Hi Masahiro, On 31 August 2014 20:06, Masahiro Yamada <yamad...@jp.panasonic.com> wrote: > We have not had a good method to debug the early boot stage such as > lowlevel_init function. I guess developers generally use dedicated > debuggers for that, but it is difficult in some cases. > (For example, my debugger cannot connect to the ARM processor when > it is in the secure state. It sometimes happens when I need to > debug the early boot stage on ARM SoCs with secure extension.) > > The low level debug feature in Linux would be also helpful for U-boot > when we are stucking in nasty problems where the console is not > available yet. > > You have to enable CONFIG_DEBUG_LL to use this feature. > For now, only 8250-compatible UART devices are supported. > You can add a header file under arch/arm/include/debug/ directory > to support your UART device if necessary. > > Signed-off-by: Masahiro Yamada <yamad...@jp.panasonic.com>
Is it possible to use the existing drivers for this? It seems unfortunate to duplicate the ns16550 driver (if that is what has happened). E.g. I have had good luck just calling that driver code directly. I'm not sure of an overall framework but it must be possible... Regards, Simon _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
