From patchwork Thu Mar 9 07:57:25 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kishon Vijay Abraham I X-Patchwork-Id: 95079 Delivered-To: patch@linaro.org Received: by 10.140.82.71 with SMTP id g65csp246566qgd; Thu, 9 Mar 2017 00:03:46 -0800 (PST) X-Received: by 10.98.220.200 with SMTP id c69mr12493626pfl.60.1489046626720; Thu, 09 Mar 2017 00:03:46 -0800 (PST) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id v35si5705187pgn.161.2017.03.09.00.03.46; Thu, 09 Mar 2017 00:03:46 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-omap-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=neutral (body hash did not verify) header.i=@ti.com; spf=pass (google.com: best guess record for domain of linux-omap-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-omap-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=ti.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752797AbdCIIDZ (ORCPT + 4 others); Thu, 9 Mar 2017 03:03:25 -0500 Received: from fllnx209.ext.ti.com ([198.47.19.16]:59339 "EHLO fllnx209.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753702AbdCIIBE (ORCPT ); Thu, 9 Mar 2017 03:01:04 -0500 Received: from dflxv15.itg.ti.com ([128.247.5.124]) by fllnx209.ext.ti.com (8.15.1/8.15.1) with ESMTP id v297wYRT024441; Thu, 9 Mar 2017 01:58:34 -0600 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ti.com; s=ti-com-17Q1; t=1489046314; bh=HPX/3ulFYXFkhfgQjLMgom1g9y96DiCwjgAO1DaZhNs=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=L12XkP70DK0IhYfDfgIqAOmfzHL0Nvij1qlNUn1Vqbt4L5nlXSHhd5Ads2d6/zZfX 2lFxDBfx+HekQuYxZTE6bf2WbJyrIX2kHRSVe3R55eivbYdkeZA1L1mdSya5bBDBMF ahOq9tKNbPUTZfULMiyn69p63Ho+TdWPbx1YJxeg= Received: from DLEE71.ent.ti.com (dlee71.ent.ti.com [157.170.170.114]) by dflxv15.itg.ti.com (8.14.3/8.13.8) with ESMTP id v297wTNG020260; Thu, 9 Mar 2017 01:58:29 -0600 Received: from dflp32.itg.ti.com (10.64.6.15) by DLEE71.ent.ti.com (157.170.170.114) with Microsoft SMTP Server id 14.3.294.0; Thu, 9 Mar 2017 01:58:28 -0600 Received: from a0393678ub.india.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by dflp32.itg.ti.com (8.14.3/8.13.8) with ESMTP id v297vZPC014250; Thu, 9 Mar 2017 01:58:26 -0600 From: Kishon Vijay Abraham I To: Bjorn Helgaas , Joao Pinto , , , , , , CC: , , Subject: [PATCH v3 14/23] PCI: dwc: dra7xx: Workaround for errata id i870 Date: Thu, 9 Mar 2017 13:27:25 +0530 Message-ID: <1489046254-19919-15-git-send-email-kishon@ti.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1489046254-19919-1-git-send-email-kishon@ti.com> References: <1489046254-19919-1-git-send-email-kishon@ti.com> MIME-Version: 1.0 Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org According to errata i870, access to the PCIe slave port that are not 32-bit aligned will result in incorrect mapping to TLP Address and Byte enable fields. Accessing non 32-bit aligned data causes incorrect data in the target buffer if memcpy is used. Implement the workaround for this errata here. Signed-off-by: Kishon Vijay Abraham I --- drivers/pci/dwc/pci-dra7xx.c | 53 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/drivers/pci/dwc/pci-dra7xx.c b/drivers/pci/dwc/pci-dra7xx.c index 1cd5c2b..71783a6 100644 --- a/drivers/pci/dwc/pci-dra7xx.c +++ b/drivers/pci/dwc/pci-dra7xx.c @@ -26,6 +26,8 @@ #include #include #include +#include +#include #include "pcie-designware.h" @@ -528,6 +530,51 @@ static int dra7xx_pcie_enable_phy(struct dra7xx_pcie *dra7xx) {}, }; +/* + * dra7xx_pcie_ep_unaligned_memaccess: workaround for AM572x/AM571x Errata i870 + * @dra7xx: the dra7xx device where the workaround should be applied + * + * Access to the PCIe slave port that are not 32-bit aligned will result + * in incorrect mapping to TLP Address and Byte enable fields. Therefore, + * byte and half-word accesses are not possible to byte offset 0x1, 0x2, or + * 0x3. + * + * To avoid this issue set PCIE_SS1_AXI2OCP_LEGACY_MODE_ENABLE to 1. + */ +static int dra7xx_pcie_ep_unaligned_memaccess(struct device *dev) +{ + int ret; + struct device_node *np = dev->of_node; + struct regmap *regmap; + unsigned int reg; + unsigned int field; + + regmap = syscon_regmap_lookup_by_phandle(np, + "ti,syscon-unaligned-access"); + if (IS_ERR(regmap)) { + dev_dbg(dev, "can't get ti,syscon-unaligned-access\n"); + return -EINVAL; + } + + if (of_property_read_u32_index(np, "ti,syscon-unaligned-access", 1, + ®)) { + dev_err(dev, "couldn't get legacy mode register offset\n"); + return -EINVAL; + } + + if (of_property_read_u32_index(np, "ti,syscon-unaligned-access", 2, + &field)) { + dev_err(dev, "can't get bit field for setting legacy mode\n"); + return -EINVAL; + } + + ret = regmap_update_bits(regmap, reg, field, field); + if (ret) + dev_err(dev, "failed to enable unaligned access\n"); + + return ret; +} + static int __init dra7xx_pcie_probe(struct platform_device *pdev) { u32 reg; @@ -637,6 +684,7 @@ static int __init dra7xx_pcie_probe(struct platform_device *pdev) case DW_PCIE_RC_TYPE: dra7xx_pcie_writel(dra7xx, PCIECTRL_TI_CONF_DEVICE_TYPE, DEVICE_TYPE_RC); + ret = dra7xx_add_pcie_port(dra7xx, pdev); if (ret < 0) goto err_gpio; @@ -644,6 +692,11 @@ static int __init dra7xx_pcie_probe(struct platform_device *pdev) case DW_PCIE_EP_TYPE: dra7xx_pcie_writel(dra7xx, PCIECTRL_TI_CONF_DEVICE_TYPE, DEVICE_TYPE_EP); + + ret = dra7xx_pcie_ep_unaligned_memaccess(dev); + if (ret) + goto err_gpio; + ret = dra7xx_add_pcie_ep(dra7xx, pdev); if (ret < 0) goto err_gpio;