Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755810AbaLHW4a (ORCPT ); Mon, 8 Dec 2014 17:56:30 -0500 Received: from gate.crashing.org ([63.228.1.57]:40019 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754066AbaLHW42 (ORCPT ); Mon, 8 Dec 2014 17:56:28 -0500 Message-ID: <1418079372.13358.9.camel@kernel.crashing.org> Subject: Re: [PATCH] PCI: Clear bridge MEM_64 flag if one child does not support it From: Benjamin Herrenschmidt To: Yinghai Lu Cc: Bjorn Helgaas , Gavin Shan , Marek =?ISO-8859-1?Q?Kord=EDk?= , zermond@gmail.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Date: Tue, 09 Dec 2014 09:56:12 +1100 In-Reply-To: <1418075552-26495-1-git-send-email-yinghai@kernel.org> References: <1418075552-26495-1-git-send-email-yinghai@kernel.org> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.12.7-0ubuntu1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2014-12-08 at 13:52 -0800, Yinghai Lu wrote: > 2. or scan the children resource other than ROM to clear bridge MEM_64 > for mmio pref. > > The patch is using second way so will keep child mmio pref into bridge > mmio pref range. That means that having a single ROM BAR that is 32-bit and prefetchable will downgrade the entire window to 32-bit ? That's not going to work either. I have GPUs with 16G BARs for example... suddenly they don't fit anaymore because we downgraded the window to 32 bit because somewhere there's a 32-bit pref resource ? That will break more than it fixes... Ben. -- 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/