From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 53C291A1E0A for ; Mon, 12 Sep 2016 06:48:55 -0700 (PDT) Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 79B868E3E0; Mon, 12 Sep 2016 13:48:54 +0000 (UTC) Received: from lacos-laptop-7.usersys.redhat.com (ovpn-116-102.phx2.redhat.com [10.3.116.102]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u8CDmqwh031399; Mon, 12 Sep 2016 09:48:52 -0400 To: Ard Biesheuvel , "Yao, Jiewen" References: <1473685561-1418-1-git-send-email-ard.biesheuvel@linaro.org> <74D8A39837DF1E4DA445A8C0B3885C50385FCEB6@shsmsx102.ccr.corp.intel.com> Cc: "edk2-devel@lists.01.org" , "Gao, Liming" , "Zeng, Star" , "Tian, Feng" , "Ni, Ruiyu" , "leif.lindholm@linaro.org" From: Laszlo Ersek Message-ID: <449c21bc-ddfc-697a-bc25-7daa05485b6c@redhat.com> Date: Mon, 12 Sep 2016 15:48:51 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Mon, 12 Sep 2016 13:48:54 +0000 (UTC) Subject: Re: [PATCH] MdeModulePkg/PciBusDxe: make BAR degradation dependent on OPROM presence X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 12 Sep 2016 13:48:55 -0000 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit On 09/12/16 15:16, Ard Biesheuvel wrote: > On 12 September 2016 at 14:15, Yao, Jiewen wrote: >> HI Ard >> We should not let MdeModulePkg depend on IntelFrameworkPkg. >> You patch violates the dependency rule. >> I suggest we figure out other solution to resolve the problem. >> > > Yes, please. And please keep us informed about any solutions you come up with. * One idea is to parse the PCI expansion ROM in order to see what image types are contained within. If there is no (Code type == 0x00) image in the oprom, then the oprom is useless for legacy boot anyway, so it shouldn't trigger degradation. Unfortunately, this wouldn't help a lot in practice, since it's surely going to be years before hw vendors migrate to pure UEFI oproms on their graphics and network cards. :( * Another idea is to check a dynamic PCD that the platform can set. New PCDs are frowned upon in MdeModulePkg however, so I don't expect this to be a popular fix. Thanks Laszlo