[POWERPC] 8xx: Move softemu8xx.c from arch/ppc

Previously, Soft_emulate_8xx was called with no implementation, resulting in
build failures whenever building 8xx without math emulation.  The
implementation is copied from arch/ppc to resolve this issue.

However, this sort of minimal emulation is not a very good idea other than
for compatibility with existing userspaces, as it's less efficient than
soft-float and can mislead users into believing they have soft-float.  Thus,
it is made a configurable option, off by default.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

1 files changed, 11 insertions, 0 deletions

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 6f5155d8c324..31804575dd5e 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -198,6 +198,17 @@ config MATH_EMULATION
           unit, which will allow programs that use floating-point
           instructions to run.
 
+config 8XX_MINIMAL_FPEMU
+        bool "Minimal math emulation for 8xx"
+        depends on 8xx && !MATH_EMULATION
+        help
+          Older arch/ppc kernels still emulated a few floating point
+          instructions such as load and store, even when full math
+          emulation is disabled.  Say "Y" here if you want to preserve
+          this behavior.
+
+          It is recommended that you build a soft-float userspace instead.
+
 config IOMMU_VMERGE
         bool "Enable IOMMU virtual merging"
         depends on PPC64