[U-Boot] [PATCHv2 2/3] ARMv8/layerscape: Add FSL PPA support

[york sun]

On 01/22/2016 12:14 PM, Bhupesh Sharma wrote:
> 
> 
>> -----Original Message-----
>> From: Scott Wood [mailto:oss at buserror.net]
>> Sent: Saturday, January 23, 2016 1:39 AM
>> To: york sun; Zhiqiang Hou; u-boot at lists.denx.de;
>> albert.u.boot at aribaud.net; Mingkai.hu at freescale.com; Stuart Yoder;
>> leoli at freescale.com; prabhakar at freescale.com;
>> bhupesh.sharma at freescale.com; Zhiqiang Hou
>> Subject: Re: [PATCHv2 2/3] ARMv8/layerscape: Add FSL PPA support
>>
>> On Fri, 2016-01-22 at 20:05 +0000, york sun wrote:
>>> On 01/21/2016 01:53 AM, Zhiqiang Hou wrote:
>>>> From: Hou Zhiqiang <Zhiqiang.Hou at freescale.com>
>>>>
>>>> The FSL Primary Protected Application (PPA) is a software component
>>>> loaded during boot which runs in TrustZone and remains resident
>>>> after boot.
>>>>
>>>> Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou at freescale.com>
>>>> ---
>>>> Tested on LS1043A RDB board
>>>>
>>>
>>> I presume PSCI is implemented in PPA. How does the SMP boot flow
>>> change with PPA? U-boot has to remain functional in the absence of PPA,
>> right?
>>>
>>> Would it be possible to write a readme for PPA?
>>
>> Also, how does the devicetree get updated to indicate the presence of
>> PSCI?
>>
> 
> One needs to add PSCI node in the DTS for the same, claiming support for PSCI specification.
> The cpu.enable_method needs to be changed from spin-table to psci as well.
> 
> See http://lxr.free-electrons.com/source/Documentation/devicetree/bindings/arm/psci.txt for details.
> 

Bhupesh,

Before PPA is fully adopted, u-boot has to detect the existence of PPA and
decide to use PSCI or spin table, right? So the device tree node should also be
fixed accordingly.

York