Store more data about PCI VFs into the SRIOV to avoid reading them from the config space of all the PCI VFs. This is specially a useful optimization when bringing up thousands of VFs.
Cc: Bjorn Helgaas <[email protected]> Cc: [email protected] Cc: [email protected] Signed-off-by: KarimAllah Ahmed <[email protected]> --- v2 -> v3: * Update changelog * Move the call to pci_read_vf_config_common a bit later and use standard pci_read_config*. * Update whitespace. * Move the using barsz into its own patch. * Added a comment about the usage of subsystem vendor id, subsystem id, and class revision. * Make sure virtfn->is_virtfn is set before calling into pci_setup_device. v1 -> v2: * Rebase on latest + remove dependency on a non-upstream patch. drivers/pci/iov.c | 48 +++++++++++++++++++++++++++++++++++++++++------- drivers/pci/pci.h | 5 +++++ drivers/pci/probe.c | 18 ++++++++++++++---- 3 files changed, 60 insertions(+), 11 deletions(-) diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c index 677924a..10291a0 100644 --- a/drivers/pci/iov.c +++ b/drivers/pci/iov.c @@ -114,6 +114,36 @@ resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno) return dev->sriov->barsz[resno - PCI_IOV_RESOURCES]; } +static void pci_read_vf_config_common(struct pci_dev *virtfn) +{ + struct pci_dev *physfn = virtfn->physfn; + + BUG_ON(!virtfn->is_virtfn || physfn->is_virtfn); + + /* + * Per PCIe r4.0, sec 9.3.4.1.5, the value reported in the VF maybe + * different than the value reported in the PF. We assume here that all + * VFs would report the same revision ID. + */ + pci_read_config_dword(virtfn, PCI_CLASS_REVISION, + &physfn->sriov->class); + /* + * Per PCIe r4.0, sec 9.3.4.1.13, the field in the PF and the + * associated VFs must return the same value. + */ + pci_read_config_word(virtfn, PCI_SUBSYSTEM_VENDOR_ID, + &physfn->sriov->subsystem_vendor); + /* + * Per PCIe r4.0, sec 9.3.4.1.14, the value reported in the VF maybe + * different than the value reported in the PF. We assume here that all + * VFs would report the same subsystem ID. + */ + pci_read_config_word(virtfn, PCI_SUBSYSTEM_ID, + &physfn->sriov->subsystem_device); + pci_read_config_byte(virtfn, PCI_HEADER_TYPE, + &physfn->sriov->hdr_type); +} + int pci_iov_add_virtfn(struct pci_dev *dev, int id) { int i; @@ -134,15 +164,18 @@ int pci_iov_add_virtfn(struct pci_dev *dev, int id) goto failed0; virtfn->devfn = pci_iov_virtfn_devfn(dev, id); + virtfn->is_virtfn = 1; + virtfn->physfn = pci_dev_get(dev); + if (id == 0) + /* virtfn->{devfn,bus,is_virtfn,physfn} have to be initialized */ + pci_read_vf_config_common(virtfn); virtfn->vendor = dev->vendor; virtfn->device = iov->vf_device; rc = pci_setup_device(virtfn); if (rc) - goto failed0; + goto failed1; virtfn->dev.parent = dev->dev.parent; - virtfn->physfn = pci_dev_get(dev); - virtfn->is_virtfn = 1; virtfn->multifunction = 0; for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { @@ -163,10 +196,10 @@ int pci_iov_add_virtfn(struct pci_dev *dev, int id) sprintf(buf, "virtfn%u", id); rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf); if (rc) - goto failed1; + goto failed2; rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn"); if (rc) - goto failed2; + goto failed3; kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE); @@ -174,11 +207,12 @@ int pci_iov_add_virtfn(struct pci_dev *dev, int id) return 0; -failed2: +failed3: sysfs_remove_link(&dev->dev.kobj, buf); +failed2: + pci_stop_and_remove_bus_device(virtfn); failed1: pci_dev_put(dev); - pci_stop_and_remove_bus_device(virtfn); failed0: virtfn_remove_bus(dev->bus, bus); failed: diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index fcd8191..17e6688 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -271,6 +271,11 @@ struct pci_sriov { u16 driver_max_VFs; /* Max num VFs driver supports */ struct pci_dev *dev; /* Lowest numbered PF */ struct pci_dev *self; /* This PF */ + u8 hdr_type; /* VF header type */ + u32 class; /* VF device */ + u16 device; /* VF device */ + u16 subsystem_vendor; /* VF subsystem vendor */ + u16 subsystem_device; /* VF subsystem device */ resource_size_t barsz[PCI_SRIOV_NUM_BARS]; /* VF BAR size */ bool drivers_autoprobe; /* Auto probing of VFs by driver */ }; diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index ef53774..a96837e 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1454,7 +1454,9 @@ int pci_setup_device(struct pci_dev *dev) struct pci_bus_region region; struct resource *res; - if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type)) + if (dev->is_virtfn) + hdr_type = dev->physfn->sriov->hdr_type; + else if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type)) return -EIO; dev->sysdata = dev->bus->sysdata; @@ -1477,7 +1479,10 @@ int pci_setup_device(struct pci_dev *dev) dev->bus->number, PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn)); - pci_read_config_dword(dev, PCI_CLASS_REVISION, &class); + if (dev->is_virtfn) + class = dev->physfn->sriov->class; + else + pci_read_config_dword(dev, PCI_CLASS_REVISION, &class); dev->revision = class & 0xff; dev->class = class >> 8; /* upper 3 bytes */ @@ -1517,8 +1522,13 @@ int pci_setup_device(struct pci_dev *dev) goto bad; pci_read_irq(dev); pci_read_bases(dev, 6, PCI_ROM_ADDRESS); - pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor); - pci_read_config_word(dev, PCI_SUBSYSTEM_ID, &dev->subsystem_device); + if (dev->is_virtfn) { + dev->subsystem_vendor = dev->physfn->sriov->subsystem_vendor; + dev->subsystem_device = dev->physfn->sriov->subsystem_device; + } else { + pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor); + pci_read_config_word(dev, PCI_SUBSYSTEM_ID, &dev->subsystem_device); + } /* * Do the ugly legacy mode stuff here rather than broken chip -- 2.7.4
