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=-9.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 23B11C0044C for ; Wed, 31 Oct 2018 23:24:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E033220847 for ; Wed, 31 Oct 2018 23:24:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="O995AjaU" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E033220847 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730298AbeKAIZA (ORCPT ); Thu, 1 Nov 2018 04:25:00 -0400 Received: from mail.kernel.org ([198.145.29.99]:33528 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731218AbeKAIKo (ORCPT ); Thu, 1 Nov 2018 04:10:44 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id EC15C2085A; Wed, 31 Oct 2018 23:10:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1541027432; bh=Prz2yyqbfMWvbBTgphACYPuwkila1hfGa4sSxSaeUTw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=O995AjaUIsqEy/v3khFJjMYVe4H2OwwQYIjKoeIBu4WJ670l1EJUdn5qAt74bikxL VOJYajFnEDBwBNLf0YIdqcW9vCFPShCFFpy/HosthmavpFrDrJpJ+8URzgeFjcAg6Y ncdYosByQUKTOINlf9S0u/M1o/R5DEt+JpJ7Wq8U= From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Honghui Zhang , Lorenzo Pieralisi , Sasha Levin Subject: [PATCH AUTOSEL 4.14 49/73] PCI: mediatek: Fix mtk_pcie_find_port() endpoint/port matching logic Date: Wed, 31 Oct 2018 19:09:24 -0400 Message-Id: <20181031230948.29203-49-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181031230948.29203-1-sashal@kernel.org> References: <20181031230948.29203-1-sashal@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Honghui Zhang [ Upstream commit 074d6f32689ce05a084b6fa3db38445745bf11cc ] The Mediatek's host controller has two slots, each with its own control registers. The host driver needs to identify what slot is connected to what port in order to access the device's configuration space. Current code retrieving slot connected to a given endpoint device. Assuming each slot is connected to one endpoint device as below: host bridge bus 0 --> __________|_______ | | | | slot 0 slot 1 bus 1 -->| bus 2 --> | | | EP 0 EP 1 During PCI enumeration, system software will scan all the PCI devices on every bus starting from devfn 0. Using PCI_SLOT(devfn) for matching an endpoint to its slot is erroneous in that the devfn does not contain the hierarchical bus numbering in it. In order to match an endpoint with its slot (and related port), the PCI tree must be walked up to the root bus (where the root ports are situated) and then the PCI_SLOT(devfn) matching logic can be correctly applied for matching. This patch fixes the mtk_pcie_find_port() slot matching logic by adding appropriate PCI tree walking code to retrieve the slot/port a given endpoint is connected to. Signed-off-by: Honghui Zhang [lorenzo.pieralisi@arm.com: rewrote the commit log] Signed-off-by: Lorenzo Pieralisi Acked-by: Ryder Lee Signed-off-by: Sasha Levin --- drivers/pci/host/pcie-mediatek.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/pci/host/pcie-mediatek.c b/drivers/pci/host/pcie-mediatek.c index db93efdf1d63..c896bb9ef968 100644 --- a/drivers/pci/host/pcie-mediatek.c +++ b/drivers/pci/host/pcie-mediatek.c @@ -333,6 +333,17 @@ static struct mtk_pcie_port *mtk_pcie_find_port(struct pci_bus *bus, { struct mtk_pcie *pcie = bus->sysdata; struct mtk_pcie_port *port; + struct pci_dev *dev = NULL; + + /* + * Walk the bus hierarchy to get the devfn value + * of the port in the root bus. + */ + while (bus && bus->number) { + dev = bus->self; + bus = dev->bus; + devfn = dev->devfn; + } list_for_each_entry(port, &pcie->ports, list) if (port->slot == PCI_SLOT(devfn)) -- 2.17.1