From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S270997AbTGPRVj (ORCPT ); Wed, 16 Jul 2003 13:21:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S270991AbTGPRUW (ORCPT ); Wed, 16 Jul 2003 13:20:22 -0400 Received: from smtp-send.myrealbox.com ([192.108.102.143]:7845 "EHLO smtp-send.myrealbox.com") by vger.kernel.org with ESMTP id S270997AbTGPRTM (ORCPT ); Wed, 16 Jul 2003 13:19:12 -0400 Message-ID: <3F158C5F.1000300@myrealbox.com> Date: Thu, 17 Jul 2003 01:33:19 +0800 From: Romit Dasgupta User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.0.1) Gecko/20020830 X-Accept-Language: en-us, en MIME-Version: 1.0 To: linux-kernel@vger.kernel.org Subject: Trivial Change (E820map) : arch/i386/boot/setup.S Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi, After reading the e820 method from Ralf Brown's interrupt list( http://www.ctyme.com/intr/rb-1741.htm) it seems that the es register wont get thrashed. So there is no need to repatedly execute (for getting each map entry) the following two lines inside jmpe820: of seutp.S and thus can be moved out as below. Is there any reason to do it inside? pushw %ds popw %es jmpe820: movl $0x0000e820, %eax # e820, upper word zeroed movl $SMAP, %edx # ascii 'SMAP' movl $20, %ecx # size of the e820rec # pushw %ds # data record. # popw %es Diff ------- ===== setup.S 1.22 vs edited ===== 318a319,320 > pushw %ds > popw %es 324,325c326,327 < pushw %ds # data record. < popw %es --- > # pushw %ds # data record. > # popw %es 1156d1157 < Tested in my i386 machine and here is the relevant portion of dmesg after boot. > Linux version 2.6.0-test1 (root@feynman) (gcc version 3.2 20020903 > (Red Hat Linux 8.0 3.2-7)) #14 Thu Jul 17 01:05:15 SGT 2003 > Video mode to be used for restore is f00 > BIOS-provided physical RAM map: > BIOS-e820: 0000000000000000 - 000000000009f800 (usable) > BIOS-e820: 000000000009f800 - 00000000000a0000 (reserved) > BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved) > BIOS-e820: 0000000000100000 - 0000000017ff0000 (usable) > BIOS-e820: 0000000017ff0000 - 0000000017ffec00 (ACPI data) > BIOS-e820: 0000000017ffec00 - 0000000018000000 (ACPI NVS) > BIOS-e820: 00000000fff80000 - 0000000100000000 (reserved) > 0MB HIGHMEM available. > 383MB LOWMEM available. > On node 0 totalpages: 98288 Regards, -Romit