2022-04-21 14:40:30

by Max Filippov

[permalink] [raw]
Subject: [PATCH v2 09/10] xtensa: get rid of stack frame in coprocessor_flush

coprocessor_flush is an ordinary function, it can use all registers.
Don't reserve stack frame for it and use a7 to preserve a0 around the
context saving call.

Signed-off-by: Max Filippov <[email protected]>
---
Changes v1->v2:

- new patch

arch/xtensa/kernel/coprocessor.S | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/arch/xtensa/kernel/coprocessor.S b/arch/xtensa/kernel/coprocessor.S
index af11ddaa8c5f..95412409c49e 100644
--- a/arch/xtensa/kernel/coprocessor.S
+++ b/arch/xtensa/kernel/coprocessor.S
@@ -216,10 +216,8 @@ ENDPROC(fast_coprocessor)

ENTRY(coprocessor_flush)

- /* reserve 4 bytes on stack to save a0 */
- abi_entry(4)
+ abi_entry_default

- s32i a0, a1, 0
movi a4, .Lcp_regs_jump_table
addx8 a4, a3, a4
addx4 a3, a3, a4
@@ -227,10 +225,11 @@ ENTRY(coprocessor_flush)
beqz a4, 1f
l32i a3, a3, CP_REGS_TAB_OFFSET
add a2, a2, a3
+ mov a7, a0
callx0 a4
-1: l32i a0, a1, 0
-
- abi_ret(4)
+ mov a0, a7
+1:
+ abi_ret_default

ENDPROC(coprocessor_flush)

--
2.30.2