From patchwork Fri Aug 23 04:25:05 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mario Limonciello X-Patchwork-Id: 13774585 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 475827345B; Fri, 23 Aug 2024 04:25:58 +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=1724387158; cv=none; b=JJ8pk0njYPPVkqpPrhfRqd8jva9KnfI0GqeHCtQKy5sL1dp5Ab5PmFaK0p1PQ93i3K9wT1XwdsSpGW4FdA29j5+aEoqAhOweX2kBeu5FGHDGpaSroZY29beVCzyVj6zeOjnfqlc3r3Zg7ohd3f2INY5AEWDHs7sQ5C8suMlmWnQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724387158; c=relaxed/simple; bh=khgcZTdcadskw9ICjrzaNIg7PTgVIwoH2HRI4HWP9KA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=egnnglIAYb9P6Mzskge2/ATqVQPhRedodzH1NA49uyDgyYz1V5prGabm6Mkx1DaqZ4jWh5eM/RMoqaPkqr4LDbFDN3gIJXOAZcQmGVhihvoTLguwpGeBeyP3S5vCNmN5x2DQeQl4pLB4H7G7d1HBzZHdNC8WeaAQJnIdIbABRHU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=n2ucnUs7; 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="n2ucnUs7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1C074C32786; Fri, 23 Aug 2024 04:25:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1724387158; bh=khgcZTdcadskw9ICjrzaNIg7PTgVIwoH2HRI4HWP9KA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=n2ucnUs7aUD0SBaMn+cJjeszHD1Ml9yZoXuy2mgg14dfcbJEB/EO7ytzXZJ3Ko9qS Z2NlkAGES1aYrqApD+XrIV0JvZGM5vvPL1as0CEA6ZEzZ93leKUIldgBef519e9Duu 5WVgNIxviQfdRyIHqll3+/kP3JRHLEgj0uVBVgHRYK7D4V8n38flDye07XDlR9ym3k 07GA8mp1/C/cWyMnfESC7GPV4b/IiKt8oqQYHFydtwBmERRpTwvKAN1J2e9yIvmDvw rSK2t2Bvfq4Rn+EoDgVVPgQLMRahr4rjubg+ifU8QM1CpizbbpPuO51Y/gHsHX0bJH w6SKd89FhCrvA== From: Mario Limonciello To: Bjorn Helgaas , Mathias Nyman , Mika Westerberg Cc: "open list : PCI SUBSYSTEM" , open list , "open list : USB XHCI DRIVER" , Daniel Drake , Gary Li , Greg Kroah-Hartman , =?utf-8?q?Ilpo_J=C3=A4rvin?= =?utf-8?q?en?= , Mario Limonciello Subject: [PATCH v4 2/5] PCI: Check PCI_PM_CTRL instead of PCI_COMMAND in pci_dev_wait() Date: Thu, 22 Aug 2024 23:25:05 -0500 Message-ID: <20240823042508.1057791-4-superm1@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240823042508.1057791-1-superm1@kernel.org> References: <20240823042508.1057791-1-superm1@kernel.org> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Mario Limonciello A device that has gone through a reset may return a value in PCI_COMMAND but that doesn't mean it's finished transitioning to D0. On devices that support power management explicitly check PCI_PM_CTRL on everything but system resume to ensure the transition happened. Devices that don't support power management and system resume will continue to use PCI_COMMAND. Signed-off-by: Mario Limonciello --- drivers/pci/pci.c | 28 ++++++++++++++++++++-------- 1 file changed, 20 insertions(+), 8 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index e4a7f5dfe6bf4..b7717155e2fd0 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1308,21 +1308,33 @@ static int pci_dev_wait(struct pci_dev *dev, enum pci_reset_type reset_type, int * the read (except when CRS SV is enabled and the read was for the * Vendor ID; in that case it synthesizes 0x0001 data). * - * Wait for the device to return a non-CRS completion. Read the - * Command register instead of Vendor ID so we don't have to - * contend with the CRS SV value. + * Wait for the device to return a non-CRS completion. On devices + * that support PM control and on waits that aren't part of system + * resume read the PM control register to ensure the device has + * transitioned to D0. On devices that don't support PM control, + * or during system resume read the command register to instead of + * Vendor ID so we don't have to contend with the CRS SV value. */ for (;;) { - u32 id; - if (pci_dev_is_disconnected(dev)) { pci_dbg(dev, "disconnected; not waiting\n"); return -ENOTTY; } - pci_read_config_dword(dev, PCI_COMMAND, &id); - if (!PCI_POSSIBLE_ERROR(id)) - break; + if (dev->pm_cap && reset_type != PCI_DEV_WAIT_RESUME) { + u16 pmcsr; + + pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr); + if (!PCI_POSSIBLE_ERROR(pmcsr) && + (pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D0) + break; + } else { + u32 id; + + pci_read_config_dword(dev, PCI_COMMAND, &id); + if (!PCI_POSSIBLE_ERROR(id)) + break; + } if (delay > timeout) { pci_warn(dev, "not ready %dms after %s; giving up\n",