Re: [Qemu-devel] [PATCH 4/6] pci: add helper to retrieve the 64-bit range

[Igor Mammedov]

On Wed, 4 Sep 2013 13:48:37 +0300
"Michael S. Tsirkin" <m...@redhat.com> wrote:

> Signed-off-by: Michael S. Tsirkin <m...@redhat.com>
> ---
>  include/hw/pci/pci.h |  1 +
>  hw/pci/pci.c         | 43 +++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 44 insertions(+)
> 
> diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
> index 2374aa9..7be93ae 100644
> --- a/include/hw/pci/pci.h
> +++ b/include/hw/pci/pci.h
> @@ -397,6 +397,7 @@ const char *pci_root_bus_path(PCIDevice *dev);
>  PCIDevice *pci_find_device(PCIBus *bus, int bus_num, uint8_t devfn);
>  int pci_qdev_find_device(const char *id, PCIDevice **pdev);
>  PCIBus *pci_get_bus_devfn(int *devfnp, PCIBus *root, const char *devaddr);
> +void pci_bus_get_w64_range(PCIBus *bus, Range *range);
>  
>  int pci_parse_devaddr(const char *addr, int *domp, int *busp,
>                        unsigned int *slotp, unsigned int *funcp);
> diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> index 8c33352..d9f9bdf 100644
> --- a/hw/pci/pci.c
> +++ b/hw/pci/pci.c
> @@ -2257,6 +2257,49 @@ void pci_setup_iommu(PCIBus *bus, PCIIOMMUFunc fn, 
> void *opaque)
>      bus->iommu_opaque = opaque;
>  }
>  
> +static void pci_dev_get_w64(PCIBus *b, PCIDevice *dev, void *opaque)
> +{
> +    Range *range = opaque;
> +    PCIDeviceClass *pc = PCI_DEVICE_GET_CLASS(dev);
> +    uint16_t cmd = pci_get_word(dev->config + PCI_COMMAND);
> +    int r;
> +
> +    if (!(cmd & PCI_COMMAND_MEMORY)) {
> +        return;
> +    }
> +
> +    if (pc->is_bridge) {
> +        pcibus_t base = pci_bridge_get_base(dev, 
> PCI_BASE_ADDRESS_MEM_PREFETCH);
what guaranties that 'base' won't be below 4Gb and be above '4Gb + 
above_4g_mem_size'?

> +        pcibus_t limit = pci_bridge_get_limit(dev, 
> PCI_BASE_ADDRESS_MEM_PREFETCH);
> +
> +        if (limit >= base) {
> +            Range pref_range;
> +            pref_range.begin = base;
> +            pref_range.end = limit + 1;
> +            range_extend(range, &pref_range);
> +        }
> +    }
> +    for (r = 0; r < PCI_NUM_REGIONS; ++r) {
> +        PCIIORegion *region = &dev->io_regions[r];
> +        Range region_range;
> +
> +        if (!region->size ||
> +            (region->type & PCI_BASE_ADDRESS_SPACE_IO) ||
> +            !(region->type & PCI_BASE_ADDRESS_MEM_TYPE_64)) {
> +            continue;
> +        }
> +        region_range.begin = pci_get_quad(dev->config + pci_bar(dev, r));
> +        region_range.end = region_range.begin + region->size;
> +        range_extend(range, &region_range);
> +    }
> +}
> +
> +void pci_bus_get_w64_range(PCIBus *bus, Range *range)
> +{
> +    range->begin = range->end = 0;
> +    pci_for_each_device_under_bus(bus, pci_dev_get_w64, range);
> +}
> +
>  static const TypeInfo pci_device_type_info = {
>      .name = TYPE_PCI_DEVICE,
>      .parent = TYPE_DEVICE,