Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932995AbcKPQoZ (ORCPT ); Wed, 16 Nov 2016 11:44:25 -0500 Received: from fllnx210.ext.ti.com ([198.47.19.17]:16248 "EHLO fllnx210.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932541AbcKPQoM (ORCPT ); Wed, 16 Nov 2016 11:44:12 -0500 Subject: Re: [PATCH 3/4] PCI: dra7xx: Add support to force RC to work in GEN1 mode To: Bjorn Helgaas References: <1476190715-16884-1-git-send-email-kishon@ti.com> <1476190715-16884-4-git-send-email-kishon@ti.com> <20161111211528.GF9868@bhelgaas-glaptop.roam.corp.google.com> <8ecc1325-365d-bdec-d435-729e0ea49d20@ti.com> <20161114212400.GA19092@bhelgaas-glaptop.roam.corp.google.com> CC: Bjorn Helgaas , Rob Herring , , , , , , Shawn Lin From: Kishon Vijay Abraham I Message-ID: Date: Wed, 16 Nov 2016 22:14:00 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <20161114212400.GA19092@bhelgaas-glaptop.roam.corp.google.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2039 Lines: 52 Hi Bjorn, On Tuesday 15 November 2016 02:54 AM, Bjorn Helgaas wrote: > [+cc Shawn] > > On Sat, Nov 12, 2016 at 12:40:10PM +0530, Kishon Vijay Abraham I wrote: >> Hi, >> >> On Saturday 12 November 2016 02:45 AM, Bjorn Helgaas wrote: >>> Hi Kishon, >>> >>> On Tue, Oct 11, 2016 at 06:28:34PM +0530, Kishon Vijay Abraham I wrote: >>>> PCIe in AM57x/DRA7x devices is by default >>>> configured to work in GEN2 mode. However there >>>> may be situations when working in GEN1 mode is >>>> desired. One example is limitation i925 (PCIe GEN2 >>>> mode not supported at junction temperatures < 0C). >>>> >>>> Add support to force Root Complex to work in GEN1 >>>> mode if so desired, but don't force GEN1 mode on >>>> any board just yet. >>>> >>>> Signed-off-by: Kishon Vijay Abraham I >>>> Signed-off-by: Sekhar Nori >>>> --- >>>> Documentation/devicetree/bindings/pci/ti-pci.txt | 1 + >>>> drivers/pci/host/pci-dra7xx.c | 27 ++++++++++++++++++++++ >>>> 2 files changed, 28 insertions(+) >>>> >>>> diff --git a/Documentation/devicetree/bindings/pci/ti-pci.txt b/Documentation/devicetree/bindings/pci/ti-pci.txt >>>> index 60e2516..a3d6ca3 100644 >>>> --- a/Documentation/devicetree/bindings/pci/ti-pci.txt >>>> +++ b/Documentation/devicetree/bindings/pci/ti-pci.txt >>>> @@ -25,6 +25,7 @@ PCIe Designware Controller >>>> >>>> Optional Property: >>>> - gpios : Should be added if a gpio line is required to drive PERST# line >>>> + - ti,pcie-is-gen1 : Force the PCIe controller to work in GEN1 (2.5 GT/s). >>> >>> Can we use "max-link-speed" so it's similar to imx6? >> >> yeah, maybe we should make it a generic PCI property? > > I forgot that Shawn has already done this! I had already merged those > patches on pci/host-rockchip, but I moved them to pci/host since > they're not Rockchip-specific. Can you take a look at that and see if > you can do what you need based on that pci/host branch? Sure, I'll look at that on Monday when I'm back from vacation. Cheers Kishon