Re: [PATCH v2 03/12] x86: add support for second ioapic

[Igor Mammedov]

On Thu,  5 Nov 2020 14:39:14 +0100
Gerd Hoffmann <kraxel@redhat.com> wrote:

> Add ioapic_init_secondary to initialize it, wire up
> in gsi handling and acpi apic table creation.
> 
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> ---
>  include/hw/i386/ioapic.h          |  1 +
>  include/hw/i386/ioapic_internal.h |  2 +-
>  include/hw/i386/x86.h             |  3 +++
>  hw/i386/acpi-common.c             | 10 ++++++++++
>  hw/i386/x86.c                     | 20 ++++++++++++++++++++
>  5 files changed, 35 insertions(+), 1 deletion(-)
> 
> diff --git a/include/hw/i386/ioapic.h b/include/hw/i386/ioapic.h
> index 59fcb158a734..1323b4b8ff6e 100644
> --- a/include/hw/i386/ioapic.h
> +++ b/include/hw/i386/ioapic.h
> @@ -22,6 +22,7 @@
>  
>  #define IOAPIC_NUM_PINS 24
>  #define IO_APIC_DEFAULT_ADDRESS 0xfec00000
> +#define IO_APIC_SECONDARY_ADDRESS (IO_APIC_DEFAULT_ADDRESS + 0x10000)
>  
>  #define TYPE_KVM_IOAPIC "kvm-ioapic"
>  #define TYPE_IOAPIC "ioapic"
> diff --git a/include/hw/i386/ioapic_internal.h 
> b/include/hw/i386/ioapic_internal.h
> index 0ac9e2400d6b..4cebd2e32c9f 100644
> --- a/include/hw/i386/ioapic_internal.h
> +++ b/include/hw/i386/ioapic_internal.h
> @@ -27,7 +27,7 @@
>  #include "qemu/notify.h"
>  #include "qom/object.h"
>  
> -#define MAX_IOAPICS                     1
> +#define MAX_IOAPICS                     2
>  
>  #define IOAPIC_LVT_DEST_SHIFT           56
>  #define IOAPIC_LVT_DEST_IDX_SHIFT       48
> diff --git a/include/hw/i386/x86.h b/include/hw/i386/x86.h
> index 739fac50871b..3f9b052cfc34 100644
> --- a/include/hw/i386/x86.h
> +++ b/include/hw/i386/x86.h
> @@ -50,6 +50,7 @@ struct X86MachineState {
>      ISADevice *rtc;
>      FWCfgState *fw_cfg;
>      qemu_irq *gsi;
> +    DeviceState *ioapic2;
>      GMappedFile *initrd_mapped_file;
>      HotplugHandler *acpi_dev;
>  
> @@ -120,10 +121,12 @@ bool x86_machine_is_acpi_enabled(const X86MachineState 
> *x86ms);
>  typedef struct GSIState {
>      qemu_irq i8259_irq[ISA_NUM_IRQS];
>      qemu_irq ioapic_irq[IOAPIC_NUM_PINS];
> +    qemu_irq ioapic2_irq[IOAPIC_NUM_PINS];
>  } GSIState;
>  
>  qemu_irq x86_allocate_cpu_irq(void);
>  void gsi_handler(void *opaque, int n, int level);
>  void ioapic_init_gsi(GSIState *gsi_state, const char *parent_name);
> +DeviceState *ioapic_init_secondary(GSIState *gsi_state);
>  
>  #endif
> diff --git a/hw/i386/acpi-common.c b/hw/i386/acpi-common.c
> index 8a769654060e..91970837bb68 100644
> --- a/hw/i386/acpi-common.c
> +++ b/hw/i386/acpi-common.c
> @@ -103,6 +103,16 @@ void acpi_build_madt(GArray *table_data, BIOSLinker 
> *linker,
>      io_apic->address = cpu_to_le32(IO_APIC_DEFAULT_ADDRESS);
>      io_apic->interrupt = cpu_to_le32(0);
>  
> +    if (x86ms->ioapic2) {
> +        AcpiMadtIoApic *io_apic2;
> +        io_apic2 = acpi_data_push(table_data, sizeof *io_apic);
> +        io_apic2->type = ACPI_APIC_IO;
> +        io_apic2->length = sizeof(*io_apic);
> +        io_apic2->io_apic_id = ACPI_BUILD_IOAPIC_ID + 1;
> +        io_apic2->address = cpu_to_le32(IO_APIC_SECONDARY_ADDRESS);
> +        io_apic2->interrupt = cpu_to_le32(24);
                                             ^^
it's no obvious where this magic number comes from.

PS:
maybe add for it a more descriptive macro 

> +    }
> +
>      if (x86ms->apic_xrupt_override) {
>          intsrcovr = acpi_data_push(table_data, sizeof *intsrcovr);
>          intsrcovr->type   = ACPI_APIC_XRUPT_OVERRIDE;
> diff --git a/hw/i386/x86.c b/hw/i386/x86.c
> index b67e7b789f89..628118e8b410 100644
> --- a/hw/i386/x86.c
> +++ b/hw/i386/x86.c
> @@ -598,6 +598,9 @@ void gsi_handler(void *opaque, int n, int level)
>      case ISA_NUM_IRQS ... IOAPIC_NUM_PINS - 1:
>          qemu_set_irq(s->ioapic_irq[n], level);
>          break;
> +    case IOAPIC_NUM_PINS ... IOAPIC_NUM_PINS * 2 - 1:
> +        qemu_set_irq(s->ioapic2_irq[n - IOAPIC_NUM_PINS], level);
> +        break;
>      }
>  }
>  
> @@ -624,6 +627,23 @@ void ioapic_init_gsi(GSIState *gsi_state, const char 
> *parent_name)
>      }
>  }
>  
> +DeviceState *ioapic_init_secondary(GSIState *gsi_state)
> +{
> +    DeviceState *dev;
> +    SysBusDevice *d;
> +    unsigned int i;
> +
> +    dev = qdev_new(TYPE_IOAPIC);
> +    d = SYS_BUS_DEVICE(dev);
> +    sysbus_realize_and_unref(d, &error_fatal);
> +    sysbus_mmio_map(d, 0, IO_APIC_SECONDARY_ADDRESS);
> +
> +    for (i = 0; i < IOAPIC_NUM_PINS; i++) {
> +        gsi_state->ioapic2_irq[i] = qdev_get_gpio_in(dev, i);
> +    }
> +    return dev;
> +}
> +
>  struct setup_data {
>      uint64_t next;
>      uint32_t type;