diff options
| author | Yinghai Lu <yinghai@kernel.org> | 2013-11-05 13:34:38 -0700 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2013-11-05 16:36:02 -0700 |
| commit | cf3e1feba7f906f233790f1806592730a88f584d (patch) | |
| tree | f078aab6108d10ffe9f8859967fbb30b8aa8bf71 /drivers/pci | |
| parent | 6b87e700cd65120b70aaa097a8f4e7f22f1945ee (diff) | |
PCI: Workaround missing pci_set_master in pci drivers
Ben Herrenschmidt found that commit 928bea964827 ("PCI: Delay enabling
bridges until they're needed") breaks PCI in some powerpc environments.
The reason is that the PCIe port driver will call pci_enable_device() on
the bridge, so the device is enabled, but skips pci_set_master because
pcie_port_auto and no acpi on powerpc.
Because of that, pci_enable_bridge() later on (called as a result of the
child device driver doing pci_enable_device) will see the bridge as
already enabled and will not call pci_set_master() on it.
Fixed by add checking in pci_enable_bridge, and call pci_set_master
if driver skip that.
That will make the code more robot and wade off problem for missing
pci_set_master in drivers.
Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/pci')
| -rw-r--r-- | drivers/pci/pci.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 36cc8d5ae8b..7a92d81c28e 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1155,8 +1155,14 @@ static void pci_enable_bridge(struct pci_dev *dev) pci_enable_bridge(dev->bus->self); - if (pci_is_enabled(dev)) + if (pci_is_enabled(dev)) { + if (!dev->is_busmaster) { + dev_warn(&dev->dev, "driver skip pci_set_master, fix it!\n"); + pci_set_master(dev); + } return; + } + retval = pci_enable_device(dev); if (retval) dev_err(&dev->dev, "Error enabling bridge (%d), continuing\n", |