Re: [Qemu-devel] [PATCH RFC V3 05/12] piix_pci: Introduces Xen specific call for irq.

[Isaku Yamahata]

On Fri, Sep 17, 2010 at 12:15:00PM +0100, address@hidden wrote:
> From: Anthony PERARD <address@hidden>
> 
> This patch introduces Xen specific call in piix_pci.
> 
> The specific part for Xen is in write_config, set_irq and get_pirq.
> 
> Signed-off-by: Anthony PERARD <address@hidden>
> Signed-off-by: Stefano Stabellini <address@hidden>
> ---
>  hw/piix_pci.c |   10 +++++++++-
>  hw/xen.h      |    6 ++++++
>  xen-all.c     |   29 +++++++++++++++++++++++++++++
>  xen-stub.c    |   13 +++++++++++++
>  4 files changed, 57 insertions(+), 1 deletions(-)
> 
> diff --git a/hw/piix_pci.c b/hw/piix_pci.c
> index f152a0f..41a342f 100644
> --- a/hw/piix_pci.c
> +++ b/hw/piix_pci.c
> @@ -28,6 +28,7 @@
>  #include "pci_host.h"
>  #include "isa.h"
>  #include "sysbus.h"
> +#include "xen.h"
>  
>  /*
>   * I440FX chipset data sheet.
> @@ -142,6 +143,9 @@ static void i440fx_write_config(PCIDevice *dev,
>  {
>      PCII440FXState *d = DO_UPCAST(PCII440FXState, dev, dev);
>  
> +    if (xen_enabled())
> +        xen_piix_pci_write_config_client(address, val, len);
> +
>      /* XXX: implement SMRAM.D_LOCK */
>      pci_default_write_config(dev, address, val, len);
>      if (ranges_overlap(address, len, I440FX_PAM, I440FX_PAM_SIZE) ||

Maybe I wasn't clear enough. This dynamic check can also be eliminated.
Something like the following pseudo code.

i440fx_init()
        ...
        if (xen_enabled) {
                d = pci_create_simple(b, 0, "i440FX-xen");
        } else }
                d = pci_create_simple(b, 0, "i440FX");
        }


static PCIDeviceInfo i440fx_info[] = {
    {
        .qdev.name    = "i440FX",
        ...
        .config_write = i440fx_write_config,
    },{
        .qdev.name    = "i440FX-xen",
        ...
        .config_write = i440fx_write_config_xen,
    },{


i440fx_write_config_xen()
{
        xen_piix_pci_write_config_client();
        i440fx_write_config()
}




> @@ -235,7 +239,11 @@ PCIBus *i440fx_init(PCII440FXState **pi440fx_state, int 
> *piix3_devfn, qemu_irq *
>      piix3 = DO_UPCAST(PIIX3State, dev,
>                        pci_create_simple_multifunction(b, -1, true, "PIIX3"));
>      piix3->pic = pic;
> -    pci_bus_irqs(b, piix3_set_irq, pci_slot_get_pirq, piix3, 4);
> +    if (xen_enabled()) {
> +        pci_bus_irqs(b, xen_piix3_set_irq, xen_pci_slot_get_pirq, piix3, 4);
> +    } else {
> +        pci_bus_irqs(b, piix3_set_irq, pci_slot_get_pirq, piix3, 4);
> +    }
>      (*pi440fx_state)->piix3 = piix3;
>  
>      *piix3_devfn = piix3->dev.devfn;
> diff --git a/hw/xen.h b/hw/xen.h
> index 14bbb6e..c5189b1 100644
> --- a/hw/xen.h
> +++ b/hw/xen.h
> @@ -8,6 +8,8 @@
>   */
>  #include <inttypes.h>
>  
> +#include "qemu-common.h"
> +
>  /* xen-machine.c */
>  enum xen_mode {
>      XEN_EMULATE = 0,  // xen emulation, using xenner (default)
> @@ -26,6 +28,10 @@ extern int xen_allowed;
>  #define xen_enabled() (0)
>  #endif
>  
> +int xen_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num);
> +void xen_piix3_set_irq(void *opaque, int irq_num, int level);
> +void xen_piix_pci_write_config_client(uint32_t address, uint32_t val, int 
> len);
> +
>  int xen_init(int smp_cpus);
>  
>  #endif /* QEMU_HW_XEN_H */
> diff --git a/xen-all.c b/xen-all.c
> index f505563..948e439 100644
> --- a/xen-all.c
> +++ b/xen-all.c
> @@ -8,9 +8,38 @@
>  
>  #include "config.h"
>  
> +#include "hw/pci.h"
>  #include "hw/xen_common.h"
>  #include "hw/xen_backend.h"
>  
> +/* Xen specific function for piix pci */
> +
> +int xen_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num)
> +{
> +    return irq_num + ((pci_dev->devfn >> 3) << 2);
> +}
> +
> +void xen_piix3_set_irq(void *opaque, int irq_num, int level)
> +{
> +    xc_hvm_set_pci_intx_level(xen_xc, xen_domid, 0, 0, irq_num >> 2,
> +                              irq_num & 3, level);
> +}
> +
> +void xen_piix_pci_write_config_client(uint32_t address, uint32_t val, int 
> len)
> +{
> +    int i;
> +
> +    /* Scan for updates to PCI link routes (0x60-0x63). */
> +    for (i = 0; i < len; i++) {
> +        uint8_t v = (val >> (8*i)) & 0xff;
> +        if (v & 0x80)
> +            v = 0;
> +        v &= 0xf;
> +        if (((address+i) >= 0x60) && ((address+i) <= 0x63))
> +            xc_hvm_set_pci_link_route(xen_xc, xen_domid, address + i - 0x60, 
> v);
> +    }
> +}
> +
>  /* Initialise Xen */
>  
>  int xen_init(int smp_cpus)
> diff --git a/xen-stub.c b/xen-stub.c
> index 0fa9c51..07e64bc 100644
> --- a/xen-stub.c
> +++ b/xen-stub.c
> @@ -11,6 +11,19 @@
>  #include "qemu-common.h"
>  #include "hw/xen.h"
>  
> +int xen_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num)
> +{
> +    return -1;
> +}
> +
> +void xen_piix3_set_irq(void *opaque, int irq_num, int level)
> +{
> +}
> +
> +void xen_piix_pci_write_config_client(uint32_t address, uint32_t val, int 
> len)
> +{
> +}
> +
>  int xen_init(int smp_cpus)
>  {
>      return -ENOSYS;
> -- 
> 1.6.5
> 
> 

-- 
yamahata