ARC: optimize kernel bss clearing in early boot code

using ARC ZOL which reduces tot num of instructions by half

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

1 files changed, 4 insertions, 3 deletions

diff --git a/arch/arc/kernel/head.S b/arch/arc/kernel/head.S
index 07a58f2d3077..4d2481bd8b98 100644
--- a/arch/arc/kernel/head.S
+++ b/arch/arc/kernel/head.S
@@ -77,10 +77,11 @@ stext:
         ; Clear BSS before updating any globals
         ; XXX: use ZOL here
         mov     r5, __bss_start
-        mov     r6, __bss_stop
+        sub     r6, __bss_stop, r5
+        lsr.f   lp_count, r6, 2
+        lpnz    1f
+        st.ab   0, [r5, 4]
 1:
-        st.ab   0, [r5,4]
-        brlt    r5, r6, 1b
 
         ; Uboot - kernel ABI
         ;    r0 = [0] No uboot interaction, [1] cmdline in r2, [2] DTB in r2