From nobody Wed Dec 17 01:09:38 2025 Received: from mail-pj1-f49.google.com (mail-pj1-f49.google.com [209.85.216.49]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3305A4AEEA for ; Fri, 19 Jul 2024 07:59:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.49 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721375967; cv=none; b=TuuKMFKU04Myl/cmE+deih+486/WYx2dItxk2bL5vA0hEmE1jTgQRKqA79lbKPemhKuRJBbF1lnyMkEs4JkyvMrZ5CIiQtoR96AqKNuRnX9qx3bvAKky1/yituJrVa1jKrIo1JyqO5DhQcQ9YU9lFAgCECb3Ad4SziH3P4zpZsA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721375967; c=relaxed/simple; bh=dG95QewEG8mN5e80OJowMbRNCEU8UUwID07dkXmIk7M=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=UuhC62Zf2Kb172Kwana0Qtpksl9/bYhyzBO4wypDTbrqkO9wHNdBEPLs7NLoqSDglZeJRVz32BFDUzrZ/jyOcShAejk5fNzgUmyYr9166hZUzF2BwwKGi0U4eE1YpdLhqINmgvZDcx734LVCvgj4qTBm243dOY4JRYM5mBEZw3k= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=endlessos.org; spf=pass smtp.mailfrom=endlessos.org; dkim=pass (2048-bit key) header.d=endlessos.org header.i=@endlessos.org header.b=XuT+Zi/c; arc=none smtp.client-ip=209.85.216.49 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=endlessos.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=endlessos.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=endlessos.org header.i=@endlessos.org header.b="XuT+Zi/c" Received: by mail-pj1-f49.google.com with SMTP id 98e67ed59e1d1-2cb63ceff6dso778566a91.1 for ; Fri, 19 Jul 2024 00:59:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=endlessos.org; s=google; t=1721375964; x=1721980764; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=VDVxrTlyCYmX4gNYVSGtw5JAwr1I2e12lJyeUPu4kzA=; b=XuT+Zi/cLpndpMZ2iySVTEU3bPXCaEJtuxNmJjnW5abmjg7fQFnMmNorS1wEUjAL8H UbEh5k2STottJzn6MxgrJgAoz2SyfGm1iZyrufPsSzvQvV+b1rAWa0Sm4hCXo07OHLyk A0uYdebLJWP7GX4+7B6iL1ngcqJd6OZZUwVKv+mRbGd6SjPvMU+18502PZ88OfwSvlcD 71ErcaUnVLRDjI8cm0Ao6Jph0z3IFRkjZ5Y/4xJKi16ng/h72ORMkXenGH0CR2UGD1Sd QRMHYW2oUwHCkKMFnVwhJ7OmNVyA5ADgQ+pQmCahkddN3s8mn1/R/wc0hL65zb4wOwqx D0AA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1721375964; x=1721980764; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=VDVxrTlyCYmX4gNYVSGtw5JAwr1I2e12lJyeUPu4kzA=; b=byCDvIYDjujMa6jwHVgx5WhHoqpT5Ka0HxcRyl63okZY/0J9+V9vCSvTOJpqxp7fvF OEl3/bG5YWSpVv4yUhZaQ2UtGyHLMtmpDiomZKrA/+KSKWUsha3/51LkrBcWnQTy2kro 1oT5KYeUMdlVJNOuJcWfEeA0y3is3Vr5eCpkb+gh6HwnWX80MqSD0jbFXHTWf+I84oFV i7bC97S9Ht6wHDk0UeGy3VSYMg9UidS4aBPUNYf9TiwVoevnGRpj5/LlR4iObM66Mgh5 bzHUtr6Hgshpb4/DKdZVcsHi4QCv8Iv/r8U+aH3+t4k40ePByu5c+CrZsiPD+AECyem5 QGUQ== X-Forwarded-Encrypted: i=1; AJvYcCUtDfUIDXW8JYhTWn9ympgt4uEJkaPhbSsQwCEyMAEYsHfn65ANWUrwy81DIodC1XVJf6uMY/HbwBDa3bnjAasWSHgjf7qA7e4HHoJU X-Gm-Message-State: AOJu0Yw8abWaZo0YXMmSLA1pG4OwU47SAqzL57cGuk/ufN7ZUp7rC0PP 0cDR+S/n8Vk+amYO89RjxpC8cw3Sn6sKwN5Z3FwFMFvBsYuiHer+kskq6a5B65U= X-Google-Smtp-Source: AGHT+IHT+6quf4rYKsrBUnn6NfLGKfmvUAKKbfARVQXy1NR/Ekq0ZjIfo2ufGSrvu2kO1esvs/I7NA== X-Received: by 2002:a17:90a:d181:b0:2c9:7fba:d890 with SMTP id 98e67ed59e1d1-2cb5294bf43mr5302138a91.43.1721375964348; Fri, 19 Jul 2024 00:59:24 -0700 (PDT) Received: from localhost.localdomain ([123.51.167.56]) by smtp.googlemail.com with ESMTPSA id 98e67ed59e1d1-2cb7750674csm2058112a91.43.2024.07.19.00.59.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 19 Jul 2024 00:59:24 -0700 (PDT) From: Jian-Hong Pan To: Bjorn Helgaas Cc: Johan Hovold , David Box , =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= , Kuppuswamy Sathyanarayanan , Mika Westerberg , Damien Le Moal , Nirmal Patel , Jonathan Derrick , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux@endlessos.org, Jian-Hong Pan , Bjorn Helgaas Subject: [PATCH v8 2/4] PCI/ASPM: Add notes about enabling PCI-PM L1SS to pci_enable_link_state(_locked) Date: Fri, 19 Jul 2024 15:57:54 +0800 Message-ID: <20240719075752.10883-3-jhp@endlessos.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240719075200.10717-2-jhp@endlessos.org> References: <20240719075200.10717-2-jhp@endlessos.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" According to "PCIe r6.0, sec 5.5.4", add note about D0 requirement in pci_enable_link_state() kernel-doc. Signed-off-by: Jian-Hong Pan Acked-by: Bjorn Helgaas Reviewed-by: Kuppuswamy Sathyanarayanan --- v3: - Fix as readable comments v4: - The same v5: - Tweak and simplify the commit message v6~8: - The same drivers/pci/pcie/aspm.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c index cee2365e54b8..bd0a8a05647e 100644 --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -1442,6 +1442,9 @@ static int __pci_enable_link_state(struct pci_dev *pd= ev, int state, bool locked) * touch the LNKCTL register. Also note that this does not enable states * disabled by pci_disable_link_state(). Return 0 or a negative errno. * + * Note: Ensure devices are in D0 before enabling PCI-PM L1 PM Substates, = per + * PCIe r6.0, sec 5.5.4. + * * @pdev: PCI device * @state: Mask of ASPM link states to enable */ @@ -1458,6 +1461,9 @@ EXPORT_SYMBOL(pci_enable_link_state); * can't touch the LNKCTL register. Also note that this does not enable st= ates * disabled by pci_disable_link_state(). Return 0 or a negative errno. * + * Note: Ensure devices are in D0 before enabling PCI-PM L1 PM Substates, = per + * PCIe r6.0, sec 5.5.4. + * * @pdev: PCI device * @state: Mask of ASPM link states to enable * --=20 2.45.2