Ar Sul, 2006-09-10 am 08:36 +1000, ysgrifennodd Benjamin Herrenschmidt: > Well, some of you (Alan, you, etc...) seem to imply that it's always > been the rule to have a memory store followed by an MMIO write be > strongly ordered.
It has always been the rule > However, if you look at drivers like e1000, USB OHCI, or even sungem > (:-) they, all have at least wmb()'s between updating descriptor in Driver hacks to cope with platform authors who got read/writel wrong. > semantics. At least what is implemented currently on PowerPC is the > __raw_* versions which not only have no barriers at all (they don't even > order between MMIOs, for example, readl might cross writel), and do no > endian swap. Quite a mess of semantics if you ask me... Then there has __writel/__readl seems more in keeping for just not locking. - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
