83xx: Marking or Allocating Pages as Cache-Inhibited

[Ben Menchaca]

On Sat, Mar 7, 2009 at 3:51 PM, Benjamin Herrenschmidt <
benh at kernel.crashing.org> wrote:

> On Fri, 2009-03-06 at 10:12 -0600, Ben Menchaca wrote:
> > Testing now...it looks like it (almost) works, though!  Why does
> > setting no-snoop cause snooping to work?  More on the effect on
> > setting that bit in a few minutes...need more testing.
>
> Maybe they got the documentation for that bit backward ? :-)


For posterity...it does appear that this is the case.  I don't have a bus
analyzer to watch the transaction, but a JTAG trigger caught the update
happening if and only if bit 3 was set in the (R|W)DMA descriptor.  My FAE
at FS said he is watching this thread, so hopefully some doc errata can be
generated so others can avoid my confusion :-).

- Ben
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