3 files changed, 46 insertions, 18 deletions

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 3bf72cd2c8fc..7205989b9b59 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -312,6 +312,26 @@ config MATH_EMULATION
           such as fsqrt on cores that do have an FPU but do not implement
           them (such as Freescale BookE).
 
+choice
+        prompt "Math emulation options"
+        default MATH_EMULATION_FULL
+        depends on MATH_EMULATION
+
+config  MATH_EMULATION_FULL
+        bool "Emulate all the floating point instructions"
+        ---help---
+          Select this option will enable the kernel to support to emulate
+          all the floating point instructions. If your SoC doesn't have
+          a FPU, you should select this.
+
+config MATH_EMULATION_HW_UNIMPLEMENTED
+        bool "Just emulate the FPU unimplemented instructions"
+        ---help---
+          Select this if you know there does have a hardware FPU on your
+          SoC, but some floating point instructions are not implemented by that.
+
+endchoice
+
 config PPC_TRANSACTIONAL_MEM
        bool "Transactional Memory support for POWERPC"
        depends on PPC_BOOK3S_64
diff --git a/arch/powerpc/math-emu/Makefile b/arch/powerpc/math-emu/Makefile
index 8d035d2d42a6..1b46ab4f6417 100644
--- a/arch/powerpc/math-emu/Makefile
+++ b/arch/powerpc/math-emu/Makefile
@@ -1,15 +1,15 @@
-
-obj-$(CONFIG_MATH_EMULATION)    += fabs.o fadd.o fadds.o fcmpo.o fcmpu.o \
-                                        fctiw.o fctiwz.o fdiv.o fdivs.o \
-                                        fmadd.o fmadds.o fmsub.o fmsubs.o \
-                                        fmul.o fmuls.o fnabs.o fneg.o \
-                                        fnmadd.o fnmadds.o fnmsub.o fnmsubs.o \
-                                        fres.o fre.o frsp.o fsel.o lfs.o \
-                                        frsqrte.o frsqrtes.o \
-                                        fsqrt.o fsqrts.o fsub.o fsubs.o \
-                                        mcrfs.o mffs.o mtfsb0.o mtfsb1.o \
-                                        mtfsf.o mtfsfi.o stfiwx.o stfs.o \
-                                        math.o fmr.o lfd.o stfd.o
+math-emu-common-objs = math.o fre.o fsqrt.o fsqrts.o frsqrtes.o mtfsf.o mtfsfi.o
+obj-$(CONFIG_MATH_EMULATION_HW_UNIMPLEMENTED) += $(math-emu-common-objs)
+obj-$(CONFIG_MATH_EMULATION_FULL) += $(math-emu-common-objs) fabs.o fadd.o \
+                                        fadds.o fcmpo.o fcmpu.o fctiw.o \
+                                        fctiwz.o fdiv.o fdivs.o  fmadd.o \
+                                        fmadds.o fmsub.o fmsubs.o fmul.o \
+                                        fmuls.o fnabs.o fneg.o fnmadd.o \
+                                        fnmadds.o fnmsub.o fnmsubs.o fres.o \
+                                        frsp.o fsel.o lfs.o frsqrte.o fsub.o \
+                                        fsubs.o  mcrfs.o mffs.o mtfsb0.o \
+                                        mtfsb1.o stfiwx.o stfs.o math.o \
+                                        fmr.o lfd.o stfd.o
 
 obj-$(CONFIG_SPE)               += math_efp.o
 
diff --git a/arch/powerpc/math-emu/math.c b/arch/powerpc/math-emu/math.c
index f9ef34746f16..49eb2ac08fd3 100644
--- a/arch/powerpc/math-emu/math.c
+++ b/arch/powerpc/math-emu/math.c
@@ -13,6 +13,20 @@
 
 #define FLOATFUNC(x)    extern int x(void *, void *, void *, void *)
 
+/* The instructions list which may be not implemented by a hardware FPU */
+FLOATFUNC(fre);
+FLOATFUNC(frsqrtes);
+FLOATFUNC(fsqrt);
+FLOATFUNC(fsqrts);
+FLOATFUNC(mtfsf);
+FLOATFUNC(mtfsfi);
+
+#ifdef CONFIG_MATH_EMULATION_HW_UNIMPLEMENTED
+#undef FLOATFUNC(x)
+#define FLOATFUNC(x)    static inline int x(void *op1, void *op2, void *op3, \
+                                                 void *op4) { }
+#endif
+
 FLOATFUNC(fadd);
 FLOATFUNC(fadds);
 FLOATFUNC(fdiv);
@@ -42,8 +56,6 @@ FLOATFUNC(mcrfs);
 FLOATFUNC(mffs);
 FLOATFUNC(mtfsb0);
 FLOATFUNC(mtfsb1);
-FLOATFUNC(mtfsf);
-FLOATFUNC(mtfsfi);
 
 FLOATFUNC(lfd);
 FLOATFUNC(lfs);
@@ -58,13 +70,9 @@ FLOATFUNC(fnabs);
 FLOATFUNC(fneg);
 
 /* Optional */
-FLOATFUNC(fre);
 FLOATFUNC(fres);
 FLOATFUNC(frsqrte);
-FLOATFUNC(frsqrtes);
 FLOATFUNC(fsel);
-FLOATFUNC(fsqrt);
-FLOATFUNC(fsqrts);
 
 
 #define OP31            0x1f            /*   31 */