From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Stephen M. Cameron" Subject: [PATCH 03/11] hpsa: add 5 second delay after doorbell reset Date: Thu, 07 Nov 2013 10:45:40 -0600 Message-ID: <20131107164540.3504.61950.stgit@beardog.cce.hp.com> References: <20131107164258.3504.5892.stgit@beardog.cce.hp.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: Received: from g4t0015.houston.hp.com ([15.201.24.18]:26967 "EHLO g4t0015.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753282Ab3KGQpk (ORCPT ); Thu, 7 Nov 2013 11:45:40 -0500 In-Reply-To: <20131107164258.3504.5892.stgit@beardog.cce.hp.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: james.bottomley@hansenpartnership.com Cc: stephenmcameron@gmail.com, mikem@beardog.cce.hp.com, thenzl@redhat.com, linux-scsi@vger.kernel.org, scott.teel@hp.com From: Stephen M. Cameron The hardware guys tell us that after initiating a software reset via the doorbell register we need to wait 5 seconds before attempting to talk to the board *at all*. This means that we cannot watch the board to verify it transitions from "ready" to to "not ready" then back "ready", since this transition will most likely happen during those 5 seconds (though we can still verify the reset happens by watching the "driver version" field get cleared.) Signed-off-by: Stephen M. Cameron --- drivers/scsi/hpsa.c | 32 +++++++++++++++++++++++--------- 1 files changed, 23 insertions(+), 9 deletions(-) diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c index 20fc598..fff5fd3 100644 --- a/drivers/scsi/hpsa.c +++ b/drivers/scsi/hpsa.c @@ -3781,6 +3781,13 @@ static int hpsa_controller_hard_reset(struct pci_dev *pdev, */ dev_info(&pdev->dev, "using doorbell to reset controller\n"); writel(use_doorbell, vaddr + SA5_DOORBELL); + + /* PMC hardware guys tell us we need a 5 second delay after + * doorbell reset and before any attempt to talk to the board + * at all to ensure that this actually works and doesn't fall + * over in some weird corner cases. + */ + msleep(5000); } else { /* Try to do it the PCI power state way */ /* Quoting from the Open CISS Specification: "The Power @@ -3977,15 +3984,22 @@ static int hpsa_kdump_hard_reset_controller(struct pci_dev *pdev) need a little pause here */ msleep(HPSA_POST_RESET_PAUSE_MSECS); - /* Wait for board to become not ready, then ready. */ - dev_info(&pdev->dev, "Waiting for board to reset.\n"); - rc = hpsa_wait_for_board_state(pdev, vaddr, BOARD_NOT_READY); - if (rc) { - dev_warn(&pdev->dev, - "failed waiting for board to reset." - " Will try soft reset.\n"); - rc = -ENOTSUPP; /* Not expected, but try soft reset later */ - goto unmap_cfgtable; + if (!use_doorbell) { + /* Wait for board to become not ready, then ready. + * (if we used the doorbell, then we already waited 5 secs + * so the "not ready" state is already gone by so we + * won't catch it.) + */ + dev_info(&pdev->dev, "Waiting for board to reset.\n"); + rc = hpsa_wait_for_board_state(pdev, vaddr, BOARD_NOT_READY); + if (rc) { + dev_warn(&pdev->dev, + "failed waiting for board to reset." + " Will try soft reset.\n"); + /* Not expected, but try soft reset later */ + rc = -ENOTSUPP; + goto unmap_cfgtable; + } } rc = hpsa_wait_for_board_state(pdev, vaddr, BOARD_READY); if (rc) {