On 8/19/2018 11:41 AM, Arnd Bergmann wrote:
Sounds like we need a similar solution for all architectures that
require mmiowb().
That depends on how expensive the barrier is on a given architecture.
It's possible that doing adding the barrier every time is actually
cheaper than keeping track of whether it's needed.
I agree I have no idea about these mentioned architectures and their
barrier types.
If adding mmiowb() is cheaper that could be the way to go as well.
If the barrier is heavy, we definitely want to execute as many
register writes as possible before issuing the barrier.
