From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 29 Jun 2001 14:09:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 29 Jun 2001 14:08:56 -0400 Received: from mailout03.sul.t-online.com ([194.25.134.81]:43527 "EHLO mailout03.sul.t-online.de") by vger.kernel.org with ESMTP id ; Fri, 29 Jun 2001 14:08:46 -0400 Message-ID: <3B3CC466.9CAC4365@t-online.de> Date: Fri, 29 Jun 2001 20:09:42 +0200 From: Gunther.Mayer@t-online.de (Gunther Mayer) X-Mailer: Mozilla 4.77 [en] (X11; U; Linux 2.4.5 i686) X-Accept-Language: en MIME-Version: 1.0 To: Andre Hedrick CC: linux-kernel@vger.kernel.org Subject: Re: Patch(2.4.5): Fix PCMCIA ATA/IDE freeze (w/ PCI add-in cards)V3 In-Reply-To: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Andre Hedrick wrote: > > That is a legacy bit from ATA-2 but it is one of those things you can not > get rid of :-( even thou things are obsoleted, they are not retired. > This means that you have to go back into the past to see how it was used, > silly! I hope you agree to that point. No, in ANSI X3.279-1996, "AT Attachment Interface with Extensions (ATA-2)", Approved September 11, 1996 , control register bit 3-7 are reserved. However ANSI X3.221-1994, "AT Attachment Interface for Disk Drives", Approved May 12, 1994, bit3 is "1" and bits 4-7 are "x". No further explanation. How far back must we go, to get the sense ? > > This is the drive->ctrl register pointer. > > outp(drive->ctl|0x02, IDE_CONTROL_REG); > > typedef union { > unsigned all : 8; /* all of the bits together */ > struct { > unsigned bit0 : 1; > unsigned nIEN : 1; /* device INTRQ to host */ > unsigned SRST : 1; /* host soft reset bit */ > unsigned bit3 : 1; /* ATA-2 thingy */ > unsigned reserved456 : 3; > unsigned HOB : 1; /* 48-bit address ordering */ > } b; > } control_t; > > This is a new struct that is to be added for 48-bit addressing and it will > reflect drive->ctl soon. I have not decided how to use it best or at all, > but it has meaning and once I add-in the real def of bit3 then I will not > need to look it up again.