Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756514AbbLGWnc (ORCPT ); Mon, 7 Dec 2015 17:43:32 -0500 Received: from mail.kernel.org ([198.145.29.136]:52976 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756117AbbLGWn3 (ORCPT ); Mon, 7 Dec 2015 17:43:29 -0500 Date: Mon, 7 Dec 2015 16:43:14 -0600 From: Bjorn Helgaas To: David Daney Cc: linux-kernel@vger.kernel.org, Bjorn Helgaas , linux-pci@vger.kernel.org, Will Deacon , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, Marc Zyngier , David Daney Subject: Re: [PATCH v2] PCI: generic: Add support for Cavium ThunderX PCIe root complexes. Message-ID: <20151207224314.GE14429@localhost> References: <1442967415-13595-1-git-send-email-ddaney.cavm@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1442967415-13595-1-git-send-email-ddaney.cavm@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4614 Lines: 122 Hi David, On Tue, Sep 22, 2015 at 05:16:55PM -0700, David Daney wrote: > From: David Daney > > The config space for external PCIe root complexes on some Cavium > ThunderX SoCs is very similar to CAM and ECAM, but differs in the > shift values that have to be applied to the bus and devfn numbers to > compose that address window offset. These root complexes also have > the interesting property that there is no root bridge, so the standard > manner of limiting scanning to only the first device doesn't work. We > can use the standard pci-host-generic driver if we make a minor > addition to handle these differences, so we... > > Add a mapping function for ThunderX PCIe root complexes with a bus > shift of 24 and devfn shift of 16. Ignore accesses for devices other > than the first device on the primary bus. > > Document the whole thing in devicetree/bindings/pci/host-generic-pci.txt > > Signed-off-by: David Daney > Acked-by: Will Deacon I'm trying to sort the ThunderX stuff out. Can you repost the current stuff so we can see it all together? Thanks, Bjorn > --- > > This patch depends on: > https://lkml.org/lkml/2015/9/22/1189 > > Changes from v1: > > - Added Acked-by: > > - Removed two patches from the set that were somewhat unrelated. > > .../devicetree/bindings/pci/host-generic-pci.txt | 8 +++--- > drivers/pci/host/pci-host-generic.c | 29 ++++++++++++++++++++++ > 2 files changed, 34 insertions(+), 3 deletions(-) > > diff --git a/Documentation/devicetree/bindings/pci/host-generic-pci.txt b/Documentation/devicetree/bindings/pci/host-generic-pci.txt > index 105a968..a5aed0f 100644 > --- a/Documentation/devicetree/bindings/pci/host-generic-pci.txt > +++ b/Documentation/devicetree/bindings/pci/host-generic-pci.txt > @@ -14,9 +14,11 @@ tree bindings communicated in pci.txt: > > Properties of the host controller node: > > -- compatible : Must be "pci-host-cam-generic" or "pci-host-ecam-generic" > - depending on the layout of configuration space (CAM vs > - ECAM respectively). > +- compatible : One of the following with bus:devfn:reg mapped to the > + PCI config space address window in the bit positions shown: > + "pci-host-cam-generic" -- 'CAM' bits 16:8:0 > + "pci-host-ecam-generic" -- 'ECAM' bits 20:12:0 > + "cavium,pci-host-thunder-pem" -- bits 24:16:0 > > - device_type : Must be "pci". > > diff --git a/drivers/pci/host/pci-host-generic.c b/drivers/pci/host/pci-host-generic.c > index b163fdc..853f6f6 100644 > --- a/drivers/pci/host/pci-host-generic.c > +++ b/drivers/pci/host/pci-host-generic.c > @@ -91,6 +91,32 @@ static struct gen_pci_cfg_bus_ops gen_pci_cfg_ecam_bus_ops = { > } > }; > > +static void __iomem *gen_pci_map_cfg_bus_thunder_pem(struct pci_bus *bus, > + unsigned int devfn, > + int where) > +{ > + struct gen_pci *pci = bus->sysdata; > + resource_size_t idx = bus->number - pci->cfg.bus_range->start; > + > + /* > + * Thunder PEM is a PCIe RC, but without a root bridge. On > + * the primary bus, ignore accesses for devices other than > + * the first device. > + */ > + if (idx == 0 && (devfn & ~7u)) > + return NULL; > + return pci->cfg.win[idx] + ((devfn << 16) | where); > +} > + > +static struct gen_pci_cfg_bus_ops gen_pci_cfg_thunder_pem_bus_ops = { > + .bus_shift = 24, > + .ops = { > + .map_bus = gen_pci_map_cfg_bus_thunder_pem, > + .read = pci_generic_config_read, > + .write = pci_generic_config_write, > + } > +}; > + > static const struct of_device_id gen_pci_of_match[] = { > { .compatible = "pci-host-cam-generic", > .data = &gen_pci_cfg_cam_bus_ops }, > @@ -98,6 +124,9 @@ static const struct of_device_id gen_pci_of_match[] = { > { .compatible = "pci-host-ecam-generic", > .data = &gen_pci_cfg_ecam_bus_ops }, > > + { .compatible = "cavium,pci-host-thunder-pem", > + .data = &gen_pci_cfg_thunder_pem_bus_ops }, > + > { }, > }; > MODULE_DEVICE_TABLE(of, gen_pci_of_match); > -- > 1.9.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-pci" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- 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/