| Message ID | 20210512184050.2915-1-stuart.w.hayes@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
| Series | PCI/portdrv: Use link bandwidth notification capability bit | expand |
On Thu, May 13, 2021 at 12:10:50AM +0530, Stuart Hayes wrote: > The pcieport driver can fail to attach to a downstream port that doesn't > support bandwidth notificaion. This can happen when, in ^^^^^^^^^^^ notification > pcie_port_device_register(), pci_init_service_irqs() tries (and fails) to > set up a bandwidth notificaion IRQ for a device that doesn't support it. ^^^^^^^^^^^ notification > --- a/drivers/pci/pcie/portdrv_core.c > +++ b/drivers/pci/pcie/portdrv_core.c > @@ -257,8 +257,13 @@ static int get_port_device_capability(struct pci_dev *dev) > services |= PCIE_PORT_SERVICE_DPC; > > if (pci_pcie_type(dev) == PCI_EXP_TYPE_DOWNSTREAM || > - pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) > - services |= PCIE_PORT_SERVICE_BWNOTIF; > + pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) { > + u32 linkcap; > + > + pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &linkcap); > + if (linkcap & PCI_EXP_LNKCAP_LBNC) > + services |= PCIE_PORT_SERVICE_BWNOTIF; > + } This *could* be #ifdef'ed to CONFIG_PCIE_BW (like CONFIG_PCIEAER a bit further above in this function). Apart from those nits, Reviewed-by: Lukas Wunner <lukas@wunner.de>
diff --git a/drivers/pci/pcie/portdrv_core.c b/drivers/pci/pcie/portdrv_core.c index e1fed6649c41..3ee63968deaa 100644 --- a/drivers/pci/pcie/portdrv_core.c +++ b/drivers/pci/pcie/portdrv_core.c @@ -257,8 +257,13 @@ static int get_port_device_capability(struct pci_dev *dev) services |= PCIE_PORT_SERVICE_DPC; if (pci_pcie_type(dev) == PCI_EXP_TYPE_DOWNSTREAM || - pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) - services |= PCIE_PORT_SERVICE_BWNOTIF; + pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) { + u32 linkcap; + + pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &linkcap); + if (linkcap & PCI_EXP_LNKCAP_LBNC) + services |= PCIE_PORT_SERVICE_BWNOTIF; + } return services; }
The pcieport driver can fail to attach to a downstream port that doesn't support bandwidth notificaion. This can happen when, in pcie_port_device_register(), pci_init_service_irqs() tries (and fails) to set up a bandwidth notificaion IRQ for a device that doesn't support it. This patch changes get_port_device_capability() to look at the link bandwidth notification capability bit in the link capabilities register of the port, instead of assuming that all downstream ports have that capability. Signed-off-by: Stuart Hayes <stuart.w.hayes@gmail.com> --- drivers/pci/pcie/portdrv_core.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)