diff options
| author | Yinghai Lu <yinghai@kernel.org> | 2013-09-28 13:13:07 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-09-28 13:25:30 -0700 |
| commit | f41f064cf4352e6a7fd982f1de8a690897702513 (patch) | |
| tree | 4fcdb114235d5453e0c4abaa06a703f424f991d2 | |
| parent | aeebc264575f486c4cadc3f9d02f0049ae790c97 (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>
| -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 e8ccf6c0f08..bdd64b1b481 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", |