From patchwork Mon Feb 25 16:02:26 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Agner X-Patchwork-Id: 1047841 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=agner.ch Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=agner.ch header.i=@agner.ch header.b="frVCc322"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 447RY35200z9s4V for ; Tue, 26 Feb 2019 03:02:31 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727733AbfBYQCa (ORCPT ); Mon, 25 Feb 2019 11:02:30 -0500 Received: from mail.kmu-office.ch ([178.209.48.109]:42632 "EHLO mail.kmu-office.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727731AbfBYQCa (ORCPT ); Mon, 25 Feb 2019 11:02:30 -0500 Received: from trochilidae.toradex.int (unknown [46.140.72.82]) by mail.kmu-office.ch (Postfix) with ESMTPSA id C7B1B5C2A43; Mon, 25 Feb 2019 17:02:27 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=agner.ch; s=dkim; t=1551110548; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type: content-transfer-encoding:content-transfer-encoding:in-reply-to: references; bh=Od0vcagE+sel1qAnIQtN1qWr7LqLM5Dkvt9IwsRmvEE=; b=frVCc322suw1AEVsR/ejKAerlh59Kk6q94AwRND5XEmdf4OzPNmzBBMxxEq0oTPqXOqoHY R/+Hfd13OOnfIxN1TWMD8pm/9aMzWlAQoaqoQoXSDqR6IdLPM4Y6DVGns0mk+l4XD6LlPO L5oH1nUHnDNL94MzzcfhClCdK/CfrDQ= From: Stefan Agner To: lorenzo.pieralisi@arm.com, jingoohan1@gmail.com, gustavo.pimentel@synopsys.com, l.stach@pengutronix.de, tpiepho@impinj.com Cc: leonard.crestez@nxp.com, bhelgaas@google.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Stefan Agner Subject: [PATCH v7] PCI: imx6: limit DBI register length Date: Mon, 25 Feb 2019 17:02:26 +0100 Message-Id: <20190225160226.11924-1-stefan@agner.ch> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Define the length of the DBI registers and limit config space to its length. This makes sure that the kernel does not access registers beyond that point, avoiding the following abort on a i.MX 6Quad: # cat /sys/devices/soc0/soc/1ffc000.pcie/pci0000\:00/0000\:00\:00.0/config [ 100.021433] Unhandled fault: imprecise external abort (0x1406) at 0xb6ea7000 ... [ 100.056423] PC is at dw_pcie_read+0x50/0x84 [ 100.060790] LR is at dw_pcie_rd_own_conf+0x44/0x48 ... Signed-off-by: Stefan Agner --- Changes in v3: - Rebase on pci/dwc Changes in v4: - Rebase on pci/dwc Changes in v5: - Rebased ontop of pci/dwc - Use DBI length of 0x200 Changes in v6: - Use pci_dev.cfg_size mechanism to limit config space (this made patch 1 of previous versions of this patchset obsolete). Changes in v7: - Restrict fixup to Synopsys/0xabcd - Apply cfg_size limitation only if dbi_length is specified drivers/pci/controller/dwc/pci-imx6.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c index aaa9489e2140..4317d2fffb67 100644 --- a/drivers/pci/controller/dwc/pci-imx6.c +++ b/drivers/pci/controller/dwc/pci-imx6.c @@ -56,6 +56,7 @@ enum imx6_pcie_variants { struct imx6_pcie_drvdata { enum imx6_pcie_variants variant; u32 flags; + int dbi_length; }; struct imx6_pcie { @@ -912,6 +913,25 @@ static const struct dw_pcie_ops dw_pcie_ops = { /* No special ops needed, but pcie-designware still expects this struct */ }; +static void imx6_pcie_quirk(struct pci_dev *dev) +{ + struct pci_bus *bus = dev->bus; + struct pcie_port *pp = bus->sysdata; + + if (bus->number == pp->root_bus_nr) { + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci); + + /* + * Limit config length to avoid the kernel reading beyond + * the register set and causing an abort on i.MX 6Quad + */ + if (imx6_pcie->drvdata->dbi_length) + dev->cfg_size = imx6_pcie->drvdata->dbi_length; + } +} +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_SYNOPSYS, 0xabcd, imx6_pcie_quirk); + #ifdef CONFIG_PM_SLEEP static void imx6_pcie_ltssm_disable(struct device *dev) { @@ -1242,6 +1262,7 @@ static const struct imx6_pcie_drvdata drvdata[] = { .variant = IMX6Q, .flags = IMX6_PCIE_FLAG_IMX6_PHY | IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE, + .dbi_length = 0x200, }, [IMX6SX] = { .variant = IMX6SX,