sh: trapped io support V2
The idea is that we want to get rid of the in/out/readb/writeb callbacks from
the machvec and replace that with simple inline read and write operations to
memory. Fast and simple for most hardware devices (think pci).
Some devices require special treatment though - like 16-bit only CF devices -
so we need to have some method to hook in callbacks.
This patch makes it possible to add a per-device trap generating filter. This
way we can get maximum performance of sane hardware - which doesn't need this
filter - and crappy hardware works but gets punished by a performance hit.
V2 changes things around a bit and replaces io access callbacks with a
simple minimum_bus_width value. In the future we can add stride as well.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 8398cf1..f61bf17 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -93,6 +93,9 @@
config ARCH_SUPPORTS_AOUT
def_bool y
+config IO_TRAPPED
+ bool
+
source "init/Kconfig"
menu "System type"