[OpenBIOS] [SOLVED] [WIP] ppc: Set up r2, respect function descriptors on ppc64

[Andreas Färber]

Am 23.11.2010 um 20:52 schrieb Blue Swirl:

> On Tue, Nov 23, 2010 at 8:00 AM, Andreas Färber <andreas.faerber at web.de 
> > wrote:
>> Ugly but functional!
>> ---
>>  arch/ppc/qemu/start.S    |   24 ++++++++++++++++++++++++
>>  arch/ppc64/qemu/ldscript |   10 ++++++++++
>>  2 files changed, 34 insertions(+), 0 deletions(-)
>>
>> diff --git a/arch/ppc/qemu/start.S b/arch/ppc/qemu/start.S
>> index eef4293..a3b727d 100644
>> --- a/arch/ppc/qemu/start.S
>> +++ b/arch/ppc/qemu/start.S
>> @@ -272,12 +272,18 @@ GLOBL(__vectors):
>>
>>  call_dsi_exception:
>>        LOAD_REG_IMMEDIATE(r3, dsi_exception)
>> +#ifdef __powerpc64__
>> +       ld r3, 0(r3)
>> +#endif
>
> How about LOAD_REG_FUNC macro, which automatically performs the load?

Yeah, working on it, I had LOAD_REG_ADDR() in an earlier FYI patch.  
Depending on whether the dotted name is globally visible we could just  
load that instead and spare us the ld.

>> @@ -289,7 +295,11 @@ exception_return:
>>  __divide_error:
>>  trap_error:
>>        mflr    r3
>> +#ifdef __powerpc64__
>> +       b       .unexpected_excep
>> +#else
>>        b       unexpected_excep
>> +#endif
>
> This #ifdeffery could be avoided with a macro to add the dot for  
> ppc64:
>        b       BRANCH_LABEL(unexpected_excep)

Right. Alex suggested the same. I like your macro name.
During local testing I do find my #ifdef'ery more convenient for going  
back and forth.

Andreas