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Date: Tue, 11 May 2010 17:03:14 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>,
       "H. Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@elte.hu>,
       Alek Du <alek.du@intel.com>, Arjan van de Ven <arjan@linux.intel.com>,
       Feng Tang <feng.tang@intel.com>, LKML <linux-kernel@vger.kernel.org>,
       Jacob Pan <jacob.jun.pan@intel.com>
Subject: Re: [PATCH 4/8] x86/mrst: change clock selection logic to support
 medfield
Message-ID: <20100511170314.3e9f4d22@lxorguk.ukuu.org.uk>
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On Tue, 11 May 2010 17:50:28 +0200 (CEST)
Thomas Gleixner <tglx@linutronix.de> wrote:

> On Tue, 11 May 2010, Alan Cox wrote:
> 
> > > > +	pr_debug("cpuid result %x\n", regs[CR_EAX]);
> > > > +	pr_info("Moorestown CPU %s identified\n",
> > > > +		(mrst_cpu_chip == MRST_CPU_CHIP_LINCROFT) ?
> > > > +		"Lincroft" : "Penwell");
> > > 
> > >   Are we going to add one of those for each new family ? This is
> > >   really redundant bloat with no value.
> > > 
> > > > +	return mrst_cpu_chip;
> > 
> > From the driver side we need this value determined and visible to the
> > drivers because some things like the IPC interface need to know rather
> > than getting the cpuid magic replicated around.
> 
> Ok. That makes sense. Is there more what MRST drivers need to know ?

At some point they will need to know what platform they are booting on, I
have a possible patch for that which just exposes the boot loader value
but I'm not sure what the final direction on that will be.

For CPU they need to know which CPU type as it affects some bits like the
message formats in use. Probably that means the mrst_cpu_type enum or
function should have an enum value of 0 which means "Not a moorestown
device".