Re: [Qemu-devel] [PATCH] xen: fix interrupt routing

[Alexander Graf]

On 26.05.2011, at 17:48, Stefano Stabellini wrote:

> xen: fix interrupt routing
> 
> - remove i440FX-xen and i440fx_write_config_xen
> we don't need to intercept pci config writes to i440FX anymore;

Why not? In which version? Did anything below change? What about compat code? 
Older hypervisor versions?

> - introduce PIIX3-xen and piix3_write_config_xen
> we do need to intercept pci config write to the PCI-ISA bridge to update
> the PCI link routing;
> 
> - set the number of PIIX3-xen interrupts lines to 128;
> 
> Signed-off-by: Stefano Stabellini <address@hidden>
> 
> diff --git a/hw/pc.h b/hw/pc.h
> index 0dcbee7..6d5730b 100644
> --- a/hw/pc.h
> +++ b/hw/pc.h
> @@ -176,7 +176,6 @@ struct PCII440FXState;
> typedef struct PCII440FXState PCII440FXState;
> 
> PCIBus *i440fx_init(PCII440FXState **pi440fx_state, int *piix_devfn, qemu_irq 
> *pic, ram_addr_t ram_size);
> -PCIBus *i440fx_xen_init(PCII440FXState **pi440fx_state, int *piix3_devfn, 
> qemu_irq *pic, ram_addr_t ram_size);
> void i440fx_init_memory_mappings(PCII440FXState *d);
> 
> /* piix4.c */
> diff --git a/hw/pc_piix.c b/hw/pc_piix.c
> index 9a22a8a..ba198de 100644
> --- a/hw/pc_piix.c
> +++ b/hw/pc_piix.c
> @@ -124,11 +124,7 @@ static void pc_init1(ram_addr_t ram_size,
>     isa_irq = qemu_allocate_irqs(isa_irq_handler, isa_irq_state, 24);
> 
>     if (pci_enabled) {
> -        if (!xen_enabled()) {
> -            pci_bus = i440fx_init(&i440fx_state, &piix3_devfn, isa_irq, 
> ram_size);
> -        } else {
> -            pci_bus = i440fx_xen_init(&i440fx_state, &piix3_devfn, isa_irq, 
> ram_size);
> -        }
> +        pci_bus = i440fx_init(&i440fx_state, &piix3_devfn, isa_irq, 
> ram_size);
>     } else {
>         pci_bus = NULL;
>         i440fx_state = NULL;
> diff --git a/hw/piix_pci.c b/hw/piix_pci.c
> index 7f1c4cc..3d73a42 100644
> --- a/hw/piix_pci.c
> +++ b/hw/piix_pci.c
> @@ -40,6 +40,7 @@ typedef PCIHostState I440FXState;
> 
> #define PIIX_NUM_PIC_IRQS       16      /* i8259 * 2 */
> #define PIIX_NUM_PIRQS          4ULL    /* PIRQ[A-D] */
> +#define XEN_PIIX_NUM_PIRQS      128ULL
> #define PIIX_PIRQC              0x60
> 
> typedef struct PIIX3State {
> @@ -78,6 +79,8 @@ struct PCII440FXState {
> #define I440FX_SMRAM    0x72
> 
> static void piix3_set_irq(void *opaque, int pirq, int level);
> +static void piix3_write_config_xen(PCIDevice *dev,
> +                               uint32_t address, uint32_t val, int len);
> 
> /* return the global irq number corresponding to a given device irq
>    pin. We could also use the bus number to have a more precise
> @@ -173,13 +176,6 @@ static void i440fx_write_config(PCIDevice *dev,
>     }
> }
> 
> -static void i440fx_write_config_xen(PCIDevice *dev,
> -                                    uint32_t address, uint32_t val, int len)
> -{
> -    xen_piix_pci_write_config_client(address, val, len);
> -    i440fx_write_config(dev, address, val, len);
> -}
> -
> static int i440fx_load_old(QEMUFile* f, void *opaque, int version_id)
> {
>     PCII440FXState *d = opaque;
> @@ -267,8 +263,17 @@ static PCIBus *i440fx_common_init(const char 
> *device_name,
>     d = pci_create_simple(b, 0, device_name);
>     *pi440fx_state = DO_UPCAST(PCII440FXState, dev, d);
> 
> -    piix3 = DO_UPCAST(PIIX3State, dev,
> -                      pci_create_simple_multifunction(b, -1, true, "PIIX3"));
> +    if (xen_enabled()) {
> +        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);

But with XEN_PIIX_NUM_PIRQS it's not a piix3 anymore, no? What's the reason 
behind this change?


Alex