[POWERPC] Add cpu feature for SPE handling

Make it so that SPE support can be determined at runtime.  This is similiar
to how we handle AltiVec.  This allows us to have SPE support built in and
work on processors with and without SPE.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

1 files changed, 11 insertions, 4 deletions

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index e477c9d0498b..57c589c34147 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -669,9 +669,13 @@ int set_fpexc_mode(struct task_struct *tsk, unsigned int val)
          * mode (asyn, precise, disabled) for 'Classic' FP. */
         if (val & PR_FP_EXC_SW_ENABLE) {
 #ifdef CONFIG_SPE
-                tsk->thread.fpexc_mode = val &
-                        (PR_FP_EXC_SW_ENABLE | PR_FP_ALL_EXCEPT);
-                return 0;
+                if (cpu_has_feature(CPU_FTR_SPE)) {
+                        tsk->thread.fpexc_mode = val &
+                                (PR_FP_EXC_SW_ENABLE | PR_FP_ALL_EXCEPT);
+                        return 0;
+                } else {
+                        return -EINVAL;
+                }
 #else
                 return -EINVAL;
 #endif
@@ -697,7 +701,10 @@ int get_fpexc_mode(struct task_struct *tsk, unsigned long adr)
 
         if (tsk->thread.fpexc_mode & PR_FP_EXC_SW_ENABLE)
 #ifdef CONFIG_SPE
-                val = tsk->thread.fpexc_mode;
+                if (cpu_has_feature(CPU_FTR_SPE))
+                        val = tsk->thread.fpexc_mode;
+                else
+                        return -EINVAL;
 #else
                 return -EINVAL;
 #endif