On Thu, Dec 14, 2023, at 13:52, Tudor Ambarus wrote: > On 12/14/23 12:01, Arnd Bergmann wrote: >> On Thu, Dec 14, 2023, at 11:52, Tudor Ambarus wrote: >>> +static int __init gs101_early_console_setup(struct earlycon_device *device, >> > > It works if in device tree one specifies the reg-io-width property and > sets it to 4. If the reg-io-width is not specified, the iotype defaults > to UPIO_MEM causing the SError interrupt on gs101 which makes the system > unusable. In the case of incorrect DT data like a missing reg-io-width property, I would expect it to still fail once the regular console or tty takes over from earlycon. > Also, if the earlycon comes specified from the kernel params, the > of_setup_earlycon() is no longer called and the earlycon will be set > solely based on the kernel params buffer, thus allowing users to crash > the kernel on wrong earlycon definitions. But that in turn is the same as specifying any other incorrect earlycon. > If you think the change is fine, I can amend the commit message with the > description from above. I'm still not convinced we need a special case here when everything else just requires passing the correct data. Arnd