Re: [PATCH] turn grub-emu into a port

[Vladimir 'phcoder' Serbinenko <phcoder@gmail.com>]

Robert Millan wrote:
> On Sat, Oct 31, 2009 at 12:08:55AM +0100, Vladimir 'phcoder' Serbinenko wrote:
>   
>> Robert Millan wrote:
>>     
>>> This turns grub-emu into a port in order to make it easier to port GRUB to
>>> new CPUs.  A porter can then do the CPU port without having to worry about
>>> firmware and/or hardware drivers initially.
>>>
>>> Patch attached.  Branch is available in
>>> bzr+ssh://bzr.savannah.gnu.org/grub/people/robertmh/grub-emu/
>>>
>>>   
>>>       
>> Following hunk is a regression for me:
>> -  return (tv.tv_sec * GRUB_TICKS_PER_SECOND
>> -         + (((tv.tv_sec % GRUB_TICKS_PER_SECOND) * 1000000 + tv.tv_usec)
>> -            * GRUB_TICKS_PER_SECOND / 1000000));
>> +  GRUB_COMPILE_TIME_ASSERT (GRUB_TICKS_PER_SECOND == 1000000);
>> +  return (tv.tv_sec * 1000000 + tv.tv_usec);
>> Having virtual clock going at any rate is an advantage for debugging.
>>     
>
> I don't get what you mean.  When GRUB runs on a Unix system, a tick
> represents a 1000000th fraction of a second, and therefore
> GRUB_TICKS_PER_SECOND is 1000000.
>
> The old behaviour tried to emulate the behaviour of the specific hardware
> platform, but with grub-emu being a standalone port this doesn't make sense.
>
> I don't think we can have both things (old tick behaviour + portable grub-emu).
> Was that behaviour useful?  It seems to me that GRUB routines don't directly
> care about number of ticker per second, but rather just use it as a means to
> archieve something else.  E.g. to compare output of grub_get_rtc().
>
>   
I meant: keep GRUB_TICKS_PER_SECOND=1000000 per default but allow easy
adjustment to any number by coder

-- 
Regards
Vladimir 'phcoder' Serbinenko
Personal git repository: http://repo.or.cz/w/grub2/phcoder.git