On Fri, 6 Feb 2026 at 13:15, Igor Mammedov <[email protected]> wrote:
>
> Add SBSA generic watchdog to virt machine type with
> all necessary wiring for ACPI watchdog. Which includes
> setting its frequency to 1KHz (max that WDAT is able to handle).
>
> Signed-off-by: Igor Mammedov <[email protected]>
> ---
> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index 390845c503..caf5700ed2 100644
> --- a/hw/arm/virt.c
> +++ b/hw/arm/virt.c
> @@ -93,6 +93,7 @@
> #include "hw/cxl/cxl.h"
> #include "hw/cxl/cxl_host.h"
> #include "qemu/guest-random.h"
> +#include "hw/watchdog/sbsa_gwdt.h"
>
> static GlobalProperty arm_virt_compat[] = {
> { TYPE_VIRTIO_IOMMU_PCI, "aw-bits", "48" },
> @@ -194,6 +195,8 @@ static const MemMapEntry base_memmap[] = {
> [VIRT_PVTIME] = { 0x090a0000, 0x00010000 },
> [VIRT_SECURE_GPIO] = { 0x090b0000, 0x00001000 },
> [VIRT_ACPI_PCIHP] = { 0x090c0000, ACPI_PCIHP_SIZE },
> + [VIRT_GWDT_REFRESH] = { 0x090d0000, 0x00001000 },
> + [VIRT_GWDT_CONTROL] = { 0x090d1000, 0x00001000 },
> [VIRT_MMIO] = { 0x0a000000, 0x00000200 },
> /* ...repeating for a total of NUM_VIRTIO_TRANSPORTS, each of that size
> */
> [VIRT_PLATFORM_BUS] = { 0x0c000000, 0x02000000 },
> @@ -245,12 +248,32 @@ static const int a15irqmap[] = {
> [VIRT_GPIO] = 7,
> [VIRT_UART1] = 8,
> [VIRT_ACPI_GED] = 9,
> + [VIRT_GWDT_WS0] = 10,
> [VIRT_MMIO] = 16, /* ...to 16 + NUM_VIRTIO_TRANSPORTS - 1 */
> [VIRT_GIC_V2M] = 48, /* ...to 48 + NUM_GICV2M_SPIS - 1 */
> [VIRT_SMMU] = 74, /* ...to 74 + NUM_SMMU_IRQS - 1 */
> [VIRT_PLATFORM_BUS] = 112, /* ...to 112 + PLATFORM_BUS_NUM_IRQS -1 */
> };
>
> +static void create_wdt(const VirtMachineState *vms)
> +{
> + hwaddr rbase = vms->memmap[VIRT_GWDT_REFRESH].base;
> + hwaddr cbase = vms->memmap[VIRT_GWDT_CONTROL].base;
> + int irq = vms->irqmap[VIRT_GWDT_WS0];
> + DeviceState *dev = qdev_new(TYPE_WDT_SBSA);
> + SysBusDevice *s = SYS_BUS_DEVICE(dev);
> +
> + /*
> + * Set watchdog tick freq to 1Kz as it's the max WDAT driver
> + * is able to handle.
> + */
> + qdev_prop_set_uint64(dev, "clock-frequency", 1000 /* 1KHz */);
> + sysbus_realize_and_unref(s, &error_fatal);
> + sysbus_mmio_map(s, 0, rbase);
> + sysbus_mmio_map(s, 1, cbase);
> + sysbus_connect_irq(s, 0, qdev_get_gpio_in(vms->gic, irq));
> +}
Please can you also add support for exposing this device
in the device tree ?
> +
> static void create_randomness(MachineState *ms, const char *node)
> {
> struct {
> @@ -2515,6 +2538,9 @@ static void machvirt_init(MachineState *machine)
> vms->highmem_ecam &= (!firmware_loaded || aarch64);
>
> create_rtc(vms);
> + if (machine->acpi_watchdog) {
> + create_wdt(vms);
> + }
Can we have a command line option name that isn't ACPI
specific, please? There's nothing inherent to ACPI about
"I would like a watchdog device".
thanks
-- PMM
