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 X-Spam-Level: X-Spam-Status: No, score=-11.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7E146C433E7 for ; Wed, 14 Oct 2020 11:13:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3476320878 for ; Wed, 14 Oct 2020 11:13:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730632AbgJNLNU (ORCPT ); Wed, 14 Oct 2020 07:13:20 -0400 Received: from foss.arm.com ([217.140.110.172]:38898 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730016AbgJNLNT (ORCPT ); Wed, 14 Oct 2020 07:13:19 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 2C67D1FB; Wed, 14 Oct 2020 04:13:19 -0700 (PDT) Received: from e121166-lin.cambridge.arm.com (e121166-lin.cambridge.arm.com [10.1.196.255]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 46DCE3F66B; Wed, 14 Oct 2020 04:13:18 -0700 (PDT) Date: Wed, 14 Oct 2020 12:13:12 +0100 From: Lorenzo Pieralisi To: Zhiqiang Hou , robh@kernel.org Cc: linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, bhelgaas@google.com, gustavo.pimentel@synopsys.com Subject: Re: [PATCH] PCI: dwc: Added link up check in map_bus of dw_child_pcie_ops Message-ID: <20201014111312.GA4110@e121166-lin.cambridge.arm.com> References: <20200916054130.8685-1-Zhiqiang.Hou@nxp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200916054130.8685-1-Zhiqiang.Hou@nxp.com> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Wed, Sep 16, 2020 at 01:41:30PM +0800, Zhiqiang Hou wrote: > From: Hou Zhiqiang > > On NXP Layerscape platforms, it results in SError in the > enumeration of the PCIe controller, which is not connecting > with an Endpoint device. And it doesn't make sense to > enumerate the Endpoints when the PCIe link is down. So this > patch added the link up check to avoid to fire configuration > transactions on link down bus. > > [ 0.807773] SError Interrupt on CPU2, code 0xbf000002 -- SError > [ 0.807775] CPU: 2 PID: 1 Comm: swapper/0 Not tainted 5.9.0-rc5-next-20200914-00001-gf965d3ec86fa #67 > [ 0.807776] Hardware name: LS1046A RDB Board (DT) > [ 0.807777] pstate: 20000085 (nzCv daIf -PAN -UAO BTYPE=--) > [ 0.807778] pc : pci_generic_config_read+0x3c/0xe0 > [ 0.807778] lr : pci_generic_config_read+0x24/0xe0 > [ 0.807779] sp : ffff80001003b7b0 > [ 0.807780] x29: ffff80001003b7b0 x28: ffff80001003ba74 > [ 0.807782] x27: ffff000971d96800 x26: ffff00096e77e0a8 > [ 0.807784] x25: ffff80001003b874 x24: ffff80001003b924 > [ 0.807786] x23: 0000000000000004 x22: 0000000000000000 > [ 0.807788] x21: 0000000000000000 x20: ffff80001003b874 > [ 0.807790] x19: 0000000000000004 x18: ffffffffffffffff > [ 0.807791] x17: 00000000000000c0 x16: fffffe0025981840 > [ 0.807793] x15: ffffb94c75b69948 x14: 62203a383634203a > [ 0.807795] x13: 666e6f635f726568 x12: 202c31203d207265 > [ 0.807797] x11: 626d756e3e2d7375 x10: 656877202c307830 > [ 0.807799] x9 : 203d206e66766564 x8 : 0000000000000908 > [ 0.807801] x7 : 0000000000000908 x6 : ffff800010900000 > [ 0.807802] x5 : ffff00096e77e080 x4 : 0000000000000000 > [ 0.807804] x3 : 0000000000000003 x2 : 84fa3440ff7e7000 > [ 0.807806] x1 : 0000000000000000 x0 : ffff800010034000 > [ 0.807808] Kernel panic - not syncing: Asynchronous SError Interrupt > [ 0.807809] CPU: 2 PID: 1 Comm: swapper/0 Not tainted 5.9.0-rc5-next-20200914-00001-gf965d3ec86fa #67 > [ 0.807810] Hardware name: LS1046A RDB Board (DT) > [ 0.807811] Call trace: > [ 0.807812] dump_backtrace+0x0/0x1c0 > [ 0.807813] show_stack+0x18/0x28 > [ 0.807814] dump_stack+0xd8/0x134 > [ 0.807814] panic+0x180/0x398 > [ 0.807815] add_taint+0x0/0xb0 > [ 0.807816] arm64_serror_panic+0x78/0x88 > [ 0.807817] do_serror+0x68/0x180 > [ 0.807818] el1_error+0x84/0x100 > [ 0.807818] pci_generic_config_read+0x3c/0xe0 > [ 0.807819] dw_pcie_rd_other_conf+0x78/0x110 > [ 0.807820] pci_bus_read_config_dword+0x88/0xe8 > [ 0.807821] pci_bus_generic_read_dev_vendor_id+0x30/0x1b0 > [ 0.807822] pci_bus_read_dev_vendor_id+0x4c/0x78 > [ 0.807823] pci_scan_single_device+0x80/0x100 > [ 0.807824] pci_scan_slot+0x38/0x130 > [ 0.807825] pci_scan_child_bus_extend+0x54/0x2a0 > [ 0.807826] pci_scan_child_bus+0x14/0x20 > [ 0.807827] pci_scan_bridge_extend+0x230/0x570 > [ 0.807828] pci_scan_child_bus_extend+0x134/0x2a0 > [ 0.807829] pci_scan_root_bus_bridge+0x64/0xf0 > [ 0.807829] pci_host_probe+0x18/0xc8 > [ 0.807830] dw_pcie_host_init+0x220/0x378 > [ 0.807831] ls_pcie_probe+0x104/0x140 > [ 0.807832] platform_drv_probe+0x54/0xa8 > [ 0.807833] really_probe+0x118/0x3e0 > [ 0.807834] driver_probe_device+0x5c/0xc0 > [ 0.807835] device_driver_attach+0x74/0x80 > [ 0.807835] __driver_attach+0x8c/0xd8 > [ 0.807836] bus_for_each_dev+0x7c/0xd8 > [ 0.807837] driver_attach+0x24/0x30 > [ 0.807838] bus_add_driver+0x154/0x200 > [ 0.807839] driver_register+0x64/0x120 > [ 0.807839] __platform_driver_probe+0x7c/0x148 > [ 0.807840] ls_pcie_driver_init+0x24/0x30 > [ 0.807841] do_one_initcall+0x60/0x1d8 > [ 0.807842] kernel_init_freeable+0x1f4/0x24c > [ 0.807843] kernel_init+0x14/0x118 > [ 0.807843] ret_from_fork+0x10/0x34 > [ 0.807854] SMP: stopping secondary CPUs > [ 0.807855] Kernel Offset: 0x394c64080000 from 0xffff800010000000 > [ 0.807856] PHYS_OFFSET: 0xffff8bfd40000000 > [ 0.807856] CPU features: 0x0240022,21806000 > [ 0.807857] Memory Limit: none > > Fixes: c2b0c098fbd1 ("PCI: dwc: Use generic config accessors") Hi Rob, can I squash this patch into the commit above ? Thanks, Lorenzo > Signed-off-by: Hou Zhiqiang > --- > drivers/pci/controller/dwc/pcie-designware-host.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c > index c01c9d2fb3f9..e82b518430c5 100644 > --- a/drivers/pci/controller/dwc/pcie-designware-host.c > +++ b/drivers/pci/controller/dwc/pcie-designware-host.c > @@ -442,6 +442,9 @@ static void __iomem *dw_pcie_other_conf_map_bus(struct pci_bus *bus, > struct pcie_port *pp = bus->sysdata; > struct dw_pcie *pci = to_dw_pcie_from_pp(pp); > > + if (!dw_pcie_link_up(pci)) > + return NULL; > + > busdev = PCIE_ATU_BUS(bus->number) | PCIE_ATU_DEV(PCI_SLOT(devfn)) | > PCIE_ATU_FUNC(PCI_FUNC(devfn)); > > -- > 2.17.1 >