From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org ([63.228.1.57]:45162 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752030Ab2LEHSS (ORCPT ); Wed, 5 Dec 2012 02:18:18 -0500 Message-ID: <1354691878.2351.2.camel@pasglop> Subject: Re: [linuxppc-release][PATCH] powerpc/pci-hotplug: fix init issue of rescanned pci device From: Benjamin Herrenschmidt To: Yuanquan Chen Cc: linuxppc-dev@lists.ozlabs.org, galak@kernel.crashing.org, r61911@freescale.com, linux-pci@vger.kernel.org, Bjorn Helgaas Date: Wed, 05 Dec 2012 18:17:58 +1100 In-Reply-To: <1354674717-14426-1-git-send-email-B41889@freescale.com> References: <1354674717-14426-1-git-send-email-B41889@freescale.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org List-ID: On Wed, 2012-12-05 at 10:31 +0800, Yuanquan Chen wrote: > On powerpc arch, some fixup work of PCI/PCI-e device is just done during the > first scan at booting time. For the PCI/PCI-e device rescanned after linux OS > booting up, the fixup work won't be done, which leads to dma_set_mask error or > irq related issue in rescanned PCI/PCI-e device's driver. So, it does the same > fixup work for the rescanned device to avoid this issue. Hrm, the patch is a bit gross. First the code shouldn't be copy/pasted that way but factored out. I'm surprised also that is_added is false when pcibios_enable_device() gets called ... that looks strange to me. At what point is that enable happening in the hotplug sequence ? How do you trigger the rescan anyway ? I think the problem needs to be solve at a higher level, I'm adding linux-pci & Bjorn to the CC list. Cheers, Ben. > Signed-off-by: Yuanquan Chen > --- > arch/powerpc/kernel/pci-common.c | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > > diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c > index 7f94f76..f0fb070 100644 > --- a/arch/powerpc/kernel/pci-common.c > +++ b/arch/powerpc/kernel/pci-common.c > @@ -1496,6 +1496,26 @@ int pcibios_enable_device(struct pci_dev *dev, int mask) > if (ppc_md.pcibios_enable_device_hook(dev)) > return -EINVAL; > > + if (!dev->is_added) { > + /* > + * Fixup NUMA node as it may not be setup yet by the generic > + * code and is needed by the DMA init > + */ > + set_dev_node(&dev->dev, pcibus_to_node(dev->bus)); > + > + /* Hook up default DMA ops */ > + set_dma_ops(&dev->dev, pci_dma_ops); > + set_dma_offset(&dev->dev, PCI_DRAM_OFFSET); > + > + /* Additional platform DMA/iommu setup */ > + if (ppc_md.pci_dma_dev_setup) > + ppc_md.pci_dma_dev_setup(dev); > + > + /* Read default IRQs and fixup if necessary */ > + pci_read_irq_line(dev); > + if (ppc_md.pci_irq_fixup) > + ppc_md.pci_irq_fixup(dev); > + } > return pci_enable_resources(dev, mask); > } > From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 23FB62C0090 for ; Wed, 5 Dec 2012 18:18:15 +1100 (EST) Message-ID: <1354691878.2351.2.camel@pasglop> Subject: Re: [linuxppc-release][PATCH] powerpc/pci-hotplug: fix init issue of rescanned pci device From: Benjamin Herrenschmidt To: Yuanquan Chen Date: Wed, 05 Dec 2012 18:17:58 +1100 In-Reply-To: <1354674717-14426-1-git-send-email-B41889@freescale.com> References: <1354674717-14426-1-git-send-email-B41889@freescale.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Cc: Bjorn Helgaas , linux-pci@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, r61911@freescale.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, 2012-12-05 at 10:31 +0800, Yuanquan Chen wrote: > On powerpc arch, some fixup work of PCI/PCI-e device is just done during the > first scan at booting time. For the PCI/PCI-e device rescanned after linux OS > booting up, the fixup work won't be done, which leads to dma_set_mask error or > irq related issue in rescanned PCI/PCI-e device's driver. So, it does the same > fixup work for the rescanned device to avoid this issue. Hrm, the patch is a bit gross. First the code shouldn't be copy/pasted that way but factored out. I'm surprised also that is_added is false when pcibios_enable_device() gets called ... that looks strange to me. At what point is that enable happening in the hotplug sequence ? How do you trigger the rescan anyway ? I think the problem needs to be solve at a higher level, I'm adding linux-pci & Bjorn to the CC list. Cheers, Ben. > Signed-off-by: Yuanquan Chen > --- > arch/powerpc/kernel/pci-common.c | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > > diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c > index 7f94f76..f0fb070 100644 > --- a/arch/powerpc/kernel/pci-common.c > +++ b/arch/powerpc/kernel/pci-common.c > @@ -1496,6 +1496,26 @@ int pcibios_enable_device(struct pci_dev *dev, int mask) > if (ppc_md.pcibios_enable_device_hook(dev)) > return -EINVAL; > > + if (!dev->is_added) { > + /* > + * Fixup NUMA node as it may not be setup yet by the generic > + * code and is needed by the DMA init > + */ > + set_dev_node(&dev->dev, pcibus_to_node(dev->bus)); > + > + /* Hook up default DMA ops */ > + set_dma_ops(&dev->dev, pci_dma_ops); > + set_dma_offset(&dev->dev, PCI_DRAM_OFFSET); > + > + /* Additional platform DMA/iommu setup */ > + if (ppc_md.pci_dma_dev_setup) > + ppc_md.pci_dma_dev_setup(dev); > + > + /* Read default IRQs and fixup if necessary */ > + pci_read_irq_line(dev); > + if (ppc_md.pci_irq_fixup) > + ppc_md.pci_irq_fixup(dev); > + } > return pci_enable_resources(dev, mask); > } >