Commit d2f07120 authored by Pierre Morel's avatar Pierre Morel Committed by Cornelia Huck
Browse files

s390x/pci: handle PCIBridge bus number 



The PCI bus number is usually set by the host during the enumeration.

In the s390 architecture we neither get a Device Tree nor have an
enumeration understanding bridge devices.

Let's fake the enumeration on reset and set the PCI_PRIMARY_BUS,
PCI_SECONDARY_BUS and PCI_SUBORDINATE_BUS config entries for the
bridges.

Let's add the configuration of these three config entries on bridge hot
plug.

The bus number is calculated based on a new entry, bus_num of the
S390pciState device.

This commit is inspired by what spapr pci does.

Signed-off-by: default avatarPierre Morel <pmorel@linux.vnet.ibm.com>
Signed-off-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
parent df8dd91b

hw/s390x/s390-pci-bus.c

+52 −0
Original line number Diff line number Diff line
@@ -576,6 +576,7 @@ static int s390_pcihost_init(SysBusDevice *dev) 
    s->iommu_table = g_hash_table_new_full(g_int64_hash, g_int64_equal,

                                           NULL, g_free);

    s->zpci_table = g_hash_table_new_full(g_int_hash, g_int_equal, NULL, NULL);

    s->bus_no = 0;

    QTAILQ_INIT(&s->pending_sei);

    QTAILQ_INIT(&s->zpci_devs);

    return 0;
@@ -673,12 +674,24 @@ static void s390_pcihost_hot_plug(HotplugHandler *hotplug_dev, 
    if (object_dynamic_cast(OBJECT(dev), TYPE_PCI_BRIDGE)) {

        BusState *bus;

        PCIBridge *pb = PCI_BRIDGE(dev);

        PCIDevice *pdev = PCI_DEVICE(dev);



        pci_bridge_map_irq(pb, dev->id, s390_pci_map_irq);

        pci_setup_iommu(&pb->sec_bus, s390_pci_dma_iommu, s);



        bus = BUS(&pb->sec_bus);

        qbus_set_hotplug_handler(bus, DEVICE(s), errp);



        if (dev->hotplugged) {

            pci_default_write_config(pdev, PCI_PRIMARY_BUS, s->bus_no, 1);

            s->bus_no += 1;

            pci_default_write_config(pdev, PCI_SECONDARY_BUS, s->bus_no, 1);

            do {

                pdev = pdev->bus->parent_dev;

                pci_default_write_config(pdev, PCI_SUBORDINATE_BUS,

                                         s->bus_no, 1);

            } while (pdev->bus && pci_bus_num(pdev->bus));

        }

    } else if (object_dynamic_cast(OBJECT(dev), TYPE_PCI_DEVICE)) {

        pdev = PCI_DEVICE(dev);
@@ -812,6 +825,44 @@ out: 
    object_unparent(OBJECT(pbdev));

}



static void s390_pci_enumerate_bridge(PCIBus *bus, PCIDevice *pdev,

                                      void *opaque)

{

    S390pciState *s = opaque;

    unsigned int primary = s->bus_no;

    unsigned int subordinate = 0xff;

    PCIBus *sec_bus = NULL;



    if ((pci_default_read_config(pdev, PCI_HEADER_TYPE, 1) !=

         PCI_HEADER_TYPE_BRIDGE)) {

        return;

    }



    (s->bus_no)++;

    pci_default_write_config(pdev, PCI_PRIMARY_BUS, primary, 1);

    pci_default_write_config(pdev, PCI_SECONDARY_BUS, s->bus_no, 1);

    pci_default_write_config(pdev, PCI_SUBORDINATE_BUS, s->bus_no, 1);



    sec_bus = pci_bridge_get_sec_bus(PCI_BRIDGE(pdev));

    if (!sec_bus) {

        return;

    }



    pci_default_write_config(pdev, PCI_SUBORDINATE_BUS, subordinate, 1);

    pci_for_each_device(sec_bus, pci_bus_num(sec_bus),

                        s390_pci_enumerate_bridge, s);

    pci_default_write_config(pdev, PCI_SUBORDINATE_BUS, s->bus_no, 1);

}



static void s390_pcihost_reset(DeviceState *dev)

{

    S390pciState *s = S390_PCI_HOST_BRIDGE(dev);

    PCIBus *bus = s->parent_obj.bus;



    s->bus_no = 0;

    pci_for_each_device(bus, pci_bus_num(bus), s390_pci_enumerate_bridge, s);

}



static void s390_pcihost_class_init(ObjectClass *klass, void *data)

{

    SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
@@ -819,6 +870,7 @@ static void s390_pcihost_class_init(ObjectClass *klass, void *data) 
    HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);



    dc->cannot_instantiate_with_device_add_yet = true;

    dc->reset = s390_pcihost_reset;

    k->init = s390_pcihost_init;

    hc->plug = s390_pcihost_hot_plug;

    hc->unplug = s390_pcihost_hot_unplug;

hw/s390x/s390-pci-bus.h

+1 −0
Original line number Diff line number Diff line
@@ -310,6 +310,7 @@ typedef struct S390PCIBus { 
typedef struct S390pciState {

    PCIHostState parent_obj;

    uint32_t next_idx;

    int bus_no;

    S390PCIBus *bus;

    GHashTable *iommu_table;

    GHashTable *zpci_table;