[PATCH 0/2] Enable private ATF handoff structure

[Michal Simek <michal.simek@xilinx.com>]

On 16. 01. 20 11:05, Marek Vasut wrote:
> On 1/16/20 10:42 AM, Michal Simek wrote:
>> On 16. 01. 20 10:10, Marek Vasut wrote:
>>> On 1/16/20 8:25 AM, Michal Simek wrote:
>>>> čt 19. 12. 2019 v 18:32 odesílatel Michal Simek
>>>> <michal.simek@xilinx.com> napsal:
>>>>>
>>>>> Hi,
>>>>>
>>>>> Xilinx ZynqMP platform is using from the beggining specific structure which
>>>>> is passed from FSBL/SPL to ATF.
>>>>> Maybe in future both options can be supported by ATF and we can remove this
>>>>> private structure completely. But as of now bl31_params are completely
>>>>> ignored by ATF by RESET_TO_BL31=1 build flag.
>>>>>
>>>>> Thanks,
>>>>> Michal
>>>>>
>>>>>
>>>>> Michal Simek (2):
>>>>>   spl: atf: Enable option to rewrite bl2_plat_get_bl31_params()
>>>>>   arm: zynqmp: Wire SPL/ATF handoff structure properly
>>>>>
>>>>>  arch/arm/mach-zynqmp/handoff.c                | 17 +++++++++++-----
>>>>>  arch/arm/mach-zynqmp/include/mach/sys_proto.h |  2 --
>>>>>  arch/arm/mach-zynqmp/spl.c                    |  2 --
>>>>>  common/spl/spl_atf.c                          | 15 +-------------
>>>>>  include/spl.h                                 | 20 +++++++++++++++++++
>>>>>  5 files changed, 33 insertions(+), 23 deletions(-)
>>>>>
>>>>> --
>>>>> 2.24.0
>>>>>
>>>>
>>>> Applied.
>>>
>>> Can't you rather pass DT around ?
>>>
>>
>> Unfortunately not. The best will be just update ATF to support standard
>> method how to get information but that means that we break all backward
>> compatibility and nothing will work.
> 
> Isn't that what Xilinx does with their ABI between all BSP versions ?
> The only stable thing is the ABI version, which never changes :-)

This handoff structure is stable from beginning.


>> Xilinx handoff structure is around fro quite a long time and that's
>> something I need to unfortunately live with.
> 
> Maybe you can develop a better method (DT) in parallel and slowly switch
> over then ?

bl2_plat_get_bl31_params() is something what it is used by ATF for a
long time. Not sure if they are moving to DT way how to describe stuff.
But from my point of view having alternatives and a way for conversion
is right way to go.

Thanks,
Michal