powerpc/pseries: Add support for dynamic dma windows

If firmware allows us to map all of a partition's memory for DMA on a particular bridge, create a 1:1 mapping of that memory. Add hooks for dealing with hotplug events. Dynamic DMA windows can use larger than the default page size, and we use the largest one possible. Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
git-mirror · Mar 4, 2011 · 4e8b0cf · 4e8b0cf
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diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
@@ -626,6 +626,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 	disable=	[IPV6]
 			See Documentation/networking/ipv6.txt.
 
+	disable_ddw     [PPC/PSERIES]
+			Disable Dynamic DMA Window support. Use this if
+			to workaround buggy firmware.
+
 	disable_ipv6=	[IPV6]
 			See Documentation/networking/ipv6.txt.