From 296ccb086dfb89b5b8d73ef08c795ffdff12a597 Mon Sep 17 00:00:00 2001 From: Yuji Shimada Date: Fri, 3 Apr 2009 16:41:46 +0900 Subject: [PATCH] PCI: Setup disabled bridges even if buses are added This patch sets up disabled bridges even if buses have already been added. pci_assign_unassigned_resources is called after buses are added. pci_assign_unassigned_resources calls pci_bus_assign_resources. pci_bus_assign_resources calls pci_setup_bridge to configure BARs of bridges. Currently pci_setup_bridge returns immediately if the bus have already been added. So pci_assign_unassigned_resources can't configure BARs of bridges that were added in a disabled state; this patch fixes the issue. On logical hot-add, we need to prevent the kernel from re-initializing bridges that have already been initialized. To achieve this, pci_setup_bridge returns immediately if the bridge have already been enabled. We don't need to check whether the specified bus is a root bus or not. pci_setup_bridge is not called on a root bus, because a root bus does not have a bridge. The patch adds a new helper function, pci_is_enabled. I made the function name similar to pci_is_managed. The codes which use enable_cnt directly are changed to use pci_is_enabled. Acked-by: Alex Chiang Signed-off-by: Yuji Shimada Signed-off-by: Jesse Barnes --- drivers/pci/bus.c | 2 +- drivers/pci/pci-sysfs.c | 2 +- drivers/pci/pci.c | 4 ++-- drivers/pci/setup-bus.c | 2 +- include/linux/pci.h | 5 +++++ 5 files changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c index 68f91a25259..97a8194063b 100644 --- a/drivers/pci/bus.c +++ b/drivers/pci/bus.c @@ -184,7 +184,7 @@ void pci_enable_bridges(struct pci_bus *bus) list_for_each_entry(dev, &bus->devices, bus_list) { if (dev->subordinate) { - if (atomic_read(&dev->enable_cnt) == 0) { + if (!pci_is_enabled(dev)) { retval = pci_enable_device(dev); pci_set_master(dev); } diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index e9a8706a640..cd8e682c04a 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -148,7 +148,7 @@ static ssize_t is_enabled_store(struct device *dev, return -EPERM; if (!val) { - if (atomic_read(&pdev->enable_cnt) != 0) + if (pci_is_enabled(pdev)) pci_disable_device(pdev); else result = -EIO; diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 445fb6f7ea3..16fd0d4c316 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -844,7 +844,7 @@ static int do_pci_enable_device(struct pci_dev *dev, int bars) */ int pci_reenable_device(struct pci_dev *dev) { - if (atomic_read(&dev->enable_cnt)) + if (pci_is_enabled(dev)) return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1); return 0; } @@ -1042,7 +1042,7 @@ static void do_pci_disable_device(struct pci_dev *dev) */ void pci_disable_enabled_device(struct pci_dev *dev) { - if (atomic_read(&dev->enable_cnt)) + if (pci_is_enabled(dev)) do_pci_disable_device(dev); } diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index 334285a8e23..8d9da9d30a6 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -144,7 +144,7 @@ static void pci_setup_bridge(struct pci_bus *bus) struct pci_bus_region region; u32 l, bu, lu, io_upper16; - if (!pci_is_root_bus(bus) && bus->is_added) + if (pci_is_enabled(bridge)) return; dev_info(&bridge->dev, "PCI bridge, secondary bus %04x:%02x\n", diff --git a/include/linux/pci.h b/include/linux/pci.h index a7fe4bbd7ff..72698d89e76 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -674,6 +674,11 @@ int __must_check pci_reenable_device(struct pci_dev *); int __must_check pcim_enable_device(struct pci_dev *pdev); void pcim_pin_device(struct pci_dev *pdev); +static inline int pci_is_enabled(struct pci_dev *pdev) +{ + return (atomic_read(&pdev->enable_cnt) > 0); +} + static inline int pci_is_managed(struct pci_dev *pdev) { return pdev->is_managed; -- 2.41.1