From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [PATCH v5 29/29] nios2: Build infrastructure Date: Thu, 30 Oct 2014 12:33:38 +0100 Message-ID: <11875981.eJaWCbGJJT@wuerfel> References: <1414139071-3818-1-git-send-email-lftan@altera.com> <2095416.INZmt8AD1y@wuerfel> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: In-Reply-To: Sender: linux-doc-owner@vger.kernel.org To: Ley Foon Tan Cc: Linux-Arch , "linux-kernel@vger.kernel.org" , "linux-doc@vger.kernel.org" , Chung-Lin Tang List-Id: linux-arch.vger.kernel.org On Thursday 30 October 2014 18:44:37 Ley Foon Tan wrote: > > > > I don't remember what all of these are, but at least some of them seem > > to be concerned with 64-bit division. By convention, we don't provide those > > in the Linux kernel but instead require all code to use the do_div() > > macro instead. > Do you mean kernel doesn't support 64 bit division result for a 32-bit > architecture? Because do_div() only support 32-bit division result for > 32-bit architecture. Correct. If you need a full 64-bit division on a 32-bit kernel, the assumption is that your driver has a bug. Arnd From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.kundenserver.de ([212.227.17.10]:59820 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759059AbaJ3Ldq (ORCPT ); Thu, 30 Oct 2014 07:33:46 -0400 From: Arnd Bergmann Subject: Re: [PATCH v5 29/29] nios2: Build infrastructure Date: Thu, 30 Oct 2014 12:33:38 +0100 Message-ID: <11875981.eJaWCbGJJT@wuerfel> In-Reply-To: References: <1414139071-3818-1-git-send-email-lftan@altera.com> <2095416.INZmt8AD1y@wuerfel> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-arch-owner@vger.kernel.org List-ID: To: Ley Foon Tan Cc: Linux-Arch , "linux-kernel@vger.kernel.org" , "linux-doc@vger.kernel.org" , Chung-Lin Tang Message-ID: <20141030113338.yix9Q6QW-YRR-8Rmmv1K5BVq1LWpntzo5NAHdM-cGyM@z> On Thursday 30 October 2014 18:44:37 Ley Foon Tan wrote: > > > > I don't remember what all of these are, but at least some of them seem > > to be concerned with 64-bit division. By convention, we don't provide those > > in the Linux kernel but instead require all code to use the do_div() > > macro instead. > Do you mean kernel doesn't support 64 bit division result for a 32-bit > architecture? Because do_div() only support 32-bit division result for > 32-bit architecture. Correct. If you need a full 64-bit division on a 32-bit kernel, the assumption is that your driver has a bug. Arnd