Re: [Qemu-devel] [PATCH 3/4] xen:hw:pci-host:piix: introduce xen_igd_i440fx_init

["Chen, Tiejun" <tiejun.chen@intel.com>]

On 2014/7/29 19:19, Michael S. Tsirkin wrote:
> On Thu, Jul 24, 2014 at 07:30:28PM +0800, Tiejun Chen wrote:
>> This is almost same as an original i440fx_init but just
>> work with that xen igd host bridge to passthrough.
>>
>> Signed-off-by: Tiejun Chen <tiejun.chen@intel.com>
>> ---
>>   hw/pci-host/piix.c   | 79 ++++++++++++++++++++++++++++++++++++++++++++++++++++
>>   include/hw/i386/pc.h | 10 +++++++
>>   2 files changed, 89 insertions(+)
>>
>> diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c
>> index 9feddf5..7ef08d7 100644
>> --- a/hw/pci-host/piix.c
>> +++ b/hw/pci-host/piix.c
>> @@ -407,6 +407,85 @@ PCIBus *i440fx_init(PCII440FXState **pi440fx_state,
>>       return b;
>>   }
>>
>> +PCIBus *xen_igd_i440fx_init(PCII440FXState **pi440fx_state,
>> +                    int *piix3_devfn,
>> +                    ISABus **isa_bus, qemu_irq *pic,
>> +                    MemoryRegion *address_space_mem,
>> +                    MemoryRegion *address_space_io,
>> +                    ram_addr_t ram_size,
>> +                    ram_addr_t below_4g_mem_size,
>> +                    ram_addr_t above_4g_mem_size,
>> +                    MemoryRegion *pci_address_space,
>> +                    MemoryRegion *ram_memory)
>> +{
>> +    DeviceState *dev;
>> +    PCIBus *b;
>> +    PCIDevice *d;
>> +    PCIHostState *s;
>> +    PIIX3State *piix3;
>> +    PCII440FXState *f;
>> +    unsigned i;
>> +    I440FXState *i440fx;
>> +
>> +    dev = qdev_create(NULL, TYPE_I440FX_PCI_HOST_BRIDGE);
>> +    s = PCI_HOST_BRIDGE(dev);
>> +    b = pci_bus_new(dev, NULL, pci_address_space,
>> +                    address_space_io, 0, TYPE_PCI_BUS);
>> +    s->bus = b;
>> +    object_property_add_child(qdev_get_machine(), "i440fx", OBJECT(dev), NULL);
>> +    qdev_init_nofail(dev);
>> +
>> +    d = pci_create_simple(b, 0, TYPE_I440FX_XEN_PCI_DEVICE);
>> +    *pi440fx_state = I440FX_XEN_PCI_DEVICE(d);
>> +    f = *pi440fx_state;
>> +    f->system_memory = address_space_mem;
>> +    f->pci_address_space = pci_address_space;
>> +    f->ram_memory = ram_memory;
>> +
>> +    i440fx = I440FX_PCI_HOST_BRIDGE(dev);
>> +    i440fx->pci_info.w32.begin = below_4g_mem_size;
>> +
>> +    /* setup pci memory mapping */
>> +    pc_pci_as_mapping_init(OBJECT(f), f->system_memory,
>> +                           f->pci_address_space);
>> +
>> +    memory_region_init_alias(&f->smram_region, OBJECT(d), "smram-region",
>> +                             f->pci_address_space, 0xa0000, 0x20000);
>> +    memory_region_add_subregion_overlap(f->system_memory, 0xa0000,
>> +                                        &f->smram_region, 1);
>> +    memory_region_set_enabled(&f->smram_region, false);
>> +    init_pam(dev, f->ram_memory, f->system_memory, f->pci_address_space,
>> +             &f->pam_regions[0], PAM_BIOS_BASE, PAM_BIOS_SIZE);
>> +    for (i = 0; i < 12; ++i) {
>> +        init_pam(dev, f->ram_memory, f->system_memory, f->pci_address_space,
>> +                 &f->pam_regions[i+1], PAM_EXPAN_BASE + i * PAM_EXPAN_SIZE,
>> +                 PAM_EXPAN_SIZE);
>> +    }
>> +
>> +    /* Xen supports additional interrupt routes from the PCI devices to
>> +     * the IOAPIC: the four pins of each PCI device on the bus are also
>> +     * connected to the IOAPIC directly.
>> +     * These additional routes can be discovered through ACPI. */
>> +    piix3 = DO_UPCAST(PIIX3State, dev,
>> +            pci_create_simple_multifunction(b, -1, true, "PIIX3-xen"));
>> +    pci_bus_irqs(b, xen_piix3_set_irq, xen_pci_slot_get_pirq,
>> +            piix3, XEN_PIIX_NUM_PIRQS);
>> +    piix3->pic = pic;
>> +    *isa_bus = ISA_BUS(qdev_get_child_bus(DEVICE(piix3), "isa.0"));
>> +
>> +    *piix3_devfn = piix3->dev.devfn;
>> +
>> +    ram_size = ram_size / 8 / 1024 / 1024;
>> +    if (ram_size > 255) {
>> +        ram_size = 255;
>> +    }
>> +    d->config[0x57] = ram_size;
>> +
>> +    i440fx_update_memory_mappings(f);
>> +
>> +    return b;
>> +}
>
> Too much copy-paste. Please refactor to avoid code duplication.

Okay.

> Is the only difference here the use of TYPE_I440FX_XEN_PCI_DEVICE?

Yes.

> Then you can pass type in as a parameter to a common static sub-function.

I'm fine but as I remember Paolo don't like we intervene a common 
function. And we'll introduce something specific to IGD, like that faked 
PCIe device.

Thanks
Tiejun

>
>> +
>>   PCIBus *find_i440fx(void)
>>   {
>>       PCIHostState *s = OBJECT_CHECK(PCIHostState,
>> diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
>> index 1c0c382..51656d9 100644
>> --- a/include/hw/i386/pc.h
>> +++ b/include/hw/i386/pc.h
>> @@ -239,6 +239,16 @@ PCIBus *i440fx_init(PCII440FXState **pi440fx_state, int *piix_devfn,
>>                       MemoryRegion *pci_memory,
>>                       MemoryRegion *ram_memory);
>>
>> +PCIBus *xen_igd_i440fx_init(PCII440FXState **pi440fx_state, int *piix_devfn,
>> +                    ISABus **isa_bus, qemu_irq *pic,
>> +                    MemoryRegion *address_space_mem,
>> +                    MemoryRegion *address_space_io,
>> +                    ram_addr_t ram_size,
>> +                    ram_addr_t below_4g_mem_size,
>> +                    ram_addr_t above_4g_mem_size,
>> +                    MemoryRegion *pci_memory,
>> +                    MemoryRegion *ram_memory);
>> +
>>   PCIBus *find_i440fx(void);
>>   /* piix4.c */
>>   extern PCIDevice *piix4_dev;
>> --
>> 1.9.1
>
>