[PATCH 10/10] arm: imx: imx8m: Add basic PSCI provider implementation

[Marek Vasut]

On 1/3/23 00:47, Adam Ford wrote:
> On Mon, Jan 2, 2023 at 5:41 PM Marek Vasut <marex at denx.de> wrote:
>>
>> On 1/2/23 17:44, Adam Ford wrote:
>>> On Wed, Dec 21, 2022 at 9:58 PM Marek Vasut <marex at denx.de> wrote:
>>>>
>>>> On 12/22/22 04:05, Adam Ford wrote:
>>>>> On Wed, Dec 21, 2022 at 6:47 PM Marek Vasut <marex at denx.de> wrote:
>>>>>>
>>>>>> Implement basic PSCI provider to let OS turn CPU cores off and on,
>>>>>> power off and restart the system and determine PSCI version. This
>>>>>> is sufficient to remove the need for the ATF BL31 blob altogether.
>>>>>>
>>>>>> To make use of this functionality, active the following Kconfig options:
>>>>>>      # CONFIG_PSCI_RESET is not set
>>>>>>      CONFIG_ARMV8_MULTIENTRY=y
>>>>>>      CONFIG_ARMV8_SET_SMPEN=y
>>>>>>      CONFIG_ARMV8_SPL_EXCEPTION_VECTORS=y
>>>>>>      CONFIG_ARMV8_EA_EL3_FIRST=y
>>>>>>      CONFIG_ARMV8_PSCI=y
>>>>>>      CONFIG_ARMV8_PSCI_CPUS_PER_CLUSTER=4
>>>>>>      CONFIG_ARMV8_SECURE_BASE=0x970000
>>>>>
>>>>>     I am guessing 0x970000 was for the 8MP based on the previous location
>>>>> of ATF.  Is that true?   If that's the case, can I assume that this
>>>>> address would be  0x910000, 0x920000 and 0x960000 for the imx8mq,
>>>>> imx8mm and imx8mn respectively?
>>>>
>>>> It was for MX8MP, but you can pick whichever address you want, since it
>>>> is U-Boot that installs the SMC handlers, you are no longer forced to
>>>> somehow try and accommodate custom not well fitting load address picked
>>>> by some 3rd party binary blob.
>>>
>>> I patched U-Boot's master with this series and I tried it on
>>> imx8mn_beacon and imx8mm_beacon without success. I never even saw the
>>> SPL message.  I tried to focus on the Nano since the boot ROM in that
>>> one is more similar to that of the 8mp, but the behaviour was similar
>>> to that of the Nano.  Are there any dependencies or should I have used
>>> a specific starting branch?
>>
>> Nope . But if you don't even see output from SPL, that's where I would
>> start looking. Do you see output from SPL without this series ? Note
>> that bulk of this series content applies to U-Boot proper, not SPL so far.
> 
> Without the patch series the generated flash.bin file booted both the
> Mini and the Nano just fine.  I have a pending 8m plus that I can also
> try, since that is what you used.  I just wanted to make sure I was
> starting from the right place before I went too far with it.

Try and drop

[PATCH 09/10] arm: imx: imx8m: Program CSU and TZASC if PSCI provider

does SPL start then ?

I plan to try this on Nano at some point this month too.