Signed-off-by: Guo Ren <[email protected]> --- arch/csky/kernel/atomic.S | 55 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) create mode 100644 arch/csky/kernel/atomic.S
diff --git a/arch/csky/kernel/atomic.S b/arch/csky/kernel/atomic.S new file mode 100644 index 0000000..e6e9fd2 --- /dev/null +++ b/arch/csky/kernel/atomic.S @@ -0,0 +1,55 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. +#include <linux/linkage.h> +#include <abi/entry.h> + +.text + +/* + * int csky_cmpxchg(int oldval, int newval, int *ptr) + * + * If *ptr != oldval && return 1, + * else *ptr = newval return 0. + */ +ENTRY(csky_cmpxchg) + USPTOKSP + mfcr a3, epc + INCTRAP a3 + + subi sp, 8 + stw a3, (sp, 0) + mfcr a3, epsr + stw a3, (sp, 4) + + psrset ee +1: + ldw a3, (a2) + cmpne a0, a3 + bt16 3f +2: + stw a1, (a2) +3: + mvc a0 + ldw a3, (sp, 0) + mtcr a3, epc + ldw a3, (sp, 4) + mtcr a3, epsr + addi sp, 8 + KSPTOUSP + rte +END(csky_cmpxchg) + +/* + * Called from tlbmodified exception + */ +ENTRY(csky_cmpxchg_fixup) + mfcr a0, epc + lrw a1, 2b + cmpne a1, a0 + bt 1f + subi a1, (2b - 1b) + stw a1, (sp, 0) +1: + rts +END(csky_cmpxchg_fixup) + -- 2.7.4
