From mboxrd@z Thu Jan  1 00:00:00 1970
From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Subject: Re: cpufreq implementation for OMAP under xen
	hypervisor.
Date: Fri, 26 Sep 2014 14:13:27 -0400
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To: Oleksandr Dmytryshyn <oleksandr.dmytryshyn@globallogic.com>
Cc: Ian Campbell <Ian.Campbell@citrix.com>, Stefano Stabellini <stefano.stabellini@eu.citrix.com>, jinsong.liu@alibaba-inc.com, Tim Deegan <tim@xen.org>, xen-devel <xen-devel@lists.xen.org>, Jan Beulich <jbeulich@suse.com>, jacob.shin@amd.com, Andrii Tseglytskyi <andrii.tseglytskyi@globallogic.com>
List-Id: xen-devel@lists.xenproject.org

> > The architecture looks sane to me. As Konrad pointed out, the difficulty
> > here is to be able to upstream the changes to the Linux driver in 2),
> > that you later in the thread identified as
> > drivers/cpufreq/cpufreq-cpu0.c.
> I'll write driver drivers/xen/xen-cpufreq.c and it replace original
> drivers/cpufreq/cpufreq.c
> And in the original cpufreq-cpu0 driver I'll chande only one string -
> path in the device tree
> with the settings for the CPUs opp:
> string
> np = of_find_node_by_path("/cpus/cpu@0");
> will changed to:
> np = of_find_node_by_path("/cpus/cpu@0/private_data/cpu@0");
> 
> > If the changes are not invasive and you manage to upstream them in
> > Linux, I am all for this solution.
> In Linux kernel I should make few changes:
> 1. Enable CONFIG_CPU_FREQ_TABLE
> with disabled CONFIG_CPU_FREQ
> 2. Enable CONFIG_GENERIC_CPUFREQ_CPU0
> with disabled CONFIG_CPU_FREQ
> 
> I mean make those configs dependent on
> CONFIG_CPU_FREQ or CONFIX_XEN_DOM0
> instead of
> CONFIG_CPU_FREQ

Gosh no. Please make it work runtime.
> 
> Oleksandr Dmytryshyn | Product Engineering and Development
> GlobalLogic
> M +38.067.382.2525
> www.globallogic.com
> 
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