On Tue, 2014-08-19 at 21:08 +0800, arei.gong...@huawei.com wrote:
> From: Gonglei <arei.gong...@huawei.com>
Hi,
>
> Right now, ARI Forwarding dose not support in QEMU.
I would replace the above sentence with "ARI Forwarding is not supported".
By the way, there is some support for ARI, I don't know if
is enabled yet. I'll have a look.
> According to PCIe spec section 7.3.1, only slot 0 with
> the device attached to logic bus representing the link from
> downstream ports and root ports.
>
> So, adding check about slot 0 for PCIe downstream ports and
> root ports, which avoid useless operation, both hotplug and
> coldplug.
>
> Signed-off-by: Gonglei <arei.gong...@huawei.com>
> ---
> hw/pci/pci.c | 41 +++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 41 insertions(+)
>
> diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> index 351d320..f2d267f 100644
> --- a/hw/pci/pci.c
> +++ b/hw/pci/pci.c
> @@ -773,6 +773,42 @@ static int pci_init_multifunction(PCIBus *bus, PCIDevice
> *dev)
> return 0;
> }
>
> +static int pci_check_pcie_port(PCIBus *bus, PCIDevice *dev)
> +{
> + Object *obj = OBJECT(bus);
> +
> + if (!strcmp(object_get_typename(obj), TYPE_PCIE_BUS)) {
Maybe there is another way to check that this is a PCIe bus?
> + DeviceState *parent = qbus_get_parent(BUS(obj));
> + const char *name = object_get_typename(OBJECT(parent));
> +
> + /*
> + * Root ports and downstream ports of switches are the hot
> + * pluggable ports in a PCI Express hierarchy.
> + * PCI Express supports chip-to-chip interconnect, a PCIe link can
> + * only connect one pci device/Switch/EndPoint or PCI-bridge.
> + *
> + * 7.3. Configuration Transaction Rules (PCI Express specification
> 3.0)
> + * 7.3.1. Device Number
> + *
> + * Downstream Ports that do not have ARI Forwarding enabled must
> + * associate only Device 0 with the device attached to the Logical
> Bus
> + * representing the Link from the Port.
> + *
> + * Right now, ARI Forwarding dose not support. So, only slot 0 is
As above, maybe replace it with "ARI Forwarding is not supported"
> + * supported, regardless of hotplug or coldplug.
> + */
> + if (!strcmp(name, "ioh3420") || !strcmp(name, "xio3130-downstream"))
> {
Please use port_type flag from extended configuration space, don't use device
names.
If you need help for this, let me know.
> + if (PCI_SLOT(dev->devfn) != 0) {
> + error_report("Unsupported PCI slot %d for %s ports, only "
> + "supported slot 0", PCI_SLOT(dev->devfn), name);
> + return -1;
> + }
> + }
> + }
> +
> + return 0;
> +}
> +
> static void pci_config_alloc(PCIDevice *pci_dev)
> {
> int config_size = pci_config_size(pci_dev);
> @@ -871,6 +907,11 @@ static PCIDevice *do_pci_register_device(PCIDevice
> *pci_dev, PCIBus *bus,
> return NULL;
> }
>
> + if (pci_check_pcie_port(bus, pci_dev)) {
> + do_pci_unregister_device(pci_dev);
> + return NULL;
> + }
It is possible to move the above check earlier in do_pci_register_device
function?
Maybe move it into the first if statement(s)?
Thanks,
Marcel
> +
> if (!config_read)
> config_read = pci_default_read_config;
> if (!config_write)
