From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ig0-f182.google.com ([209.85.213.182]:36042 "EHLO mail-ig0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754835AbaIVVAm (ORCPT ); Mon, 22 Sep 2014 17:00:42 -0400 Received: by mail-ig0-f182.google.com with SMTP id hn15so3491933igb.15 for ; Mon, 22 Sep 2014 14:00:41 -0700 (PDT) Date: Mon, 22 Sep 2014 15:00:38 -0600 From: Bjorn Helgaas To: Phil Edworthy Cc: linux-pci@vger.kernel.org, linux-sh@vger.kernel.org, LAKML , Simon Horman , Valentine Barshak , Sergei Shtylyov , Ben Dooks , Jason Gunthorpe , Arnd Bergmann , Liviu Dudau Subject: Re: [PATCH 0/3] Add PCI domain support to R-Car drivers Message-ID: <20140922210038.GJ1880@google.com> References: <1411379470-20639-1-git-send-email-phil.edworthy@renesas.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1411379470-20639-1-git-send-email-phil.edworthy@renesas.com> Sender: linux-pci-owner@vger.kernel.org List-ID: On Mon, Sep 22, 2014 at 10:51:07AM +0100, Phil Edworthy wrote: > The Renesas R-Car devices (r8a7790 and r8a7791) use two PCI controller drivers, > one for an external PCIe slot, the other for an internal PCI bridge to USB > controllers. > > However, they currently do not work at the same time as they use the same PCI > domain and use the same root bus number. We can't use different root bus numbers > due to the way root bus numbers are assigned in pcibios_init_hw() in > arch/arm/kernel/bios32.c. > > Since the two PCI controllers are completely independent, I think it makes sense > to use different PCI domains for them. > > I've marked the third patch as RFC as I am not sure of the impact of enabling > PCI domains for all ARM devices. In the march to 'one kernel to rule them all', > I steered clear of mach specific changes. > > These patches require the following patch from Liviu Dudau: > [PATCH v11 07/10] OF: Introduce helper function for getting PCI domain_nr > Based on comments on this patch from Jason Gunthorpe, there is still the issue > that the domain numbers may change depending on the ordering at probe time. > However, this can be fixed later on by adding the entries in the DT files. > > > Phil Edworthy (3): > PCI: rcar-pcie: Add call to get domain nr > PCI: rcar-internal-pci: Add call to get domain nr > ARM: Enable PCI domains I'm deferring these for now because they depend on Liviu's work, which I haven't merged yet, and I suspect some minor adaptation will be required here. For what it's worth, I agree with Rob's hesitation about mixing lookup with domain number allocation in of_pci_get_domain_nr(). That seems unnecessarily complicated. > arch/arm/Kconfig | 2 +- > drivers/pci/host/pci-rcar-gen2.c | 6 ++++++ > drivers/pci/host/pcie-rcar.c | 9 ++++++--- > 3 files changed, 13 insertions(+), 4 deletions(-) > > -- > 2.1.0 >