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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>, <gautham.shenoy@amd.com>
Cc: <Xinmei.Huang@amd.com>, <Xiaojian.Du@amd.com>, <Li.Meng@amd.com>,
	<linux-pm@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: [PATCH v12 9/9] Documentation: cpufreq: amd-pstate: update doc for Per CPU boost control method
Date: Wed, 19 Jun 2024 17:16:42 +0800	[thread overview]
Message-ID: <6b705dc178d484dd4f99e6bd134bdf09ee0a879e.1718787627.git.perry.yuan@amd.com> (raw)
In-Reply-To: <cover.1718787627.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>
Reviewed-by: Mario Limonciello <mario.limonciello@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:[~2024-06-19  9:17 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-06-19  9:16 [PATCH v12 0/9] AMD Pstate Driver Core Performance Boost Perry Yuan
2024-06-19  9:16 ` [PATCH v12 1/9] cpufreq: acpi: move MSR_K7_HWCR_CPB_DIS_BIT into msr-index.h Perry Yuan
2024-06-19  9:16 ` [PATCH v12 2/9] cpufreq: simplify boolean parsing with kstrtobool in store function Perry Yuan
2024-06-21  4:30   ` Gautham R.Shenoy
2024-06-19  9:16 ` [PATCH v12 3/9] cpufreq: introduce init_boost callback to initialize boost state for pstate drivers Perry Yuan
2024-06-19 17:37   ` Mario Limonciello
2024-06-19  9:16 ` [PATCH v12 4/9] cpufreq: amd-pstate: initialize new core precision boost state Perry Yuan
2024-06-19 19:32   ` Mario Limonciello
2024-06-21  5:23   ` Gautham R.Shenoy
2024-06-19  9:16 ` [PATCH v12 5/9] cpufreq: amd-pstate: implement cpb_boost sysfs entry for boost control Perry Yuan
2024-06-19 19:39   ` Mario Limonciello
2024-06-21  5:36     ` Gautham R.Shenoy
2024-06-19  9:16 ` [PATCH v12 6/9] cpufreq: amd-pstate: Add set_boost callback for active mode Perry Yuan
2024-06-19 19:40   ` Mario Limonciello
2024-06-21  5:39   ` Gautham R.Shenoy
2024-06-21  5:54     ` Yuan, Perry
2024-06-19  9:16 ` [PATCH v12 7/9] cpufreq: amd-pstate: fix the MSR highest perf will be reset issue while cpb boost off Perry Yuan
2024-06-21  5:46   ` Gautham R.Shenoy
2024-06-21  5:56     ` Yuan, Perry
2024-06-19  9:16 ` [PATCH v12 8/9] Documentation: cpufreq: amd-pstate: introduce the new cpu boost control method Perry Yuan
2024-06-19 19:40   ` Mario Limonciello
2024-06-19  9:16 ` Perry Yuan [this message]
2024-06-19 19:45   ` [PATCH v12 9/9] Documentation: cpufreq: amd-pstate: update doc for Per CPU " Mario Limonciello
2024-06-21  6:42     ` Gautham R.Shenoy

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