Re: [PATCH v5 2/4] hw/riscv/virt: Add acpi ged support

[Igor Mammedov <imammedo@redhat.com>]

On Wed, 4 Feb 2026 18:23:49 +0800 (CST)
<liu.xuemei1@zte.com.cn> wrote:

> From: Xuemei Liu <liu.xuemei1@zte.com.cn>
> 
> This patch adds ACPI Generic Event Device (GED) support to
> the RISC-V virt machine.
> 
> Co-authored-by: Björn Töpel <bjorn@rivosinc.com>
> Signed-off-by: Xuemei Liu <liu.xuemei1@zte.com.cn>
> ---
>  hw/riscv/Kconfig           |  1 +
>  hw/riscv/virt-acpi-build.c |  8 ++++++++
>  hw/riscv/virt.c            | 23 +++++++++++++++++++++++
>  include/hw/riscv/virt.h    |  3 +++
>  4 files changed, 35 insertions(+)
> 
> diff --git a/hw/riscv/Kconfig b/hw/riscv/Kconfig
> index 0222c93f87..3dad43669f 100644
> --- a/hw/riscv/Kconfig
> +++ b/hw/riscv/Kconfig
> @@ -68,6 +68,7 @@ config RISCV_VIRT
>      select PLATFORM_BUS
>      select ACPI
>      select ACPI_PCI
> +    select ACPI_HW_REDUCED
> 
>  config SHAKTI_C
>      bool
> diff --git a/hw/riscv/virt-acpi-build.c b/hw/riscv/virt-acpi-build.c
> index f1406cb683..07d1024316 100644
> --- a/hw/riscv/virt-acpi-build.c
> +++ b/hw/riscv/virt-acpi-build.c
> @@ -27,6 +27,7 @@
>  #include "hw/acpi/acpi-defs.h"
>  #include "hw/acpi/acpi.h"
>  #include "hw/acpi/aml-build.h"
> +#include "hw/acpi/generic_event_device.h"
>  #include "hw/acpi/pci.h"
>  #include "hw/acpi/utils.h"
>  #include "hw/intc/riscv_aclint.h"
> @@ -498,6 +499,13 @@ static void build_dsdt(GArray *table_data,
>          acpi_dsdt_add_gpex_host(scope, PCIE_IRQ + VIRT_IRQCHIP_NUM_SOURCES * 2);
>      }
> 
> +    if (s->acpi_ged) {
is this check necessary?
You probably won't get here at all if acpi is not enabled
and in hunk below you always create GED if acpi is enabled

other than that LGTM

> +        build_ged_aml(scope, "\\_SB."GED_DEVICE,
> +                      HOTPLUG_HANDLER(s->acpi_ged),
> +                      ACPI_GED_IRQ, AML_SYSTEM_MEMORY,
> +                      s->memmap[VIRT_ACPI_GED].base);
> +    }
> +
>      aml_append(dsdt, scope);
> 
>      /* copy AML table into ACPI tables blob and patch header there */
> diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
> index bd8608ea5b..1d7011b952 100644
> --- a/hw/riscv/virt.c
> +++ b/hw/riscv/virt.c
> @@ -55,6 +55,7 @@
>  #include "hw/pci-host/gpex.h"
>  #include "hw/display/ramfb.h"
>  #include "hw/acpi/aml-build.h"
> +#include "hw/acpi/generic_event_device.h"
>  #include "qapi/qapi-visit-common.h"
>  #include "hw/virtio/virtio-iommu.h"
>  #include "hw/uefi/var-service-api.h"
> @@ -95,6 +96,7 @@ static const MemMapEntry virt_memmap[] = {
>      [VIRT_UART0] =        { 0x10000000,         0x100 },
>      [VIRT_VIRTIO] =       { 0x10001000,        0x1000 },
>      [VIRT_FW_CFG] =       { 0x10100000,          0x18 },
> +    [VIRT_ACPI_GED] =     { 0x10101000, ACPI_GED_EVT_SEL_LEN },
>      [VIRT_FLASH] =        { 0x20000000,     0x4000000 },
>      [VIRT_IMSIC_M] =      { 0x24000000, VIRT_IMSIC_MAX_SIZE },
>      [VIRT_IMSIC_S] =      { 0x28000000, VIRT_IMSIC_MAX_SIZE },
> @@ -1270,6 +1272,22 @@ static inline DeviceState *gpex_pcie_init(MemoryRegion *sys_mem,
>      return dev;
>  }
> 
> +static DeviceState *create_acpi_ged(RISCVVirtState *s, DeviceState *irqchip)
> +{
> +    DeviceState *dev;
> +    uint32_t event = ACPI_GED_PWR_DOWN_EVT;
> +
> +    dev = qdev_new(TYPE_ACPI_GED);
> +    qdev_prop_set_uint32(dev, "ged-event", event);
> +    sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
> +
> +    sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, s->memmap[VIRT_ACPI_GED].base);
> +    sysbus_connect_irq(SYS_BUS_DEVICE(dev), 0,
> +                       qdev_get_gpio_in(irqchip, ACPI_GED_IRQ));
> +
> +    return dev;
> +}
> +
>  static FWCfgState *create_fw_cfg(const MachineState *ms, hwaddr base)
>  {
>      FWCfgState *fw_cfg;
> @@ -1702,6 +1720,11 @@ static void virt_machine_init(MachineState *machine)
> 
>      create_platform_bus(s, mmio_irqchip);
> 
> +    /* acpi ged */
> +    if (virt_is_acpi_enabled(s)) {
> +        s->acpi_ged = create_acpi_ged(s, mmio_irqchip);
> +    }
> +
>      serial_mm_init(system_memory, s->memmap[VIRT_UART0].base,
>          0, qdev_get_gpio_in(mmio_irqchip, UART0_IRQ), 399193,
>          serial_hd(0), DEVICE_LITTLE_ENDIAN);
> diff --git a/include/hw/riscv/virt.h b/include/hw/riscv/virt.h
> index 18a2a323a3..9ea0b3b7b6 100644
> --- a/include/hw/riscv/virt.h
> +++ b/include/hw/riscv/virt.h
> @@ -47,6 +47,7 @@ struct RISCVVirtState {
> 
>      /*< public >*/
>      Notifier machine_done;
> +    DeviceState *acpi_ged;
>      DeviceState *platform_bus_dev;
>      RISCVHartArrayState soc[VIRT_SOCKETS_MAX];
>      DeviceState *irqchip[VIRT_SOCKETS_MAX];
> @@ -88,9 +89,11 @@ enum {
>      VIRT_PLATFORM_BUS,
>      VIRT_PCIE_ECAM,
>      VIRT_IOMMU_SYS,
> +    VIRT_ACPI_GED,
>  };
> 
>  enum {
> +    ACPI_GED_IRQ = 9,
>      UART0_IRQ = 10,
>      RTC_IRQ = 11,
>      VIRTIO_IRQ = 1, /* 1 to 8 */