On Wed, May 21, 2014 at 04:45:29PM +0530, Sunil Kovvuri wrote: > Hi Liviu, > > Sorry for the trouble. > I got why 'res->parent' is not set in my case. > Basically my SR-IOV device has fixed resources, so resources will not > be allocated/assigned and hence parent resource is not set. > I will move the resource claiming to host controller driver as a fixup > so that parent resource hierarchy is set. > > Thanks for the support. Glad you worked out the cause for the problem. I will still at to my list of ToDo things to investigate resource parenting with my patchset. Best regards, Liviu > > Regards, > Sunil. > > > On Fri, May 16, 2014 at 11:12 PM, Sunil Kovvuri <sunil.kovvuri@xxxxxxxxx> wrote: > > 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 linux-pci" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- ------------------- .oooO ( ) \ ( Oooo. \_) ( ) ) / (_/ One small step for me ... -- 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