Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754911Ab1FFIvj (ORCPT ); Mon, 6 Jun 2011 04:51:39 -0400 Received: from www.linutronix.de ([62.245.132.108]:43969 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753000Ab1FFIvh (ORCPT ); Mon, 6 Jun 2011 04:51:37 -0400 Message-ID: <4DEC950E.1020105@linutronix.de> Date: Mon, 06 Jun 2011 10:51:26 +0200 From: Sebastian Andrzej Siewior User-Agent: Mozilla-Thunderbird 2.0.0.24 (X11/20100329) MIME-Version: 1.0 To: Suzuki Poulose CC: Simon Horman , "kexec@lists.infradead.org" , Ananth N Mavinakayanahalli , lkml , Josh Boyer , linux ppc dev , Vivek Goyal Subject: Re: [RFC][PATCH] powerpc: Use the #address-cells information to parse memory/reg References: <4DC923C4.6080707@in.ibm.com> <4DC92784.2040001@in.ibm.com> <20110510134152.GB18537@in.ibm.com> <4DCA285D.2080006@in.ibm.com> <4DE3396E.4090801@in.ibm.com> <4DEC7F49.8060000@in.ibm.com> In-Reply-To: <4DEC7F49.8060000@in.ibm.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2684 Lines: 88 Suzuki Poulose wrote: > Could you please let me know your thoughts/comments about this patch ? I'm mostly fine with it. Maaxim copied fs2dt.c from ppc64 to ppc. So I guess ppc64 has the same problem. ARM and MIPS is soon having DT support and kexec is probably also on their list so I would hate to see them to either copy the DT parsing file or having their own implementation. Maybe we should try to use libfdt for dt parsing. It has /proc import support so it should be fine for our needs. It is already in tree and used by ppc32 if a basic dtb is specified. I'm not sure if the /proc interface is part of dtc or libfdt. I'm not saying this has to be done now but maybe later before ARM and/or MIPS comes along needs something similar for their needs. If the libfdt is too complex for sucking in the dtb from /proc then maybe something else that generic and can be shared between booth ppc architectures and the other ones. > Thanks > Suzuki > >> >> Index: kexec-tools-2.0.4/kexec/arch/ppc/kexec-ppc.c >> =================================================================== >> --- kexec-tools-2.0.4.orig/kexec/arch/ppc/kexec-ppc.c >> +++ kexec-tools-2.0.4/kexec/arch/ppc/kexec-ppc.c >> @@ -34,6 +35,92 @@ unsigned int rtas_base, rtas_size; >> int max_memory_ranges; >> const char *ramdisk; >> >> +/* >> + * Reads the #address-cells and #size-cells on this platform. >> + * This is used to parse the memory/reg info from the device-tree >> + */ >> +int init_memory_region_info() >> +{ >> + size_t res = 0; >> + FILE *fp; >> + char *file; >> + >> + file = "/proc/device-tree/#address-cells"; >> + fp = fopen(file, "r"); >> + if (!fp) { >> + fprintf(stderr,"Unable to open %s\n", file); >> + return -1; >> + } >> + >> + res = fread(&dt_address_cells,sizeof(unsigned long),1,fp); >> + if (res != 1) { >> + fprintf(stderr,"Error reading %s\n", file); >> + return -1; >> + } >> + fclose(fp); >> + dt_address_cells *= sizeof(unsigned long); This should be sizeof(unsigned int). I know we on 32bit. >> + file = "/proc/device-tree/#size-cells"; >> + fp = fopen(file, "r"); >> + if (!fp) { >> + fprintf(stderr,"Unable to open %s\n", file); >> + return -1; >> + } >> + >> + res = fread(&dt_size_cells,sizeof(unsigned long),1,fp); >> + if (res != 1) { >> + fprintf(stderr,"Error reading %s\n", file); >> + return -1; >> + } >> + fclose(fp); >> + dt_size_cells *= sizeof(unsigned long); same here. >> + >> + return 0; >> +} >> + Sebastian -- 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/