From mboxrd@z Thu Jan 1 00:00:00 1970 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 600CA3A960A for ; Mon, 13 Jul 2026 09:32:03 +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=1783935123; cv=none; b=IIg7HAF2t/2LDsaY3sMmhIJjlgICB4Kp1vzPda7RBV+ZkQX8V0G49QRJpu7Kia7jS9BdgGN4RIyNTealyEqyRHZqXoP+RKqch6Tdi/hkX2rHcQSDc3ZxzDe4Xm4+MdHCE+5fNpWfQkuomvyvKmuTpab71voCoXknCOXgKb4mLsc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783935123; c=relaxed/simple; bh=NDHGXu4/crhHhf8f1+k5t3yB0zbq5kPedmZy00Mz4D4=; h=From:To:Subject:Date:Message-ID:In-Reply-To:References: Content-Type:MIME-Version; b=qdQaNbV98gutel0LWfB9QuqXgbJdG6rZSBm62ykcMC4RdBiIUJ3AYQuycjySDclbjyP6yA7iHm1BtaoTZFcLAbc6qVXusekCc3nR6+yJDXgu6LYE+WQnHsQ0hQm0TcB6yFLExuI2J4QjealH+iHT81Vc1OSSXylJCufnk+FiVdA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Zc+NHdoI; 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="Zc+NHdoI" Received: by smtp.kernel.org (Postfix) with ESMTPS id EFD0CC2BCFB for ; Mon, 13 Jul 2026 09:32:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1783935123; bh=NDHGXu4/crhHhf8f1+k5t3yB0zbq5kPedmZy00Mz4D4=; h=From:To:Subject:Date:In-Reply-To:References:From; b=Zc+NHdoIlThBIM1Rez49lS3FzO1nnOJoSqqqlwYcik4y08ss7IsHImVZ8qdDtIVh7 S53LmflW3iKX1hETpWn0YFhPwDNWopw8leFSjIZTe27eBJDulHdCcFvNGNkeoiiFHC ZYveoQLIkTqIwVRZuxcG5Z5JNJTAOykPMSUy0bBEy0bCc2hbAScIbJNqihw7spN96k vexibu1/YCF3CUMnqqVBvQGijFAVMUVy01LRuoccLpxnKppGDU5ZXYQDNlVEPQd+7i 2yrboPW8wvAEQTL4oQRlhaDICTUV5+t9pbNhHI7FZC4NMTlS8F4hJIp3f//Fu8lmF6 nsNwDzb+6fhXg== Received: by aws-us-west-2-korg-bugzilla-1.web.codeaurora.org (Postfix, from userid 48) id E00F0C53BBF; Mon, 13 Jul 2026 09:32:02 +0000 (UTC) From: bugzilla-daemon@kernel.org To: platform-driver-x86@vger.kernel.org Subject: [Bug 218305] Ryzen 7 7840HS gets stuck at 544MHz frequency after resuming after unplugging the power cord during sleep Date: Mon, 13 Jul 2026 09:32:02 +0000 X-Bugzilla-Reason: None X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: AssignedTo drivers_platform_x86@kernel-bugs.osdl.org X-Bugzilla-Product: Drivers X-Bugzilla-Component: Platform_x86 X-Bugzilla-Version: 2.5 X-Bugzilla-Keywords: X-Bugzilla-Severity: blocking X-Bugzilla-Who: aros@gmx.com X-Bugzilla-Status: REOPENED X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: drivers_platform_x86@kernel-bugs.osdl.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugzilla.kernel.org/ Auto-Submitted: auto-generated Precedence: bulk X-Mailing-List: platform-driver-x86@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 https://bugzilla.kernel.org/show_bug.cgi?id=3D218305 --- Comment #153 from Artem S. Tashkinov (aros@gmx.com) --- Mario, someone used Claude to dig into the issue and here's what it has to = say: --------------------------------------------------------------- **Why it works on Windows:** AMD's Windows drivers explicitly re-initialize= the SMU CPPC handshake in their resume path. The Linux `amd_pmc` and `amd-pstate` drivers do not. --- ## How an upstream provider can fix this ### Kernel fix (correct layer =E2=80=94 `amd-pstate` / `amd_pmc`) `drivers/cpufreq/amd-pstate.c` =E2=80=94 The driver needs a `.resume()` cal= lback (or a `syscore_ops.resume` hook) that re-writes the CPPC `desired_perf` register = for every online CPU. In active mode this means re-issuing the CPPC performance request that was = in effect before suspend, forcing the SMU to re-accept OS-side CPPC control. `drivers/platform/x86/amd/pmc/pmc.c` =E2=80=94 The `amd_pmc` driver orchest= rates the s2idle handshake. On the exit path (`amd_pmc_resume_handler`) it could call a notifier that l= ets `amd-pstate` re-initialize CPPC, ensuring the SMU is back under kernel control before us= er processes resume. --------------------------------------------------------------- Is this doable/plausible? --=20 You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.=