[PATCH 0/7] riscv: Correctly handle IPIs already pending upon boot

[Sean Anderson]

On 9/8/20 10:38 PM, Sean Anderson wrote:
> On 9/8/20 10:02 PM, Rick Chen wrote:
>> Hi Sean
>>
>>> On the K210, the prior stage bootloader does not clear IPIs. This presents
>>> a problem, because U-Boot up until this point assumes (with one exception)
>>> that IPIs are cleared when it starts. This series attempts to fix this in a
>>> robust manner, and fix several concurrency bugs I noticed while fixing
>>> these other areas. Heinrich previously submitted a patch addressing part of
>>> this problem in [1].
>>>
>>> [1] https://patchwork.ozlabs.org/project/uboot/patch/20200811035648.3284-1-xypron.glpk@gmx.de/
>>>
>>
>> It sounds like that the bootloader does not deal with SMP flow well
>> and jump to u-boot-spl, right ?
>>
>> I have a question that why not try to fix the prior stage bootloader
>> to clear IPIs correctly?
> 
> Because it is a ROM :)

Err, perhaps I should clarify. When I say "prior stage bootloader," I
mean that in the general sense of "anything which comes before U-Boot,"
and not to refer specifically to SPL or TPL. For the k210, this is
something akin to the ZSBL on an fu540.

--Sean