Re: [PATCH v2 1/2] ARM: mvebu: Add support to get the ID and the revision of a SoC

[Gregory CLEMENT <gregory.clement-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>]

Hi Andrew,

On 06/01/2014 01:17, Andrew Lunn wrote:
>>>> Does that power down really disable reading from PCIe controller
>>>> registers or is it just PHY power down?
>>>
>>> I haven't experimented with it, but every block that has a clock gate
>>> has a power down, so I doubt it is just a phy power down.
>>
>> Ok, I see. But it isn't documented in the public FS, is it? If there is
>> an extra powerdown register for each ip block, I guess it will also
>> break reading from its registers.
> 
> Hi Sebastian
> 
> The public Kirkwood FS has a memory power management control register,
> Offset 0x20118. It is unclear what it actually does, and if you can
> still access registers when it is off. We would have to poke it and
> see.

Interesting, this registers is mentioned under the section "Core Clock
Power Saving" in the kirkwood datasheet, so maybe we should add this
register to the gating clock

I found similar registers for Armada XP/370, I am going to test what happen
if the PCxy  Memory Power Down are down.


Thanks,

Gregory



> 
> 	Andrew
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-- 
Gregory Clement, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
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