Re: [PATCH] x86: let 32bit use apic_ops too

From: Cyrill Gorcunov
Date: Mon Jul 14 2008 - 14:33:04 EST


[Maciej W. Rozycki - Mon, Jul 14, 2008 at 07:24:15PM +0100]
| On Mon, 14 Jul 2008, Cyrill Gorcunov wrote:
|
| > Maciej, check me please (it's a bit shame but I don't understand the problem
| > that deep) - we have only two errata here 3AP and 11AP. 3AP says - "Writes to
| > error register clears register" so we don't care about locking there since
| > our mostly task is to read error number or clear it (well we're recommened
| > to write before read - but that is different and not related to the hw
| > error).
| >
| > The second problem - 11AP says the following: "Back to back assertions of
| > HOLD or BOFF# may cause lost APIC write cycle". For this case we use LOCK#
| > since - HOLD is not recognized during LOCK cycles (as Intel docs says).
| >
| > Did I miss something? Or maybe it's completely out-of-topic? :)
|
| Check the text of the 11AP erratum -- we simply use one of the Intel's
| recommended workarounds, which says that an APIC read instruction before
| every APIC write instruction will avoid the problem.
|
| Maciej
|

ok, thanks!

- Cyrill -
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