[U-Boot-Users] Latest git not working for MPC8349EMDS

David Hawkins dwh at ovro.caltech.edu
Tue May 1 23:30:32 CEST 2007


Hi Michael,

> I am upgrading from 1.1.3, that shipped on the board.

Ok.

p14 of the notes comments that same version is shipped
on the MPC8349E boards.

> I am pretty confused by your notes as they relate to my image.
> For me, I am flashing at fff00000.  This is sufficient to brick
> the board :-D. It seemed like your notes were reflecting a change
> in the boot address between versions? 

see p8 comments:

   Table 1 and Figure 3 show the default Flash memory map (as shipped on
   the board), showing the location of the Linux Kernel, JFFS2/RAM disk
   filesystem, and U-Boot images [9]. This Flash memory map is used by
   the U-Boot 1.1.3 code (processor reset vector at 0xFFF00100), and the
   U-Boot 1.1.4 code, but is changed in the latest U-Boot code
   (processor reset vector at 0x00000100). Processor reset configuration
   is discussed in Section 6.

So on reset the processor reads in the HRCW and in U-Boot 1.1.3
boots from FFF00100, which happens to map to the end of Flash
(during boot). Whereas in the latest source, the Flash gets
mapped to 0 on boot and the processor executes code from 00000100.
However, once the processor is booted, the flash is mapped to
FE000000.

Confusing eh!?

> I tried to use the addresses you mention and 1) fe000000 tells me
> it is not erased, even after I erase it (?) and 2) fe700000 seems
> to have no effect.

Look at the p14, and follow along with that example, see if you
can see the right bytes in memory.

As for programming flash, look at the sequence of commands on p17.

 > I thought those were the u-boot locations for the mpc8349ITX (?).

Same processor, so same boot sequence :)

> Just to be clear, I am not even at the point of booting the kernel, just
> trying to get to the u-boot prompt of a new u-boot.

Yep. Understood.

> I really appreciate the help!  Unfortunately, I am just more confused at
> the moment.

Take the time to read the document I sent. Read the MPC8349 manual
with regards to resetting the processor. Eventually it'll make
sense. I found it confusing to start with. Hopefully this will
help you.

Cheers,
Dave









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