From mboxrd@z Thu Jan 1 00:00:00 1970 From: Grant Grundler Subject: Re: [PATCH 4/4] bnx2i: Add bnx2i iSCSI driver. Date: Tue, 26 May 2009 10:03:35 -0700 Message-ID: References: <1243113110-29635-1-git-send-email-mchan@broadcom.com> <1243113110-29635-5-git-send-email-mchan@broadcom.com> <1243356541.29526.27.camel@HP1> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from smtp-out.google.com ([216.239.45.13]:9030 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756215AbZEZRDh convert rfc822-to-8bit (ORCPT ); Tue, 26 May 2009 13:03:37 -0400 Received: from zps76.corp.google.com (zps76.corp.google.com [172.25.146.76]) by smtp-out.google.com with ESMTP id n4QH3cOv014828 for ; Tue, 26 May 2009 10:03:38 -0700 Received: from qyk42 (qyk42.prod.google.com [10.241.83.170]) by zps76.corp.google.com with ESMTP id n4QH2fOs006999 for ; Tue, 26 May 2009 10:03:37 -0700 Received: by qyk42 with SMTP id 42so5532719qyk.7 for ; Tue, 26 May 2009 10:03:37 -0700 (PDT) In-Reply-To: <1243356541.29526.27.camel@HP1> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Michael Chan Cc: "James.Bottomley@hansenpartnership.com" , "michaelc@cs.wisc.edu" , "davem@davemloft.net" , "linux-scsi@vger.kernel.org" , "open-iscsi@googlegroups.com" , Anil Veerabhadrappa , Benjamin Li On Tue, May 26, 2009 at 9:49 AM, Michael Chan wrot= e: =2E.. > Hi Grant, these are what we call "DMA control structures" as opposed = to > DMA packet data. =C2=A0Our chips are configured to do an additional 3= 2-bit > endian swap on all DMA control structures. =C2=A0This way, all 32-bit= control > fields (such as length, status, etc) will come out right when the dri= ver > reads these fields. > > If everything was defined as u32 in all these control structures, we > wouldn't have to add the #ifdef. =C2=A0u8 and u16 fields have to be d= efined > this way or else big endian CPUs would read the wrong offset. > > If you look at some of the control structures in tg3.h, you'll see th= e > same thing. Ah ok...so the chip is programmed configured to know about host endiane= ss. I'm familiar with tg3 having that and just hadn't noticed it here yet. thanks, grant -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html