some question about writel implement in arm platform

[Arnd Bergmann]

On Thursday 16 April 2015 13:28:41 yoma sophian wrote:
> hi all:
> the implementation of writel in ARM is writel_relaxed() with barrier
> before (DSB + outer cache sync).
> 
> if the memory is device memory, shall we still need outer cache sync?

Yes.

> if the memory is normal normal, under what circumstance we will write
> it with writel.

For normal memory, you never use writel.

> As far as I know, the writel is used for register writing.

Correct.

	Arnd