Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758717Ab1FBHa0 (ORCPT ); Thu, 2 Jun 2011 03:30:26 -0400 Received: from e38.co.us.ibm.com ([32.97.110.159]:46192 "EHLO e38.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758141Ab1FBHaZ (ORCPT ); Thu, 2 Jun 2011 03:30:25 -0400 Message-ID: <4DE73C04.5050208@in.ibm.com> Date: Thu, 02 Jun 2011 13:00:12 +0530 From: Suzuki Poulose User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.17) Gecko/20110428 Fedora/3.1.10-1.fc14 Thunderbird/3.1.10 MIME-Version: 1.0 To: Benjamin Herrenschmidt CC: Sebastian Andrzej Siewior , "kexec@lists.infradead.org" , linux ppc dev , lkml Subject: Re: [RFC][PATCH] Kexec support for PPC440x References: <4DE345B0.8020505@in.ibm.com> <4DE50617.7090509@linutronix.de> <1306999551.29297.57.camel@pasglop> In-Reply-To: <1306999551.29297.57.camel@pasglop> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2409 Lines: 71 On 06/02/11 12:55, Benjamin Herrenschmidt wrote: > On Tue, 2011-05-31 at 17:15 +0200, Sebastian Andrzej Siewior wrote: >> Suzuki Poulose wrote: >>> Index: powerpc/arch/powerpc/kernel/44x_kexec_mapping.S >>> =================================================================== >>> --- /dev/null >>> +++ powerpc/arch/powerpc/kernel/44x_kexec_mapping.S >> .... >> >>> + * >>> + */ >>> + bl nxtins /* Find our address */ >>> +nxtins: mflr r5 /* Make it accessible */ >> >> Please don't mix labels and instructions. > > With proper indent it's fine as long as he uses numerical relative > labels which should be the case here. For example, the above, it should > look like: > > bl 1f > 1: mflr r5 > >>> + tlbsx r23,0,r5 /* Find entry we are in */ >> >> using tabs instead of spaces would make it look nice. Please also separate >> the arguments of the instruction i.e. >> tlbsx r23, 0, r5 > > That's arguable. If you look at arch/powerpc, we tend not to separate > the arguments ;-) > > Actually I used to, others didn't and I changed my own style. > >>> Index: powerpc/arch/powerpc/kernel/misc_32.S >>> =================================================================== >>> --- powerpc.orig/arch/powerpc/kernel/misc_32.S >>> +++ powerpc/arch/powerpc/kernel/misc_32.S >>> @@ -736,6 +736,28 @@ relocate_new_kernel: >>> mr r5, r31 >>> >>> li r0, 0 >>> +#elif defined(CONFIG_44x)&& !defined(CONFIG_47x) >>> + >>> + mr r29, r3 >>> + mr r30, r4 >>> + mr r31, r5 >>> + >>> +#include "44x_kexec_mapping.S" >> >> The way you setup the 1:1 mapping should be close to what you are doing on >> kernel entry. Isn't it possible to include the file here and in the entry >> code? > > It should just not be #included, what about branching out instead ? This code, i.e, relocate_new_kernel is copied into the control buffer, which will get the first chance to execute before the purgatory. So we may not be able to branch to the code, since we are executing this from a different address and we would invalidate the mapping for the code except the control buffer. Thanks Suzuki -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/