newbus bus access routines and bus_space_barrier()
adrian at freebsd.org
Sun Oct 16 16:20:48 UTC 2011
On 16 October 2011 11:45, Warner Losh <imp at bsdimp.com> wrote:
> Usually they are needed, but we get away without them often because they are needed in a limited set of circumstances and we have memory barriers in our locking primitives.
Hm, so should this actively be fixed for drivers? I note iwn(4) does
its own (correct looking?) barrier stuff. A few other drivers do. ath
wi(4) doesn't yet do barriers, but someone supplied a patch that may
work better on ppc if said barriers are included.
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