From patchwork Mon Apr 4 15:25:04 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Rafael J. Wysocki" X-Patchwork-Id: 12800423 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6FF0AC433FE for ; Mon, 4 Apr 2022 15:25:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377227AbiDDP1N (ORCPT ); Mon, 4 Apr 2022 11:27:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44126 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241874AbiDDP1M (ORCPT ); Mon, 4 Apr 2022 11:27:12 -0400 Received: from cloudserver094114.home.pl (cloudserver094114.home.pl [79.96.170.134]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8602E193EA; Mon, 4 Apr 2022 08:25:15 -0700 (PDT) Received: from localhost (127.0.0.1) (HELO v370.home.net.pl) by /usr/run/smtp (/usr/run/postfix/private/idea_relay_lmtp) via UNIX with SMTP (IdeaSmtpServer 5.0.0) id 3daf4d00b9762f0a; Mon, 4 Apr 2022 17:25:13 +0200 Received: from kreacher.localnet (unknown [213.134.181.62]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by v370.home.net.pl (Postfix) with ESMTPSA id 241B166BCD2; Mon, 4 Apr 2022 17:25:13 +0200 (CEST) From: "Rafael J. Wysocki" To: Linux ACPI Cc: LKML , Linux PM , Linux PCI , Bjorn Helgaas , Mika Westerberg Subject: [PATCH v1 3/3] PCI: ACPI: PM: Power up devices in D3cold before scanning them Date: Mon, 04 Apr 2022 17:25:04 +0200 Message-ID: <5729439.MhkbZ0Pkbq@kreacher> In-Reply-To: <21439956.EfDdHjke4D@kreacher> References: <21439956.EfDdHjke4D@kreacher> MIME-Version: 1.0 X-CLIENT-IP: 213.134.181.62 X-CLIENT-HOSTNAME: 213.134.181.62 X-VADE-SPAMSTATE: clean X-VADE-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgedvvddrudejvddgkedvucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecujffqoffgrffnpdggtffipffknecuuegrihhlohhuthemucduhedtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenucfjughrpefhvffufffkjghfggfgtgesthfuredttddtjeenucfhrhhomhepfdftrghfrggvlhculfdrucghhihsohgtkhhifdcuoehrjhifsehrjhifhihsohgtkhhirdhnvghtqeenucggtffrrghtthgvrhhnpedvjeelgffhiedukedtleekkedvudfggefhgfegjefgueekjeelvefggfdvledutdenucfkphepvddufedrudefgedrudekuddriedvnecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehinhgvthepvddufedrudefgedrudekuddriedvpdhhvghlohepkhhrvggrtghhvghrrdhlohgtrghlnhgvthdpmhgrihhlfhhrohhmpedftfgrfhgrvghlucflrdcuhgihshhotghkihdfuceorhhjfiesrhhjfiihshhotghkihdrnhgvtheqpdhnsggprhgtphhtthhopeeipdhrtghpthhtoheplhhinhhugidqrggtphhisehvghgvrhdrkhgvrhhnvghlrdhorhhgpdhrtghpthhtoheplhhinhhugidqkhgvrhhnvghlsehvghgvrhdrkhgvrhhnvghlrdhorhhgpdhrtghpthhtoheplhhinhhugidqphhmsehvghgvrhdrkhgvrhhnvghlrdhorhhgpdhrtghpthhtoheplhhinhhugidqphgtihesvhhgvghrrdhkvghrnhgvlhdrohhrghdprhgt phhtthhopehhvghlghgrrghssehkvghrnhgvlhdrohhrghdprhgtphhtthhopehmihhkrgdrfigvshhtvghrsggvrhhgsehlihhnuhigrdhinhhtvghlrdgtohhm X-DCC--Metrics: v370.home.net.pl 1024; Body=6 Fuz1=6 Fuz2=6 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org From: Rafael J. Wysocki The initial configuration of ACPI power resources on some systems implies that some PCI devices on them are initially in D3cold. In some cases, especially for PCIe Root Ports, this is a "logical" D3cold, meaning that the configuration space of the device is accessible, but some of its functionality may be missing, but it very well may be real D3cold, in which case the device will not be accessible at all. However, the PCI bus type driver will need to access its configuration space in order to enumerate it. To prevent possible device enumeration failures that may ensue as a result of ACPI power resources being initially in the "off" state, power up all children of the host bridge ACPI device object that hold valid _ADR objects (which indicates that they will be enumerated by the PCI bus type driver) and do that to all children of the ACPI device objects corresponding to PCI bridges (including PCIe ports). Signed-off-by: Rafael J. Wysocki Acked-by: Bjorn Helgaas --- drivers/acpi/pci_root.c | 2 ++ drivers/pci/pci-acpi.c | 3 +++ 2 files changed, 5 insertions(+) Index: linux-pm/drivers/acpi/pci_root.c =================================================================== --- linux-pm.orig/drivers/acpi/pci_root.c +++ linux-pm/drivers/acpi/pci_root.c @@ -927,6 +927,8 @@ struct pci_bus *acpi_pci_root_create(str host_bridge->preserve_config = 1; ACPI_FREE(obj); + acpi_dev_power_up_children_with_adr(device); + pci_scan_child_bus(bus); pci_set_host_bridge_release(host_bridge, acpi_pci_root_release_info, info); Index: linux-pm/drivers/pci/pci-acpi.c =================================================================== --- linux-pm.orig/drivers/pci/pci-acpi.c +++ linux-pm/drivers/pci/pci-acpi.c @@ -1374,6 +1374,9 @@ void pci_acpi_setup(struct device *dev, acpi_pci_wakeup(pci_dev, false); acpi_device_power_add_dependent(adev, dev); + + if (pci_is_bridge(pci_dev)) + acpi_dev_power_up_children_with_adr(adev); } void pci_acpi_cleanup(struct device *dev, struct acpi_device *adev)