From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: [PATCH v1 04/47] pci: add pci_ioremap_wc_bar() Date: Wed, 25 Mar 2015 16:03:46 -0400 Message-ID: <20150325200346.GO25884__46023.2783844278$1427313960$gmane$org@l.oracle.com> References: <1426893517-2511-1-git-send-email-mcgrof@do-not-panic.com> <1426893517-2511-5-git-send-email-mcgrof@do-not-panic.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YarXC-0007EN-Q1 for xen-devel@lists.xenproject.org; Wed, 25 Mar 2015 20:04:15 +0000 Content-Disposition: inline In-Reply-To: <1426893517-2511-5-git-send-email-mcgrof@do-not-panic.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: "Luis R. Rodriguez" Cc: jgross@suse.com, linux-fbdev@vger.kernel.org, x86@kernel.org, suresh.b.siddha@intel.com, Antonino Daplas , Daniel Vetter , "Luis R. Rodriguez" , venkatesh.pallipadi@intel.com, linux-kernel@vger.kernel.org, luto@amacapital.net, xen-devel@lists.xenproject.org, mingo@redhat.com, Tomi Valkeinen , JBeulich@suse.com, hpa@zytor.com, airlied@redhat.com, tglx@linutronix.de, bp@suse.de, Jean-Christophe Plagniol-Villard , Ingo Molnar List-Id: xen-devel@lists.xenproject.org On Fri, Mar 20, 2015 at 04:17:54PM -0700, Luis R. Rodriguez wrote: > From: "Luis R. Rodriguez" > > This lets drivers take advanate of PAT when available. This s/advanate/advantage/ > should help with the transition of converting video drivers over > to ioremap_wc() to help with the goal of eventually using > _PAGE_CACHE_UC over _PAGE_CACHE_UC_MINUS on x86 on > ioremap_nocache() (de33c442e) Please mention the title of the patch too: "x86 PAT: fix performance drop for glx, use UC minus for ioremap(), ioremap_nocache() and pci_mmap_page_range()" > > Cc: Suresh Siddha > Cc: Venkatesh Pallipadi > Cc: Ingo Molnar > Cc: Thomas Gleixner > Cc: Juergen Gross > Cc: Daniel Vetter > Cc: Andy Lutomirski > Cc: Dave Airlie > Cc: Antonino Daplas > Cc: Jean-Christophe Plagniol-Villard > Cc: Tomi Valkeinen > Cc: linux-fbdev@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Signed-off-by: Luis R. Rodriguez > --- > drivers/pci/pci.c | 14 ++++++++++++++ > include/linux/pci.h | 1 + > 2 files changed, 15 insertions(+) > > diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c > index 81f06e8..6afd507 100644 > --- a/drivers/pci/pci.c > +++ b/drivers/pci/pci.c > @@ -137,6 +137,20 @@ void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar) > pci_resource_len(pdev, bar)); > } > EXPORT_SYMBOL_GPL(pci_ioremap_bar); > + > +void __iomem *pci_ioremap_wc_bar(struct pci_dev *pdev, int bar) > +{ > + /* > + * Make sure the BAR is actually a memory resource, not an IO resource > + */ > + if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) { > + WARN_ON(1); Would it be better to use dev_warn ? That way you can see which BDF it is? Thought WARN will give a nice stack-trace that should easily point to the driver so perhaps not.. Either way - up to you. > + return NULL; > + } > + return ioremap_wc(pci_resource_start(pdev, bar), > + pci_resource_len(pdev, bar)); > +} > +EXPORT_SYMBOL_GPL(pci_ioremap_wc_bar); > #endif > > #define PCI_FIND_CAP_TTL 48 > diff --git a/include/linux/pci.h b/include/linux/pci.h > index 211e9da..c235b09 100644 > --- a/include/linux/pci.h > +++ b/include/linux/pci.h > @@ -1667,6 +1667,7 @@ static inline void pci_mmcfg_late_init(void) { } > int pci_ext_cfg_avail(void); > > void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar); > +void __iomem *pci_ioremap_wc_bar(struct pci_dev *pdev, int bar); > > #ifdef CONFIG_PCI_IOV > int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn); > -- > 2.3.2.209.gd67f9d5.dirty > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xen.org > http://lists.xen.org/xen-devel