[PATCH] ppc32: workaround for spurious IRQs on PQ2
There is a problem with large amounts of spurious IRQs on PowerPC 82xx
systems.
The problem is corrected by adding sync at the end of cpm2_mask_and_ack.
This may be needed on 8xx as well but has not yet been confirmed.
Signed-off-by: Eugene Surovegin <ebs@ebshome.net>
Signed-off-by: Dan Malek <dan@embeddedalley.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/ppc/syslib/cpm2_pic.c b/arch/ppc/syslib/cpm2_pic.c
index 954b07f..c867be6 100644
--- a/arch/ppc/syslib/cpm2_pic.c
+++ b/arch/ppc/syslib/cpm2_pic.c
@@ -107,6 +107,11 @@
simr = &(cpm2_immr->im_intctl.ic_simrh);
ppc_cached_irq_mask[word] |= 1 << bit;
simr[word] = ppc_cached_irq_mask[word];
+ /*
+ * Work around large numbers of spurious IRQs on PowerPC 82xx
+ * systems.
+ */
+ mb();
}
}