From patchwork Fri Sep 28 10:04:32 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Honghui Zhang X-Patchwork-Id: 10619303 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A41531750 for ; Fri, 28 Sep 2018 10:04:52 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 97D4E2AF15 for ; Fri, 28 Sep 2018 10:04:52 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8B4702B213; Fri, 28 Sep 2018 10:04:52 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI,UNPARSEABLE_RELAY autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 328122B209 for ; Fri, 28 Sep 2018 10:04:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729292AbeI1Q1t (ORCPT ); Fri, 28 Sep 2018 12:27:49 -0400 Received: from mailgw01.mediatek.com ([210.61.82.183]:45099 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1729268AbeI1Q1s (ORCPT ); Fri, 28 Sep 2018 12:27:48 -0400 X-UUID: fdd5fcdeb3d944f9bf6fef344bfe3795-20180928 Received: from mtkexhb02.mediatek.inc [(172.21.101.103)] by mailgw01.mediatek.com (envelope-from ) (mhqrelay.mediatek.com ESMTP with TLS) with ESMTP id 2050651582; Fri, 28 Sep 2018 18:04:45 +0800 Received: from MTKCAS06.mediatek.inc (172.21.101.30) by mtkmbs08n2.mediatek.inc (172.21.101.56) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Fri, 28 Sep 2018 18:04:43 +0800 Received: from localhost.localdomain (10.17.3.153) by MTKCAS06.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1395.4 via Frontend Transport; Fri, 28 Sep 2018 18:04:42 +0800 From: To: , , , , , , CC: , , , , , , , , , Subject: [PATCH v5 1/9] PCI: mediatek: Using slot's devfn for compare to fix mtk_pcie_find_port logic Date: Fri, 28 Sep 2018 18:04:32 +0800 Message-ID: <1538129080-8206-2-git-send-email-honghui.zhang@mediatek.com> X-Mailer: git-send-email 2.6.4 In-Reply-To: <1538129080-8206-1-git-send-email-honghui.zhang@mediatek.com> References: <1538129080-8206-1-git-send-email-honghui.zhang@mediatek.com> MIME-Version: 1.0 X-TM-SNTS-SMTP: 5855F8BC4DEC6CD93D2617F41CDD3F62E583445DEB4E583805C1A9F4FD3E039E2000:8 X-MTK: N Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Honghui Zhang The Mediatek's host controller has two slots, each with it's own control registers. The host driver need to identify which slot was connected in order to access the device's configuration space. There's problem for current host driver to find out which slot was connected to for a given EP device. Assuming each slot have connect with one EP 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 device starting from devfn 0. So it will get the proper port for slot0 and slot1 device when using PCI_SLOT(devfn) for match. But it will get the wrong slot for EP1: The devfn will be start from 0 when scanning EP1 behind slot1, it will get port0 since the PCI_SLOT(EP1) is match for port0's slot value. So the host driver should not using EP's devfn but the slot's devfn(the slot which EP was connected to) for match. This patch fix the mtk_pcie_find_port's logic by using the slot's devfn for match if finding device connected to the subordinate bus. Signed-off-by: Honghui Zhang --- drivers/pci/controller/pcie-mediatek.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/drivers/pci/controller/pcie-mediatek.c b/drivers/pci/controller/pcie-mediatek.c index 9999dae..264e03f 100644 --- a/drivers/pci/controller/pcie-mediatek.c +++ b/drivers/pci/controller/pcie-mediatek.c @@ -337,10 +337,25 @@ 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; + } + + list_for_each_entry(port, &pcie->ports, list) { + /* Using slot's devfn to compare for subordinary bus. */ + if (dev) + devfn = dev->devfn; - list_for_each_entry(port, &pcie->ports, list) if (port->slot == PCI_SLOT(devfn)) return port; + } return NULL; }