From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D1973CDB483 for ; Wed, 18 Oct 2023 16:36:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230345AbjJRQgi (ORCPT ); Wed, 18 Oct 2023 12:36:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46520 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229537AbjJRQgg (ORCPT ); Wed, 18 Oct 2023 12:36:36 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3953A113; Wed, 18 Oct 2023 09:36:34 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A14D7C433C7; Wed, 18 Oct 2023 16:36:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1697646993; bh=uN4FTt1WJfID/Mn+71JQqnF+ueyE2WBjOZDWcTg9Tt8=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=dTDtv7a+6jAyDRbZJ7t4ZZEJmkadDCEdEF3hYZtwVRGW+h3m48nUYLh0r5cCTkiLu ep0o48YxHgLr85xuKCozOBVkzxOffLao5QQon8j10wlUGT53uzZY4NeZSbwfviiVig TboNmRsdZRX2Vd16I77OC9tW/7Z9t2/yIRFlZR7JV2x7pSsM7PyfssILKI/5ONYYeI YgO71HUb03rz2fS/3Bt0wAo+rG/uGIV/4WfvhHipzFjOd7fydVFRLUNzEDTcIcPt1v OoiHhAOX5ulw82X9vKHeIJHeJz+J1AEXZQPKU4G5GUkB1LEV6hTMExT1qiZj/O6Eom 4lwYlCHYPWdqA== Date: Wed, 18 Oct 2023 11:36:32 -0500 From: Bjorn Helgaas To: Siddharth Vadapalli Cc: lpieralisi@kernel.org, robh@kernel.org, kw@linux.com, bhelgaas@google.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, r-gunasekaran@ti.com, srk@ti.com, Serge Semin Subject: Re: [PATCH v2] PCI: keystone: Fix ks_pcie_v3_65_add_bus() for AM654x SoC Message-ID: <20231018163632.GA1364574@bhelgaas> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20231018075038.2740534-1-s-vadapalli@ti.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [+cc Serge (please cc people who have commented on previous revisions)] On Wed, Oct 18, 2023 at 01:20:38PM +0530, Siddharth Vadapalli wrote: > The ks_pcie_v3_65_add_bus() member of "ks_pcie_ops" was added for > platforms using DW PCIe IP-core version 3.65a. The AM654x SoC uses > DW PCIe IP-core version 4.90a and ks_pcie_v3_65_add_bus() is not > applicable to it. > > The commit which added support for the AM654x SoC has reused majority > of the functions with the help of the "is_am6" flag to handle AM654x > separately where applicable. Thus, make use of the "is_am6" flag and > change ks_pcie_v3_65_add_bus() to no-op for AM654x SoC. > > Fixes: 18b0415bc802 ("PCI: keystone: Add support for PCIe RC in AM654x Platforms") > Signed-off-by: Siddharth Vadapalli > --- > Hello, > > This patch is based on linux-next tagged next-20231018. > > The v1 of this patch is at: > https://lore.kernel.org/r/20231011123451.34827-1-s-vadapalli@ti.com/ > > While there are a lot of changes since v1 and this patch could have been > posted as a v1 patch itself, I decided to post it as the v2 of the patch > mentioned above since it aims to address the issue described by the v1 > patch and is similar in that sense. However, the solution to the issue > described in the v1 patch appears to be completely different from what > was implemented in the v1 patch. Thus, the commit message and subject of > this patch have been modified accordingly. > > Changes since v1: > - Updated patch subject and commit message. > - Determined that issue is not with the absence of Link as mentioned in > v1 patch. Even with Link up and endpoint device connected, if > ks_pcie_v3_65_add_bus() is invoked and executed, all reads to the > MSI-X offsets return 0xffffffff when pcieport driver attempts to setup > AER and PME services. The all Fs return value indicates that the MSI-X > configuration is failing even if Endpoint device is connected. This is > because the ks_pcie_v3_65_add_bus() function is not applicable to the > AM654x SoC which uses DW PCIe IP-core version 4.90a. Thanks for verifying that this doesn't actually depend on whether the link is up. I think that means we should be able to get rid of the ks_pcie_v3_65_add_bus() callback altogether and instead do this along with the rest of the Root Port init. > drivers/pci/controller/dwc/pci-keystone.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/pci/controller/dwc/pci-keystone.c b/drivers/pci/controller/dwc/pci-keystone.c > index 0def919f89fa..3abd59335574 100644 > --- a/drivers/pci/controller/dwc/pci-keystone.c > +++ b/drivers/pci/controller/dwc/pci-keystone.c > @@ -459,7 +459,7 @@ static int ks_pcie_v3_65_add_bus(struct pci_bus *bus) > struct dw_pcie *pci = to_dw_pcie_from_pp(pp); > struct keystone_pcie *ks_pcie = to_keystone_pcie(pci); > > - if (!pci_is_root_bus(bus)) > + if (!pci_is_root_bus(bus) || ks_pcie->is_am6) > return 0; > > /* Configure and set up BAR0 */ > -- > 2.34.1 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel