From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e7.ny.us.ibm.com (e7.ny.us.ibm.com [32.97.182.137]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e7.ny.us.ibm.com", Issuer "GeoTrust SSL CA" (not verified)) by ozlabs.org (Postfix) with ESMTPS id 5FB862C00C8 for ; Fri, 11 Oct 2013 17:17:08 +1100 (EST) Received: from /spool/local by e7.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 11 Oct 2013 02:17:05 -0400 Received: from b01cxnp22034.gho.pok.ibm.com (b01cxnp22034.gho.pok.ibm.com [9.57.198.24]) by d01dlp02.pok.ibm.com (Postfix) with ESMTP id 246316E8040 for ; Fri, 11 Oct 2013 02:17:02 -0400 (EDT) Received: from d01av01.pok.ibm.com (d01av01.pok.ibm.com [9.56.224.215]) by b01cxnp22034.gho.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r9B6H3Fs55312412 for ; Fri, 11 Oct 2013 06:17:03 GMT Received: from d01av01.pok.ibm.com (loopback [127.0.0.1]) by d01av01.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r9B6H1E0001605 for ; Fri, 11 Oct 2013 02:17:02 -0400 Date: Fri, 11 Oct 2013 14:16:54 +0800 From: Gavin Shan To: Benjamin Herrenschmidt Subject: Re: [PATCH v2 3/6] powerpc/pci: use pci_is_pcie() to simplify code Message-ID: <20131011061654.GA561@shangw.(null)> References: <1378367730-25996-1-git-send-email-wangyijing@huawei.com> <1378367730-25996-3-git-send-email-wangyijing@huawei.com> <20130906203035.GA27940@google.com> <1381470596.5630.61.camel@pasglop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1381470596.5630.61.camel@pasglop> Cc: Gavin Shan , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, "James E.J. Bottomley" , Yijing Wang , Paul Mackerras , Hanjun Guo , Bjorn Helgaas , linuxppc-dev@lists.ozlabs.org Reply-To: Gavin Shan List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, Oct 11, 2013 at 04:49:56PM +1100, Benjamin Herrenschmidt wrote: >On Fri, 2013-09-06 at 14:30 -0600, Bjorn Helgaas wrote: >> On Thu, Sep 05, 2013 at 03:55:27PM +0800, Yijing Wang wrote: >> > Use pci_is_pcie() to simplify code. >> > >> > Acked-by: Kumar Gala >> > Reviewed-by: Gavin Shan >> > Signed-off-by: Yijing Wang >> > Cc: Gavin Shan >> > Cc: Benjamin Herrenschmidt >> > Cc: Paul Mackerras >> > Cc: linuxppc-dev@lists.ozlabs.org >> > Cc: linux-kernel@vger.kernel.org >> > --- >> > arch/powerpc/kernel/eeh.c | 3 +-- >> > arch/powerpc/sysdev/fsl_pci.c | 2 +- >> > 2 files changed, 2 insertions(+), 3 deletions(-) >> >> Ben, Paul, this has no dependencies on anything new to PCI or any >> other patches in this series, so you can take it through the POWERPC >> tree. If you don't want to do that, let me know and I can take it. >> >> If you want it: >> >> Acked-by: Bjorn Helgaas > >It's also quite broken :-) > >See below: > >> > diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c >> > index 55593ee..6ebbe54 100644 >> > --- a/arch/powerpc/kernel/eeh.c >> > +++ b/arch/powerpc/kernel/eeh.c >> > @@ -189,8 +189,7 @@ static size_t eeh_gather_pci_data(struct eeh_dev *edev, char * buf, size_t len) >> > } >> > >> > /* If PCI-E capable, dump PCI-E cap 10, and the AER */ >> > - cap = pci_find_capability(dev, PCI_CAP_ID_EXP); >> > - if (cap) { >> > + if (pci_is_pcie(dev)) { >> > n += scnprintf(buf+n, len-n, "pci-e cap10:\n"); >> > printk(KERN_WARNING >> > "EEH: PCI-E capabilities and status follow:\n"); > >So we remove reading of "cap", but slightly further down the code does: > > for (i=0; i<=8; i++) { > eeh_ops->read_config(dn, cap+4*i, 4, &cfg); > n += scnprintf(buf+n, len-n, "%02x:%x\n", 4*i, cfg); > printk(KERN_WARNING "EEH: PCI-E %02x: %08x\n", i, cfg); > } > >Which actually *uses* the value of "cap" ... oops :-) > It's my fault and I should have looked into the changes more closely. How about changing it like this: cap = pci_is_pcie(dev) ? pci_pcie_cap(dev) : pci_find_capability(dev, PCI_CAP_ID_EXP); if (cap) { ... } It would save some PCI-CFG access cycles for most cases :-) >> > diff --git a/arch/powerpc/sysdev/fsl_pci.c b/arch/powerpc/sysdev/fsl_pci.c >> > index 46ac1dd..5402a1d 100644 >> > --- a/arch/powerpc/sysdev/fsl_pci.c >> > +++ b/arch/powerpc/sysdev/fsl_pci.c >> > @@ -41,7 +41,7 @@ static void quirk_fsl_pcie_header(struct pci_dev *dev) >> > u8 hdr_type; >> > >> > /* if we aren't a PCIe don't bother */ >> > - if (!pci_find_capability(dev, PCI_CAP_ID_EXP)) >> > + if (!pci_is_pcie(dev)) >> > return; >> > >> > /* if we aren't in host mode don't bother */ Thanks, Gavin