linux/arch/csky/kernel/atomic.S
Guo Ren b0ae5e26b8 csky: Remove prologue of page fault handler in entry.S
There is a prologue on page fault handler which marking pages dirty
and/or accessed in page attributes, but all of these have been
handled in handle_pte_fault.

 - Add flush_tlb_one in vmalloc page fault instead of prologue.
 - Using cmxchg_fixup C codes in do_page_fault instead of ASM one.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2021-01-12 09:52:40 +08:00

62 lines
894 B
ArmAsm

/* 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
RD_MEH a3
WR_MEH a3
mfcr a3, epc
addi a3, TRAP0_SIZE
subi sp, 16
stw a3, (sp, 0)
mfcr a3, epsr
stw a3, (sp, 4)
mfcr a3, usp
stw a3, (sp, 8)
psrset ee
#ifdef CONFIG_CPU_HAS_LDSTEX
1:
ldex a3, (a2)
cmpne a0, a3
bt16 2f
mov a3, a1
stex a3, (a2)
bez a3, 1b
2:
sync.is
#else
GLOBAL(csky_cmpxchg_ldw)
ldw a3, (a2)
cmpne a0, a3
bt16 3f
GLOBAL(csky_cmpxchg_stw)
stw a1, (a2)
3:
#endif
mvc a0
ldw a3, (sp, 0)
mtcr a3, epc
ldw a3, (sp, 4)
mtcr a3, epsr
ldw a3, (sp, 8)
mtcr a3, usp
addi sp, 16
KSPTOUSP
rte
END(csky_cmpxchg)