Re: [PATCH 3/4] microvm: add second ioapic

[Igor Mammedov <imammedo@redhat.com>]

On Fri, 16 Oct 2020 13:43:27 +0200
Gerd Hoffmann <kraxel@redhat.com> wrote:

> Add more IRQ lines.  Depends on ACPI.
> Also enable this only with userspace ioapic,
> not sure whenever the kernel can handle two ioapics.
> 
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

For ACPI part:
Reviewed-by: Igor Mammedov <imammedo@redhat.com>

> ---
>  include/hw/i386/ioapic_internal.h |  2 +-
>  include/hw/i386/x86.h             |  1 +
>  hw/i386/acpi-common.c             | 10 ++++++++++
>  hw/i386/microvm.c                 | 30 ++++++++++++++++++++++++++++--
>  4 files changed, 40 insertions(+), 3 deletions(-)
> 
> 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 bfa9cb2a258b..6da57033a875 100644
> --- a/include/hw/i386/x86.h
> +++ b/include/hw/i386/x86.h
> @@ -120,6 +120,7 @@ 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);
> diff --git a/hw/i386/acpi-common.c b/hw/i386/acpi-common.c
> index 8a769654060e..f0689392a39f 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 (object_property_find(OBJECT(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_DEFAULT_ADDRESS + 0x10000);
> +        io_apic2->interrupt = cpu_to_le32(24);
> +    }
> +
>      if (x86ms->apic_xrupt_override) {
>          intsrcovr = acpi_data_push(table_data, sizeof *intsrcovr);
>          intsrcovr->type   = ACPI_APIC_XRUPT_OVERRIDE;
> diff --git a/hw/i386/microvm.c b/hw/i386/microvm.c
> index 638e95c39e8c..15c3e078a4aa 100644
> --- a/hw/i386/microvm.c
> +++ b/hw/i386/microvm.c
> @@ -99,7 +99,11 @@ static void microvm_gsi_handler(void *opaque, int n, int level)
>  {
>      GSIState *s = opaque;
>  
> -    qemu_set_irq(s->ioapic_irq[n], level);
> +    if (n >= 24) {
> +        qemu_set_irq(s->ioapic2_irq[n - 24], level);
> +    } else {
> +        qemu_set_irq(s->ioapic_irq[n], level);
> +    }
>  }
>  
>  static void create_gpex(MicrovmMachineState *mms)
> @@ -157,6 +161,7 @@ static void microvm_devices_init(MicrovmMachineState *mms)
>      ISABus *isa_bus;
>      ISADevice *rtc_state;
>      GSIState *gsi_state;
> +    bool ioapic2 = false;
>      int i;
>  
>      /* Core components */
> @@ -165,8 +170,13 @@ static void microvm_devices_init(MicrovmMachineState *mms)
>      if (mms->pic == ON_OFF_AUTO_ON || mms->pic == ON_OFF_AUTO_AUTO) {
>          x86ms->gsi = qemu_allocate_irqs(gsi_handler, gsi_state, GSI_NUM_PINS);
>      } else {
> +        int pins = GSI_NUM_PINS;
> +        if (!kvm_ioapic_in_kernel() && x86_machine_is_acpi_enabled(x86ms)) {
> +            ioapic2 = true;
> +            pins += 24;
> +        }
>          x86ms->gsi = qemu_allocate_irqs(microvm_gsi_handler,
> -                                        gsi_state, GSI_NUM_PINS);
> +                                        gsi_state, pins);
>      }
>  
>      isa_bus = isa_bus_new(NULL, get_system_memory(), get_system_io(),
> @@ -175,6 +185,22 @@ static void microvm_devices_init(MicrovmMachineState *mms)
>  
>      ioapic_init_gsi(gsi_state, "machine");
>  
> +    if (ioapic2) {
> +        DeviceState *dev;
> +        SysBusDevice *d;
> +        unsigned int i;
> +
> +        dev = qdev_new(TYPE_IOAPIC);
> +        object_property_add_child(OBJECT(mms), "ioapic2", OBJECT(dev));
> +        d = SYS_BUS_DEVICE(dev);
> +        sysbus_realize_and_unref(d, &error_fatal);
> +        sysbus_mmio_map(d, 0, IO_APIC_DEFAULT_ADDRESS + 0x10000);
> +
> +        for (i = 0; i < IOAPIC_NUM_PINS; i++) {
> +            gsi_state->ioapic2_irq[i] = qdev_get_gpio_in(dev, i);
> +        }
> +    }
> +
>      kvmclock_create(true);
>  
>      mms->virtio_irq_base = 5;