[PATCH 04/14] ARM: shmobile: sh73a0: Remove ->init_machine() special case

Laurent Pinchart laurent.pinchart at ideasonboard.com
Thu Aug 29 20:30:33 EDT 2013


Hi Magnus,

On Wednesday 28 August 2013 21:19:50 Magnus Damm wrote:
> On Wed, Aug 28, 2013 at 9:08 PM, Laurent Pinchart wrote:
> > On Wednesday 28 August 2013 15:40:50 Magnus Damm wrote:
> >> On Fri, Aug 9, 2013 at 7:47 PM, Laurent Pinchart wrote:
> >> > On Friday 09 August 2013 18:48:32 Magnus Damm wrote:
> >> >> From: Magnus Damm <damm at opensource.se>
> >> >> 
> >> >> No need to special case sh73a0 ->init_machine(),
> >> >> so get rid of undesired cpufreq platform device
> >> >> from the generic long term sh73a0 DT support code.
> >> >> 
> >> >> For short term support on KZM9D the DT reference
> >> >> implementation now adds a "cpufreq-cpu0" platform
> >> >> device so that can be used for development.
> >> > 
> >> > Doesn't this go against the spirit of the -reference platforms that
> >> > don't use DT devices in board code ? I don't see an urgent need for
> >> > this, how far along are the DT cpufreq-related bindings ?
> >> 
> >> I'm not sure what the latest state of DT cpufreq bindings are. Actually,
> >> it seems to me that the cpufreq platform device is a software policy that
> >> shouldn't be described with DT. And to be honest, I can't really see how
> >> this policy has anything to do with any particular SoC.
> > 
> > I'm no cpufreq expert, but if we need to register the device in C code,
> > I'm pretty uneasy with having that code in board files. One of the DT
> > goals is to get rid of most board files.
> 
> I'm not sure if we actually _have_to_ register via the platform device, or
> if it just happens to be like that today because no one has bothered
> creating a better abstraction. It is a mystery to me that both a platform
> device is used to select actual driver, and then DT is used to provide
> frequency and voltage information.
> 
> The cpufreq software policy is neither board nor SoC specific. It must be
> application specific. I can understand that putting it in a board file seems
> odd, but putting it in a SoC file is IMO equally odd, and with the added
> damage that people starting to write generic DT code may assume that the SoC
> will keep on using the same cpufreq software policy in the future.
> 
> Perhaps the cpufreq registration interface should be reworked somehow?

Perhaps :-) The situation needs to be at least clarified. Feel free to CC me 
:-)

-- 
Regards,

Laurent Pinchart




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