From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35166) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fhd7t-0004dU-N7 for qemu-devel@nongnu.org; Mon, 23 Jul 2018 11:51:58 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fhd7q-0006eO-L3 for qemu-devel@nongnu.org; Mon, 23 Jul 2018 11:51:57 -0400 Received: from 4.mo4.mail-out.ovh.net ([178.32.98.131]:38834) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fhd7q-0006dL-Bo for qemu-devel@nongnu.org; Mon, 23 Jul 2018 11:51:54 -0400 Received: from player738.ha.ovh.net (unknown [10.109.146.163]) by mo4.mail-out.ovh.net (Postfix) with ESMTP id BFB5A18B66D for ; Mon, 23 Jul 2018 17:51:52 +0200 (CEST) References: <20180710160013.26559-1-peter.maydell@linaro.org> From: =?UTF-8?Q?C=c3=a9dric_Le_Goater?= Message-ID: <286bff36-1137-ea8f-077c-270406ef433d@kaod.org> Date: Mon, 23 Jul 2018 17:51:41 +0200 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH 0/6] accel/tcg: Support execution from MMIO and small MMU regions List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Maydell Cc: qemu-arm , QEMU Developers , "patches@linaro.org" , Richard Henderson , "Emilio G . Cota" , Paolo Bonzini , "Edgar E. Iglesias" , KONRAD Frederic On 07/23/2018 05:17 PM, Peter Maydell wrote: > On 23 July 2018 at 15:57, C=C3=A9dric Le Goater wrote: >> On 07/10/2018 06:00 PM, Peter Maydell wrote: >>> Note for the Xilinx folks: this patchset makes the mmio-exec >>> testcase for running from the SPI flash pass. Cedric: you might >>> like to test the aspeed image you had that relies on execution >>> from an MMIO region too. >> >> I have added a memory region alias at 0x0 on the memory region where >> the first flash device is mapped and all aspeed machines, palmetto, >> romulus, witherspoon booted fine. >> >> More or less 4MB of data access is generated and the slowdown is hardl= y >> noticeable, around one second on a laptop. >> >> I wonder if I should add a bool option to the machine to activate >> or not the feature ? >=20 > I would tend to go with "not" -- if we need the feature then > it's better to run slowly but correctly, and if we don't need > the feature then it doesn't cost us any speed I think. I have chosen a brutal activation (for the moment) : https://github.com/legoater/qemu/commit/10b08c5e8df385bba342f02fa044091= 6203b6fa8 I will send when your patchset is committed. Images used for tests are here :=20 https://openpower.xyz/job/openbmc-build/distro=3Dubuntu,target=3Dromulu= s/lastSuccessfulBuild/artifact/deploy/images/romulus/flash-romulus https://openpower.xyz/job/openbmc-build/distro=3Dubuntu,target=3Dpalmet= to/lastSuccessfulBuild/artifact/deploy/images/palmetto/flash-palmetto https://openpower.xyz/job/openbmc-build/distro=3Dubuntu,target=3Dwither= spoon/lastSuccessfulBuild/artifact/deploy/images/witherspoon/obmc-phospho= r-image-witherspoon.ubi.mtd Thanks, C.=20