From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C7484C32751 for ; Wed, 7 Aug 2019 15:19:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A2F3221E73 for ; Wed, 7 Aug 2019 15:19:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388355AbfHGPTE convert rfc822-to-8bit (ORCPT ); Wed, 7 Aug 2019 11:19:04 -0400 Received: from eu-smtp-delivery-151.mimecast.com ([207.82.80.151]:26904 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387543AbfHGPTE (ORCPT ); Wed, 7 Aug 2019 11:19:04 -0400 Received: from AcuMS.aculab.com (156.67.243.126 [156.67.243.126]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-58-vbBGLUz5N52_YU_A_1ip9w-1; Wed, 07 Aug 2019 16:19:00 +0100 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) by AcuMS.aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Wed, 7 Aug 2019 16:18:59 +0100 Received: from AcuMS.Aculab.com ([fe80::43c:695e:880f:8750]) by AcuMS.aculab.com ([fe80::43c:695e:880f:8750%12]) with mapi id 15.00.1347.000; Wed, 7 Aug 2019 16:18:59 +0100 From: David Laight To: 'Sudeep Holla' , "linux-arm-kernel@lists.infradead.org" CC: "linux-kernel@vger.kernel.org" , "Philipp Zabel" Subject: RE: [PATCH] firmware: arm_scmi: Use {get,put}_unaligned_le32 accessors Thread-Topic: [PATCH] firmware: arm_scmi: Use {get,put}_unaligned_le32 accessors Thread-Index: AQHVTSAtyuEmH657y0Gt9ART6WUBkKbvzBcw Date: Wed, 7 Aug 2019 15:18:59 +0000 Message-ID: <4102ce79ef7a4f5ba819663d072bccc8@AcuMS.aculab.com> References: <20190807130038.26878-1-sudeep.holla@arm.com> In-Reply-To: <20190807130038.26878-1-sudeep.holla@arm.com> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 X-MC-Unique: vbBGLUz5N52_YU_A_1ip9w-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sudeep Holla > Sent: 07 August 2019 14:01 > > Instead of type-casting the {tx,rx}.buf all over the place while > accessing them to read/write __le32 from/to the firmware, let's use > the nice existing {get,put}_unaligned_le32 accessors to hide all the > type cast ugliness. Why the 'unaligned' accessors? > - *(__le32 *)t->tx.buf = cpu_to_le32(id); > + put_unaligned_le32(id, t->tx.buf); These will be expensive if the cpu doesn't support them. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)