From patchwork Wed Jul 3 14:04:51 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mika Westerberg X-Patchwork-Id: 256644 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3BF832C0092 for ; Thu, 4 Jul 2013 00:03:08 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932816Ab3GCOCg (ORCPT ); Wed, 3 Jul 2013 10:02:36 -0400 Received: from mga03.intel.com ([143.182.124.21]:16372 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932661Ab3GCOCd (ORCPT ); Wed, 3 Jul 2013 10:02:33 -0400 Received: from azsmga002.ch.intel.com ([10.2.17.35]) by azsmga101.ch.intel.com with ESMTP; 03 Jul 2013 07:02:32 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.87,988,1363158000"; d="scan'208";a="263621141" Received: from blue.fi.intel.com ([10.237.72.156]) by AZSMGA002.ch.intel.com with ESMTP; 03 Jul 2013 07:01:58 -0700 Received: by blue.fi.intel.com (Postfix, from userid 1004) id A64AFE0095; Wed, 3 Jul 2013 17:04:55 +0300 (EEST) From: Mika Westerberg To: Greg Kroah-Hartman , Bjorn Helgaas , "Rafael J. Wysocki" Cc: Jesse Barnes , Yinghai Lu , john.ronciak@intel.com, miles.j.penner@intel.com, bruce.w.allan@intel.com, Heikki Krogerus , "Kirill A. Shutemov" , Mika Westerberg , linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org Subject: [PATCH v2 4/8] PCI: acpiphp: check for new devices on enabled host Date: Wed, 3 Jul 2013 17:04:51 +0300 Message-Id: <1372860295-8306-5-git-send-email-mika.westerberg@linux.intel.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1372860295-8306-1-git-send-email-mika.westerberg@linux.intel.com> References: <1372860295-8306-1-git-send-email-mika.westerberg@linux.intel.com> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org From: "Kirill A. Shutemov" Current acpiphp_check_bridge() implementation is pretty dumb: - it enables the slot if it's not enabled and the slot status is ACPI_STA_ALL; - it disables the slot if it's enabled and slot is not in ACPI_STA_ALL state. This behavior is not enough to handle Thunderbolt chaining case properly. We need to actually rescan for new devices even if a device has already in the slot. The new implementation disables and stops the slot if it's not in ACPI_STA_ALL state. For ACPI_STA_ALL state we first trim devices which don't respond. In order to support that we introduce a new function pci_trim_stale_devices() that goes through the child devices of a given bus, check if the device is gone and in that case stop and remove the device. Once we have trimmed the bus we start looking for any new devices that might have appeared on the bus. We do that even if the slot is already enabled (SLOT_ENABLED). Signed-off-by: Kirill A. Shutemov Signed-off-by: Mika Westerberg --- drivers/pci/hotplug/acpiphp_glue.c | 55 ++++++++++++++++++-------------------- drivers/pci/remove.c | 20 ++++++++++++++ include/linux/pci.h | 1 + 3 files changed, 47 insertions(+), 29 deletions(-) diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c index 0f4da3b..c9ec06e 100644 --- a/drivers/pci/hotplug/acpiphp_glue.c +++ b/drivers/pci/hotplug/acpiphp_glue.c @@ -865,43 +865,40 @@ int acpiphp_eject_slot(struct acpiphp_slot *slot) * Iterate over all slots under this bridge and make sure that if a * card is present they are enabled, and if not they are disabled. */ -static int acpiphp_check_bridge(struct acpiphp_bridge *bridge) +static void acpiphp_check_bridge(struct acpiphp_bridge *bridge) { struct acpiphp_slot *slot; - int retval = 0; - int enabled, disabled; - - enabled = disabled = 0; list_for_each_entry(slot, &bridge->slots, node) { - unsigned int status = get_slot_status(slot); - if (slot->flags & SLOT_ENABLED) { - if (status == ACPI_STA_ALL) - continue; - retval = acpiphp_disable_slot(slot); - if (retval) { - err("Error occurred in disabling\n"); - goto err_exit; - } else { - acpiphp_eject_slot(slot); + struct pci_bus *bus = slot->bridge->pci_bus; + struct pci_dev *dev, *tmp; + int retval; + + mutex_lock(&slot->crit_sect); + /* wake up all functions */ + retval = power_on_slot(slot); + if (retval) + goto unlock; + + if (get_slot_status(slot) == ACPI_STA_ALL) { + /* remove stale devices if any */ + list_for_each_entry_safe(dev, tmp, &bus->devices, + bus_list) { + if (PCI_SLOT(dev->devfn) == slot->device) + pci_trim_stale_devices(dev); } - disabled++; + + /* configure all functions */ + retval = enable_device(slot); + if (retval) + power_off_slot(slot); } else { - if (status != ACPI_STA_ALL) - continue; - retval = acpiphp_enable_slot(slot); - if (retval) { - err("Error occurred in enabling\n"); - goto err_exit; - } - enabled++; + disable_device(slot); + power_off_slot(slot); } +unlock: + mutex_unlock(&slot->crit_sect); } - - dbg("%s: %d enabled, %d disabled\n", __func__, enabled, disabled); - - err_exit: - return retval; } static void acpiphp_set_hpp_values(struct pci_bus *bus) diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c index 8fc54b7..77b7a64 100644 --- a/drivers/pci/remove.c +++ b/drivers/pci/remove.c @@ -112,6 +112,26 @@ void pci_stop_and_remove_bus_device(struct pci_dev *dev) } EXPORT_SYMBOL(pci_stop_and_remove_bus_device); +/** + * pci_trim_stale_devices - remove stale device or any stale child + */ +void pci_trim_stale_devices(struct pci_dev *dev) +{ + struct pci_bus *bus = dev->subordinate; + struct pci_dev *child, *tmp; + bool alive; + u32 l; + + /* check if the device responds */ + alive = pci_bus_read_dev_vendor_id(dev->bus, dev->devfn, &l, 0); + if (!alive) + pci_stop_and_remove_bus_device(dev); + + if (alive && bus) + list_for_each_entry_safe(child, tmp, &bus->devices, bus_list) + pci_trim_stale_devices(child); +} + void pci_stop_root_bus(struct pci_bus *bus) { struct pci_dev *child, *tmp; diff --git a/include/linux/pci.h b/include/linux/pci.h index 3a24e4f..8f6e7a0 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -754,6 +754,7 @@ struct pci_dev *pci_dev_get(struct pci_dev *dev); void pci_dev_put(struct pci_dev *dev); void pci_remove_bus(struct pci_bus *b); void pci_stop_and_remove_bus_device(struct pci_dev *dev); +void pci_trim_stale_devices(struct pci_dev *dev); void pci_stop_root_bus(struct pci_bus *bus); void pci_remove_root_bus(struct pci_bus *bus); void pci_setup_cardbus(struct pci_bus *bus);