Commit bf4447fd authored by KarimAllah Ahmed's avatar KarimAllah Ahmed Committed by Bjorn Helgaas
Browse files

PCI/IOV: Skip BAR sizing for VFs 



Per PCIe r4.0, sec 9.3.4.1.11, the BAR registers in VF config space are all
RO Zero, so skip sizing them.

This is an optimization when enabling SR-IOV on a device with many VFs.

Suggested-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: default avatarKarimAllah Ahmed <karahmed@amazon.de>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent be20f6b0

drivers/pci/probe.c

+4 −0
Original line number Diff line number Diff line
@@ -329,6 +329,10 @@ static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom) 
	if (dev->non_compliant_bars)

		return;



	/* Per PCIe r4.0, sec 9.3.4.1.11, the VF BARs are all RO Zero */

	if (dev->is_virtfn)

		return;



	for (pos = 0; pos < howmany; pos++) {

		struct resource *res = &dev->resource[pos];

		reg = PCI_BASE_ADDRESS_0 + (pos << 2);