diff options
| author | Yu Zhao <yu.zhao@intel.com> | 2009-06-13 15:52:15 +0800 |
|---|---|---|
| committer | Jesse Barnes <jbarnes@virtuousgeek.org> | 2009-06-16 14:30:16 -0700 |
| commit | c12ff1df5f114484e3d8abd028769a624cc3399f (patch) | |
| tree | 410cb0adf85a52772d5acf6621b421c33b44820a | |
| parent | f85876ba82281f15bc4da11e41b94243a8b2b5b4 (diff) | |
PCI: support Secondary Bus Reset
PCI-to-PCI Bridge 1.2 specifies that the Secondary Bus Reset bit can
force the assertion of RST# on the secondary interface, which can be
used to reset all devices including subordinates under this bus. This
can be used to reset a function if this function is the only device
under this bus.
Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
| -rw-r--r-- | drivers/pci/pci.c | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 2e58acc66a8..c56a4a0355a 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -2162,6 +2162,33 @@ static int pci_pm_reset(struct pci_dev *dev, int probe) return 0; } +static int pci_parent_bus_reset(struct pci_dev *dev, int probe) +{ + u16 ctrl; + struct pci_dev *pdev; + + if (dev->subordinate) + return -ENOTTY; + + list_for_each_entry(pdev, &dev->bus->devices, bus_list) + if (pdev != dev) + return -ENOTTY; + + if (probe) + return 0; + + pci_read_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, &ctrl); + ctrl |= PCI_BRIDGE_CTL_BUS_RESET; + pci_write_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, ctrl); + msleep(100); + + ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET; + pci_write_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, ctrl); + msleep(100); + + return 0; +} + static int pci_dev_reset(struct pci_dev *dev, int probe) { int rc; @@ -2183,6 +2210,10 @@ static int pci_dev_reset(struct pci_dev *dev, int probe) goto done; rc = pci_pm_reset(dev, probe); + if (rc != -ENOTTY) + goto done; + + rc = pci_parent_bus_reset(dev, probe); done: if (!probe) { up(&dev->dev.sem); |