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From: Perry Yuan <perry.yuan@amd.com>
To: <rafael.j.wysocki@intel.com>, <Mario.Limonciello@amd.com>,
	<viresh.kumar@linaro.org>, <Ray.Huang@amd.com>,
	<gautham.shenoy@amd.com>, <Borislav.Petkov@amd.com>
Cc: <Alexander.Deucher@amd.com>, <Xinmei.Huang@amd.com>,
	<Xiaojian.Du@amd.com>, <Li.Meng@amd.com>,
	<linux-pm@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: [PATCH v10 7/7] Documentation: cpufreq: amd-pstate: update doc for Per CPU boost control method
Date: Wed, 8 May 2024 15:21:12 +0800	[thread overview]
Message-ID: <8661e4fb9a0473bbe74fd9ad008e19380743b46d.1715152592.git.perry.yuan@amd.com> (raw)
In-Reply-To: <cover.1715152592.git.perry.yuan@amd.com>

Updates the documentation in `amd-pstate.rst` to include information about the
per CPU boost control feature. Users can now enable or disable the Core Performance
Boost (CPB) feature on individual CPUs using the `boost` sysfs attribute.

Signed-off-by: Perry Yuan <perry.yuan@amd.com>
---
 Documentation/admin-guide/pm/amd-pstate.rst | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst
index bcc0d9404c18..98e43c53c387 100644
--- a/Documentation/admin-guide/pm/amd-pstate.rst
+++ b/Documentation/admin-guide/pm/amd-pstate.rst
@@ -281,6 +281,26 @@ integer values defined between 0 to 255 when EPP feature is enabled by platform
 firmware, if EPP feature is disabled, driver will ignore the written value
 This attribute is read-write.
 
+``boost``
+The `boost` sysfs attribute provides control over the CPU core
+performance boost, allowing users to manage the maximum frequency limitation
+of the CPU. This attribute can be used to enable or disable the boost feature
+on individual CPUs.
+
+When the boost feature is enabled, the CPU can dynamically increase its frequency
+beyond the base frequency, providing enhanced performance for demanding workloads.
+On the other hand, disabling the boost feature restricts the CPU to operate at the
+base frequency, which may be desirable in certain scenarios to prioritize power
+efficiency or manage temperature.
+
+To manipulate the `boost` attribute, users can write a value of `0` to disable the
+boost or `1` to enable it, for the respective CPU using the sysfs path
+`/sys/devices/system/cpu/cpuX/cpufreq/boost`, where `X` represents the CPU number.
+
+It is important to note that modifying the global variable
+`amd_pstate_global_params.cpb_boost` will override the individual CPU settings.
+
+
 Other performance and frequency values can be read back from
 ``/sys/devices/system/cpu/cpuX/acpi_cppc/``, see :ref:`cppc_sysfs`.
 
-- 
2.34.1


  parent reply	other threads:[~2024-05-08  7:21 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-05-08  7:21 [PATCH v10 0/7] AMD Pstate Driver Core Performance Boost Perry Yuan
2024-05-08  7:21 ` [PATCH v10 1/7] cpufreq: acpi: move MSR_K7_HWCR_CPB_DIS_BIT into msr-index.h Perry Yuan
2024-05-08  7:21 ` [PATCH v10 2/7] cpufreq: amd-pstate: initialize new core precision boost state Perry Yuan
2024-05-08  7:21 ` [PATCH v10 3/7] cpufreq: amd-pstate: implement cpb_boost sysfs entry for boost control Perry Yuan
2024-05-08  9:39   ` Oleksandr Natalenko
2024-05-08 11:42     ` Yuan, Perry
2024-05-08  7:21 ` [PATCH v10 4/7] cpufreq: amd-pstate: fix the MSR highest perf will be reset issue while cpb boost off Perry Yuan
2024-05-08  7:21 ` [PATCH v10 5/7] Documentation: cpufreq: amd-pstate: introduce the new cpu boost control method Perry Yuan
2024-05-08  7:21 ` [PATCH v10 6/7] cpufreq: amd-pstate: introduce per CPU frequency boost control Perry Yuan
2024-05-08  9:34   ` Oleksandr Natalenko
2024-05-08  9:43     ` Oleksandr Natalenko
2024-05-08 12:20       ` Yuan, Perry
2024-05-08  7:21 ` Perry Yuan [this message]
2024-05-08  8:18 ` [PATCH v10 0/7] AMD Pstate Driver Core Performance Boost Borislav Petkov
2024-05-09 16:01   ` Yuan, Perry
2024-05-09 16:12     ` Borislav Petkov
2024-05-08 15:11 ` Oleksandr Natalenko
2024-05-08 19:13   ` Oleksandr Natalenko
2024-05-08 19:21     ` Oleksandr Natalenko
2024-05-08 21:31       ` Oleksandr Natalenko
2024-05-08 22:13         ` Mario Limonciello
2024-05-09 12:01           ` Oleksandr Natalenko
2024-05-09 16:03             ` Yuan, Perry

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