Hi Liviu, Issue may not be only with SR-IOV resources. I am not an expert with Linux PCI core. But i am trying to understand how even for a non SR-IOV capable device's resource, gets a parent associated with it. When a PCI device driver calls pci_enable_device() which inturn calls 'arch/arm64/kernel/pci.c' pcibios_enable_device() which uses Linux PCI core API 'pci_enable_resources'. This API checks 'res->parent' for all valid resources before enabling them, otherwise it fails. if (!r->parent) { dev_err(&dev->dev, "device not available " "(can't reserve %pR)\n", r); return -EINVAL; } Can you please let me know where this hierarchy is being set for 'pcibios_enable_resources' to work. I could only find request_resource() API which sets the parent and pci_claim_resource() uses this. Thanks, Sunil. On Fri, May 16, 2014 at 6:54 PM, Liviu Dudau <Liviu.Dudau@xxxxxxx> wrote: > Hi Sunil, > > On Fri, May 16, 2014 at 11:33:04AM +0100, Sunil Kovvuri wrote: >> Hi Liviu, >> >> I am using your ARM64 PCIe patches to write a PCIe host controller >> driver for our SOC. I am facing an issue with SR-IOV capable device. >> >> Consider an PCI Express endpoint connected to a PCI Express >> Root Port. The PCI Express endpoint provides PCI-SIG SR-IOV >> capabilities with a single physical function and a large number >> of virtual functions. The Root Port contains a pci-pci bridge in >> between it and the SR-IOV device. >> >> 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". >> >> 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'. >> >> Let me know if this is okay. >> >> diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c >> index 9f29c9a..fbfb48f 100644 >> --- a/arch/arm64/kernel/pci.c >> +++ b/arch/arm64/kernel/pci.c >> @@ -125,6 +125,21 @@ resource_size_t pcibios_align_resource(void >> *data, const struct resource *res, >> return res->start; >> } >> >> +int pcibios_add_device(struct pci_dev *pdev) >> +{ >> + unsigned int i, type_mask = IORESOURCE_IO | IORESOURCE_MEM; >> + struct resource *res; >> + >> + for (i = 0; i < PCI_NUM_RESOURCES; i++) { >> + res = &pdev->resource[i]; >> + if (res->parent || !(res->flags & type_mask)) >> + continue; >> + pci_claim_resource(pdev, i); >> + } >> + >> > > I would like not to have to add your patch in this file as I am trying to > remove it entirely. I don't have an SR-IOV capable device in my setup so > I am not able to debug your problem, but could you have a go and try to > figure out why the SR-IOV resources do not get a parent associated with > when they get created? > > Many thanks, > Liviu > > > -- > ==================== > | I would like to | > | fix the world, | > | but they're not | > | giving me the | > \ source code! / > --------------- > ¯\_(ツ)_/¯ > -- 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