The PCI core doesn't configure the PCIe MPS settings by itself. Each host
bridge driver has to call pcie_bus_configure_settings() to make this
happen.
Jon fixed this for pcie-iproc.c. I propose these similar patches for other
drivers.
HV guys, I included you because create_root_hv_pci_bus() is one place that
calls pci_scan_child_bus() but does not call pcie_bus_configure_settings().
I know you probably don't strictly *need* to configure MPS settings in a
paravirtual front-end, but the PCI core does other device configuration in
this path:
pci_scan_child_bus
pci_scan_slot
pci_scan_single_device
pci_device_add
pci_configure_device
pci_init_capabilities
and I would like to eventually migrate the MPS configuration into that same
path. Since we do this other configuration for HV devices already, I think
pcie_bus_configure_settings() should also work (even if it ends up not
doing anything to real devices).
It would make that eventual migration easier if all the
pci_scan_child_bus() callers had the same pattern of calling
pcie_bus_configure_settings().
So would it make sense to make a similar patch for HV? It looks easy to
add it to create_root_hv_pci_bus(), but I don't know exactly what to do
about pci_devices_present_work().
---
Bjorn Helgaas (3):
PCI: xilinx: Configure PCIe MPS settings
PCI: versatile: Configure PCIe MPS settings
PCI: xgene: Configure PCIe MPS settings
drivers/pci/host/pci-versatile.c | 4 +++-
drivers/pci/host/pci-xgene.c | 4 +++-
drivers/pci/host/pcie-xilinx.c | 4 +++-
3 files changed, 9 insertions(+), 3 deletions(-)
