From patchwork Thu Mar 25 09:00:26 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Kishon Vijay Abraham I X-Patchwork-Id: 409009 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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, 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 38939C433E2 for ; Thu, 25 Mar 2021 09:01:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E39D461A27 for ; Thu, 25 Mar 2021 09:01:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229929AbhCYJBJ (ORCPT ); Thu, 25 Mar 2021 05:01:09 -0400 Received: from fllv0016.ext.ti.com ([198.47.19.142]:49494 "EHLO fllv0016.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229889AbhCYJBF (ORCPT ); Thu, 25 Mar 2021 05:01:05 -0400 Received: from fllv0034.itg.ti.com ([10.64.40.246]) by fllv0016.ext.ti.com (8.15.2/8.15.2) with ESMTP id 12P90uB2035081; Thu, 25 Mar 2021 04:00:56 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1616662856; bh=ExpgZ6jri5aKrfzIk/qutKm65aR1bRdGd7julUa6edQ=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=PCDVgU9BlNPXt4roC7SMP0y2qNFHUtwO7Zqpx2XoOlC4vYmnBFYdo5jNLjKYFT6LT UeKz2ONOw8oL8dD5GxeNcedIMcLQx/wIb/AgOaW9ywUB6EVZQvnMW+qOt8gAkrnl8Y uA7v5PdvFiyw52lVYrlTawMKGIGJwDrel0lGuI1U= Received: from DFLE105.ent.ti.com (dfle105.ent.ti.com [10.64.6.26]) by fllv0034.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 12P90ue3008917 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Thu, 25 Mar 2021 04:00:56 -0500 Received: from DFLE104.ent.ti.com (10.64.6.25) by DFLE105.ent.ti.com (10.64.6.26) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Thu, 25 Mar 2021 04:00:56 -0500 Received: from lelv0326.itg.ti.com (10.180.67.84) by DFLE104.ent.ti.com (10.64.6.25) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2 via Frontend Transport; Thu, 25 Mar 2021 04:00:56 -0500 Received: from a0393678-ssd.dhcp.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by lelv0326.itg.ti.com (8.15.2/8.15.2) with ESMTP id 12P90RkD115556; Thu, 25 Mar 2021 04:00:53 -0500 From: Kishon Vijay Abraham I To: Kishon Vijay Abraham I , Bjorn Helgaas , Rob Herring , Lorenzo Pieralisi , Marc Zyngier CC: , , , , Lokesh Vutla Subject: [PATCH 6/6] PCI: keystone: Add workaround for Errata #i2037 (AM65x SR 1.0) Date: Thu, 25 Mar 2021 14:30:26 +0530 Message-ID: <20210325090026.8843-7-kishon@ti.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210325090026.8843-1-kishon@ti.com> References: <20210325090026.8843-1-kishon@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Errata #i2037 in AM65x/DRA80xM Processors Silicon Revision 1.0 (SPRZ452D–July 2018–Revised December 2019 [1]) mentions when an inbound PCIe TLP spans more than two internal AXI 128-byte bursts, the bus may corrupt the packet payload and the corrupt data may cause associated applications or the processor to hang. The workaround for Errata #i2037 is to limit the maximum read request size and maximum payload size to 128 Bytes. Add workaround for Errata #i2037 here. The errata and workaround is applicable only to AM65x SR 1.0 and later versions of the silicon will have this fixed. [1] -> http://www.ti.com/lit/er/sprz452d/sprz452d.pdf Signed-off-by: Kishon Vijay Abraham I --- drivers/pci/controller/dwc/pci-keystone.c | 42 +++++++++++++++++++++++ 1 file changed, 42 insertions(+) diff --git a/drivers/pci/controller/dwc/pci-keystone.c b/drivers/pci/controller/dwc/pci-keystone.c index 84a25207d0d3..80b6e874199d 100644 --- a/drivers/pci/controller/dwc/pci-keystone.c +++ b/drivers/pci/controller/dwc/pci-keystone.c @@ -35,6 +35,11 @@ #define PCIE_DEVICEID_SHIFT 16 /* Application registers */ +#define PID 0x000 +#define RTL GENMASK(15, 11) +#define RTL_SHIFT 11 +#define AM6_PCI_PG1_RTL_VER 0x15 + #define CMD_STATUS 0x004 #define LTSSM_EN_VAL BIT(0) #define OB_XLAT_EN_VAL BIT(1) @@ -106,6 +111,8 @@ #define to_keystone_pcie(x) dev_get_drvdata((x)->dev) +#define PCI_DEVICE_ID_TI_AM654X 0xb00c + struct ks_pcie_of_data { enum dw_pcie_device_mode mode; const struct dw_pcie_host_ops *host_ops; @@ -619,7 +626,11 @@ static int ks_pcie_start_link(struct dw_pcie *pci) static void ks_pcie_quirk(struct pci_dev *dev) { struct pci_bus *bus = dev->bus; + struct keystone_pcie *ks_pcie; + struct device *bridge_dev; struct pci_dev *bridge; + u32 val; + static const struct pci_device_id rc_pci_devids[] = { { PCI_DEVICE(PCI_VENDOR_ID_TI, PCIE_RC_K2HK), .class = PCI_CLASS_BRIDGE_PCI << 8, .class_mask = ~0, }, @@ -631,6 +642,11 @@ static void ks_pcie_quirk(struct pci_dev *dev) .class = PCI_CLASS_BRIDGE_PCI << 8, .class_mask = ~0, }, { 0, }, }; + static const struct pci_device_id am6_pci_devids[] = { + { PCI_DEVICE(PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_AM654X), + .class = PCI_CLASS_BRIDGE_PCI << 8, .class_mask = ~0, }, + { 0, }, + }; if (pci_is_root_bus(bus)) bridge = dev; @@ -656,6 +672,32 @@ static void ks_pcie_quirk(struct pci_dev *dev) pcie_set_readrq(dev, 256); } } + + /* + * Memory transactions fail with PCI controller in AM654 PG1.0 + * when MRRS is set to more than 128 Bytes. Force the MRRS to + * 128 Bytes in all downstream devices. + */ + if (pci_match_id(am6_pci_devids, bridge)) { + bridge_dev = pci_get_host_bridge_device(dev); + if (!bridge_dev && !bridge_dev->parent) + return; + + ks_pcie = dev_get_drvdata(bridge_dev->parent); + if (!ks_pcie) + return; + + val = ks_pcie_app_readl(ks_pcie, PID); + val &= RTL; + val >>= RTL_SHIFT; + if (val != AM6_PCI_PG1_RTL_VER) + return; + + if (pcie_get_readrq(dev) > 128) { + dev_info(&dev->dev, "limiting MRRS to 128\n"); + pcie_set_readrq(dev, 128); + } + } } DECLARE_PCI_FIXUP_ENABLE(PCI_ANY_ID, PCI_ANY_ID, ks_pcie_quirk);