diff options
| -rw-r--r-- | drivers/pci/quirks.c | 32 |
1 files changed, 30 insertions, 2 deletions
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index faf02dd0001..9b2f0d96900 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -2206,6 +2206,33 @@ static int __devinit host_bridge_with_leaf(struct pci_dev *host_bridge) return found; } +#define PCI_HT_CAP_SLAVE_CTRL0 4 /* link control */ +#define PCI_HT_CAP_SLAVE_CTRL1 8 /* link control to */ + +static int __devinit is_end_of_ht_chain(struct pci_dev *dev) +{ + int pos, ctrl_off; + int end = 0; + u16 flags, ctrl; + + pos = pci_find_ht_capability(dev, HT_CAPTYPE_SLAVE); + + if (!pos) + goto out; + + pci_read_config_word(dev, pos + PCI_CAP_FLAGS, &flags); + + ctrl_off = ((flags >> 10) & 1) ? + PCI_HT_CAP_SLAVE_CTRL0 : PCI_HT_CAP_SLAVE_CTRL1; + pci_read_config_word(dev, pos + ctrl_off, &ctrl); + + if (ctrl & (1 << 6)) + end = 1; + +out: + return end; +} + static void __devinit nv_ht_enable_msi_mapping(struct pci_dev *dev) { struct pci_dev *host_bridge; @@ -2230,8 +2257,9 @@ static void __devinit nv_ht_enable_msi_mapping(struct pci_dev *dev) if (!found) return; - /* don't enable host_bridge with leaf directly here */ - if (host_bridge == dev && host_bridge_with_leaf(host_bridge)) + /* don't enable end_device/host_bridge with leaf directly here */ + if (host_bridge == dev && is_end_of_ht_chain(host_bridge) && + host_bridge_with_leaf(host_bridge)) goto out; /* root did that ! */ |