From patchwork Sun Aug 27 17:40:49 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sinan Kaya X-Patchwork-Id: 9923987 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 2083D604D9 for ; Sun, 27 Aug 2017 17:42:47 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0E9512863E for ; Sun, 27 Aug 2017 17:42:47 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id EF3242864A; Sun, 27 Aug 2017 17:42:46 +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=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID 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 7B04D28623 for ; Sun, 27 Aug 2017 17:42:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751302AbdH0Rlp (ORCPT ); Sun, 27 Aug 2017 13:41:45 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:42596 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751263AbdH0RlD (ORCPT ); Sun, 27 Aug 2017 13:41:03 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id B343B6072E; Sun, 27 Aug 2017 17:41:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1503855662; bh=TLw3rtfuszzlvFKE3SUS/SjOdbkWChwBYPp1zwM6gZo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lS8cOqGfUkN5jWbF077SgE2aeYcRs0VXBoO2/HGATdebgCzuLSgF0kfPZ52AaRJ23 KLhNh/c2nCZDa+IvGhhIgcq1fd1nHa8oW2D8EPUgmwH1lKJtVvkz9t3ukxFcuw93OQ b6gfchH5fyaRCKd5OY0jihQvr2ikhgxgtjUJxQBQ= Received: from drakthul.qualcomm.com (global_nat1_iad_fw.qualcomm.com [129.46.232.65]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: okaya@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id 4443860722; Sun, 27 Aug 2017 17:41:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1503855662; bh=TLw3rtfuszzlvFKE3SUS/SjOdbkWChwBYPp1zwM6gZo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lS8cOqGfUkN5jWbF077SgE2aeYcRs0VXBoO2/HGATdebgCzuLSgF0kfPZ52AaRJ23 KLhNh/c2nCZDa+IvGhhIgcq1fd1nHa8oW2D8EPUgmwH1lKJtVvkz9t3ukxFcuw93OQ b6gfchH5fyaRCKd5OY0jihQvr2ikhgxgtjUJxQBQ= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 4443860722 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=okaya@codeaurora.org From: Sinan Kaya To: linux-pci@vger.kernel.org, timur@codeaurora.org, alex.williamson@redhat.com Cc: linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Sinan Kaya , Bjorn Helgaas , linux-kernel@vger.kernel.org Subject: [PATCH V13 2/4] PCI: Factor out pci_bus_wait_crs() Date: Sun, 27 Aug 2017 13:40:49 -0400 Message-Id: <1503855651-17409-2-git-send-email-okaya@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1503855651-17409-1-git-send-email-okaya@codeaurora.org> References: <1503855651-17409-1-git-send-email-okaya@codeaurora.org> 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 Configuration Request Retry Status (CRS) was previously hidden inside pci_bus_read_dev_vendor_id(). We want to add support for CRS in other situations, such as waiting for a device to become ready after a Function Level Reset. Move CRS handling into pci_bus_wait_crs() so it can be called from other places and also introduce pci_bus_crs_visibility_pending() to determine when we should wait. Signed-off-by: Sinan Kaya --- drivers/pci/probe.c | 52 ++++++++++++++++++++++++++++++++++------------------ 1 file changed, 34 insertions(+), 18 deletions(-) diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 2849e0e..d834a20 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1824,30 +1824,29 @@ struct pci_dev *pci_alloc_dev(struct pci_bus *bus) } EXPORT_SYMBOL(pci_alloc_dev); -bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l, - int crs_timeout) +static inline bool pci_bus_crs_visibility_pending(u32 l) +{ + return (l & 0xffff) == 0x0001; +} + +static bool pci_bus_wait_crs(struct pci_bus *bus, int devfn, u32 l, + int timeout) { int delay = 1; - if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l)) - return false; + if ((l & 0xffff) != 0x0001) + return true; /* not a CRS completion */ - /* some broken boards return 0 or ~0 if a slot is empty: */ - if (*l == 0xffffffff || *l == 0x00000000 || - *l == 0x0000ffff || *l == 0xffff0000) - return false; + if (!timeout) + return false; /* CRS, but caller doesn't want to wait */ /* - * Configuration Request Retry Status. Some root ports return the - * actual device ID instead of the synthetic ID (0xFFFF) required - * by the PCIe spec. Ignore the device ID and only check for - * (vendor id == 1). + * We got the reserved Vendor ID that indicates a completion with + * Configuration Request Retry Status (CRS). Retry until we get a + * valid Vendor ID or we time out. */ - while ((*l & 0xffff) == 0x0001) { - if (!crs_timeout) - return false; - - if (delay > crs_timeout) { + while ((l & 0xffff) == 0x0001) { + if (delay > timeout) { printk(KERN_WARNING "pci %04x:%02x:%02x.%d: not responding\n", pci_domain_nr(bus), bus->number, PCI_SLOT(devfn), PCI_FUNC(devfn)); @@ -1857,12 +1856,29 @@ bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l, msleep(delay); delay *= 2; - if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l)) + if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, &l)) return false; } return true; } + +bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l, + int timeout) +{ + if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l)) + return false; + + /* some broken boards return 0 or ~0 if a slot is empty: */ + if (*l == 0xffffffff || *l == 0x00000000 || + *l == 0x0000ffff || *l == 0xffff0000) + return false; + + if (pci_bus_crs_visibility_pending(*l)) + return pci_bus_wait_crs(bus, devfn, *l, timeout); + + return true; +} EXPORT_SYMBOL(pci_bus_read_dev_vendor_id); /*