On Mon, May 19, 2014 at 6:31 PM, Arnd Bergmann <arnd@xxxxxxxx> wrote: > On Friday 16 May 2014 16:03:04 Sunil Kovvuri wrote: >> When the SR-IOV capable device's driver tries to enable sriov >> (pci_enable_sriov()) it fails to create/add PCI device for each >> virtual function reporting "not enough MMIO resources for SR-IOV". > > I assume you have checked that there is indeed enough MMIO space > available, right? > Yes, i have checked for enough MMIO space multiple times. >> In sriov_enable() (drivers/pci/iov.c) >> >> 296 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { >> 297 bars |= (1 << (i + PCI_IOV_RESOURCES)); >> 298 res = dev->resource + PCI_IOV_RESOURCES + i; >> 299 if (res->parent) >> 300 nres++; >> 301 } >> 302 if (nres != iov->nres) { >> 303 dev_err(&dev->dev, "not enough MMIO resources for >> SR-IOV\n"); >> 304 return -ENOMEM; >> 305 } >> >> Here its checking if physical function's IOV resource has a parent or not. >> Which is pci-pci bridge in this case. Otherwise it doesn't consider >> that resource. >> >> Added below api to your patch. >> This will try to claim a resource while creating a PCI device which >> inturn sets 'res->parent'. > > This looks like the wrong approach. The PCI host controller should > really have been registered with the root 'iomem_resource' during > the probe of the host controller. > > Arnd I didn't get this, if a SR-IOV device is connected to a PCI-PCI bridge and inturn bridge connected to root port. Then the parent bus is not root, but the bridge. The issue is either hierarchy should not be checked for SR-IOV resources or someone should set the hierarchy (i.e parent resources). Regards, Sunil. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html