From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f175.google.com ([209.85.223.175]:33673 "EHLO mail-io0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750814AbbG2UV7 (ORCPT ); Wed, 29 Jul 2015 16:21:59 -0400 Received: by ioii16 with SMTP id i16so33412581ioi.0 for ; Wed, 29 Jul 2015 13:21:58 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <55B93507.6070101@roeck-us.net> References: <1436292680-25111-1-git-send-email-linux@roeck-us.net> <20150729160903.GD31170@google.com> <55B92DA5.4030409@roeck-us.net> <55B93507.6070101@roeck-us.net> Date: Wed, 29 Jul 2015 13:21:58 -0700 Message-ID: Subject: Re: [RFC PATCH v2] PCI: Only enable IO window if supported From: Yinghai Lu To: Guenter Roeck Cc: Bjorn Helgaas , "linux-pci@vger.kernel.org" , Lorenzo Pieralisi Content-Type: text/plain; charset=UTF-8 Sender: linux-pci-owner@vger.kernel.org List-ID: On Wed, Jul 29, 2015 at 1:18 PM, Guenter Roeck wrote: > On 07/29/2015 12:53 PM, Yinghai Lu wrote: >> >> On Wed, Jul 29, 2015 at 12:46 PM, Guenter Roeck >> wrote: >>> >>> On 07/29/2015 12:30 PM, Yinghai Lu wrote: >>> >>>> >>>> so PCI_BUS_FLAGS_SUPPORTS_IO will never get set. >>>> >>> >>> excellent catch. Unfortunately, I don't know how to make it >>> work with the reversed flag. The idea here was that the flag >>> propagates from parent to child. This makes sense for an >>> "it doesn't work" flag to be inherited from the child, >>> but not for an "it works" flag. >>> >> >> also would be better if we can add has_ioport in hostbridge instead. >> like has_mem64 in https://patchwork.ozlabs.org/patch/500926/ >> and use >> >> to_pci_host_bridge(bus->bridge)->has_ioport >> >> to replace pci_root_has_io_resource() >> > > Is there a function to get the root bus ? Otherwise I still need to > find the root bus first. host-bridge and rootbus is one to one mapping. drivers/pci/host-bridge.c has related function. Yinghai