From: Guo Ren <guoren@xxxxxxxxxxxxxxxxx> [ 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@xxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- arch/csky/abiv1/inc/abi/entry.h | 19 ++++++++++++++----- arch/csky/abiv2/inc/abi/entry.h | 11 +++++++++++ arch/csky/kernel/atomic.S | 8 ++++++-- 3 files changed, 31 insertions(+), 7 deletions(-) diff --git a/arch/csky/abiv1/inc/abi/entry.h b/arch/csky/abiv1/inc/abi/entry.h index 7ab78bd0f3b13..f35a9f3315ee6 100644 --- a/arch/csky/abiv1/inc/abi/entry.h +++ b/arch/csky/abiv1/inc/abi/entry.h @@ -16,14 +16,16 @@ #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 @@ -45,7 +47,13 @@ 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) @@ -79,9 +87,10 @@ 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) @@ -102,9 +111,9 @@ addi sp, 32 addi sp, 8 - bt 1f + bt 2f KSPTOUSP -1: +2: rte .endm diff --git a/arch/csky/abiv2/inc/abi/entry.h b/arch/csky/abiv2/inc/abi/entry.h index 9897a16b45e5d..94a7a58765dff 100644 --- a/arch/csky/abiv2/inc/abi/entry.h +++ b/arch/csky/abiv2/inc/abi/entry.h @@ -31,7 +31,13 @@ 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) @@ -64,8 +70,10 @@ 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) @@ -86,6 +94,9 @@ addi sp, 40 ldm r16-r30, (sp) addi sp, 72 + bf 1f + mfcr sp, ss0 +1: rte .endm diff --git a/arch/csky/kernel/atomic.S b/arch/csky/kernel/atomic.S index 5b84f11485aeb..3821ef9b75672 100644 --- a/arch/csky/kernel/atomic.S +++ b/arch/csky/kernel/atomic.S @@ -17,10 +17,12 @@ ENTRY(csky_cmpxchg) 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 @@ -47,7 +49,9 @@ ENTRY(csky_cmpxchg) 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) -- 2.20.1
