Re: simple MPC5200B system

["Grant Likely" <grant.likely@secretlab.ca>]

On Sun, Mar 16, 2008 at 1:15 PM, Andr=E9 Schwarz
<Andre.Schwarz@matrix-vision.de> wrote:
> All,
>
>  I'm quite stuck in getting our MPC5200B based systems work on 2.6.24+
>  ... maybe someone could give me some hints.
>  Up to now the systems have been running on 2.6.19 without any problems.
>
>  This is what I've done so far :
>
>  - get a recent system with 2.6.19 running and keep the toolchain (gcc
>  4.0) including RFS uImage.
>  - latest bootloader (u-boot 1.3.2) is running fine with dtb support.
>  - Kernel and RFS images are available via bootp/tftp
>  - device tree blob seems ok, i.e. u-boot can display the blob and fill
>  in all clocks correctly.
>  - Kernel gets called with Kernel, RFS and dtb on suitable adresses
>  (0x100000, 0x600000, 0x5F0000).
>  - nothing more happens. It looks like the console isn't working properly
>  - maybe worse ...

Can you either halt the processor or reset the board and access memory
after this point?  You should see if you can access __log_buf (Look in
System.map for the address and subtract 0xc0000000 to get the physical
address).   __log_buf should give you clues about how far booting
progresses.

>  The kernel has been build using the "MPC5200 simple" setup. I've added
>  our board identifier "mv,mvbluecougar" to the list of supported boards
>  in the "mpc52xx_simple.c" file. This identifier is used in the dtb as
>  well of course. This should be enough along with a valid device tree
>  blob, isn't it ? Did I miss anything already ?

Yes, this should be enough (on a side note; it should probably be
"matrix-vision,bluecougar" unless of''mv' is your company's stock
ticker symbol).

>
>  As far as I did understand by reading the docs it should be possible
>  running a general MPC52xx kernel with a custom dtb ? Is this correct ?

That is correct.

>  The dts file has already been reduced to a minimum, i.e. only the cpu,
>  pic, xlb and a few nodes like psc1 and psc2 are present. No bestcomm,
>  pci, ata or "advanced" features like mtd partitions. All I want to get
>  working is the serial console on "/dev/ttyPSC0".

Cheers,
g.

--=20
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.