[U-Boot] [PATCH] arm1176: fix relocation

[Darius Augulis]

Hello Heiko,

thanks for reviewing. ok, I will make patch to fix this bug in all arm*/start.S.

Darius.

On Mon, Oct 25, 2010 at 10:11 AM, Heiko Schocher <hs at denx.de> wrote:
> Hello Darius,
>
> Darius Augulis wrote:
>> On 10/24/2010 11:08 PM, Darius Augulis wrote:
>>> Fix relocation code for arm1176, do it like other ARM
>>> CPU's are doing.
>>> Tested only with CONFIG_SKIP_RELOCATE_UBOOT defined
>>> and using nand_spl (booting from nand). Test done on
>>> s3c6410 based board (not yet supported in main line).
>>>
>>> Signed-off-by: Darius Augulis<augulis.darius at gmail.com>
>>> ---
>>>   arch/arm/cpu/arm1176/start.S    |  139 +++++++++++++++++++++++----------------
>>>   arch/arm/cpu/arm1176/u-boot.lds |   15 +++-
>>>   2 files changed, 94 insertions(+), 60 deletions(-)
>>>
>>> diff --git a/arch/arm/cpu/arm1176/start.S b/arch/arm/cpu/arm1176/start.S
>>> index 24e5bf4..0d733f7 100644
>>> --- a/arch/arm/cpu/arm1176/start.S
>>> +++ b/arch/arm/cpu/arm1176/start.S
> [...]
>>> @@ -377,10 +402,9 @@ clbss_l:str     r2, [r0]                /* clear loop...                    */
>>>
>>>   _nand_boot: .word nand_boot
>>>   #else
>>> -    ldr     r0, _TEXT_BASE
>>> -    ldr     r2, _board_init_r
>>> -    sub     r2, r2, r0
>>> -    add     r2, r2, r7      /* position from board_init_r in RAM */
>>> +    ldr     r0, _board_init_r_ofs
>>> +    adr     r1, _start
>>> +    add     r2, r0, r1
>>
>> RFC:
>> I've observed that other ARM CPU's are adding r9 to lr here (add     lr,
>> r0, r9). Even though r9 is not pre-loaded with any value in case
>> CONFIG_SKIP_RELOCATE_UBOOT is defined. Is it bug or not?
>> Maybe it's not tested without CONFIG_SKIP_RELOCATE_UBOOT?
>> I've removed this line because uboot stops booting if it's there.
>> Any comments about it?
>
> Yep, thats a Bug, thanks for detecting this.
>
> But your fix seems to me, is not working for the case if
> CONFIG_SKIP_RELOCATE_UBOOT is !defined, because then you need this
> update of the lr register ... so could you please add this line
> with a "#if !defined(CONFIG_SKIP_RELOCATE_UBOOT)" ... "#endif"
> around it? (And maybe fix all other arm start.S files too?)
>
> bye,
> Heiko
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>