Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753859AbcKPAa7 (ORCPT ); Tue, 15 Nov 2016 19:30:59 -0500 Received: from mail-ua0-f194.google.com ([209.85.217.194]:36009 "EHLO mail-ua0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751166AbcKPAa6 (ORCPT ); Tue, 15 Nov 2016 19:30:58 -0500 MIME-Version: 1.0 In-Reply-To: References: <20160817195239.10418.7037.stgit@bhelgaas-glaptop2.roam.corp.google.com> <20160817200022.10418.88555.stgit@bhelgaas-glaptop2.roam.corp.google.com> From: Fabio Estevam Date: Tue, 15 Nov 2016 22:30:56 -0200 Message-ID: Subject: Re: [PATCH v6 4/4] PCI: designware: Add iATU Unroll feature To: Tim Harvey Cc: Bjorn Helgaas , Joao Pinto , Jisheng Zhang , Jingoo Han , "linux-kernel@vger.kernel.org" , "linux-pci@vger.kernel.org" , Lucas Stach Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1525 Lines: 34 Hi Tim, On Tue, Nov 15, 2016 at 10:22 PM, Tim Harvey wrote: > Bjorn / Joao, > > This patch (from commit a0601a47053714eecec726aea5ebcd829f817497) is > causing a kernel regression in 4.9. I can no longer boot the kernel on > boards that have a PCIe switch downstream from the IMX6 (ie many of > the Gateworks Ventana boards) unless PCI is enabled in the bootloader > (which is not recommended as that causes PCI link in the kernel to > occasionally fail). This has been fixed in 4.9-rc4 by the following commit: commit 416379f9ebded501eda882e6af0a7aafc1866700 Author: Niklas Cassel Date: Fri Oct 14 23:54:55 2016 +0200 PCI: designware: Check for iATU unroll support after initializing host dw_pcie_iatu_unroll_enabled() reads a dbi_base register. Reading any dbi_base register before pp->ops->host_init has been called causes "imprecise external abort" on platforms like ARTPEC-6, where the PCIe module is disabled at boot and first enabled in pp->ops->host_init. Move dw_pcie_iatu_unroll_enabled() to dw_pcie_setup_rc(), since it is after pp->ops->host_init, but before pp->iatu_unroll_enabled is actually used. Fixes: a0601a470537 ("PCI: designware: Add iATU Unroll feature") Tested-by: James Le Cuirot Signed-off-by: Niklas Cassel Signed-off-by: Bjorn Helgaas Acked-by: Joao Pinto Acked-by: Olof Johansson