From nobody Wed Apr 1 10:05:09 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id ECAFD44B69C; Tue, 31 Mar 2026 19:59:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774987158; cv=none; b=M7UqhyR+VgYO3cSehmjPUez67ghF1C0FQMCugfjvPRillcVXGvMxx454hzDmehjFfu21HwLo/jaoBj9ugRB+iEpdtKDrbk+xFnB2uGW+ET/dvgqMox9xbdO1mPvCrKgKekqiU0gbS4sg0+NeOklDviP/Jz7eb8D9OU1Wwi5+Srw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774987158; c=relaxed/simple; bh=AFcKf9FuptOE5/WZiSx/Mj+LSnpMrnu6CfHwBxPpOR0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ctv9UaV4Jql99+gcDG5bL469oIjzM+2srOjOE2/He5OwxmbZQj22zoTWxXcaol8qMGt+SECA/cAhi2COtXw7slnOYSWaFnJMBlH3DRywivANQIvpi0K1XLHgoAfOwubVfKNy8eWKhG/F6XdrPhFwRRtik03xDnrZ7GsOBJ4HKTA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=odI5dzNU; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="odI5dzNU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3A69DC2BCB0; Tue, 31 Mar 2026 19:59:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774987157; bh=AFcKf9FuptOE5/WZiSx/Mj+LSnpMrnu6CfHwBxPpOR0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=odI5dzNU1oDCEge01ZXjzf7Aq6YgEhFI2ou99ObcEg66c33GDTfJouQ0+Mo4sT9iE /tUkKv4DKB3udwzO5TIhQp3xBv4xKqXSuhFm49P/XJIkeLOxMmyfoCh+7GSPxRzsAC Fh3T8H9fMMUfK+OqmGRzZs5GggBM1QbLW0bZXz4YiqbM3WZMNrwJFLwaHssBCKiDks bbtcroEef+A0RFcB3cSp5dW2mSoUPSWTWeOEX0lR5KmrkjsQndT+4yozQwvDjBCJIl k/Q15vbtMYtxI9u+gjiopbWPa3PFiA8objLV4SjC74XNnpwwdEwPayEX9njONbMLrj F2c6p5iiRtHzA== From: "Mario Limonciello (AMD)" To: "Gautham R . Shenoy" Cc: Perry Yuan , linux-kernel@vger.kernel.org (open list:X86 ARCHITECTURE (32-BIT AND 64-BIT)), linux-pm@vger.kernel.org (open list:CPU FREQUENCY SCALING FRAMEWORK), "Mario Limonciello (AMD)" Subject: [PATCH v7 2/5] cpufreq/amd-pstate: add kernel command line to override dynamic epp Date: Tue, 31 Mar 2026 14:59:04 -0500 Message-ID: <20260331195907.2557193-3-superm1@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260331195907.2557193-1-superm1@kernel.org> References: <20260331195907.2557193-1-superm1@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add `amd_dynamic_epp=3Denable` and `amd_dynamic_epp=3Ddisable` to override the kernel configuration option `CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP` locally. Signed-off-by: Mario Limonciello (AMD) Reviewed-by: Gautham R. Shenoy --- Documentation/admin-guide/kernel-parameters.txt | 7 +++++++ Documentation/admin-guide/pm/amd-pstate.rst | 7 +++++++ drivers/cpufreq/amd-pstate.c | 11 +++++++++++ 3 files changed, 25 insertions(+) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentatio= n/admin-guide/kernel-parameters.txt index 03a550630644f..9552819051cd8 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -493,6 +493,13 @@ Kernel parameters disable Disable amd-pstate preferred core. =20 + amd_dynamic_epp=3D + [X86] + disable + Disable amd-pstate dynamic EPP. + enable + Enable amd-pstate dynamic EPP. + amijoy.map=3D [HW,JOY] Amiga joystick support Map of devices attached to JOY0DAT and JOY1DAT Format: , diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/ad= min-guide/pm/amd-pstate.rst index bb1341763882b..01e6ab10f996e 100644 --- a/Documentation/admin-guide/pm/amd-pstate.rst +++ b/Documentation/admin-guide/pm/amd-pstate.rst @@ -474,6 +474,13 @@ For systems that support ``amd-pstate`` preferred core= , the core rankings will always be advertised by the platform. But OS can choose to ignore that via= the kernel parameter ``amd_prefcore=3Ddisable``. =20 +``amd_dynamic_epp`` + +When AMD pstate is in auto mode, dynamic EPP will control whether the kern= el +autonomously changes the EPP mode. The default is configured by +``CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP`` but can be explicitly enabled with +``amd_dynamic_epp=3Denable`` or disabled with ``amd_dynamic_epp=3Ddisable`= `. + User Space Interface in ``sysfs`` - General =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =20 diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index d3c8eaab88286..de22d9bd28cc6 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -2230,8 +2230,19 @@ static int __init amd_prefcore_param(char *str) return 0; } =20 +static int __init amd_dynamic_epp_param(char *str) +{ + if (!strcmp(str, "disable")) + dynamic_epp =3D false; + if (!strcmp(str, "enable")) + dynamic_epp =3D true; + + return 0; +} + early_param("amd_pstate", amd_pstate_param); early_param("amd_prefcore", amd_prefcore_param); +early_param("amd_dynamic_epp", amd_dynamic_epp_param); =20 MODULE_AUTHOR("Huang Rui "); MODULE_DESCRIPTION("AMD Processor P-state Frequency Driver"); --=20 2.43.0