Messages in this thread | | | Subject | Re: MMIO and gcc re-ordering issue | From | Benjamin Herrenschmidt <> | Date | Fri, 30 May 2008 17:24:27 +1000 |
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On Fri, 2008-05-30 at 08:07 +0200, Haavard Skinnemoen wrote: > On Fri, 30 May 2008 11:13:23 +1000 > Benjamin Herrenschmidt <benh@kernel.crashing.org> wrote: > > > > Currently, this is the only interface I know that can do native-endian > > > accesses, so if you take it away, I'm gonna need an alternative > > > interface that doesn't do byteswapping. > > > > Are you aware that these also don't provide any ordering guarantee ? > > Yes, but I am not aware of any alternative. > > I think the drivers I've written have the necessary barriers (or dma > ops with implicit barriers) that they don't actually depend on any > DMA vs. MMIO ordering guarantees. I hope MMIO vs. MMIO ordering is > guaranteed though?
Only to the same address I'd say.
Ben.
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