[U-Boot-Users] Problems with the port to PPC 405EP ev. board

[U-Boot-Users] Problems with the port to PPC 405EP ev. board

[llandre]

I'm porting U-Boot to this board.
I compared the boot code (start.S) with the OpenBios' startup (entry.S). 
Openbios, in case PLL is not initialized, writes default values into the 
PLLMR0 and PLLMR1 registers. U-Boot, in my understanding, assumes PLL is 
already initialized and read its registers in order to determine the 
frequencies and other information (get_sys_info in file speed.c). Is it 
correct? If yes, why does not it initialize the PLL?
I tried to add some code to start.S in order to do the same thing openbios 
does, but the assembler does not like it:

---------------------------------------------------------------------------
ppc-linux-gcc -Wa,-gstabs -D__ASSEMBLY__ -g  -Os  -mrelocatable -ffixed-r14 
-meabi -mrelocatable -ffixed-r14 -meabi -D__KERNEL__ -DTEXT_BASE=0xFFF80000 
-I/proj/ppc405ep/sw/u-boot/include -fno-builtin -pipe -DCONFIG_PPC 
-D__powerpc__ -DCONFIG_4xx -ffixed-r2 -ffixed-r29 -mstring -Wa,-m405 
-mcpu=405 -msoft-float -DCONFIG_PPC -D__powerpc__ -DCONFIG_4xx -ffixed-r2 
-ffixed-r29 -mstring -Wa,-m405 -mcpu=405 -msoft-float -c -o start.o 
/proj/ppc405ep/sw/u-boot/cpu/ppc4xx/start.S
/proj/ppc405ep/sw/u-boot/cpu/ppc4xx/start.S: Assembler messages:
/proj/ppc405ep/sw/u-boot/cpu/ppc4xx/start.S:849: Error: attempt to 
.org/.space backwards? (-8)
/proj/ppc405ep/sw/u-boot/cpu/ppc4xx/start.S:1582: Internal error!
Assertion failure in write_contents at ../../gas/write.c line 1187.
Please report this bug.
make[1]: *** [start.o] Error 1
make[1]: Leaving directory `/proj/ppc405ep/sw/u-boot/cpu/ppc4xx'
make: *** [subdirs] Error 1
---------------------------------------------------------------------------

I never saw an error like that. Anybody can tell me what is wrong?

Thanx in advance.



llandre

[U-Boot-Users] Problems with the port to PPC 405EP ev. board

[Vladimir Gurevich]

Hello,

I'd guess that attaching your new start.S or, at least,
the diff to the original one will definitely help...

Best regards,
Vladimir

llandre wrote:
> ppc-linux-gcc -Wa,-gstabs -D__ASSEMBLY__ -g  -Os  -mrelocatable 
> -ffixed-r14 -meabi -mrelocatable -ffixed-r14 -meabi -D__KERNEL__ 
> -DTEXT_BASE=0xFFF80000 -I/proj/ppc405ep/sw/u-boot/include -fno-builtin 
> -pipe -DCONFIG_PPC -D__powerpc__ -DCONFIG_4xx -ffixed-r2 -ffixed-r29 
> -mstring -Wa,-m405 -mcpu=405 -msoft-float -DCONFIG_PPC -D__powerpc__ 
> -DCONFIG_4xx -ffixed-r2 -ffixed-r29 -mstring -Wa,-m405 -mcpu=405 
> -msoft-float -c -o start.o /proj/ppc405ep/sw/u-boot/cpu/ppc4xx/start.S
> /proj/ppc405ep/sw/u-boot/cpu/ppc4xx/start.S: Assembler messages:
> /proj/ppc405ep/sw/u-boot/cpu/ppc4xx/start.S:849: Error: attempt to 
> .org/.space backwards? (-8)
> /proj/ppc405ep/sw/u-boot/cpu/ppc4xx/start.S:1582: Internal error!
> Assertion failure in write_contents at ../../gas/write.c line 1187.
> Please report this bug.
> make[1]: *** [start.o] Error 1
> make[1]: Leaving directory `/proj/ppc405ep/sw/u-boot/cpu/ppc4xx'
> make: *** [subdirs] Error 1
> ---------------------------------------------------------------------------
> 
> I never saw an error like that. Anybody can tell me what is wrong?

[U-Boot-Users] Problems with the port to PPC 405EP ev. board

[Vladimir Gurevich]

Hello,

My suggestion will be to move your pll_write and reset_cpu 
functions to the bottom of the file, at least past the exception
vectors. Remember, that the execution starts at 0x100 
and there are only 256 bytes before the next exception 
vector. Your problem is that your code is too big to
be placed in the exception vector space and thus overlapped with
the next vector.

Hope, this helps.
Vladimir

llandre wrote:
> 
>> Hello,
>>
>> I'd guess that attaching your new start.S or, at least,
>> the diff to the original one will definitely help...
> 
> 
> Sorry, I thought we were not allowed to send attachments to the mailing 
> list.
> I attached the new start.S. The new code is enclosed by the "#if 
> (defined(CONFIG_BUBINGA405EP) && defined(CONFIG_NO_SERIAL_EEPROM))" 
> directives.
> 
> 
> 
> llandre

[U-Boot-Users] Problems with the port to PPC 405EP ev. board

[llandre]

>My suggestion will be to move your pll_write and reset_cpu functions to 
>the bottom of the file, at least past the exception
>vectors. Remember, that the execution starts at 0x100 and there are only 
>256 bytes before the next exception vector. Your problem is that your code 
>is too big to
>be placed in the exception vector space and thus overlapped with
>the next vector.

You were right. I moved the new code at the end of the file and now the 
build is ok.
Many thanks again and best regards.


llandre