[U-Boot-Users] cfi_flash.c and lost volatile qualifier

Joakim Tjernlund joakim.tjernlund at transmode.se
Wed Apr 30 18:11:38 CEST 2008


On Wed, 2008-04-30 at 11:02 -0500, Scott Wood wrote:
> On Wed, Apr 30, 2008 at 05:34:56PM +0200, Joakim Tjernlund wrote:
> > 
> > On Wed, 2008-04-30 at 10:21 -0500, Scott Wood wrote:
> > > On Wed, Apr 30, 2008 at 05:11:09PM +0200, Joakim Tjernlund wrote:
> > > > Yet the in_bex()/out_bex() functions in PowerPC linux uses sync and all
> > > > SOC drivers are encouraged to use them. What a waste :(
> > > 
> > > sync is needed in some of the cases, to sync I/O accesses with DMA buffer
> > > accesses.  Ideally, we could trust the driver writers to put
> > > synchronization in where needed, but it seems Linux has too much x86
> > > heritage for that.
> > 
> > Perhaps, is sync needed in this case for non-smp too? or is eieio
> > enough?
> 
> Yes, sync is needed -- eieio doesn't order between stores to cacheable
> memory and stores to cache-inhibited memory.

OK, thanks

> 
> > Anyway, just have a look at ucc_geth 
> 
> Do I have to? :-)

Yes, it needs a little love here and there :)
Especially Timur, his little "rename the tx/rx clock" trick
costed me a few days :)

 Jocke




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