diff options
| author | Vineet Gupta <vgupta@synopsys.com> | 2014-04-17 17:13:26 +0530 |
|---|---|---|
| committer | Vineet Gupta <vgupta@synopsys.com> | 2014-06-26 10:14:05 +0530 |
| commit | bef444a33004f4062930df1fc703a25dd6d7b460 (patch) | |
| tree | ed7f20642c6319ca0d8c1841d97ad10fa1ba2f01 | |
| parent | ba25915fb2cd18152cb14b144dbe8bf2f2bd8e45 (diff) | |
| download | linux-bef444a33004f4062930df1fc703a25dd6d7b460.tar.gz | |
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>
| -rw-r--r-- | arch/arc/kernel/head.S | 7 | ||||
| -rw-r--r-- | arch/arc/kernel/vmlinux.lds.S | 2 |
2 files changed, 5 insertions, 4 deletions
diff --git a/arch/arc/kernel/head.S b/arch/arc/kernel/head.S index 07a58f2d307772..4d2481bd8b98dc 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 diff --git a/arch/arc/kernel/vmlinux.lds.S b/arch/arc/kernel/vmlinux.lds.S index 2555f5886af624..dd35bde39f6938 100644 --- a/arch/arc/kernel/vmlinux.lds.S +++ b/arch/arc/kernel/vmlinux.lds.S @@ -116,7 +116,7 @@ SECTIONS _edata = .; - BSS_SECTION(0, 0, 0) + BSS_SECTION(4, 4, 4) #ifdef CONFIG_ARC_DW2_UNWIND . = ALIGN(PAGE_SIZE); |