On Mon, Jul 6, 2026 at 9:10 PM David Lechner <[email protected]> wrote: > > On 7/6/26 8:24 AM, Carlo Caione wrote: > > U-Boot autostarts the SoC watchdog (CONFIG_WATCHDOG_AUTOSTART default > > y) and services it from its main loop, but nothing services it after > > ExitBootServices()/bootm: an EFI-booted OS that does not take over the > > watchdog in time is reset mid-boot at a wall-clock-dependent point. > > > > The MediaTek toprgu can count at most ~16 seconds, once firmware stops > > servicing it at the handoff, the OS has whatever is left of those 16 > > seconds. > > > > On the Genio 700 EVK the generic Ubuntu 26.04 arm64 image is hard-reset > > before its first boot reaches the login prompt: the mtk-wdt driver is > > a module loaded from the rootfs and cannot win that race. Nothing tells > > a generic OS that the watchdog is armed, so the failure is silent and, > > from the user's side, indistinguishable from broken firmware. > > > > Disable WATCHDOG_AUTOSTART for the Genio EVK boards (mt8365_evk > > directly, mt8188.config for the Genio 510/700). > > > > Signed-off-by: Carlo Caione <[email protected]> > > --- > > configs/mt8188.config | 1 + > > configs/mt8365_evk_defconfig | 1 + > > 2 files changed, 2 insertions(+) > > > > What about Genio 520/720 (mt8189.config) and Genio 1200 (mt8195.config)? > Seems like the same reasoning would apply to those.
Yes, but this is a preliminary patch for a much larger effort focused only on the G700 for now. Since this change essentially disables the watchdog in U-Boot I prefer to limit it, for now, only to the platforms where this is actually needed. The same will be done also for the other platforms in due time. Cheers, -- Carlo Caione
