arm_syscall cacheflush breakage on VIPT platforms

[Bill Gatliff]

Laurent Pinchart wrote:
> Do we really need a cross-architecture solution ? The pressure to implement a 
> working userspace DMA solution seem to come mostly from embedded system 
> developers, and embedded systems usually don't mind arch-specific APIs.
>   

So what if the first attempt is ARM-only?  Let the PPC guys have theirs, 
and so on--- all that experience should give us ideas on how to do the 
One Size Fits All version.  In the meantime, at least we'll have 
something we can use.

It's obviously a tricky problem to solve.  Think of the arch-specific 
version as being "prototype".  We'll be prototyping for a while, I'm 
sure, and the fact that we don't have such an API yet tells me that we 
need a few prototypes to identify how--- if it's even possible--- to 
proceed with a generic implementation.

> In that case developers will all create their own incompatible solutions and 
> the situation will likely get worse.

... and that creates the additional problem of cleaning up the mess 
while at the same time finding and implementing a cross-architecture 
solution.



b.g.

-- 
Bill Gatliff
bgat at billgatliff.com