From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from foss.arm.com ([217.140.101.70]:50350 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753763AbeBGMi4 (ORCPT ); Wed, 7 Feb 2018 07:38:56 -0500 Subject: Re: [PATCH v5 03/16] media: rkisp1: Add user space ABI definitions To: Hans Verkuil , Shunqian Zheng , linux-rockchip@lists.infradead.org, linux-media@vger.kernel.org Cc: Jose.Abreu@synopsys.com, devicetree@vger.kernel.org, eddie.cai.linux@gmail.com, Joao.Pinto@synopsys.com, heiko@sntech.de, jacob2.chen@rock-chips.com, jeffy.chen@rock-chips.com, zyc@rock-chips.com, linux-kernel@vger.kernel.org, tfiga@chromium.org, Luis.Oliveira@synopsys.com, robh+dt@kernel.org, hans.verkuil@cisco.com, laurent.pinchart@ideasonboard.com, sakari.ailus@linux.intel.com, allon.huang@rock-chips.com, mchehab@kernel.org, linux-arm-kernel@lists.infradead.org References: <1514533978-20408-1-git-send-email-zhengsq@rock-chips.com> <1514533978-20408-4-git-send-email-zhengsq@rock-chips.com> <5b29d890-8c6b-18ff-ade1-1923c25143a0@xs4all.nl> From: Robin Murphy Message-ID: Date: Wed, 7 Feb 2018 12:38:50 +0000 MIME-Version: 1.0 In-Reply-To: <5b29d890-8c6b-18ff-ade1-1923c25143a0@xs4all.nl> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: On 06/02/18 13:14, Hans Verkuil wrote: [...] > The one thing that I worry about is if these structs are the same for > 32 and 64 bit arm. I see some enums and bools in there - in general the storage size of those isn't even guaranteed to be consistent between different compiler implementations on the same platform, let alone across multiple platforms (especially WRT things like GCC's -fshort-enums). In practice, under the standard ABIs for 32-bit and 64-bit Arm[1], I'd expect basic types other than longs and pointers to be pretty much the same; it's the imp-def C stuff I'd be a lot less confident about. Robin. [1]:http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html