[ Upstream commit
f8e17c17b81070f38062dce79ca7f4541851dadd ]
In the past, we didn't care about kernel sp when saving pt_reg. But in some
cases, we still need pt_reg->usp to represent the kernel stack before enter
exception.
For cmpxhg in atomic.S, we need save and restore usp for above.
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
#define LSAVE_A4 40
#define LSAVE_A5 44
+#define usp ss1
+
.macro USPTOKSP
- mtcr sp, ss1
+ mtcr sp, usp
mfcr sp, ss0
.endm
.macro KSPTOUSP
mtcr sp, ss0
- mfcr sp, ss1
+ mfcr sp, usp
.endm
.macro SAVE_ALL epc_inc
add lr, r13
stw lr, (sp, 8)
+ mov lr, sp
+ addi lr, 32
+ addi lr, 32
+ addi lr, 16
+ bt 2f
mfcr lr, ss1
+2:
stw lr, (sp, 16)
stw a0, (sp, 20)
ldw a0, (sp, 12)
mtcr a0, epsr
btsti a0, 31
+ bt 1f
ldw a0, (sp, 16)
mtcr a0, ss1
-
+1:
ldw a0, (sp, 24)
ldw a1, (sp, 28)
ldw a2, (sp, 32)
addi sp, 32
addi sp, 8
- bt 1f
+ bt 2f
KSPTOUSP
-1:
+2:
rte
.endm
mfcr lr, epsr
stw lr, (sp, 12)
+ btsti lr, 31
+ bf 1f
+ addi lr, sp, 152
+ br 2f
+1:
mfcr lr, usp
+2:
stw lr, (sp, 16)
stw a0, (sp, 20)
mtcr a0, epc
ldw a0, (sp, 12)
mtcr a0, epsr
+ btsti a0, 31
ldw a0, (sp, 16)
mtcr a0, usp
+ mtcr a0, ss0
#ifdef CONFIG_CPU_HAS_HILO
ldw a0, (sp, 140)
addi sp, 40
ldm r16-r30, (sp)
addi sp, 72
+ bf 1f
+ mfcr sp, ss0
+1:
rte
.endm
mfcr a3, epc
addi a3, TRAP0_SIZE
- subi sp, 8
+ 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
mtcr a3, epc
ldw a3, (sp, 4)
mtcr a3, epsr
- addi sp, 8
+ ldw a3, (sp, 8)
+ mtcr a3, usp
+ addi sp, 16
KSPTOUSP
rte
END(csky_cmpxchg)