[Qemu-devel] Re: [PATCH 09/10] pci: set PCI multi-function bit appropriately.

[Michael S. Tsirkin]

On Thu, Jun 17, 2010 at 03:15:51PM +0900, Isaku Yamahata wrote:
> set PCI multi-function bit appropriately.
> 
> Signed-off-by: Isaku Yamahata <address@hidden>
> 
> ---
> changes v1 -> v2:
> don't set header type register in configuration space.
> ---
>  hw/pci.c |   25 +++++++++++++++++++++++++
>  1 files changed, 25 insertions(+), 0 deletions(-)
> 
> diff --git a/hw/pci.c b/hw/pci.c
> index 5316aa5..ee391dc 100644
> --- a/hw/pci.c
> +++ b/hw/pci.c
> @@ -607,6 +607,30 @@ static void pci_init_wmask_bridge(PCIDevice *d)
>      pci_set_word(d->wmask + PCI_BRIDGE_CONTROL, 0xffff);
>  }
>  
> +static void pci_init_multifunction(PCIBus *bus, PCIDevice *dev)
> +{
> +    uint8_t slot = PCI_SLOT(dev->devfn);
> +    uint8_t func_max = 8;

enum or define would be better

> +    uint8_t func;

If I understand correctly what this does, it goes over
other functions of the same device, and sets the MULTI_FUNCTION bit
for them if there's more than one function.
Instead, why don't we just set PCI_HEADER_TYPE_MULTI_FUNCTION
in relevant devices?

> +
> +    for (func = 0; func < func_max; ++func) {
> +        if (bus->devices[PCI_DEVFN(slot, func)]) {
> +            break;
> +        }
> +    }
> +    if (func == func_max) {
> +        return;
> +    }
> +

The above only works if the function is called before
device is added to bus.

> +    for (func = 0; func < func_max; ++func) {
> +        if (bus->devices[PCI_DEVFN(slot, func)]) {
> +            bus->devices[PCI_DEVFN(slot, func)]->config[PCI_HEADER_TYPE] |=
> +                PCI_HEADER_TYPE_MULTI_FUNCTION;
> +        }
> +    }
> +    dev->config[PCI_HEADER_TYPE] |= PCI_HEADER_TYPE_MULTI_FUNCTION;

Isn't the bit set above already?

> +}
> +
>  static void pci_config_alloc(PCIDevice *pci_dev)
>  {
>      int config_size = pci_config_size(pci_dev);
> @@ -660,6 +684,7 @@ static PCIDevice *do_pci_register_device(PCIDevice 
> *pci_dev, PCIBus *bus,
>      if (is_bridge) {
>          pci_init_wmask_bridge(pci_dev);
>      }
> +    pci_init_multifunction(bus, pci_dev);
>  
>      if (!config_read)
>          config_read = pci_default_read_config;
> -- 
> 1.6.6.1