From patchwork Tue Jun 17 14:31:20 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Timothy Pearson X-Patchwork-Id: 897579 Received: from raptorengineering.com (mail.raptorengineering.com [23.155.224.40]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2182516C850; Tue, 17 Jun 2025 14:31:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=23.155.224.40 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750170685; cv=none; b=a7Zffg4Cnbr31rfsBHWPxR5ncLV10XpMZYXzJAteg6mF1Ncb7NcJKubfwrlfGH71bzcnde0AmUkq/QLhy+A8uRZ+NK9yxFyYPJEkzrt0ZqS+GnV/4iiQtsaB+NA5NjZh/pRNMimVzG13rtXiGtPEoypsE2kVNkQoJAR9SQY7/D4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750170685; c=relaxed/simple; bh=fjblYqco9O2pK2/UG66z+ix0P+/RjiRxHTHn4GLpv6k=; h=Date:From:To:Cc:Message-ID:Subject:MIME-Version:Content-Type; b=Ug116Uwa9bvc64PezFD26Cv01i9TgMp++rV64/H1bOU5tnQH8y6mryY0CBwQRCr23Hk2virWX1yXpaU2MvR2HAKU3KPZdSyYizrq+eOgAHjgwHAqmKY1kCm6ojGpOHv9UftURhJ0pVQho17h3+jsDbkgm3xVLnkFyDF5w0TMyYQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=raptorengineering.com; spf=pass smtp.mailfrom=raptorengineering.com; dkim=pass (1024-bit key) header.d=raptorengineering.com header.i=@raptorengineering.com header.b=ehLhXi/Y; arc=none smtp.client-ip=23.155.224.40 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=raptorengineering.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=raptorengineering.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=raptorengineering.com header.i=@raptorengineering.com header.b="ehLhXi/Y" Received: from localhost (localhost [127.0.0.1]) by mail.rptsys.com (Postfix) with ESMTP id DF82182856F8; Tue, 17 Jun 2025 09:31:21 -0500 (CDT) Received: from mail.rptsys.com ([127.0.0.1]) by localhost (vali.starlink.edu [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id 0--oJCWWxd3v; Tue, 17 Jun 2025 09:31:20 -0500 (CDT) Received: from localhost (localhost [127.0.0.1]) by mail.rptsys.com (Postfix) with ESMTP id 9211E8286FBD; Tue, 17 Jun 2025 09:31:20 -0500 (CDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.rptsys.com 9211E8286FBD DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=raptorengineering.com; s=B8E824E6-0BE2-11E6-931D-288C65937AAD; t=1750170680; bh=aunofFWjbhf0ebvsXaS+3/oQyj1Pul1Wqor5cviReNg=; h=Date:From:To:Message-ID:MIME-Version; b=ehLhXi/YHfQfXpXaWjPddQEuDeGS3q8spg8C8ai4iGm/jfzQn7dwU9toEg1UKEmXq MwDbyysltHWR7ZK8TrdthPgXXwx23APcc0C/c82PyJ/bTC7ToTtwQSmenMvfiVssjl 80WuuK6paHuD+hNb4Ppm8NS4z+aELtNZwldo6/Bg= X-Virus-Scanned: amavisd-new at rptsys.com Received: from mail.rptsys.com ([127.0.0.1]) by localhost (vali.starlink.edu [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id OsWGbPjsCkx3; Tue, 17 Jun 2025 09:31:20 -0500 (CDT) Received: from vali.starlink.edu (localhost [127.0.0.1]) by mail.rptsys.com (Postfix) with ESMTP id 5449982856F8; Tue, 17 Jun 2025 09:31:20 -0500 (CDT) Date: Tue, 17 Jun 2025 09:31:20 -0500 (CDT) From: Timothy Pearson To: Shawn Anastasio Cc: Bjorn Helgaas , Lorenzo Pieralisi , =?utf-8?q?Krzysztof_Wilczy?= =?utf-8?q?=C5=84ski?= , Manivannan Sadhasivam , Rob Herring , Krzysztof Kozlowski , Conor Dooley , chaitanya chundru , Bjorn Andersson , Konrad Dybcio , cros-qcom-dts-watchers@chromium.org, Jingoo Han , Bartosz Golaszewski , quic_vbadigan@quicnic.com, amitk@kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, jorge.ramirez@oss.qualcomm.com, Dmitry Baryshkov Message-ID: <1581123048.1308046.1750170680177.JavaMail.zimbra@raptorengineeringinc.com> Subject: [PATCH v7] PCI: Add pcie_link_is_active() to determine if the PCIe link Precedence: bulk X-Mailing-List: linux-arm-msm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Mailer: Zimbra 8.5.0_GA_3042 (ZimbraWebClient - GC137 (Linux)/8.5.0_GA_3042) Thread-Index: wD146B6OyvES+Feuh0TpgiI26pdz2Q== Thread-Topic: Add pcie_link_is_active() to determine if the PCIe link is active Introduce a common API to check if the PCIe link is active, replacing duplicate code in multiple locations. Signed-off-by: Krishna Chaitanya Chundru Signed-off-by: Shawn Anastasio Signed-off-by: Timothy Pearson --- arch/powerpc/kernel/eeh_driver.c | 8 +++++++- drivers/pci/hotplug/pciehp.h | 1 - drivers/pci/hotplug/pciehp_ctrl.c | 2 +- drivers/pci/hotplug/pciehp_hpc.c | 33 +++---------------------------- drivers/pci/pci.c | 31 ++++++++++++++++++++++++++--- include/linux/pci.h | 4 ++++ 6 files changed, 43 insertions(+), 36 deletions(-) diff --git a/arch/powerpc/kernel/eeh_driver.c b/arch/powerpc/kernel/eeh_driver.c index 441a3562bddd..4fdd62432f2c 100644 --- a/arch/powerpc/kernel/eeh_driver.c +++ b/arch/powerpc/kernel/eeh_driver.c @@ -1097,8 +1097,14 @@ void eeh_handle_normal_event(struct eeh_pe *pe) eeh_pe_dev_mode_mark(pe, EEH_DEV_REMOVED); pci_lock_rescan_remove(); - pci_hp_remove_devices(bus); + bus = eeh_pe_bus_get(pe); + if (bus) + pci_hp_remove_devices(bus); + else + pr_err("%s: PCI bus for PHB#%x-PE#%x disappeared\n", + __func__, pe->phb->global_number, pe->addr); pci_unlock_rescan_remove(); + /* The passed PE should no longer be used */ return; } diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h index debc79b0adfb..79df49cc9946 100644 --- a/drivers/pci/hotplug/pciehp.h +++ b/drivers/pci/hotplug/pciehp.h @@ -186,7 +186,6 @@ int pciehp_query_power_fault(struct controller *ctrl); int pciehp_card_present(struct controller *ctrl); int pciehp_card_present_or_link_active(struct controller *ctrl); int pciehp_check_link_status(struct controller *ctrl); -int pciehp_check_link_active(struct controller *ctrl); bool pciehp_device_replaced(struct controller *ctrl); void pciehp_release_ctrl(struct controller *ctrl); diff --git a/drivers/pci/hotplug/pciehp_ctrl.c b/drivers/pci/hotplug/pciehp_ctrl.c index bcc938d4420f..6cc1b27b3b11 100644 --- a/drivers/pci/hotplug/pciehp_ctrl.c +++ b/drivers/pci/hotplug/pciehp_ctrl.c @@ -260,7 +260,7 @@ void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events) /* Turn the slot on if it's occupied or link is up */ mutex_lock(&ctrl->state_lock); present = pciehp_card_present(ctrl); - link_active = pciehp_check_link_active(ctrl); + link_active = pcie_link_is_active(ctrl->pcie->port); if (present <= 0 && link_active <= 0) { if (ctrl->state == BLINKINGON_STATE) { ctrl->state = OFF_STATE; diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c index ebd342bda235..d29ce3715a44 100644 --- a/drivers/pci/hotplug/pciehp_hpc.c +++ b/drivers/pci/hotplug/pciehp_hpc.c @@ -221,33 +221,6 @@ static void pcie_write_cmd_nowait(struct controller *ctrl, u16 cmd, u16 mask) pcie_do_write_cmd(ctrl, cmd, mask, false); } -/** - * pciehp_check_link_active() - Is the link active - * @ctrl: PCIe hotplug controller - * - * Check whether the downstream link is currently active. Note it is - * possible that the card is removed immediately after this so the - * caller may need to take it into account. - * - * If the hotplug controller itself is not available anymore returns - * %-ENODEV. - */ -int pciehp_check_link_active(struct controller *ctrl) -{ - struct pci_dev *pdev = ctrl_dev(ctrl); - u16 lnk_status; - int ret; - - ret = pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status); - if (ret == PCIBIOS_DEVICE_NOT_FOUND || PCI_POSSIBLE_ERROR(lnk_status)) - return -ENODEV; - - ret = !!(lnk_status & PCI_EXP_LNKSTA_DLLLA); - ctrl_dbg(ctrl, "%s: lnk_status = %x\n", __func__, lnk_status); - - return ret; -} - static bool pci_bus_check_dev(struct pci_bus *bus, int devfn) { u32 l; @@ -467,7 +440,7 @@ int pciehp_card_present_or_link_active(struct controller *ctrl) if (ret) return ret; - return pciehp_check_link_active(ctrl); + return pcie_link_is_active(ctrl_dev(ctrl)); } int pciehp_query_power_fault(struct controller *ctrl) @@ -614,7 +587,7 @@ static void pciehp_ignore_link_change(struct controller *ctrl, * Synthesize it to ensure that it is acted on. */ down_read_nested(&ctrl->reset_lock, ctrl->depth); - if (!pciehp_check_link_active(ctrl) || pciehp_device_replaced(ctrl)) + if (!pcie_link_is_active(ctrl_dev(ctrl)) || pciehp_device_replaced(ctrl)) pciehp_request(ctrl, ignored_events); up_read(&ctrl->reset_lock); } @@ -921,7 +894,7 @@ int pciehp_slot_reset(struct pcie_device *dev) pcie_capability_write_word(dev->port, PCI_EXP_SLTSTA, PCI_EXP_SLTSTA_DLLSC); - if (!pciehp_check_link_active(ctrl)) + if (!pcie_link_is_active(ctrl_dev(ctrl))) pciehp_request(ctrl, PCI_EXP_SLTSTA_DLLSC); return 0; diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index e9448d55113b..ad639e60f3bd 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -4908,7 +4908,6 @@ int pci_bridge_wait_for_secondary_bus(struct pci_dev *dev, char *reset_type) return 0; if (pcie_get_speed_cap(dev) <= PCIE_SPEED_5_0GT) { - u16 status; pci_dbg(dev, "waiting %d ms for downstream link\n", delay); msleep(delay); @@ -4924,8 +4923,7 @@ int pci_bridge_wait_for_secondary_bus(struct pci_dev *dev, char *reset_type) if (!dev->link_active_reporting) return -ENOTTY; - pcie_capability_read_word(dev, PCI_EXP_LNKSTA, &status); - if (!(status & PCI_EXP_LNKSTA_DLLLA)) + if (pcie_link_is_active(dev) <= 0) return -ENOTTY; return pci_dev_wait(child, reset_type, @@ -6230,6 +6228,33 @@ void pcie_print_link_status(struct pci_dev *dev) } EXPORT_SYMBOL(pcie_print_link_status); +/** + * pcie_link_is_active() - Checks if the link is active or not + * @pdev: PCI device to query + * + * Check whether the physical link is active or not. Note it is + * possible that the card is removed immediately after this so the + * caller may need to take it into account. + * + * If the PCI device itself is not available anymore returns + * %-ENODEV. + * + * Return: link state, or -ENODEV if the config read failes. + */ +int pcie_link_is_active(struct pci_dev *pdev) +{ + u16 lnk_status; + int ret; + + ret = pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status); + if (ret == PCIBIOS_DEVICE_NOT_FOUND || PCI_POSSIBLE_ERROR(lnk_status)) + return -ENODEV; + + pci_dbg(pdev, "lnk_status = %x\n", lnk_status); + return !!(lnk_status & PCI_EXP_LNKSTA_DLLLA); +} +EXPORT_SYMBOL(pcie_link_is_active); + /** * pci_select_bars - Make BAR mask from the type of resource * @dev: the PCI device for which BAR mask is made diff --git a/include/linux/pci.h b/include/linux/pci.h index 05e68f35f392..5d1c9f718ac8 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1993,6 +1993,7 @@ pci_release_mem_regions(struct pci_dev *pdev) pci_select_bars(pdev, IORESOURCE_MEM)); } +int pcie_link_is_active(struct pci_dev *dev); #else /* CONFIG_PCI is not enabled */ static inline void pci_set_flags(int flags) { } @@ -2141,6 +2142,9 @@ pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs, { return -ENOSPC; } + +static inline bool pcie_link_is_active(struct pci_dev *dev) +{ return false; } #endif /* CONFIG_PCI */ /* Include architecture-dependent settings and functions */