I am currently seeing failed secure boot with modified partition layout which ends up in this kind of error on very early phase on the boot: " ERROR: Highest Layer Module = 0x1d, Lowest Layer Module = 0x1d, Aux Info = 0x0, Reason = 0x8". Flashing and signing process are working ok, atleast from tegraflash point of view and on device side, there is no errors on flashing process.
When flashing signed firmware (with modified partition layout), device ends up in boot loop with above mentioned error message.
With unchanged partition map device boots up ok.
Is there more detailed document about boot errors?