[U-Boot] ARM: Incorrect ROM protection range?

[Po-Yu Chuang]

Dear Albert,

On Tue, Mar 1, 2011 at 8:22 PM, Albert ARIBAUD <albert.aribaud at free.fr> wrote:
> Le 01/03/2011 09:31, Po-Yu Chuang a écrit :
>> On Fri, Feb 25, 2011 at 4:00 PM, Po-Yu Chuang<ratbert.chuang at gmail.com>
>>  wrote:
>>
>> I tried the following command and it seems work:
>>
>> for f in `find * -type f`; do sed -i 's/\<_end\>/__bss_end/g' $f; done
>>
>>
>> but when I tried to build, I got some error in standalone example:
>>
>>
[snip]
>> libstubs.o: In function `app_startup':
>> /home/ratbert/linux/u-boot/examples/standalone/stubs.c:206: undefined
>> reference to `__bss_end'
>> make[1]: *** [hello_world] Error 1
>> make[1]: Leaving directory
>> `/home/ratbert/linux/u-boot/examples/standalone'
>> make: *** [examples/standalone] Error 2
>>
>>
>> It looks like that _end as end of BSS section is a convention to GNU
>> toolchain.
>> Should I simply fix it by hand, or should we reconsider the whole naming
>> thing?
>
> Indeed, since the link command line does not mention a linker file, then the
> default toolchain linker file was invoked. You can see the linker script
> using ld --verbose (be sure to use the toolchain's ld, not your host's).
> Mine (ELDK4.2 and CodeSourcery 2010q1) define __bss_start and __bss_start__
> before the BSS section, and _bss_end__ and __bss_end__ after it, then
> __end__ and _end after that. No surprise that __bss_end did not work.
>
> But examples (ang more generally, standalone applications) are not supposed
> to use symbols from U-Boot linker files; so there is no reason to replace
> __bss_end in these.
>
> Still, we *could* align on the ELDK/CS linkers' output and use _bss_end__
> and/or __bss_end__ rather than __bss_end for U-Boot, unless some other
> toolchain has radically different default linker scripts. Comments anyone?

I prefer the __bss_end__ solution. Not only because it doesn't require manual
fixes after sed replacement command, but it also makes the semantics of
app_startup() of the standalone example program clearer.
If there is no other comment, I will submit patches using __bss_end__ later.

best regards,
Po-Yu Chuang