Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757266AbZLUUsi (ORCPT ); Mon, 21 Dec 2009 15:48:38 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757250AbZLUUsf (ORCPT ); Mon, 21 Dec 2009 15:48:35 -0500 Received: from hera.kernel.org ([140.211.167.34]:37488 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757237AbZLUUse (ORCPT ); Mon, 21 Dec 2009 15:48:34 -0500 Message-ID: <4B2FDEC8.9000700@kernel.org> Date: Mon, 21 Dec 2009 12:47:04 -0800 From: Yinghai Lu User-Agent: Thunderbird 2.0.0.23 (X11/20090817) MIME-Version: 1.0 To: Bjorn Helgaas CC: Jesse Barnes , Ingo Molnar , Linus Torvalds , Ivan Kokshaysky , Kenji Kaneshige , Alex Chiang , "linux-kernel@vger.kernel.org" , "linux-pci@vger.kernel.org" Subject: Re: [PATCH 0/12] pci: update pci bridge resources References: <4B2BEC0E.3050909@kernel.org> <1261352672.26429.41.camel@dc7800.home> <4B2ED29B.7060108@kernel.org> <1261370692.26429.78.camel@dc7800.home> In-Reply-To: <1261370692.26429.78.camel@dc7800.home> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3948 Lines: 109 Bjorn Helgaas wrote: > On Sun, 2009-12-20 at 17:42 -0800, Yinghai Lu wrote: >> Bjorn Helgaas wrote: >>> On Fri, 2009-12-18 at 12:54 -0800, Yinghai Lu wrote: >>>> this patche set is trying to update pci bridge BAR when that BAR is big enough. >>>> >>>> default it is disabled. >>>> >>>> could use pci=try=2 to enable it. >>> I think you mean "when the BAR is *not* big enough." And strictly >>> speaking, I think you're concerned with the bridge *window*, which isn't >>> actually a bridge BAR. >> in PCI bridge to bridge spec 1.1, page 38, 3.2.5.1 still call them bridge "Base Address Registers" >> >> so should be fine we call them Bridge BAR, >> >> and we still have device BAR... > > PCI bridges have optional BARs, described as you point out in section > 3.2.5.1. These work the same as BARs on any other PCI device, and your > patches aren't concerned with these. > > Your patch series is primarily concerned with the bridge Base & Limit > registers described in sections 3.2.5.6 (I/O), 3.2.5.8 (memory), and > 3.2.5.9 (prefetchable memory). These define the address ranges > forwarded from one bridge interface to the other. The spec doesn't have > a nice term for these ranges, but they're often referred to as "windows" > or "apertures" because they are the areas where you can "see through" > the bridge to devices on the other side. I have following patch. how to format the "bar reading" ? [PATCH] pci: reject mmio range start from 0 on pci_bridge read that is wrong. exposed by that patch that doesn't shrink pci bridge res. Signed-off-by: Yinghai Lu --- drivers/pci/probe.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) Index: linux-2.6/drivers/pci/probe.c =================================================================== --- linux-2.6.orig/drivers/pci/probe.c +++ linux-2.6/drivers/pci/probe.c @@ -316,13 +316,17 @@ void __devinit pci_read_bridge_bases(str limit |= (io_limit_hi << 16); } - if (base <= limit) { + if (base <= limit && base) { res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO; if (!res->start) res->start = base; if (!res->end) res->end = limit + 0xfff; dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res); + } else { + dev_printk(KERN_DEBUG, &dev->dev, + " bridge window [io %04lx - %04lx] bar reading\n", + base, limit); } res = child->resource[1]; @@ -330,11 +334,15 @@ void __devinit pci_read_bridge_bases(str pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo); base = (mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16; limit = (mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16; - if (base <= limit) { + if (base <= limit && base) { res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM; res->start = base; res->end = limit + 0xfffff; dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res); + } else { + dev_printk(KERN_DEBUG, &dev->dev, + " bridge window [mem 0x%08lx - 0x%08lx] bar reading\n", + base, limit + 0xfffff); } res = child->resource[2]; @@ -366,7 +374,7 @@ void __devinit pci_read_bridge_bases(str #endif } } - if (base <= limit) { + if (base <= limit && base) { res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) | IORESOURCE_MEM | IORESOURCE_PREFETCH; if (res->flags & PCI_PREF_RANGE_TYPE_64) @@ -374,6 +382,10 @@ void __devinit pci_read_bridge_bases(str res->start = base; res->end = limit + 0xfffff; dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res); + } else { + dev_printk(KERN_DEBUG, &dev->dev, + " bridge window [mem 0x%016lx - %016lx pref] bar reading\n", + base, limit + 0xfffff); } } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/