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
next prev 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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