From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e28smtp02.in.ibm.com (e28smtp02.in.ibm.com [122.248.162.2]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id B35CA1A04CC for ; Sun, 17 Aug 2014 13:02:46 +1000 (EST) Received: from /spool/local by e28smtp02.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Sun, 17 Aug 2014 08:32:44 +0530 Received: from d28relay04.in.ibm.com (d28relay04.in.ibm.com [9.184.220.61]) by d28dlp01.in.ibm.com (Postfix) with ESMTP id 81AE7E0017 for ; Sun, 17 Aug 2014 08:34:45 +0530 (IST) Received: from d28av01.in.ibm.com (d28av01.in.ibm.com [9.184.220.63]) by d28relay04.in.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id s7H334Ru49807394 for ; Sun, 17 Aug 2014 08:33:05 +0530 Received: from d28av01.in.ibm.com (localhost [127.0.0.1]) by d28av01.in.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id s7H32fxw007229 for ; Sun, 17 Aug 2014 08:32:42 +0530 From: Gavin Shan To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH 5/5] powerpc/eeh: Clear frozen state on passing device Date: Sun, 17 Aug 2014 13:02:29 +1000 Message-Id: <1408244549-10221-6-git-send-email-gwshan@linux.vnet.ibm.com> In-Reply-To: <1408244549-10221-1-git-send-email-gwshan@linux.vnet.ibm.com> References: <1408244549-10221-1-git-send-email-gwshan@linux.vnet.ibm.com> Cc: Gavin Shan List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , When passing through device, its PE might have been put into frozen state. One obvious example would be: the passed PE is forced to be offline because of hitting maximal allowed EEH errors in userland. In that case, the frozen state won't be cleared and then the PE is returned back to host, which might not have chance detecting and recovering from it. The patch adds more check when passing through device and clear the PE frozen state if necessary. Signed-off-by: Gavin Shan --- arch/powerpc/kernel/eeh.c | 32 +++++++++++++++++++++++++++++++- 1 file changed, 31 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c index db2841c..211175e 100644 --- a/arch/powerpc/kernel/eeh.c +++ b/arch/powerpc/kernel/eeh.c @@ -1150,6 +1150,8 @@ void eeh_remove_device(struct pci_dev *dev) int eeh_dev_open(struct pci_dev *pdev) { struct eeh_dev *edev; + int flag = (EEH_STATE_MMIO_ACTIVE | EEH_STATE_DMA_ACTIVE); + int ret = -ENODEV; mutex_lock(&eeh_dev_mutex); @@ -1162,6 +1164,34 @@ int eeh_dev_open(struct pci_dev *pdev) if (!edev || !edev->pe) goto out; + /* + * The PE might have been put into frozen state, but we + * didn't detect that yet. The passed through PCI devices + * in frozen PE won't work properly. Clear the frozen state + * in advance. + */ + ret = eeh_ops->get_state(edev->pe, NULL); + if (ret > 0 && ret != EEH_STATE_NOT_SUPPORT && + (ret & flag) != flag) { + ret = eeh_ops->set_option(edev->pe, EEH_OPT_THAW_MMIO); + if (ret) { + pr_warn("%s: Failure %d enabling MMIO " + "for PHB#%x-PE#%x\n", + __func__, ret, edev->phb->global_number, + edev->pe->addr); + goto out; + } + + ret = eeh_ops->set_option(edev->pe, EEH_OPT_THAW_DMA); + if (ret) { + pr_warn("%s: Failure %d enabling DMA " + "for PHB#%x-PE#%x\n", + __func__, ret, edev->phb->global_number, + edev->pe->addr); + goto out; + } + } + /* Increase PE's pass through count */ atomic_inc(&edev->pe->pass_dev_cnt); mutex_unlock(&eeh_dev_mutex); @@ -1169,7 +1199,7 @@ int eeh_dev_open(struct pci_dev *pdev) return 0; out: mutex_unlock(&eeh_dev_mutex); - return -ENODEV; + return ret; } EXPORT_SYMBOL_GPL(eeh_dev_open); -- 1.8.3.2