Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754904Ab3HEThx (ORCPT ); Mon, 5 Aug 2013 15:37:53 -0400 Received: from mx1.redhat.com ([209.132.183.28]:53820 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754601Ab3HEThu (ORCPT ); Mon, 5 Aug 2013 15:37:50 -0400 Subject: [PATCH v4 7/9] pci: Wake-up devices before save for reset To: bhelgaas@google.com, linux-pci@vger.kernel.org From: Alex Williamson Cc: ddutile@redhat.com, indou.takao@jp.fujitsu.com, linux-kernel@vger.kernel.org Date: Mon, 05 Aug 2013 13:37:47 -0600 Message-ID: <20130805193746.9260.8439.stgit@bling.home> In-Reply-To: <20130805193200.9260.38729.stgit@bling.home> References: <20130805193200.9260.38729.stgit@bling.home> User-Agent: StGit/0.16 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1429 Lines: 38 Devices come out of reset in D0. Restoring a device to a different post-reset state takes more smarts than our simple config space restore, which can leave devices in an inconsistent state. For example, if a device is reset in D3, but the restore doesn't successfully return the device to D3, then the actual state of the device and dev->current_state are contradictory. Put everything in D0 going into the reset, then we don't need to do anything special on the way out. Signed-off-by: Alex Williamson --- drivers/pci/pci.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 1dba7dd..b204206 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -3332,6 +3332,13 @@ static void pci_dev_unlock(struct pci_dev *dev) static void pci_dev_save_and_disable(struct pci_dev *dev) { + /* + * Wake-up device prior to save. PM registers default to D0 after + * reset and a simple register restore doesn't reliably return + * to a non-D0 state anyway. + */ + pci_set_power_state(dev, PCI_D0); + pci_save_state(dev); /* * Disable the device by clearing the Command register, except for -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/