[U-Boot] MPC8349E-MDS questions

[David Hawkins <dwh@ovro.caltech.edu>]

David Hawkins wrote:
> Hi Mit Matelske,
> 
>> I believe I made the changes to our FPGA that the eval's CPLD did when
>> the FCFG gets switched to 1 (bringing up flash enable at reset).
>> Since we have a smaller flash, I am putting the u-boot.bin at
>> 0xFFE00000 (0xFFF00000 for the original Freescale u-boot), the base
>> address for our flash.  But I'm still not having any luck.
> 
> Look at p33 for a logic analyzer power-on reset trace:
> http://www.ovro.caltech.edu/~dwh/carma_board/powerpc_mpc8349e.pdf
> 
> When your board boots, assuming you have the configuration
> reset words pin strapping set to read from the local bus,
> the processor will read the RCWs starting from 'address zero'
> on CS#0, i.e., from the beginning of your flash.
> 
> If you have BMS = 0, then the reset vector will be 100h.
> 
> If you have BMS = 1, then the reset vector will be FFF0_0100h.
> 
> The default memory window during boot is setup 8MB from
> the end of flash, i.e., starting at FF80_0000h.

Sorry, that should say high-boot (BMS = 1).

For low-boot (BMS = 0), the 8MB window starts at address 0
on CS#0.

In that case the U-Boot reset vector starts in the same sector
as the RCWs, with the RCWs at 0, and the reset vectors at 100h.
Thats why you also see the RCWs in the high-boot image (well,
you used to, not sure if you do now).

Cheers,
Dave