Re: [PATCH] powerpc xmon: drop the option `i` in cacheflush

[Balamuruhan S <bala24@linux.ibm.com>]

On Tue, 2020-03-24 at 14:52 +1100, Michael Ellerman wrote:
> "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> writes:
> > Segher Boessenkool wrote:
> > > On Mon, Mar 23, 2020 at 04:55:48PM +0530, Balamuruhan S wrote:
> > > > Data Cache Block Invalidate (dcbi) instruction implemented in 32-bit
> > > > designs prior to PowerPC architecture version 2.01 and got obsolete
> > > > from version 2.01.
> 
> We still support 32-bit ...

Okay, got it.

> 
> > > It was added back in 2.03.  It also exists in 64-bit designs (using
> > > category embedded), in 2.07 still even.
> > 
> > Indeed, it has been part of Book3e.
> > 
> > It isn't clear if this is still useful in this context (xmon) though, 
> > since 'dcbf' seems to be equivalent in most respects. At the very least, 
> > we should restrict this to Book3e, if it is of value there.
> 
> Looking at the ISA it looks like dcbf is more or less equivalent and we
> could probably drop the explicit invalidate command.
> 
> But the simplest option is probably to just ifdef it out for
> PPC_BOOK3S_64.

Sure, I will make the changes as suggested.

Thank you!

-- Bala
> 
> cheers