Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261791AbUDJHme (ORCPT ); Sat, 10 Apr 2004 03:42:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261979AbUDJHme (ORCPT ); Sat, 10 Apr 2004 03:42:34 -0400 Received: from zcars04f.nortelnetworks.com ([47.129.242.57]:28619 "EHLO zcars04f.nortelnetworks.com") by vger.kernel.org with ESMTP id S261791AbUDJHmc (ORCPT ); Sat, 10 Apr 2004 03:42:32 -0400 Message-ID: <4077A542.8030108@nortelnetworks.com> Date: Sat, 10 Apr 2004 03:41:54 -0400 X-Sybari-Space: 00000000 00000000 00000000 00000000 From: Chris Friesen User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6) Gecko/20040113 X-Accept-Language: en-us, en MIME-Version: 1.0 To: linuxppc-dev@lists.linuxppc.org, linux-kernel@vger.kernel.org Subject: want to clarify powerpc assembly conventions in head.S and entry.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 Content-Length: 903 Lines: 27 I'm doing some work in head.S and entry.S, and I just wanted to make sure that I had the conventions down. According to the docs I read, r0 and r3-12 are caller-saves. They seem to be saved in EXCEPTION_PROLOG_2 (head.S) and restored in ret_from_except() (entry.S). Thus, if I add code in entry.S I should be able to use any of those registers, without having to worry about restoring them myself--correct? Also, I'm a bit confused about the three instances of the following line in entry.S: stwcx. r0,0,r1 /* to clear the reservation */ I don't see the corresponding lwarx instruction. What reservation is it referring to? Thanks, Chris - 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/