Re: [Qemu-devel] [PATCH V9 09/16] xen: add a 8259 Interrupt Controller

[Anthony Liguori <anthony@codemonkey.ws>]

On 01/25/2011 08:29 AM, anthony.perard@citrix.com wrote:
> From: Anthony PERARD<anthony.perard@citrix.com>
>
> Introduce a 8259 Interrupt Controller for target-xen; every set_irq
> call makes a Xen hypercall.
>
> Signed-off-by: Anthony PERARD<anthony.perard@citrix.com>
> Signed-off-by: Stefano Stabellini<stefano.stabellini@eu.citrix.com>
> ---
>   hw/xen_common.h     |    2 ++
>   hw/xen_machine_fv.c |    5 ++---
>   xen-all.c           |   12 ++++++++++++
>   3 files changed, 16 insertions(+), 3 deletions(-)
>
> diff --git a/hw/xen_common.h b/hw/xen_common.h
> index b98d107..0cc935a 100644
> --- a/hw/xen_common.h
> +++ b/hw/xen_common.h
> @@ -42,4 +42,6 @@ static inline int xc_fd(xc_interface *xen_xc)
>   }
>   #endif
>
> +qemu_irq *i8259_xen_init(void);
> +
>   #endif /* QEMU_HW_XEN_COMMON_H */
> diff --git a/hw/xen_machine_fv.c b/hw/xen_machine_fv.c
> index 2f51625..0a90312 100644
> --- a/hw/xen_machine_fv.c
> +++ b/hw/xen_machine_fv.c
> @@ -37,6 +37,7 @@
>   #include "xen_common.h"
>   #include "xen/hvm/hvm_info_table.h"
>   #include "xen_platform.h"
> +#include "xen_common.h"
>
>   #define MAX_IDE_BUS 2
>
> @@ -52,7 +53,6 @@ static void xen_init_fv(ram_addr_t ram_size,
>       PCIBus *pci_bus;
>       PCII440FXState *i440fx_state;
>       int piix3_devfn = -1;
> -    qemu_irq *cpu_irq;
>       qemu_irq *isa_irq;
>       qemu_irq *i8259;
>       qemu_irq *cmos_s3;
> @@ -76,8 +76,7 @@ static void xen_init_fv(ram_addr_t ram_size,
>       env = cpu_init(cpu_model);
>       env->halted = 1;
>
> -    cpu_irq = pc_allocate_cpu_irq();
> -    i8259 = i8259_init(cpu_irq[0]);
> +    i8259 = i8259_xen_init();
>       isa_irq_state = qemu_mallocz(sizeof (*isa_irq_state));
>       isa_irq_state->i8259 = i8259;
>
> diff --git a/xen-all.c b/xen-all.c
> index 8a51873..205cbc4 100644
> --- a/xen-all.c
> +++ b/xen-all.c
> @@ -43,6 +43,18 @@ void xen_piix_pci_write_config_client(uint32_t address, uint32_t val, int len)
>       }
>   }
>
> +/* i8259 */
> +
> +static void i8259_set_irq(void *opaque, int irq, int level)
> +{
> +    xc_hvm_set_isa_irq_level(xen_xc, xen_domid, irq, level);
> +}
> +
> +qemu_irq *i8259_xen_init(void)
> +{
> +    return qemu_allocate_irqs(i8259_set_irq, NULL, 16);
> +}
> +
>    


I think it would make more sense to just call it a Xen interrupt 
controller as it's clearly not an i8259.  Xen may emulate an i8259 in 
the kernel but this has nothing to do with that AFAIK.

Regards,

Anthony Liguori

>   /* Initialise Xen */
>
>   int xen_init(int smp_cpus)
>