[OLPC-devel] Why ACPI DSDT tables?

[David Zeuthen]

On Mon, 2006-07-10 at 14:10 +0100, David Woodhouse wrote:
> On Sun, 2006-07-09 at 17:30 -0600, Eric W. Biederman wrote:
> > 
> > Skimming the developers list I caught a reference to ACPI DSDT tables.  
> > Unless my memory fails me the DSDT tables require interpretation of AML,
> > and the AML interpreter in the kernel is big (64K+ last time I
> > checked).  With 128MB of RAM it is a cost that can be paid but at
> > the same time I think it is expensive enough that if we can avoid them
> > it gives more memory to other parts of the system.
> > 
> > So what is the reason for wanting an ACPI DSDT? 
> 
> I can't think of any reason why we'd want something like ACPI. We have
> proper hardware documentation -- we don't have to be reduced to that
> kind of abomination.

How do you expect to export things like battery and "on ac power?"
information to userspace? Frankly, the interfaces the Linux kernel
exports for these all suck (/proc/acpi, apm, pmu, etc.) but we work
around that in HAL... and now you want to add *another* interface?

    David