From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e23smtp08.au.ibm.com (e23smtp08.au.ibm.com [202.81.31.141]) (using TLSv1 with cipher CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 473B51A0144 for ; Mon, 11 May 2015 16:48:21 +1000 (AEST) Received: from /spool/local by e23smtp08.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 11 May 2015 16:48:19 +1000 Received: from d23relay10.au.ibm.com (d23relay10.au.ibm.com [9.190.26.77]) by d23dlp02.au.ibm.com (Postfix) with ESMTP id A618B2BB0052 for ; Mon, 11 May 2015 16:48:17 +1000 (EST) Received: from d23av02.au.ibm.com (d23av02.au.ibm.com [9.190.235.138]) by d23relay10.au.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t4B6m9ea41877700 for ; Mon, 11 May 2015 16:48:17 +1000 Received: from d23av02.au.ibm.com (localhost [127.0.0.1]) by d23av02.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id t4B6livv014285 for ; Mon, 11 May 2015 16:47:45 +1000 Date: Mon, 11 May 2015 16:47:20 +1000 From: Gavin Shan To: Alexey Kardashevskiy Subject: Re: [PATCH v4 10/21] powerpc/powernv: Fundamental reset for PCI bus reset Message-ID: <20150511064720.GB8241@gwshan> Reply-To: Gavin Shan References: <1430460188-31343-1-git-send-email-gwshan@linux.vnet.ibm.com> <1430460188-31343-11-git-send-email-gwshan@linux.vnet.ibm.com> <554E15C2.40506@ozlabs.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <554E15C2.40506@ozlabs.ru> Cc: bhelgaas@google.com, linux-pci@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Gavin Shan List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Sun, May 10, 2015 at 12:12:18AM +1000, Alexey Kardashevskiy wrote: >On 05/01/2015 04:02 PM, Gavin Shan wrote: >>Function pnv_pci_reset_secondary_bus() is used to reset specified >>PCI bus, which is leaded by root complex or PCI bridge. That means >>the function shouldn't be called on PCI root bus and the patch >>removes the logic for that case. >> >>Also, some adapters beneath the indicated PCI bus may require >>fundamental reset in order to successfully reload their firmwares >>after the reset. The patch translates hot reset to fundamental reset >>for that case. >> >>Signed-off-by: Gavin Shan >>--- >> arch/powerpc/platforms/powernv/eeh-powernv.c | 35 +++++++++++++++++++++------- >> 1 file changed, 26 insertions(+), 9 deletions(-) >> >>diff --git a/arch/powerpc/platforms/powernv/eeh-powernv.c b/arch/powerpc/platforms/powernv/eeh-powernv.c >>index 3c01095..58e4dcf 100644 >>--- a/arch/powerpc/platforms/powernv/eeh-powernv.c >>+++ b/arch/powerpc/platforms/powernv/eeh-powernv.c >>@@ -888,18 +888,35 @@ static int pnv_eeh_bridge_reset(struct pci_dev *dev, int option) >> return (rc == OPAL_SUCCESS) ? 0 : -EIO; >> } >> >>-void pnv_pci_reset_secondary_bus(struct pci_dev *dev) > > >Why changing dev to pdev? Keeping "dev" could make the patch simpler. > In the early stage when I wrote the EEH code, I had "dev" to refer PCI device, which isn't precisely enough. Actually, "dev" means "struct device" while "pdev" stands for "struct pci_dev". That's why I changed it. >>+static int pnv_pci_dev_reset_type(struct pci_dev *pdev, void *data) >> { >>- struct pci_controller *hose; >>+ int *freset = data; >> >>- if (pci_is_root_bus(dev->bus)) { >>- hose = pci_bus_to_host(dev->bus); >>- pnv_eeh_phb_reset(hose, EEH_RESET_HOT); >>- pnv_eeh_phb_reset(hose, EEH_RESET_DEACTIVATE); >>- } else { >>- pnv_eeh_bridge_reset(dev, EEH_RESET_HOT); >>- pnv_eeh_bridge_reset(dev, EEH_RESET_DEACTIVATE); >>+ /* >>+ * Stop the iteration immediately if there is any >>+ * one PCI device requesting fundamental reset >>+ */ >>+ *freset |= pdev->needs_freset; >>+ return *freset; >>+} >>+ >>+void pnv_pci_reset_secondary_bus(struct pci_dev *pdev) >>+{ >>+ int option = EEH_RESET_HOT; >>+ int freset = 0; >>+ >>+ /* Check if there're any PCI devices asking for fundamental reset */ >>+ if (pdev->subordinate) { >>+ pci_walk_bus(pdev->subordinate, >>+ pnv_pci_dev_reset_type, >>+ &freset); >>+ if (freset) >>+ option = EEH_RESET_FUNDAMENTAL; >> } >>+ >>+ /* Issue the requested type of reset */ >>+ pnv_eeh_bridge_reset(pdev, option); >>+ pnv_eeh_bridge_reset(pdev, EEH_RESET_DEACTIVATE); >> } >> >> /** >> Thanks, Gavin