Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933774AbcLMSf5 (ORCPT ); Tue, 13 Dec 2016 13:35:57 -0500 Received: from mail-pg0-f66.google.com ([74.125.83.66]:34916 "EHLO mail-pg0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933529AbcLMSf4 (ORCPT ); Tue, 13 Dec 2016 13:35:56 -0500 Date: Wed, 14 Dec 2016 00:05:47 +0530 From: Afzal Mohammed To: Russell King - ARM Linux Cc: Vladimir Murzin , Arnd Bergmann , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH RFC 2/2] ARM: nommu: remap exception base address to RAM Message-ID: <20161213183547.GB4629@afzalpc> References: <20161211131028.3019-1-afzal.mohd.ma@gmail.com> <20161211131255.3221-1-afzal.mohd.ma@gmail.com> <20161213100226.GW14217@n2100.armlinux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20161213100226.GW14217@n2100.armlinux.org.uk> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 887 Lines: 31 Hi, On Tue, Dec 13, 2016 at 10:02:26AM +0000, Russell King - ARM Linux wrote: > On Sun, Dec 11, 2016 at 06:42:55PM +0530, Afzal Mohammed wrote: > > bic r0, r0, #CR_V > > #endif > > mcr p15, 0, r0, c1, c0, 0 @ write control reg > > + > > +#ifdef CONFIG_REMAP_VECTORS_TO_RAM > > + mov r3, #CONFIG_VECTORS_BASE @ read VECTORS_BASE > > + mcr p15, 0, r3, c12, c0, 0 @ write to VBAR > > +#endif > > + > Is there really any need to do this in head.S ? Seeing the high vector configuration done here, pounced upon it :) > I believe it's > entirely possible to do it later - arch/arm/mm/nommu.c:paging_init(). > > Also, if the region setup for the vectors was moved as well, it would > then be possible to check the ID registers to determine whether this > is supported, and make the decision where to locate the vectors base > more dynamically. i will look into it. Regards afzal