sh: prefetch early exception data on sh4/sh4a.

Prefetch early exception data. There is unused space in our
exception handler cache line anyway, so this is almost free.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 5 insertions, 2 deletions

diff --git a/arch/sh/kernel/cpu/sh3/entry.S b/arch/sh/kernel/cpu/sh3/entry.S
index 0271fe08de27..e984e94394ec 100644
--- a/arch/sh/kernel/cpu/sh3/entry.S
+++ b/arch/sh/kernel/cpu/sh3/entry.S
@@ -463,9 +463,11 @@ tlb_miss:
         sts     pr, k3          ! save original pr value in k3
 
 handle_exception:
+        mova    exception_data, k0
+
         ! Setup stack and save DSP context (k0 contains original r15 on return)
         bsr     prepare_stack_save_dsp
-         nop
+         PREF(k0)
 
         ! Save registers / Switch to bank 0
         mov.l   5f, k2          ! vector register address
@@ -556,10 +558,11 @@ ENTRY(handle_interrupt)
 11:
 #endif /* defined(CONFIG_KGDB) */
         sts     pr, k3          ! save original pr value in k3
+        mova    exception_data, k0
 
         ! Setup stack and save DSP context (k0 contains original r15 on return)
         bsr     prepare_stack_save_dsp
-         nop
+         PREF(k0)
 
         ! Save registers / Switch to bank 0
         bsr     save_regs       ! needs original pr value in k3