Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753481AbYLARIt (ORCPT ); Mon, 1 Dec 2008 12:08:49 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752187AbYLARIk (ORCPT ); Mon, 1 Dec 2008 12:08:40 -0500 Received: from mail.sf-mail.de ([62.27.20.61]:42533 "EHLO mail.sf-mail.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751936AbYLARIj (ORCPT ); Mon, 1 Dec 2008 12:08:39 -0500 From: Rolf Eike Beer To: Trent Piepho Subject: Re: [PATCH] fakephp: Allocate PCI resources before adding the device Date: Mon, 1 Dec 2008 18:08:30 +0100 User-Agent: KMail/1.9.10 Cc: "Darrick J. Wong" , Alex Chiang , "linux-kernel" , Jesse Barnes , "linux-pci" References: <20081125212422.22631.69619.stgit@elm3a70.beaverton.ibm.com> <200811281942.31754.eike-kernel@sf-tec.de> In-Reply-To: MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart6244774.97xlM0aTeu"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit Message-Id: <200812011808.31906.eike-kernel@sf-tec.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2808 Lines: 70 --nextPart6244774.97xlM0aTeu Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Trent Piepho wrote: > On Fri, 28 Nov 2008, Rolf Eike Beer wrote: > > Trent Piepho wrote: > > > On Wed, 26 Nov 2008, Darrick J. Wong wrote: > > > > On Wed, Nov 26, 2008 at 03:55:35PM -0700, Alex Chiang wrote: > > > > > > Maybe it's different on powerpc then? My pseudo-hotplugable > > > > > > device is also the only thing connected to the PCI-E host bus > > > > > > controller. At boot the controller is empty and so I think some > > > > > > code to enable its BARs gets skipped. But without the > > > > > > pci_enable_device(), I get this: > > > > > > > > > > > > 01:00.0 Signal processing controller: Freescale Semiconductor I= nc > > > > > > Aurora Nexus Trace Interface Flags: fast devsel, IRQ 255 > > > > > > Memory at 40000000 (64-bit, prefetchable) [disabled] > > > > > > [size=3D4K] > > > > > > > > Are you referring to this? ^^^^^^^^^^ > > > > > > > > Without seeing the raw dump of the PCI config space, it looks to me > > > > like the memory space enable bit of the PCICMD register is unset.=20 > > > > Probably the device driver should call pci_enable_device() at init > > > > time, though I suppose you did say earlier that there is no driver. > > > > > > Yes, that's it. It seems like since the BARs are normally enabled > > > after a device is scanned at boot time that they should also be enabl= ed > > > when a device is found by a fakephp rescan. So I thought it seemed > > > reasonable to put pci_enable_device() in fakephp. > > > > No, pci_enable_device() will be called by the device driver. The hotplug > > drivers have nothing to do with that. > > I guess you didn't read the part about there not being a device driver? I read it, but that's the way a kernel works: if you want to talk to a devi= ce,=20 get a driver. You can write a rather minimal one that does only=20 pci_enable_device() on probe and pci_disable_device() on remove. Try the on= e=20 posted by Chris Wright in "[PATCH 2/2] PCI: pci-stub module to reserve pci= =20 device" as a starting point. Eike --nextPart6244774.97xlM0aTeu Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.9 (GNU/Linux) iEYEABECAAYFAkk0Gg8ACgkQXKSJPmm5/E7fqwCfU+j12oWsQ8GxQORTo3gsbL7p 7kMAnjeymkF97/IkqQQPASbTPYYpbGb0 =qJm8 -----END PGP SIGNATURE----- --nextPart6244774.97xlM0aTeu-- -- 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/