From patchwork Tue May 22 17:05:08 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ray Jui X-Patchwork-Id: 10419215 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.web.codeaurora.org (Postfix) with ESMTP id EB5A5600CC for ; Tue, 22 May 2018 17:06:00 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DCCA728FE3 for ; Tue, 22 May 2018 17:06:00 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D1B3E28FFD; Tue, 22 May 2018 17:06:00 +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=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=unavailable 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 6EF8C29005 for ; Tue, 22 May 2018 17:06:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751821AbeEVRFd (ORCPT ); Tue, 22 May 2018 13:05:33 -0400 Received: from mail-qk0-f195.google.com ([209.85.220.195]:33286 "EHLO mail-qk0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751411AbeEVRF2 (ORCPT ); Tue, 22 May 2018 13:05:28 -0400 Received: by mail-qk0-f195.google.com with SMTP id s12-v6so5482094qke.0 for ; Tue, 22 May 2018 10:05:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=broadcom.com; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=+tdNq8kbvgKUQ6MluZJifHs9BP48noQZ/KT4ha6zMSQ=; b=cf3MDSSprnCDaWv07u1HITsk201v92MtxQYPOqhTHWqJQhqCZj2Kiabmjb7GRUVkSZ FfsnWL83/knfyrS4KGb04/4dBUzuzMGv+SSjgJFUx25P5gIhaIftGY6eCshHH7gEntvu Ecya97rCVpPMsN8jcH0yngCncqL22hu4bkdF4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=+tdNq8kbvgKUQ6MluZJifHs9BP48noQZ/KT4ha6zMSQ=; b=SJA3y9ZtAzXKL4Rhs5HgXVHlWMtc/scAVf1W7aBlo41dHmEP0iBEnpm4zjwdfGwzWD k1d4vcnkH0XtpsLyQ6WaQx+aUf71YFykD0qF2iyCDalInFCbAMdO7ALixw6ZQ3jFmAFa 90f+1gPVs79jeVLveJhg0xWHEtvmq1UMH77XQCkqrjeOgKNuBhHt2A6EKUlb++9iPzqr ttqt8Pju4BjLOxlwYHvuZ5EoMhDmO8XAmtvXzJPc5AQhq/BW3t9w76hpWzgnlSMzPDJN 3qdhiBfJJDw0OOPywa+R2EOoyculTPXTYJ2W+MMBEmuAo4gO8IZUPm3BaI3k0yTW1KSp xkmg== X-Gm-Message-State: ALKqPwfBh+03Z0P8WwPmDKapE7bC23S8uAXDEid71/f7IrL8pAjHIhSs nfpZGThTojrNa15s8NMNFtlkDg== X-Google-Smtp-Source: AB8JxZp2igxos+FydE0Hfb1JCH4CDTdYtryqDQHjZGABvvv/X1wAoFX0ErC2KGySs8D6YSXGUxzKFQ== X-Received: by 2002:a37:5607:: with SMTP id k7-v6mr21828391qkb.53.1527008727437; Tue, 22 May 2018 10:05:27 -0700 (PDT) Received: from lbrmn-lnxub44-1.ric.broadcom.com ([192.19.228.250]) by smtp.gmail.com with ESMTPSA id w12-v6sm13336301qtb.80.2018.05.22.10.05.25 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 22 May 2018 10:05:26 -0700 (PDT) From: Ray Jui To: Lorenzo Pieralisi , Bjorn Helgaas Cc: Bjorn Helgaas , linux-kernel@vger.kernel.org, bcm-kernel-feedback-list@broadcom.com, linux-pci@vger.kernel.org, Ray Jui Subject: [PATCH 1/2] PCI: iproc: Reject unconfigured physical functions from PAXC Date: Tue, 22 May 2018 10:05:08 -0700 Message-Id: <1527008709-20786-2-git-send-email-ray.jui@broadcom.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1527008709-20786-1-git-send-email-ray.jui@broadcom.com> References: <1527008709-20786-1-git-send-email-ray.jui@broadcom.com> 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 PAXC is an emulated PCIe root complex internally in various Broadcom based SoCs. PAXC internally connects to the embedded network processor within these SoCs, with the embedeed network processor exposed as an endpoint device The number of physical functions from the embedded network processor that can be accessed depend on the firmware configuration. Unfortunately, due to an ASIC bug, unconfigured physical functions cannot be properly hidden from the root complex during enumerattion. As a result, config write access to these unconfigured physical functions during enumeration will cause a bus lock up on the embedded network processor Fortunately, these unconfigured physical functions contain a very specific, staled PCIe device ID 0x168e. By making use of this device ID, one is able to terminate the enumeration early in the vendor/device ID config read Signed-off-by: Ray Jui Reviewed-by: Scott Branden --- drivers/pci/host/pcie-iproc.c | 26 +++++++++++++++++++++++++- drivers/pci/host/pcie-iproc.h | 5 +++++ 2 files changed, 30 insertions(+), 1 deletion(-) diff --git a/drivers/pci/host/pcie-iproc.c b/drivers/pci/host/pcie-iproc.c index b906d80..b1d8c60 100644 --- a/drivers/pci/host/pcie-iproc.c +++ b/drivers/pci/host/pcie-iproc.c @@ -529,6 +529,25 @@ static int iproc_pcie_config_read(struct pci_bus *bus, unsigned int devfn, if (size <= 2) *val = (data >> (8 * (where & 3))) & ((1 << (size * 8)) - 1); + /* + * For PAXC and PAXCv2, the total number of PFs that one can enumerate + * depends on the firmware configuration. Unfortunately, due to an ASIC + * bug, unconfigured PFs cannot be properly hidden from the root + * complex. As a result, write access to these PFs will cause bus lock + * up on the embedded processor + * + * Since all unconfigured PFs are left with an incorrect, staled device + * ID of 0x168e (PCI_DEVICE_ID_NX2_57810), we try to catch those access + * early here and reject them all + */ +#define DEVICE_ID_MASK 0xffff0000 +#define DEVICE_ID_SHIFT 16 + if (pcie->rej_unconfig_pf && + (where & CFG_ADDR_REG_NUM_MASK) == PCI_VENDOR_ID) + if ((*val & DEVICE_ID_MASK) == + (PCI_DEVICE_ID_NX2_57810 << DEVICE_ID_SHIFT)) + return PCIBIOS_FUNC_NOT_SUPPORTED; + return PCIBIOS_SUCCESSFUL; } @@ -628,7 +647,7 @@ static int iproc_pcie_config_read32(struct pci_bus *bus, unsigned int devfn, struct iproc_pcie *pcie = iproc_data(bus); iproc_pcie_apb_err_disable(bus, true); - if (pcie->type == IPROC_PCIE_PAXB_V2) + if (pcie->iproc_cfg_read) ret = iproc_pcie_config_read(bus, devfn, where, size, val); else ret = pci_generic_config_read32(bus, devfn, where, size, val); @@ -1283,6 +1302,7 @@ static int iproc_pcie_rev_init(struct iproc_pcie *pcie) break; case IPROC_PCIE_PAXB: regs = iproc_pcie_reg_paxb; + pcie->iproc_cfg_read = true; pcie->has_apb_err_disable = true; if (pcie->need_ob_cfg) { pcie->ob_map = paxb_ob_map; @@ -1305,10 +1325,14 @@ static int iproc_pcie_rev_init(struct iproc_pcie *pcie) case IPROC_PCIE_PAXC: regs = iproc_pcie_reg_paxc; pcie->ep_is_internal = true; + pcie->iproc_cfg_read = true; + pcie->rej_unconfig_pf = true; break; case IPROC_PCIE_PAXC_V2: regs = iproc_pcie_reg_paxc_v2; pcie->ep_is_internal = true; + pcie->iproc_cfg_read = true; + pcie->rej_unconfig_pf = true; pcie->need_msi_steer = true; break; default: diff --git a/drivers/pci/host/pcie-iproc.h b/drivers/pci/host/pcie-iproc.h index 814b600..67081cb 100644 --- a/drivers/pci/host/pcie-iproc.h +++ b/drivers/pci/host/pcie-iproc.h @@ -58,6 +58,9 @@ struct iproc_msi; * @phy: optional PHY device that controls the Serdes * @map_irq: function callback to map interrupts * @ep_is_internal: indicates an internal emulated endpoint device is connected + * @iproc_cfg_read: indicates the iProc config read function should be used + * @rej_unconfig_pf: indicates the root complex needs to detect and reject + * enumeration against unconfigured physical functions emulated in the ASIC * @has_apb_err_disable: indicates the controller can be configured to prevent * unsupported request from being forwarded as an APB bus error * @@ -84,6 +87,8 @@ struct iproc_pcie { struct phy *phy; int (*map_irq)(const struct pci_dev *, u8, u8); bool ep_is_internal; + bool iproc_cfg_read; + bool rej_unconfig_pf; bool has_apb_err_disable; bool need_ob_cfg;