Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 22 Dec 2002 19:21:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 22 Dec 2002 19:21:14 -0500 Received: from dp.samba.org ([66.70.73.150]:28827 "EHLO lists.samba.org") by vger.kernel.org with ESMTP id ; Sun, 22 Dec 2002 19:21:13 -0500 From: Paul Mackerras MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15878.22747.913279.67149@argo.ozlabs.ibm.com> Date: Mon, 23 Dec 2002 11:29:15 +1100 To: Ivan Kokshaysky Cc: Benjamin Herrenschmidt , Linus Torvalds , "Eric W. Biederman" , davidm@hpl.hp.com, linux-kernel@vger.kernel.org Subject: Re: PATCH 2.5.x disable BAR when sizing In-Reply-To: <20021222222106.B30070@localhost.park.msu.ru> References:

<15877.26255.524564.576439@argo.ozlabs.ibm.com> <1040569382.1966.11.camel@zion> <20021222222106.B30070@localhost.park.msu.ru> X-Mailer: VM 7.07 under Emacs 20.7.2 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1629 Lines: 35 Ivan Kokshaysky writes: > Just out of curiosity, formerly you mentioned that said ASIC cannot > be relocated in the PCI address space, why? Firmware issues or anything > else? It's mainly the fact that we have already ioremapped parts of the address space of the ASIC. For example we would have ioremapped the interrupt controller's registers in init_IRQ(), which happens much earlier than PCI probing. If we are using a serial console via one of the serial ports in the ASIC, we would have ioremapped the serial ports by this time. And so on. We could relocate the ASIC if we could find the ioremaps and fix them up, or if we could get to all the drivers and have them re-do their ioremaps. There is no way to do that at the moment, though. Typically the ASIC will have a couple of IDE interfaces, audio, serial, i2c, interrupt controller, wireless ethernet, timer, and PMU (power management unit) interfaces in it, so there are several drivers involved. In fact we don't really need to probe the BARs of the ASIC at all, because the device tree that we get from Open Firmware tells us the size and location of the resources it is using (along with all the other PCI devices in the system). If we could have a platform-specific hook so that we could provide an alternative method for probing the BARs of certain PCI devices, that would let us avoid the whole problem. Paul. - 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/