kernel build fails for Routerboard 450g

[Stefan Kooman]

On Mon, Jan 07, 2013 at 11:48:17PM +0100, Monthadar Al Jaberi wrote:
> Hi,
> 
> Try not using setenv. but modify the kernel config to have
> 
> machine mips mips
> 
> in the begining.

Thanks, that got it going.

I'm running into the next problem, build fails on uart:

"uart_core.o: In function `uart_bus_probe':
uart_core.c:(.text+0x3d0): undefined reference to `uart_cpu_eqres'
uart_core.c:(.text+0x3d0): relocation truncated to fit: R_MIPS_26
against `uart_cpu_eqres'
uart_subr.o: In function `uart_getenv':
uart_subr.c:(.text+0x2b8): undefined reference to `uart_bus_space_mem'
uart_subr.c:(.text+0x2bc): undefined reference to `uart_bus_space_mem'
uart_subr.c:(.text+0x2d8): undefined reference to `uart_bus_space_io'
uart_subr.c:(.text+0x2dc): undefined reference to `uart_bus_space_io'
uart_tty.o: In function `uart_cnprobe':
uart_tty.c:(.text+0x80): undefined reference to `uart_cpu_getdev'
uart_tty.c:(.text+0x80): relocation truncated to fit: R_MIPS_26 against
`uart_cpu_getdev'
*** [kernel] Error code 1
1 error
*** [buildkernel] Error code 2
1 error
*** [buildkernel] Error code 2
1 error"

If I remove "options uart" and "options gpioled" kernel builds fine. 
However, the routerboard does not boot with this kernel:

RouterBOOT booter 3.02

RouterBoard 450G

CPU frequency: 680 MHz
  Memory size: 256 MiB
      NAND size: 512 MiB

      Press any key within 2 seconds to enter setup..
      writing settings to flash... OK
      trying dhcp protocol... OK
      resolved mac address B8:27:EB:48:F3:64
      Gateway: 192.168.2.1
      transfer started ....................................... transfer
      ok, time=102.51s
      setting up elf image... OK
      jumping to kernel code

After half a minute or so the Mikrotik image gets loaded.

Any ideas on the best way to debug? 

Thanks,

Stefan