Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932151Ab3GYWeL (ORCPT ); Thu, 25 Jul 2013 18:34:11 -0400 Received: from comal.ext.ti.com ([198.47.26.152]:48030 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755292Ab3GYWeI (ORCPT ); Thu, 25 Jul 2013 18:34:08 -0400 Message-ID: <51F1A7AA.8080700@ti.com> Date: Thu, 25 Jul 2013 18:33:14 -0400 From: Santosh Shilimkar User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/17.0 Thunderbird/17.0 MIME-Version: 1.0 To: Tejun Heo CC: Yinghai Lu , Russell King - ARM Linux , , Linux Kernel Mailing List , Catalin Marinas , Will Deacon , Nicolas Pitre , Ingo Molnar , Andrew Morton , "H. Peter Anvin" , Benjamin Herrenschmidt , Paul Mackerras , "David S. Miller" , "sparclinux@vger.kernel.org" , Sam Ravnborg , Subject: Re: [PATCH] WIP: HACK: LPAE, BOOTMEM and NO_BOOTMEM References: <1372467663-31425-1-git-send-email-santosh.shilimkar@ti.com> <20130629152959.GB31339@mtj.dyndns.org> <20130629172123.GA3353@n2100.arm.linux.org.uk> <20130629175743.GA382@mtj.dyndns.org> <20130629195549.GE3353@n2100.arm.linux.org.uk> <51D18DBA.6090608@ti.com> In-Reply-To: <51D18DBA.6090608@ti.com> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2432 Lines: 61 Tejun, On Monday 01 July 2013 10:10 AM, Santosh Shilimkar wrote: > On Saturday 29 June 2013 04:08 PM, Yinghai Lu wrote: >> On Sat, Jun 29, 2013 at 12:55 PM, Russell King - ARM Linux >> wrote: >>> On Sat, Jun 29, 2013 at 12:29:55PM -0700, Yinghai Lu wrote: >>>>>> On these SoCs which Santosh is working on, the main physical memory >>>>>> mapping is above 4GB, with just a small alias below 4GB to allow the >>>>>> system to boot without the MMU being on, as they may have more than >>>>>> 4GB of RAM. As I understand it, the small alias below 4GB is not >>>>>> suitable for use as a "lowmem" mapping. >>>> >>>> is that 32bit ARM or 64bit ARM? >>> >>> Only 32-bit has LPAE. Such things don't make sense on 64-bit CPUs. >> > Thanks Russell for clarifying the issue on the thread. Another major > reason of not being to use 32 bit alias address space for lowmem > is that address space isn't coherent on the SOC am dealing with. > >> 32bit ARM does not support NO_BOOTMEM yet. >> >> arch/arc/Kconfig: select NO_BOOTMEM >> arch/arm64/Kconfig: select NO_BOOTMEM >> arch/sparc/Kconfig: select NO_BOOTMEM >> arch/x86/Kconfig:config NO_BOOTMEM >> >> >> so may need to >> 1. make 32bit ARM to use NO_BOOTMEM at first. >> > Sorry. I should have mentioned that in the change-log. > I have been carrying some WIP patches for ARM. Will post them > on ARM list after finishing remainder of the testing. > >> 2 .we can add alloc_memblock as MACRO or inline for bootmem arches, >> >> 3. NO_BOOTMEM arches will have alloc_memblock in nobootmem.c >> >> 4. replace alloc_bootmem calling with alloc_memblock calling in core code. >> > Great that we all agree to see back of nobootmem.c and have a direct > memblock API. Will be happy to help in conversion to proposed new interfaces > if I can get the alloc_memblock API and core related changes. > > Will be good to know who is going to create proposed memblock API > so that we all can collaborate in conversion. > Any comments here. I would like to know your plan for the new API. You might have seen on the ARM no-bootmem thread, we started to move ARM to nobootmem with Russell's help. Regards, Santosh -- 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/