Re: [SeaBIOS] [Qemu-devel] [PATCH RFC V2 12/17] hw/pci: introduce PCI Expander Bridge (PXB)

[Marcel Apfelbaum]

On 02/16/2015 02:58 PM, Alexander Graf wrote:
> On 16.02.15 10:54, Marcel Apfelbaum wrote:
> > From: Marcel Apfelbaum
> >
> > PXB is a "light-weight" host bridge whose purpose is to enable
> > the main host bridge to support multiple PCI root buses.
> >
> > As oposed to PCI-2-PCI bridge's secondary bus, PXB's bus
> > is a primary bus and can be associated with a NUMA node
> > (different from the main host bridge) allowing the guest OS
> > to recognize the proximity of a pass-through device to
> > other resources as RAM and CPUs.
> >
> > The PXB is composed from:
> > A primary PCI bus (can be associated with a NUMA node)
> > Acts like a normal pci bus and from the functionality point
> > of view is an "expansion" of the bus behind the
> > main host bridge.
> > A pci-2-pci bridge behind the primary PCI bus where the actual
> > devices will be attached.
> > A host-bridge PCI device
> > Situated on the bus behind the main host bridge, allows
> > the BIOS to configure the bus number and IO/mem resources.
> > It does not have its own config/data register for configuration
> > cycles, this being handled by the main host bridge.
> > A host-bridge sysbus to comply with QEMU current design.
> > Signed-off-by: Marcel Apfelbaum
> >
> > hw/pci-bridge/Makefile.objs         |   1 +
> >   hw/pci-bridge/pci_expander_bridge.c | 173 ++++++++++++++++++++++++++++++++++++
> >   include/hw/pci/pci.h                |   1 +
> >   3 files changed, 175 insertions(+)
> >   create mode 100644 hw/pci-bridge/pci_expander_bridge.c
> >
> > diff --git a/hw/pci-bridge/Makefile.objs b/hw/pci-bridge/Makefile.objs
> > index 968b369..632e442 100644
> > --- a/hw/pci-bridge/Makefile.objs
> > +++ b/hw/pci-bridge/Makefile.objs
> > @@ -1,4 +1,5 @@
> >   common-obj-y += pci_bridge_dev.o
> > +common-obj-y += pci_expander_bridge.o
> >   common-obj-y += ioh3420.o xio3130_upstream.o xio3130_downstream.o
> >   common-obj-y += i82801b11.o
> >   # NewWorld PowerMac
> > diff --git a/hw/pci-bridge/pci_expander_bridge.c b/hw/pci-bridge/pci_expander_bridge.c
> > new file mode 100644
> > index 0000000..941f3c8
> > --- /dev/null
> > +++ b/hw/pci-bridge/pci_expander_bridge.c
> > @@ -0,0 +1,173 @@
> > +/*
> > PCI Expander Bridge Device Emulation
> > Copyright (C) 2014 Red Hat Inc
> > Authors:
> > Marcel Apfelbaum
> > This work is licensed under the terms of the GNU GPL, version 2 or later.
> > See the COPYING file in the top-level directory.
> > */
> >
> > +#include "hw/pci/pci.h"
> > +#include "hw/pci/pci_bus.h"
> > +#include "hw/pci/pci_host.h"
> > +#include "hw/pci/pci_bus.h"
> > +#include "qemu/range.h"
> > +#include "qemu/error-report.h"
> >
> > +#define TYPE_PXB_BUS "pxb-bus"
> > +#define PXB_BUS(obj) OBJECT_CHECK(PXBBus, (obj), TYPE_PXB_BUS)
> >
> > +typedef struct PXBBus {
> > /*< private >*/
> > PCIBus parent_obj;
> > /*< public >*/
> > char bus_path[8];
> >
> > +} PXBBus;
> >
> > +#define TYPE_PXB_DEVICE "pxb-device"
> > +#define PXB_DEV(obj) OBJECT_CHECK(PXBDev, (obj), TYPE_PXB_DEVICE)
> >
> > +typedef struct PXBDev {
> > /*< private >*/
> > PCIDevice parent_obj;
> > /*< public >*/
> > uint8_t bus_nr;
> >
> > +} PXBDev;
> >
> > +#define TYPE_PXB_HOST "pxb-host"
> >
> > +static int pxb_bus_num(PCIBus *bus)
> > +{
> > PXBDev *pxb = PXB_DEV(bus->parent_dev);
> > return pxb->bus_nr;
> >
> > +}
> >
> > +static bool pxb_is_root(PCIBus *bus)
> > +{
> > return true; /* by definition */
> >
> > +}
> >
> > +static void pxb_bus_class_init(ObjectClass *class, void *data)
> > +{
> > PCIBusClass *pbc = PCI_BUS_CLASS(class);
> > pbc->bus_num = pxb_bus_num;
> > pbc->is_root = pxb_is_root;
> >
> > +}
> >
> > +static const TypeInfo pxb_bus_info = {
> > .name          = TYPE_PXB_BUS,
> > .parent        = TYPE_PCI_BUS,
> > .instance_size = sizeof(PXBBus),
> > .class_init    = pxb_bus_class_init,
> >
> > +};
> >
> > +static const char *pxb_host_root_bus_path(PCIHostState *host_bridge,
> >                                      PCIBus *rootbus)
> >
> > +{
> > PXBBus *bus = PXB_BUS(rootbus);
> > snprintf(bus->bus_path, 8, "0000:%02x", pxb_bus_num(rootbus));
> > return bus->bus_path;
> >
> > +}
> >
> > +static void pxb_host_class_init(ObjectClass *class, void *data)
> > +{
> > DeviceClass *dc = DEVICE_CLASS(class);
> > PCIHostBridgeClass *hc = PCI_HOST_BRIDGE_CLASS(class);
> > dc->fw_name = "pci";
> > hc->root_bus_path = pxb_host_root_bus_path;
> >
> > +}
> >
> > +static const TypeInfo pxb_host_info = {
> > .name          = TYPE_PXB_HOST,
> > .parent        = TYPE_PCI_HOST_BRIDGE,
> > .class_init    = pxb_host_class_init,
> >
> > +};
> >
> > +static int pxb_dev_initfn(PCIDevice *dev)
> > +{
> > PXBDev *pxb = PXB_DEV(dev);
> > DeviceState *ds, *bds;
> > PCIHostState *phs;
> > PCIBus *bus;
> > const char *dev_name = NULL;
> > HOST_BRIDGE_FOREACH(phs) {
> >    if (pxb->bus_nr == pci_bus_num(phs->bus)) {
> >        error_report("Bus nr %d is already used by %s.",
> >                     pxb->bus_nr, phs->bus->qbus.name);
> >        return -EINVAL;
> >    }
> > }
> > if (dev->qdev.id && *dev->qdev.id) {
> >    dev_name = dev->qdev.id;
> > }
> > ds = qdev_create(NULL, TYPE_PXB_HOST);
> > bus = pci_bus_new(ds, "pxb-internal", NULL, NULL, 0, TYPE_PXB_BUS);
> > bus->parent_dev = dev;
> > bus->address_space_mem = dev->bus->address_space_mem;
> > bus->address_space_io = dev->bus->address_space_io;
> > bus->map_irq = pci_swizzle_map_irq_fn;
> > bds = qdev_create(BUS(bus), "pci-bridge");
> > bds->id = dev_name;
> > qdev_prop_set_uint8(bds, "chassis_nr", pxb->bus_nr);
> > PCI_HOST_BRIDGE(ds)->bus = bus;
> > qdev_init_nofail(ds);
> > qdev_init_nofail(bds);
> > pci_word_test_and_set_mask(dev->config + PCI_STATUS,
> >                           PCI_STATUS_66MHZ | PCI_STATUS_FAST_BACK);
> > pci_config_set_class(dev->config, PCI_CLASS_BRIDGE_HOST);
> > return 0;
> >
> > +}
> >
> > +static Property pxb_dev_properties[] = {
> > /* Note: 0 is not a legal a PXB bus number. */
> > DEFINE_PROP_UINT8("bus_nr", PXBDev, bus_nr, 0),
> > DEFINE_PROP_END_OF_LIST(),
> >
> > +};
> >
> > +static void pxb_dev_class_init(ObjectClass *klass, void *data)
> > +{
> > DeviceClass *dc = DEVICE_CLASS(klass);
> > PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
> > k->init = pxb_dev_initfn;
> > k->vendor_id = PCI_VENDOR_ID_REDHAT;
> > k->device_id = PCI_DEVICE_ID_REDHAT_PXB;
> > k->class_id = PCI_CLASS_BRIDGE_HOST;
> > dc->desc = "PCI Expander Bridge";
> > dc->props = pxb_dev_properties;
> >
> > +}
> >
> > +static const TypeInfo pxb_dev_info = {
> > .name          = TYPE_PXB_DEVICE,
> > .parent        = TYPE_PCI_DEVICE,
> > .instance_size = sizeof(PXBDev),
> > .class_init    = pxb_dev_class_init,
> >
> > +};
> >
> > +static void pxb_register_types(void)
> > +{
> > type_register_static(&pxb_bus_info);
> > type_register_static(&pxb_host_info);
> > type_register_static(&pxb_dev_info);
> >
> > +}
> >
> > +type_init(pxb_register_types)
> > diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
> > index b7e24d4..e936528 100644
> > --- a/include/hw/pci/pci.h
> > +++ b/include/hw/pci/pci.h
> > @@ -89,6 +89,7 @@
> >   #define PCI_DEVICE_ID_REDHAT_SERIAL4     0x0004
> >   #define PCI_DEVICE_ID_REDHAT_TEST        0x0005
> >   #define PCI_DEVICE_ID_REDHAT_SDHCI       0x0007
> > +#define PCI_DEVICE_ID_REDHAT_PXB         0x0008
>
> This collides with the new PCI root device that should be in the tree by
> now :).

I'll try to keep up! :)
I'll handle it once I rebase.

Thanks,
Marcel
> Alex