tree ebffdc085479c05d67d6e745216316590a120a80
parent e69b7663b06e8af9cc2dae16e6ec906a64c3c63d
author Alexandru Elisei <alexandru.elisei@arm.com> 1626195991 +0100
committer Will Deacon <will@kernel.org> 1626447754 +0100

arm/arm64: vfio: Add PCI Express Capability Structure

It turns out that some Linux drivers (like Realtek R8169) fall back to a
device-specific configuration method if the device is not PCI Express
capable:

[    1.433825] r8169 0000:00:00.0 enp0s0: No native access to PCI extended config space, falling back to CSI

Add the PCI Express Capability Structure and populate it for assigned
devices, as this is how the Linux PCI driver determines if a device is PCI
Express capable.

Because we don't emulate a PCI Express link, a root complex or any slot
related properties, the PCI Express capability is kept as small as possible
by ignoring those fields.

Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Link: https://lore.kernel.org/r/20210713170631.155595-5-alexandru.elisei@arm.com
Signed-off-by: Will Deacon <will@kernel.org>