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Re: A&M Rattler board question


Todd Smith said:
> I had a similar issue on a custom MPC8250 board. If I remember
> correctly, the number of memory region entries is limited (only 4
> allowed?) with the MMU on that processor.

Correct - the 8250 only supports 4 BAT registers.

>
> --Todd
>
> Richard.von.Lehe@gd-ais.com wrote:
>
>> Has anyone had sucess defining a new memory region using an A&M
>> Rattler board?  I have used the AdderII boards prior to receiving a
>> Rattler, and have not had a problem.
>>
>> My technique for creating a new memory region was to change adder.S
>> and hal_aux.c as follows:
>> (adder.S)
>>        /* NVRAM */
>>        lwi     r3,0xfc000401   # 8-bit, GPCM
>>        lwi     r5,0xffff8f30
>>        stw     r3,BR5(r4)
>>        stw     r5,OR5(r4)
>> (hal_aux.c)
>> CYGARC_MEMDESC_TABLE CYGBLD_ATTRIB_WEAK = {
>>    // Mapping for the Adder 85x development boards
>>    CYGARC_MEMDESC_CACHE(   0xfe000000, 0x00800000 ), // ROM region
>>    CYGARC_MEMDESC_NOCACHE( 0xff000000, 0x00100000 ), // MCP registers
>>    CYGARC_MEMDESC_NOCACHE( 0xfd000000, 0x00008000 ), // Quad UART
>>    CYGARC_MEMDESC_NOCACHE( 0xfc000000, 0x00008000 ), // NVRAM on exp
>> board
>>    CYGARC_MEMDESC_NOCACHE( 0xfa000000, 0x00400000 ), //
>> Control/Status+LEDs
>>    CYGARC_MEMDESC_CACHE(   CYGMEM_REGION_ram, CYGMEM_REGION_ram_SIZE
>> ), // Main memory
>>
>>    CYGARC_MEMDESC_TABLE_END
>>
>>
>> When I make similar changes in rattler.S and hal_aux.c, I end up
>> segfaulting in hal_variant_
>> IRQ_init.
>> (rattler.S)
>>       // CS5 - NVRAM on exp board
>>        lwi     r3,0xFFFF9030
>>        stw     r3,CYGARC_REG_IMM_OR5(r30)
>>        lwi     r3,0xFC000801
>>        stw     r3,CYGARC_REG_IMM_BR5(r30)
>> (hal_aux.c)
>> CYGARC_MEMDESC_TABLE CYGBLD_ATTRIB_WEAK = {
>>    // Mapping for the Rattler board
>>    CYGARC_MEMDESC_CACHE( 0x00000000, 0x01000000 ), // Main memory 60x
>> SDRAM
>>    CYGARC_MEMDESC_CACHE( 0xFE000000, 0x00800000 ), // ROM region
>>    CYGARC_MEMDESC_NOCACHE( 0x80000000, 0x00100000 ), // Extended I/O
>>    CYGARC_MEMDESC_NOCACHE( 0xfc000000, 0x00008000 ), // NVRAM on exp
>> board
>>    CYGARC_MEMDESC_NOCACHE( 0xFF000000, 0x00100000 ), // IMMR registers
>>
>>    CYGARC_MEMDESC_TABLE_END
>>
>>
>> Taking the changes out of hal_aux.c and rattler.S allows my test
>> applications to run (as long as they don't access the memory region in
>> question).  Any ideas or suggestions are welcome.
>> Regards,
>> Rich
>>
>
>
> --
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> and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss
>
>




-- 
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