On Tue, 30 Jul 2019 10:37:18 +0100
"Dr. David Alan Gilbert (git)" <dgilb...@redhat.com> wrote:
> From: "Dr. David Alan Gilbert" <dgilb...@redhat.com>
>
> ACS was added in 4.0 unconditionally, this breaks migration
> compatibility.
> Allow ACS to be disabled by adding a property that's
> checked by pcie_root_port.
>
> Unfortunately pcie-root-port doesn't have any instance data,
> so there's no where for that flag to live, so stuff it into
> PCIESlot.
>
> Signed-off-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
> ---
> hw/pci-bridge/pcie_root_port.c | 3 ++-
> include/hw/pci/pcie_port.h | 2 ++
> 2 files changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/hw/pci-bridge/pcie_root_port.c b/hw/pci-bridge/pcie_root_port.c
> index 09019ca05d..1d8a778709 100644
> --- a/hw/pci-bridge/pcie_root_port.c
> +++ b/hw/pci-bridge/pcie_root_port.c
> @@ -111,7 +111,7 @@ static void rp_realize(PCIDevice *d, Error **errp)
> pcie_aer_root_init(d);
> rp_aer_vector_update(d);
>
> - if (rpc->acs_offset) {
> + if (rpc->acs_offset && !s->disable_acs) {
it's not like it would be used per instance,
so could we use class property and with rpc->disable_acs instead of PCIESlot?
> pcie_acs_init(d, rpc->acs_offset);
> }
> return;
> @@ -145,6 +145,7 @@ static void rp_exit(PCIDevice *d)
> static Property rp_props[] = {
> DEFINE_PROP_BIT(COMPAT_PROP_PCP, PCIDevice, cap_present,
> QEMU_PCIE_SLTCAP_PCP_BITNR, true),
> + DEFINE_PROP_BOOL("disable-acs", PCIESlot, disable_acs, false),
> DEFINE_PROP_END_OF_LIST()
> };
>
> diff --git a/include/hw/pci/pcie_port.h b/include/hw/pci/pcie_port.h
> index 09586f4641..7515430087 100644
> --- a/include/hw/pci/pcie_port.h
> +++ b/include/hw/pci/pcie_port.h
> @@ -53,6 +53,8 @@ struct PCIESlot {
> PCIExpLinkSpeed speed;
> PCIExpLinkWidth width;
>
> + /* Disable ACS (really for a pcie_root_port) */
> + bool disable_acs;
> QLIST_ENTRY(PCIESlot) next;
> };
>
