sh: math-emu support

This implements initial math-emu support, aimed primarily at SH-3.

Signed-off-by: Takashi YOSHII <takasi-y@ops.dti.ne.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index d1d7244..07d6d69 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -339,6 +339,15 @@
 
 	  This option must be set in order to enable the FPU.
 
+config SH_FPU_EMU
+	bool "FPU emulation support"
+	depends on !SH_FPU && EXPERIMENTAL
+	default n
+	help
+	  Selecting this option will enable support for software FPU emulation.
+	  Most SH-3 users will want to say Y here, whereas most SH-4 users will
+	  want to say N.
+
 config SH_DSP
 	bool "DSP support"
 	depends on !CPU_SH4