Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 13 Apr 2001 15:45:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 13 Apr 2001 15:44:55 -0400 Received: from router-100M.swansea.linux.org.uk ([194.168.151.17]:51725 "EHLO the-village.bc.nu") by vger.kernel.org with ESMTP id ; Fri, 13 Apr 2001 15:44:51 -0400 Subject: Re: device driver questions To: friedrich_s@crane.navy.mil (Friedrich Steven E CONT CNIN) Date: Fri, 13 Apr 2001 20:46:58 +0100 (BST) Cc: linux-kernel@vger.kernel.org ("Linux Kernel List (E-mail)") In-Reply-To: from "Friedrich Steven E CONT CNIN" at Apr 13, 2001 02:33:38 PM X-Mailer: ELM [version 2.5 PL1] MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-Id: From: Alan Cox Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > My device shows up in /proc/iomem even before I load my device driver, > indicating that the pci subsystem mapped it into the kernel pages. But bar0 Actually the addresses you see there are physical bus addresses not neccessarily and on x86 quite likely not actually mapped. > Why didn't the pci subsystem configure the device to appear on a page > boundary? The device didnt ask to be on a page boundary > the user program? I know I could create an ioctl call, but I would think > there must be some other method already in place, since this would affect > all pci devices. If you want to mmap the device then you really want to put the device in its own 4K aligned 4K sized PCI window, otherwise adjacent devices will become accessible too and that might not be desirable. Or you could avoid providing mmap. Alan - 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/