From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1752264AbcCYGuF (ORCPT <rfc822;w@1wt.eu>);
	Fri, 25 Mar 2016 02:50:05 -0400
Received: from szxga02-in.huawei.com ([119.145.14.65]:40399 "EHLO
	szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1751091AbcCYGuB (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Fri, 25 Mar 2016 02:50:01 -0400
Subject: Re: Question about PCI I/O space in ARM64
To: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
References: <56F209A9.4040304@huawei.com>
 <20160323101840.GA21390@e104818-lin.cambridge.arm.com>
 <8793380.nuVa09lFue@wuerfel> <56F35BAA.50800@huawei.com>
 <20160324175728.GC21749@red-moon>
CC: Arnd Bergmann <arnd@arndb.de>, Catalin Marinas <catalin.marinas@arm.com>,
        <linux-pci@vger.kernel.org>,
        linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
        Gabriele Paoloni <gabriele.paoloni@huawei.com>,
        Linuxarm <linuxarm@huawei.com>, <linux-kernel@vger.kernel.org>,
        Zhou Wang <wangzhou1@hisilicon.com>, <jdelvare@suse.de>,
        "xuwei (O)" <xuwei5@hisilicon.com>
From: Kefeng Wang <wangkefeng.wang@huawei.com>
Message-ID: <56F4DF80.5070707@huawei.com>
Date: Fri, 25 Mar 2016 14:49:36 +0800
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101
 Thunderbird/38.5.1
MIME-Version: 1.0
In-Reply-To: <20160324175728.GC21749@red-moon>
Content-Type: text/plain; charset="windows-1252"
Content-Transfer-Encoding: 7bit
X-Originating-IP: [10.177.19.180]
X-CFilter-Loop: Reflected
X-Mirapoint-Virus-RAPID-Raw: score=unknown(0),
	refid=str=0001.0A020204.56F4DF8B.0068,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0,
	ip=0.0.0.0,
	so=2013-06-18 04:22:30,
	dmn=2013-03-21 17:37:32
X-Mirapoint-Loop-Id: 0d7a82a601867db96fef5cc1e713c31b
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org



On 2016/3/25 1:57, Lorenzo Pieralisi wrote:
> [+ Jean]
> 
> On Thu, Mar 24, 2016 at 11:14:50AM +0800, Kefeng Wang wrote:
> 
> [...]
> 
>>>> You need a PCI host controller driver (e.g.
>>>> drivers/pci/host/pci-host-generic.c) and corresponding bindings in DT or
>>>> ACPI.
>>
>> In our inner test, there are some board without pcie host driver(even
>> without pci host controller).
> 
> So I guess those drivers are for devices that are attached to an LPC
> controller that is not part of a PCI host controller, right ?
> 
> BTW, what happened to this (not that I particularly like this patchset) ?

They are working on it, and will upstream again.

> 
> https://lkml.org/lkml/2015/12/29/154
> 
[...]
> 
> I agree with Arnd on this and we need to patch the eg f71805f driver too
> (or we just do not build on ARM) to make it request the IO port region it
> needs to actually probe the device, it is not correct to assume IO space
> is available and mapped, I think that's a driver bug rather than anything
> else, Jean can certainly shed some light here.

Ok, so Jean, would you take a look this? Thanks.

Kefeng
> 
>> Define some arch in/out func instead of generic ops? when in/out vals, check
>> whether or not the pci_iobase is mapped.
> 
> I do not think the problem should be solved in the IO accessors
> implementation, see above.
> 
> Lorenzo
> 
> .
>