Re: [PATCH] Fixed OMAP3 version check

[Tony Lindgren <tony@atomide.com>]

* Tony Lindgren <tony@atomide.com> [080925 14:47]:
> * Tero.Kristo@nokia.com <Tero.Kristo@nokia.com> [080925 14:45]:
> >  
> > 
> > >-----Original Message-----
> > >From: Balbi Felipe (Nokia-D/Helsinki) 
> > >Sent: 25 September, 2008 14:41
> > >To: ext Tony Lindgren
> > >Cc: Balbi Felipe (Nokia-D/Helsinki); Kristo Tero 
> > >(Nokia-D/Tampere); linux-omap@vger.kernel.org
> > >Subject: Re: [PATCH] Fixed OMAP3 version check
> > >
> > >On Thu, Sep 25, 2008 at 01:31:21PM +0300, Tony Lindgren wrote:
> > >> * Felipe Balbi <felipe.balbi@nokia.com> [080925 13:24]:
> > >> > On Thu, Sep 25, 2008 at 01:17:51PM +0300, Tony Lindgren wrote:
> > >> > > Hi,
> > >> > > 
> > >> > > * Tero Kristo <tero.kristo@nokia.com> [080916 14:59]:
> > >> > > > CPU version was reported incorrectly (e.g. ES3.0 instead of 
> > >> > > > ES2.1.) Also added a piece of optimization for CPU 
> > >type check (omap_type()).
> > >> > > > 
> > >> > > > Signed-off-by: Tero Kristo <tero.kristo@nokia.com>
> > >> > > > ---
> > >> > > >  arch/arm/mach-omap2/id.c |    7 +++++--
> > >> > > >  1 files changed, 5 insertions(+), 2 deletions(-)
> > >> > > > 
> > >> > > > diff --git a/arch/arm/mach-omap2/id.c 
> > >b/arch/arm/mach-omap2/id.c 
> > >> > > > index ab7a6e9..4e2b449 100644
> > >> > > > --- a/arch/arm/mach-omap2/id.c
> > >> > > > +++ b/arch/arm/mach-omap2/id.c
> > >> > > > @@ -37,7 +37,10 @@ EXPORT_SYMBOL(omap_chip_is);
> > >> > > >  
> > >> > > >  int omap_type(void)
> > >> > > >  {
> > >> > > > -	u32 val = 0;
> > >> > > > +	static u32 val;
> > >> > > > +
> > >> > > > +	if (val != 0)
> > >> > > > +		return val;
> > >> > > 
> > >> > > Hmm I guess this would return a random val? :)
> > >> > 
> > >> > it would return 0, look that val is static.
> > >> 
> > >> Ah, sorry I did not see the static. So this is to cache the 
> > >result to 
> > >> optimize it? I'd assume this function is only needed during 
> > >some init 
> > >> code hopefully where performance does not matter..
> > >
> > >Yeah, it's not like we're gonna check the revision after the 
> > >board is botted all up I guess.
> > 
> > PM code will need to either cache the type information or call this
> > check every time when entering off-mode. Some things work differently in
> > secure chips. Could probably just cache this inside PM code.
> 
> How about setting up the save and restore registers properly for GP
> and HS omap once during PM init?

To clarify: Set the save and restore registers and needed functions only
once during PM init depending on the omap type.

Tony