From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mms2.broadcom.com ([216.31.210.18]:2371 "EHLO mms2.broadcom.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755111Ab1EXKBn (ORCPT ); Tue, 24 May 2011 06:01:43 -0400 Message-ID: <4DDB81FD.2020903@broadcom.com> (sfid-20110524_120200_395506_4F6063FD) Date: Tue, 24 May 2011 12:01:33 +0200 From: "Arend van Spriel" MIME-Version: 1.0 To: "Alan Cox" cc: "Andrew Morton" , "linux-kernel@vger.kernel.org" , "linux-wireless@vger.kernel.org" , "John W. Linville" , "Dan Carpenter" Subject: Re: [RFC] lib: crc8: add new library module providing crc8 algorithm References: <1306010973-5625-1-git-send-email-arend@broadcom.com> <20110522122325.108b1c86@lxorguk.ukuu.org.uk> <4DD905CC.8040407@broadcom.com> <20110522151959.7fd6e87e@lxorguk.ukuu.org.uk> <4DDB622B.1050005@broadcom.com> <20110524104404.336c765f@lxorguk.ukuu.org.uk> In-Reply-To: <20110524104404.336c765f@lxorguk.ukuu.org.uk> Content-Type: text/plain; charset=iso-8859-1; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On 05/24/2011 11:44 AM, Alan Cox wrote: > On Tue, 24 May 2011 09:45:47 +0200 > "Arend van Spriel" wrote: > >> On 05/22/2011 04:19 PM, Alan Cox wrote: >>> Is it just used for wireless in this form ? >>> >>> See the n_gsm and bluetooth code for what I think is the same crc >>> algorithm but in reverse bit order . >> Hi Alan, >> >> Look into the code in n_gsm and bluetooth code. The algorithm is the >> same, but except for the bit order it also is using a different >> polynomial. My current implementation has a fixed table. I could do the >> table generation runtime with the polynomial and the bit order as >> parameters. That would make it more general purpose. > Probably not worth it - its so tiny a piece of code anyway (< 500 bytes > or so) that it's going to be bigger not smaller if you do that ! Hi Alan, Not sure whether you mean the source code or the object code. I build kernel with debug symbols so the sizes are bit higher. fixed table: -rw-r--r-- 1 arend arend 1859 2011-05-24 11:53 crc8.o custom table: -rw-r--r-- 1 arend arend 2215 2011-05-24 11:58 crc8.o The size increase is not that big. Gr. AvS -- Almost nobody dances sober, unless they happen to be insane. -- H.P. Lovecraft --