Re: Hitting WARN_ON_ONCE in i2c-designware-common.c

[Jarkko Nikula]

Hi

On 4/15/25 3:03 PM, Jesper Dangaard Brouer wrote:
> Hi Maintainers,
>
> I'm hitting a WARN_ON_ONCE in drivers/i2c/busses/i2c-designware-common.c
> when booting the kernel on our Gen12 hardware.
>
> I'm using devel kernel net-next at commit 1a9239bb425 (merge tag 'net- 
> next-6.15').
Is this a regression so was this working before?

Support for this platform was added back in 2016 by the commit 
e4e666ba74d4 ("i2c: designware: Add device HID for future AMD I2C 
controller").

> [   10.062651] i2c_designware AMDI0010:00: Unknown Synopsys component 
> type: 0xffffffff
> [   10.073312] pps_core: LinuxPPS API ver. 1 registered
> [   10.073372] piix4_smbus 0000:00:14.0: SMBus Host Controller at 0xb00, 
> revision 0
> [   10.075433] i2c_designware AMDI0010:01: Unknown Synopsys component 
> type: 0xffffffff

These "Unknown Synopsys component type: 0xffffffff" errors indicate IP 
is not alive. Perhaps linked to the missing clock or not powered.