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Documentation: cpufreq: amd-pstate: Update amd_pstate status sysfs for guided

Update amd_pstate status sysfs for guided mode.

Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

authored by

Wyes Karny and committed by
Rafael J. Wysocki
7a9dec66 3ca7bc81

+24 -7
+24 -7
Documentation/admin-guide/pm/amd-pstate.rst
··· 303 303 AMD Pstate Driver Operation Modes 304 304 ================================= 305 305 306 - ``amd_pstate`` CPPC has two operation modes: CPPC Autonomous(active) mode and 307 - CPPC non-autonomous(passive) mode. 308 - active mode and passive mode can be chosen by different kernel parameters. 309 - When in Autonomous mode, CPPC ignores requests done in the Desired Performance 310 - Target register and takes into account only the values set to the Minimum requested 311 - performance, Maximum requested performance, and Energy Performance Preference 312 - registers. When Autonomous is disabled, it only considers the Desired Performance Target. 306 + ``amd_pstate`` CPPC has 3 operation modes: autonomous (active) mode, 307 + non-autonomous (passive) mode and guided autonomous (guided) mode. 308 + Active/passive/guided mode can be chosen by different kernel parameters. 309 + 310 + - In autonomous mode, platform ignores the desired performance level request 311 + and takes into account only the values set to the minimum, maximum and energy 312 + performance preference registers. 313 + - In non-autonomous mode, platform gets desired performance level 314 + from OS directly through Desired Performance Register. 315 + - In guided-autonomous mode, platform sets operating performance level 316 + autonomously according to the current workload and within the limits set by 317 + OS through min and max performance registers. 313 318 314 319 Active Mode 315 320 ------------ ··· 343 338 processor must provide at least nominal performance requested and go higher if current 344 339 operating conditions allow. 345 340 341 + Guided Mode 342 + ----------- 343 + 344 + ``amd_pstate=guided`` 345 + 346 + If ``amd_pstate=guided`` is passed to kernel command line option then this mode 347 + is activated. In this mode, driver requests minimum and maximum performance 348 + level and the platform autonomously selects a performance level in this range 349 + and appropriate to the current workload. 346 350 347 351 User Space Interface in ``sysfs`` - General 348 352 =========================================== ··· 371 357 372 358 "passive" 373 359 The driver is functional and in the ``passive mode`` 360 + 361 + "guided" 362 + The driver is functional and in the ``guided mode`` 374 363 375 364 "disable" 376 365 The driver is unregistered and not functional now.