Description: This file shows the erase block size. This is one of 700 the UFS unit descriptor parameters. The full information 701 about the descriptor could be found at UFS specifications 2.1. 702 703 The file is read only. 704 705What: /sys/class/scsi_device/*/device/unit_descriptor/provisioning_type 706Date: February 2018 707Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 708Description: This file shows the thin provisioning type. This is one of 709 the UFS unit descriptor parameters. The full information 710 about the descriptor could be found at UFS specifications 2.1. 711 712 The file is read only. 713 714What: /sys/class/scsi_device/*/device/unit_descriptor/physical_memory_resourse_count 715Date: February 2018 716Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 717Description: This file shows the total physical memory resources. This is 718 one of the UFS unit descriptor parameters. The full information 719 about the descriptor could be found at UFS specifications 2.1. 720 721 The file is read only. 722 723What: /sys/class/scsi_device/*/device/unit_descriptor/context_capabilities 724Date: February 2018 725Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 726Description: This file shows the context capabilities. This is one of 727 the UFS unit descriptor parameters. The full information 728 about the descriptor could be found at UFS specifications 2.1. 729 730 The file is read only. 731 732What: /sys/class/scsi_device/*/device/unit_descriptor/large_unit_granularity 733Date: February 2018 734Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 735Description: This file shows the granularity of the LUN. This is one of 736 the UFS unit descriptor parameters. The full information 737 about the descriptor could be found at UFS specifications 2.1. 738 739 The file is read only. 740 741 742What: /sys/bus/platform/drivers/ufshcd/*/flags/device_init 743What: /sys/bus/platform/devices/*.ufs/flags/device_init 744Date: February 2018 745Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 746Description: This file shows the device init status. The full information 747 about the flag could be found at UFS specifications 2.1. 748 749 The file is read only. 750 751What: /sys/bus/platform/drivers/ufshcd/*/flags/permanent_wpe 752What: /sys/bus/platform/devices/*.ufs/flags/permanent_wpe 753Date: February 2018 754Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 755Description: This file shows whether permanent write protection is enabled. 756 The full information about the flag could be found at 757 UFS specifications 2.1. 758 759 The file is read only. 760 761What: /sys/bus/platform/drivers/ufshcd/*/flags/power_on_wpe 762What: /sys/bus/platform/devices/*.ufs/flags/power_on_wpe 763Date: February 2018 764Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 765Description: This file shows whether write protection is enabled on all 766 logical units configured as power on write protected. The 767 full information about the flag could be found at 768 UFS specifications 2.1. 769 770 The file is read only. 771 772What: /sys/bus/platform/drivers/ufshcd/*/flags/bkops_enable 773What: /sys/bus/platform/devices/*.ufs/flags/bkops_enable 774Date: February 2018 775Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 776Description: This file shows whether the device background operations are 777 enabled. The full information about the flag could be 778 found at UFS specifications 2.1. 779 780 The file is read only. 781 782What: /sys/bus/platform/drivers/ufshcd/*/flags/life_span_mode_enable 783What: /sys/bus/platform/devices/*.ufs/flags/life_span_mode_enable 784Date: February 2018 785Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 786Description: This file shows whether the device life span mode is enabled. 787 The full information about the flag could be found at 788 UFS specifications 2.1. 789 790 The file is read only. 791 792What: /sys/bus/platform/drivers/ufshcd/*/flags/phy_resource_removal 793What: /sys/bus/platform/devices/*.ufs/flags/phy_resource_removal 794Date: February 2018 795Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 796Description: This file shows whether physical resource removal is enable. 797 The full information about the flag could be found at 798 UFS specifications 2.1. 799 800 The file is read only. 801 802What: /sys/bus/platform/drivers/ufshcd/*/flags/busy_rtc 803What: /sys/bus/platform/devices/*.ufs/flags/busy_rtc 804Date: February 2018 805Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 806Description: This file shows whether the device is executing internal 807 operation related to real time clock. The full information 808 about the flag could be found at UFS specifications 2.1. 809 810 The file is read only. 811 812What: /sys/bus/platform/drivers/ufshcd/*/flags/disable_fw_update 813What: /sys/bus/platform/devices/*.ufs/flags/disable_fw_update 814Date: February 2018 815Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 816Description: This file shows whether the device FW update is permanently 817 disabled. The full information about the flag could be found 818 at UFS specifications 2.1. 819 820 The file is read only. 821 822 823What: /sys/bus/platform/drivers/ufshcd/*/attributes/boot_lun_enabled 824What: /sys/bus/platform/devices/*.ufs/attributes/boot_lun_enabled 825Date: February 2018 826Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 827Description: This file provides the boot lun enabled UFS device attribute. 828 The full information about the attribute could be found at 829 UFS specifications 2.1. 830 831 The file is read only. 832 833What: /sys/bus/platform/drivers/ufshcd/*/attributes/current_power_mode 834What: /sys/bus/platform/devices/*.ufs/attributes/current_power_mode 835Date: February 2018 836Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 837Description: This file provides the current power mode UFS device attribute. 838 The full information about the attribute could be found at 839 UFS specifications 2.1. 840 841 The file is read only. 842 843What: /sys/bus/platform/drivers/ufshcd/*/attributes/active_icc_level 844What: /sys/bus/platform/devices/*.ufs/attributes/active_icc_level 845Date: February 2018 846Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 847Description: This file provides the active icc level UFS device attribute. 848 The full information about the attribute could be found at 849 UFS specifications 2.1. 850 851 The file is read only. 852 853What: /sys/bus/platform/drivers/ufshcd/*/attributes/ooo_data_enabled 854What: /sys/bus/platform/devices/*.ufs/attributes/ooo_data_enabled 855Date: February 2018 856Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 857Description: This file provides the out of order data transfer enabled UFS 858 device attribute. The full information about the attribute 859 could be found at UFS specifications 2.1. 860 861 The file is read only. 862 863What: /sys/bus/platform/drivers/ufshcd/*/attributes/bkops_status 864What: /sys/bus/platform/devices/*.ufs/attributes/bkops_status 865Date: February 2018 866Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 867Description: This file provides the background operations status UFS device 868 attribute. The full information about the attribute could 869 be found at UFS specifications 2.1. 870 871 The file is read only. 872 873What: /sys/bus/platform/drivers/ufshcd/*/attributes/purge_status 874What: /sys/bus/platform/devices/*.ufs/attributes/purge_status 875Date: February 2018 876Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 877Description: This file provides the purge operation status UFS device 878 attribute. The full information about the attribute could 879 be found at UFS specifications 2.1. 880 881 The file is read only. 882 883What: /sys/bus/platform/drivers/ufshcd/*/attributes/max_data_in_size 884What: /sys/bus/platform/devices/*.ufs/attributes/max_data_in_size 885Date: February 2018 886Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 887Description: This file shows the maximum data size in a DATA IN 888 UPIU. The full information about the attribute could 889 be found at UFS specifications 2.1. 890 891 The file is read only. 892 893What: /sys/bus/platform/drivers/ufshcd/*/attributes/max_data_out_size 894What: /sys/bus/platform/devices/*.ufs/attributes/max_data_out_size 895Date: February 2018 896Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 897Description: This file shows the maximum number of bytes that can be 898 requested with a READY TO TRANSFER UPIU. The full information 899 about the attribute could be found at UFS specifications 2.1. 900 901 The file is read only. 902 903What: /sys/bus/platform/drivers/ufshcd/*/attributes/reference_clock_frequency 904What: /sys/bus/platform/devices/*.ufs/attributes/reference_clock_frequency 905Date: February 2018 906Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 907Description: This file provides the reference clock frequency UFS device 908 attribute. The full information about the attribute could 909 be found at UFS specifications 2.1. 910 911 The file is read only. 912 913What: /sys/bus/platform/drivers/ufshcd/*/attributes/configuration_descriptor_lock 914What: /sys/bus/platform/devices/*.ufs/attributes/configuration_descriptor_lock 915Date: February 2018 916Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 917Description: This file shows whether the configuration descriptor is locked. 918 The full information about the attribute could be found at 919 UFS specifications 2.1. The file is read only. 920 921What: /sys/bus/platform/drivers/ufshcd/*/attributes/max_number_of_rtt 922What: /sys/bus/platform/devices/*.ufs/attributes/max_number_of_rtt 923Date: February 2018 924Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 925Description: This file provides the maximum current number of 926 outstanding RTTs in device that is allowed. The full 927 information about the attribute could be found at 928 UFS specifications 2.1. 929 930 The file is read only. 931 932What: /sys/bus/platform/drivers/ufshcd/*/attributes/exception_event_control 933What: /sys/bus/platform/devices/*.ufs/attributes/exception_event_control 934Date: February 2018 935Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 936Description: This file provides the exception event control UFS device 937 attribute. The full information about the attribute could 938 be found at UFS specifications 2.1. 939 940 The file is read only. 941 942What: /sys/bus/platform/drivers/ufshcd/*/attributes/exception_event_status 943What: /sys/bus/platform/devices/*.ufs/attributes/exception_event_status 944Date: February 2018 945Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 946Description: This file provides the exception event status UFS device 947 attribute. The full information about the attribute could 948 be found at UFS specifications 2.1. 949 950 The file is read only. 951 952What: /sys/bus/platform/drivers/ufshcd/*/attributes/ffu_status 953What: /sys/bus/platform/devices/*.ufs/attributes/ffu_status 954Date: February 2018 955Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 956Description: This file provides the ffu status UFS device attribute. 957 The full information about the attribute could be found at 958 UFS specifications 2.1. 959 960 The file is read only. 961 962What: /sys/bus/platform/drivers/ufshcd/*/attributes/psa_state 963What: /sys/bus/platform/devices/*.ufs/attributes/psa_state 964Date: February 2018 965Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 966Description: This file show the PSA feature status. The full information 967 about the attribute could be found at UFS specifications 2.1. 968 969 The file is read only. 970 971What: /sys/bus/platform/drivers/ufshcd/*/attributes/psa_data_size 972What: /sys/bus/platform/devices/*.ufs/attributes/psa_data_size 973Date: February 2018 974Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 975Description: This file shows the amount of data that the host plans to 976 load to all logical units in pre-soldering state. 977 The full information about the attribute could be found at 978 UFS specifications 2.1. 979 980 The file is read only. 981 982 983What: /sys/class/scsi_device/*/device/dyn_cap_needed 984Date: February 2018 985Contact: Stanislav Nijnikov <stanislav.nijnikov@wdc.com> 986Description: This file shows the amount of physical memory needed 987 to be removed from the physical memory resources pool of 988 the particular logical unit. The full information about 989 the attribute could be found at UFS specifications 2.1. 990 991 The file is read only. 992 993 994What: /sys/bus/platform/drivers/ufshcd/*/rpm_lvl 995What: /sys/bus/platform/devices/*.ufs/rpm_lvl 996Date: September 2014 997Contact: Subhash Jadavani <subhashj@codeaurora.org> 998Description: This entry could be used to set or show the UFS device 999 runtime power management level. The current driver 1000 implementation supports 7 levels with next target states: 1001 1002 == ==================================================== 1003 0 UFS device will stay active, UIC link will 1004 stay active 1005 1 UFS device will stay active, UIC link will 1006 hibernate 1007 2 UFS device will be moved to sleep, UIC link will 1008 stay active 1009 3 UFS device will be moved to sleep, UIC link will 1010 hibernate 1011 4 UFS device will be powered off, UIC link will 1012 hibernate 1013 5 UFS device will be powered off, UIC link will 1014 be powered off 1015 6 UFS device will be moved to deep sleep, UIC link 1016 will be powered off. Note, deep sleep might not be 1017 supported in which case this value will not be 1018 accepted 1019 == ==================================================== 1020 1021What: /sys/bus/platform/drivers/ufshcd/*/rpm_target_dev_state 1022What: /sys/bus/platform/devices/*.ufs/rpm_target_dev_state 1023Date: February 2018 1024Contact: Subhash Jadavani <subhashj@codeaurora.org> 1025Description: This entry shows the target power mode of an UFS device 1026 for the chosen runtime power management level. 1027 1028 The file is read only. 1029 1030What: /sys/bus/platform/drivers/ufshcd/*/rpm_target_link_state 1031What: /sys/bus/platform/devices/*.ufs/rpm_target_link_state 1032Date: February 2018 1033Contact: Subhash Jadavani <subhashj@codeaurora.org> 1034Description: This entry shows the target state of an UFS UIC link 1035 for the chosen runtime power management level. 1036 1037 The file is read only. 1038 1039What: /sys/bus/platform/drivers/ufshcd/*/spm_lvl 1040What: /sys/bus/platform/devices/*.ufs/spm_lvl 1041Date: September 2014 1042Contact: Subhash Jadavani <subhashj@codeaurora.org> 1043Description: This entry could be used to set or show the UFS device 1044 system power management level. The current driver 1045 implementation supports 7 levels with next target states: 1046 1047 == ==================================================== 1048 0 UFS device will stay active, UIC link will 1049 stay active 1050 1 UFS device will stay active, UIC link will 1051 hibernate 1052 2 UFS device will be moved to sleep, UIC link will 1053 stay active 1054 3 UFS device will be moved to sleep, UIC link will 1055 hibernate 1056 4 UFS device will be powered off, UIC link will 1057 hibernate 1058 5 UFS device will be powered off, UIC link will 1059 be powered off 1060 6 UFS device will be moved to deep sleep, UIC link 1061 will be powered off. Note, deep sleep might not be 1062 supported in which case this value will not be 1063 accepted 1064 == ==================================================== 1065 1066What: /sys/bus/platform/drivers/ufshcd/*/spm_target_dev_state 1067What: /sys/bus/platform/devices/*.ufs/spm_target_dev_state 1068Date: February 2018 1069Contact: Subhash Jadavani <subhashj@codeaurora.org> 1070Description: This entry shows the target power mode of an UFS device 1071 for the chosen system power management level. 1072 1073 The file is read only. 1074 1075What: /sys/bus/platform/drivers/ufshcd/*/spm_target_link_state 1076What: /sys/bus/platform/devices/*.ufs/spm_target_link_state 1077Date: February 2018 1078Contact: Subhash Jadavani <subhashj@codeaurora.org> 1079Description: This entry shows the target state of an UFS UIC link 1080 for the chosen system power management level. 1081 1082 The file is read only. 1083 1084What: /sys/bus/platform/drivers/ufshcd/*/monitor/monitor_enable 1085What: /sys/bus/platform/devices/*.ufs/monitor/monitor_enable 1086Date: January 2021 1087Contact: Can Guo <cang@codeaurora.org> 1088Description: This file shows the status of performance monitor enablement 1089 and it can be used to start/stop the monitor. When the monitor 1090 is stopped, the performance data collected is also cleared. 1091 1092What: /sys/bus/platform/drivers/ufshcd/*/monitor/monitor_chunk_size 1093What: /sys/bus/platform/devices/*.ufs/monitor/monitor_chunk_size 1094Date: January 2021 1095Contact: Can Guo <cang@codeaurora.org> 1096Description: This file tells the monitor to focus on requests transferring 1097 data of specific chunk size (in Bytes). 0 means any chunk size. 1098 It can only be changed when monitor is disabled. 1099 1100What: /sys/bus/platform/drivers/ufshcd/*/monitor/read_total_sectors 1101What: /sys/bus/platform/devices/*.ufs/monitor/read_total_sectors 1102Date: January 2021 1103Contact: Can Guo <cang@codeaurora.org> 1104Description: This file shows how many sectors (in 512 Bytes) have been 1105 sent from device to host after monitor gets started. 1106 1107 The file is read only. 1108 1109What: /sys/bus/platform/drivers/ufshcd/*/monitor/read_total_busy 1110What: /sys/bus/platform/devices/*.ufs/monitor/read_total_busy 1111Date: January 2021 1112Contact: Can Guo <cang@codeaurora.org> 1113Description: This file shows how long (in micro seconds) has been spent 1114 sending data from device to host after monitor gets started. 1115 1116 The file is read only. 1117 1118What: /sys/bus/platform/drivers/ufshcd/*/monitor/read_nr_requests 1119What: /sys/bus/platform/devices/*.ufs/monitor/read_nr_requests 1120Date: January 2021 1121Contact: Can Guo <cang@codeaurora.org> 1122Description: This file shows how many read requests have been sent after 1123 monitor gets started. 1124 1125 The file is read only. 1126 1127What: /sys/bus/platform/drivers/ufshcd/*/monitor/read_req_latency_max 1128What: /sys/bus/platform/devices/*.ufs/monitor/read_req_latency_max 1129Date: January 2021 1130Contact: Can Guo <cang@codeaurora.org> 1131Description: This file shows the maximum latency (in micro seconds) of 1132 read requests after monitor gets started. 1133 1134 The file is read only. 1135 1136What: /sys/bus/platform/drivers/ufshcd/*/monitor/read_req_latency_min 1137What: /sys/bus/platform/devices/*.ufs/monitor/read_req_latency_min 1138Date: January 2021 1139Contact: Can Guo <cang@codeaurora.org> 1140Description: This file shows the minimum latency (in micro seconds) of 1141 read requests after monitor gets started. 1142 1143 The file is read only. 1144 1145What: /sys/bus/platform/drivers/ufshcd/*/monitor/read_req_latency_avg 1146What: /sys/bus/platform/devices/*.ufs/monitor/read_req_latency_avg 1147Date: January 2021 1148Contact: Can Guo <cang@codeaurora.org> 1149Description: This file shows the average latency (in micro seconds) of 1150 read requests after monitor gets started. 1151 1152 The file is read only. 1153 1154What: /sys/bus/platform/drivers/ufshcd/*/monitor/read_req_latency_sum 1155What: /sys/bus/platform/devices/*.ufs/monitor/read_req_latency_sum 1156Date: January 2021 1157Contact: Can Guo <cang@codeaurora.org> 1158Description: This file shows the total latency (in micro seconds) of 1159 read requests sent after monitor gets started. 1160 1161 The file is read only. 1162 1163What: /sys/bus/platform/drivers/ufshcd/*/monitor/write_total_sectors 1164What: /sys/bus/platform/devices/*.ufs/monitor/write_total_sectors 1165Date: January 2021 1166Contact: Can Guo <cang@codeaurora.org> 1167Description: This file shows how many sectors (in 512 Bytes) have been sent 1168 from host to device after monitor gets started. 1169 1170 The file is read only. 1171 1172What: /sys/bus/platform/drivers/ufshcd/*/monitor/write_total_busy 1173What: /sys/bus/platform/devices/*.ufs/monitor/write_total_busy 1174Date: January 2021 1175Contact: Can Guo <cang@codeaurora.org> 1176Description: This file shows how long (in micro seconds) has been spent 1177 sending data from host to device after monitor gets started. 1178 1179 The file is read only. 1180 1181What: /sys/bus/platform/drivers/ufshcd/*/monitor/write_nr_requests 1182What: /sys/bus/platform/devices/*.ufs/monitor/write_nr_requests 1183Date: January 2021 1184Contact: Can Guo <cang@codeaurora.org> 1185Description: This file shows how many write requests have been sent after 1186 monitor gets started. 1187 1188 The file is read only. 1189 1190What: /sys/bus/platform/drivers/ufshcd/*/monitor/write_req_latency_max 1191What: /sys/bus/platform/devices/*.ufs/monitor/write_req_latency_max 1192Date: January 2021 1193Contact: Can Guo <cang@codeaurora.org> 1194Description: This file shows the maximum latency (in micro seconds) of write 1195 requests after monitor gets started. 1196 1197 The file is read only. 1198 1199What: /sys/bus/platform/drivers/ufshcd/*/monitor/write_req_latency_min 1200What: /sys/bus/platform/devices/*.ufs/monitor/write_req_latency_min 1201Date: January 2021 1202Contact: Can Guo <cang@codeaurora.org> 1203Description: This file shows the minimum latency (in micro seconds) of write 1204 requests after monitor gets started. 1205 1206 The file is read only. 1207 1208What: /sys/bus/platform/drivers/ufshcd/*/monitor/write_req_latency_avg 1209What: /sys/bus/platform/devices/*.ufs/monitor/write_req_latency_avg 1210Date: January 2021 1211Contact: Can Guo <cang@codeaurora.org> 1212Description: This file shows the average latency (in micro seconds) of write 1213 requests after monitor gets started. 1214 1215 The file is read only. 1216 1217What: /sys/bus/platform/drivers/ufshcd/*/monitor/write_req_latency_sum 1218What: /sys/bus/platform/devices/*.ufs/monitor/write_req_latency_sum 1219Date: January 2021 1220Contact: Can Guo <cang@codeaurora.org> 1221Description: This file shows the total latency (in micro seconds) of write 1222 requests after monitor gets started. 1223 1224 The file is read only. 1225 1226What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/wb_presv_us_en 1227What: /sys/bus/platform/devices/*.ufs/device_descriptor/wb_presv_us_en 1228Date: June 2020 1229Contact: Asutosh Das <asutoshd@codeaurora.org> 1230Description: This entry shows if preserve user-space was configured 1231 1232 The file is read only. 1233 1234What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/wb_shared_alloc_units 1235What: /sys/bus/platform/devices/*.ufs/device_descriptor/wb_shared_alloc_units 1236Date: June 2020 1237Contact: Asutosh Das <asutoshd@codeaurora.org> 1238Description: This entry shows the shared allocated units of WB buffer 1239 1240 The file is read only. 1241 1242What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/wb_type 1243What: /sys/bus/platform/devices/*.ufs/device_descriptor/wb_type 1244Date: June 2020 1245Contact: Asutosh Das <asutoshd@codeaurora.org> 1246Description: This entry shows the configured WB type. 1247 0x1 for shared buffer mode. 0x0 for dedicated buffer mode. 1248 1249 The file is read only. 1250 1251What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/wb_buff_cap_adj 1252What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/wb_buff_cap_adj 1253Date: June 2020 1254Contact: Asutosh Das <asutoshd@codeaurora.org> 1255Description: This entry shows the total user-space decrease in shared 1256 buffer mode. 1257 The value of this parameter is 3 for TLC NAND when SLC mode 1258 is used as WriteBooster Buffer. 2 for MLC NAND. 1259 1260 The file is read only. 1261 1262What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/wb_max_alloc_units 1263What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/wb_max_alloc_units 1264Date: June 2020 1265Contact: Asutosh Das <asutoshd@codeaurora.org> 1266Description: This entry shows the Maximum total WriteBooster Buffer size 1267 which is supported by the entire device. 1268 1269 The file is read only. 1270 1271What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/wb_max_wb_luns 1272What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/wb_max_wb_luns 1273Date: June 2020 1274Contact: Asutosh Das <asutoshd@codeaurora.org> 1275Description: This entry shows the maximum number of luns that can support 1276 WriteBooster. 1277 1278 The file is read only. 1279 1280What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/wb_sup_red_type 1281What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/wb_sup_red_type 1282Date: June 2020 1283Contact: Asutosh Das <asutoshd@codeaurora.org> 1284Description: The supportability of user space reduction mode 1285 and preserve user space mode. 1286 00h: WriteBooster Buffer can be configured only in 1287 user space reduction type. 1288 01h: WriteBooster Buffer can be configured only in 1289 preserve user space type. 1290 02h: Device can be configured in either user space 1291 reduction type or preserve user space type. 1292 1293 The file is read only. 1294 1295What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/wb_sup_wb_type 1296What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/wb_sup_wb_type 1297Date: June 2020 1298Contact: Asutosh Das <asutoshd@codeaurora.org> 1299Description: The supportability of WriteBooster Buffer type. 1300 1301 === ========================================================== 1302 00h LU based WriteBooster Buffer configuration 1303 01h Single shared WriteBooster Buffer configuration 1304 02h Supporting both LU based WriteBooster. 1305 Buffer and Single shared WriteBooster Buffer configuration 1306 === ========================================================== 1307 1308 The file is read only. 1309 1310What: /sys/bus/platform/drivers/ufshcd/*/flags/wb_enable 1311What: /sys/bus/platform/devices/*.ufs/flags/wb_enable 1312Date: June 2020 1313Contact: Asutosh Das <asutoshd@codeaurora.org> 1314Description: This entry shows the status of WriteBooster. 1315 1316 == ============================ 1317 0 WriteBooster is not enabled. 1318 1 WriteBooster is enabled 1319 == ============================ 1320 1321 The file is read only. 1322 1323What: /sys/bus/platform/drivers/ufshcd/*/flags/wb_flush_en 1324What: /sys/bus/platform/devices/*.ufs/flags/wb_flush_en 1325Date: June 2020 1326Contact: Asutosh Das <asutoshd@codeaurora.org> 1327Description: This entry shows if flush is enabled. 1328 1329 == ================================= 1330 0 Flush operation is not performed. 1331 1 Flush operation is performed. 1332 == ================================= 1333 1334 The file is read only. 1335 1336What: /sys/bus/platform/drivers/ufshcd/*/flags/wb_flush_during_h8 1337What: /sys/bus/platform/devices/*.ufs/flags/wb_flush_during_h8 1338Date: June 2020 1339Contact: Asutosh Das <asutoshd@codeaurora.org> 1340Description: Flush WriteBooster Buffer during hibernate state. 1341 1342 == ================================================= 1343 0 Device is not allowed to flush the 1344 WriteBooster Buffer during link hibernate state. 1345 1 Device is allowed to flush the 1346 WriteBooster Buffer during link hibernate state. 1347 == ================================================= 1348 1349 The file is read only. 1350 1351What: /sys/bus/platform/drivers/ufshcd/*/attributes/wb_avail_buf 1352What: /sys/bus/platform/devices/*.ufs/attributes/wb_avail_buf 1353Date: June 2020 1354Contact: Asutosh Das <asutoshd@codeaurora.org> 1355Description: This entry shows the amount of unused WriteBooster buffer 1356 available. 1357 1358 The file is read only. 1359 1360What: /sys/bus/platform/drivers/ufshcd/*/attributes/wb_cur_buf 1361What: /sys/bus/platform/devices/*.ufs/attributes/wb_cur_buf 1362Date: June 2020 1363Contact: Asutosh Das <asutoshd@codeaurora.org> 1364Description: This entry shows the amount of unused current buffer. 1365 1366 The file is read only. 1367 1368What: /sys/bus/platform/drivers/ufshcd/*/attributes/wb_flush_status 1369What: /sys/bus/platform/devices/*.ufs/attributes/wb_flush_status 1370Date: June 2020 1371Contact: Asutosh Das <asutoshd@codeaurora.org> 1372Description: This entry shows the flush operation status. 1373 1374 1375 === ====================================== 1376 00h idle 1377 01h Flush operation in progress 1378 02h Flush operation stopped prematurely. 1379 03h Flush operation completed successfully 1380 04h Flush operation general failure 1381 === ====================================== 1382 1383 The file is read only. 1384 1385What: /sys/bus/platform/drivers/ufshcd/*/attributes/wb_life_time_est 1386What: /sys/bus/platform/devices/*.ufs/attributes/wb_life_time_est 1387Date: June 2020 1388Contact: Asutosh Das <asutoshd@codeaurora.org> 1389Description: This entry shows an indication of the WriteBooster Buffer 1390 lifetime based on the amount of performed program/erase cycles 1391 1392 === ============================================= 1393 01h 0% - 10% WriteBooster Buffer life time used 1394 ... 1395 0Ah 90% - 100% WriteBooster Buffer life time used 1396 === ============================================= 1397 1398 The file is read only. 1399 1400What: /sys/class/scsi_device/*/device/unit_descriptor/wb_buf_alloc_units 1401Date: June 2020 1402Contact: Asutosh Das <asutoshd@codeaurora.org> 1403Description: This entry shows the configured size of WriteBooster buffer. 1404 0400h corresponds to 4GB. 1405 1406 The file is read only. 1407 1408What: /sys/bus/platform/drivers/ufshcd/*/wb_on 1409What: /sys/bus/platform/devices/*.ufs/wb_on 1410Date: January 2021 1411Contact: Bean Huo <beanhuo@micron.com> 1412Description: This node is used to set or display whether UFS WriteBooster is 1413 enabled. Echo 0 to this file to disable UFS WriteBooster or 1 to 1414 enable it. The WriteBooster is enabled after power-on/reset, 1415 however, it will be disabled/enable while CLK scaling down/up 1416 (if the platform supports UFSHCD_CAP_CLK_SCALING). For a 1417 platform that doesn't support UFSHCD_CAP_CLK_SCALING, we can 1418 disable/enable WriteBooster through this sysfs node. 1419 1420What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/hpb_version 1421What: /sys/bus/platform/devices/*.ufs/device_descriptor/hpb_version 1422Date: June 2021 1423Contact: Daejun Park <daejun7.park@samsung.com> 1424Description: This entry shows the HPB specification version. 1425 The full information about the descriptor can be found in the UFS 1426 HPB (Host Performance Booster) Extension specifications. 1427 Example: version 1.2.3 = 0123h 1428 1429 The file is read only. 1430 1431What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/hpb_control 1432What: /sys/bus/platform/devices/*.ufs/device_descriptor/hpb_control 1433Date: June 2021 1434Contact: Daejun Park <daejun7.park@samsung.com> 1435Description: This entry shows an indication of the HPB control mode. 1436 00h: Host control mode 1437 01h: Device control mode 1438 1439 The file is read only. 1440 1441What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/hpb_region_size 1442What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/hpb_region_size 1443Date: June 2021 1444Contact: Daejun Park <daejun7.park@samsung.com> 1445Description: This entry shows the bHPBRegionSize which can be calculated 1446 as in the following (in bytes): 1447 HPB Region size = 512B * 2^bHPBRegionSize 1448 1449 The file is read only. 1450 1451What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/hpb_number_lu 1452What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/hpb_number_lu 1453Date: June 2021 1454Contact: Daejun Park <daejun7.park@samsung.com> 1455Description: This entry shows the maximum number of HPB LU supported by 1456 the device. 1457 00h: HPB is not supported by the device. 1458 01h ~ 20h: Maximum number of HPB LU supported by the device 1459 1460 The file is read only. 1461 1462What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/hpb_subregion_size 1463What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/hpb_subregion_size 1464Date: June 2021 1465Contact: Daejun Park <daejun7.park@samsung.com> 1466Description: This entry shows the bHPBSubRegionSize, which can be 1467 calculated as in the following (in bytes) and shall be a multiple of 1468 logical block size: 1469 HPB Sub-Region size = 512B x 2^bHPBSubRegionSize 1470 bHPBSubRegionSize shall not exceed bHPBRegionSize. 1471 1472 The file is read only. 1473 1474What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/hpb_max_active_regions 1475What: /sys/bus/platform/devices/*.ufs/geometry_descriptor/hpb_max_active_regions 1476Date: June 2021 1477Contact: Daejun Park <daejun7.park@samsung.com> 1478Description: This entry shows the maximum number of active HPB regions that 1479 is supported by the device. 1480 1481 The file is read only. 1482 1483What: /sys/class/scsi_device/*/device/unit_descriptor/hpb_lu_max_active_regions 1484Date: June 2021 1485Contact: Daejun Park <daejun7.park@samsung.com> 1486Description: This entry shows the maximum number of HPB regions assigned to 1487 the HPB logical unit. 1488 1489 The file is read only. 1490 1491What: /sys/class/scsi_device/*/device/unit_descriptor/hpb_pinned_region_start_offset 1492Date: June 2021 1493Contact: Daejun Park <daejun7.park@samsung.com> 1494Description: This entry shows the start offset of HPB pinned region. 1495 1496 The file is read only. 1497 1498What: /sys/class/scsi_device/*/device/unit_descriptor/hpb_number_pinned_regions 1499Date: June 2021 1500Contact: Daejun Park <daejun7.park@samsung.com> 1501Description: This entry shows the number of HPB pinned regions assigned to 1502 the HPB logical unit. 1503 1504 The file is read only. 1505 1506What: /sys/class/scsi_device/*/device/hpb_stats/hit_cnt 1507Date: June 2021 1508Contact: Daejun Park <daejun7.park@samsung.com> 1509Description: This entry shows the number of reads that changed to HPB read. 1510 1511 The file is read only. 1512 1513What: /sys/class/scsi_device/*/device/hpb_stats/miss_cnt 1514Date: June 2021 1515Contact: Daejun Park <daejun7.park@samsung.com> 1516Description: This entry shows the number of reads that cannot be changed to 1517 HPB read. 1518 1519 The file is read only. 1520 1521What: /sys/class/scsi_device/*/device/hpb_stats/rcmd_noti_cnt 1522Date: June 2021 1523Contact: Daejun Park <daejun7.park@samsung.com> 1524Description: This entry shows the number of response UPIUs that has 1525 recommendations for activating sub-regions and/or inactivating region. 1526 1527 The file is read only. 1528 1529What: /sys/class/scsi_device/*/device/hpb_stats/rcmd_active_cnt 1530Date: June 2021 1531Contact: Daejun Park <daejun7.park@samsung.com> 1532Description: For the HPB device control mode, this entry shows the number of 1533 active sub-regions recommended by response UPIUs. For the HPB host control 1534 mode, this entry shows the number of active sub-regions recommended by the 1535 HPB host control mode heuristic algorithm. 1536 1537 The file is read only. 1538 1539What: /sys/class/scsi_device/*/device/hpb_stats/rcmd_inactive_cnt 1540Date: June 2021 1541Contact: Daejun Park <daejun7.park@samsung.com> 1542Description: For the HPB device control mode, this entry shows the number of 1543 inactive regions recommended by response UPIUs. For the HPB host control 1544 mode, this entry shows the number of inactive regions recommended by the 1545 HPB host control mode heuristic algorithm. 1546 1547 The file is read only. 1548 1549What: /sys/class/scsi_device/*/device/hpb_stats/map_req_cnt 1550Date: June 2021 1551Contact: Daejun Park <daejun7.park@samsung.com> 1552Description: This entry shows the number of read buffer commands for 1553 activating sub-regions recommended by response UPIUs. 1554 1555 The file is read only. 1556 1557What: /sys/class/scsi_device/*/device/hpb_params/requeue_timeout_ms 1558Date: June 2021 1559Contact: Daejun Park <daejun7.park@samsung.com> 1560Description: This entry shows the requeue timeout threshold for write buffer 1561 command in ms. The value can be changed by writing an integer to 1562 this entry. 1563 1564What: /sys/bus/platform/drivers/ufshcd/*/attributes/max_data_size_hpb_single_cmd 1565What: /sys/bus/platform/devices/*.ufs/attributes/max_data_size_hpb_single_cmd 1566Date: June 2021 1567Contact: Daejun Park <daejun7.park@samsung.com> 1568Description: This entry shows the maximum HPB data size for using a single HPB 1569 command. 1570 1571 === ======== 1572 00h 4KB 1573 01h 8KB 1574 02h 12KB 1575 ... 1576 FFh 1024KB 1577 === ======== 1578 1579 The file is read only. 1580 1581What: /sys/bus/platform/drivers/ufshcd/*/flags/hpb_enable 1582What: /sys/bus/platform/devices/*.ufs/flags/hpb_enable 1583Date: June 2021 1584Contact: Daejun Park <daejun7.park@samsung.com> 1585Description: This entry shows the status of HPB. 1586 1587 == ============================ 1588 0 HPB is not enabled. 1589 1 HPB is enabled 1590 == ============================ 1591 1592 The file is read only. 1593 1594What: /sys/class/scsi_device/*/device/hpb_param_sysfs/activation_thld 1595Date: February 2021 1596Contact: Avri Altman <avri.altman@wdc.com> 1597Description: In host control mode, reads are the major source of activation 1598 trials. Once this threshold hs met, the region is added to the 1599 "to-be-activated" list. Since we reset the read counter upon 1600 write, this include sending a rb command updating the region 1601 ppn as well. 1602 1603What: /sys/class/scsi_device/*/device/hpb_param_sysfs/normalization_factor 1604Date: February 2021 1605Contact: Avri Altman <avri.altman@wdc.com> 1606Description: In host control mode, we think of the regions as "buckets". 1607 Those buckets are being filled with reads, and emptied on write. 1608 We use entries_per_srgn - the amount of blocks in a subregion as 1609 our bucket size. This applies because HPB1.0 only handles 1610 single-block reads. Once the bucket size is crossed, we trigger 1611 a normalization work - not only to avoid overflow, but mainly 1612 because we want to keep those counters normalized, as we are 1613 using those reads as a comparative score, to make various decisions. 1614 The normalization is dividing (shift right) the read counter by 1615 the normalization_factor. If during consecutive normalizations 1616 an active region has exhausted its reads - inactivate it. 1617 1618What: /sys/class/scsi_device/*/device/hpb_param_sysfs/eviction_thld_enter 1619Date: February 2021 1620Contact: Avri Altman <avri.altman@wdc.com> 1621Description: Region deactivation is often due to the fact that eviction took 1622 place: A region becomes active at the expense of another. This is 1623 happening when the max-active-regions limit has been crossed. 1624 In host mode, eviction is considered an extreme measure. We 1625 want to verify that the entering region has enough reads, and 1626 the exiting region has much fewer reads. eviction_thld_enter is 1627 the min reads that a region must have in order to be considered 1628 a candidate for evicting another region. 1629 1630What: /sys/class/scsi_device/*/device/hpb_param_sysfs/eviction_thld_exit 1631Date: February 2021 1632Contact: Avri Altman <avri.altman@wdc.com> 1633Description: Same as above for the exiting region. A region is considered to 1634 be a candidate for eviction only if it has fewer reads than 1635 eviction_thld_exit. 1636 1637What: /sys/class/scsi_device/*/device/hpb_param_sysfs/read_timeout_ms 1638Date: February 2021 1639Contact: Avri Altman <avri.altman@wdc.com> 1640Description: In order not to hang on to "cold" regions, we inactivate 1641 a region that has no READ access for a predefined amount of 1642 time - read_timeout_ms. If read_timeout_ms has expired, and the 1643 region is dirty, it is less likely that we can make any use of 1644 HPB reading it so we inactivate it. Still, deactivation has 1645 its overhead, and we may still benefit from HPB reading this 1646 region if it is clean - see read_timeout_expiries. 1647 1648What: /sys/class/scsi_device/*/device/hpb_param_sysfs/read_timeout_expiries 1649Date: February 2021 1650Contact: Avri Altman <avri.altman@wdc.com> 1651Description: If the region read timeout has expired, but the region is clean, 1652 just re-wind its timer for another spin. Do that as long as it 1653 is clean and did not exhaust its read_timeout_expiries threshold. 1654 1655What: /sys/class/scsi_device/*/device/hpb_param_sysfs/timeout_polling_interval_ms 1656Date: February 2021 1657Contact: Avri Altman <avri.altman@wdc.com> 1658Description: The frequency with which the delayed worker that checks the 1659 read_timeouts is awakened. 1660 1661What: /sys/class/scsi_device/*/device/hpb_param_sysfs/inflight_map_req 1662Date: February 2021 1663Contact: Avri Altman <avri.altman@wdc.com> 1664Description: In host control mode the host is the originator of map requests. 1665 To avoid flooding the device with map requests, use a simple throttling 1666 mechanism that limits the number of inflight map requests.