powerpc/32: Refactor saving of volatile registers in exception prologs

Exception prologs all do the same at the end:
- Save trapno in stack
- Mark stack with exception marker
- Save r0
- Save r3 to r8

Refactor that into a COMMON_EXCEPTION_PROLOG_END macro.
At the same time use r1 instead of r11.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/e1c45d2e895e0693c42d2a6840df1105a148efea.1615552867.git.christophe.leroy@csgroup.eu

diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index 84e6251622e8be11af7cf7f4e40c07808c3e26cd..ba20bfabdf63b8dd9487da7a899476cedb9392ed 100644 (file)
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -104,15 +104,19 @@
        li      r10, MSR_KERNEL         /* can take exceptions */
        mtmsr   r10                     /* (except for mach check in rtas) */
 #endif
-       stw     r0,GPR0(r11)
+       COMMON_EXCEPTION_PROLOG_END \trapno
+_ASM_NOKPROBE_SYMBOL(\name\()_virt)
+.endm
+
+.macro COMMON_EXCEPTION_PROLOG_END trapno
+       stw     r0,GPR0(r1)
        lis     r10,STACK_FRAME_REGS_MARKER@ha /* exception frame marker */
        addi    r10,r10,STACK_FRAME_REGS_MARKER@l
-       stw     r10,8(r11)
+       stw     r10,8(r1)
        li      r10, \trapno
-       stw     r10,_TRAP(r11)
-       SAVE_4GPRS(3, r11)
-       SAVE_2GPRS(7, r11)
-_ASM_NOKPROBE_SYMBOL(\name\()_virt)
+       stw     r10,_TRAP(r1)
+       SAVE_4GPRS(3, r1)
+       SAVE_2GPRS(7, r1)
 .endm
 
 .macro prepare_transfer_to_handler

diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index 52b40bf529c6d27d9c7ec579ec4f886aa552157b..e1360b88b6cb86e0c9f10ac9c4141248839b4c66 100644 (file)
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -157,14 +157,7 @@ _ENTRY(crit_esr)
        mfspr   r12,SPRN_SRR2
        mfspr   r9,SPRN_SRR3
        rlwinm  r9,r9,0,14,12           /* clear MSR_WE (necessary?)       */
-       stw     r0,GPR0(r11)
-       lis     r10, STACK_FRAME_REGS_MARKER@ha /* exception frame marker */
-       addi    r10, r10, STACK_FRAME_REGS_MARKER@l
-       stw     r10, 8(r11)
-       li      r10, \trapno + 2
-       stw     r10,_TRAP(r11)
-       SAVE_4GPRS(3, r11)
-       SAVE_2GPRS(7, r11)
+       COMMON_EXCEPTION_PROLOG_END \trapno + 2
 _ASM_NOKPROBE_SYMBOL(\name\()_virt)
 .endm
 

diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h
index fa566e89f18bd645d3551394109648fcd2af2b28..4d583fbef0b6f3f2d6a40ee738bff13c546dc60e 100644 (file)
--- a/arch/powerpc/kernel/head_booke.h
+++ b/arch/powerpc/kernel/head_booke.h
@@ -78,14 +78,18 @@ END_BTB_FLUSH_SECTION
        stw     r1, 0(r11);                                                  \
        mr      r1, r11;                                                     \
        rlwinm  r9,r9,0,14,12;          /* clear MSR_WE (necessary?)       */\
-       stw     r0,GPR0(r11);                                                \
-       lis     r10, STACK_FRAME_REGS_MARKER@ha;/* exception frame marker */ \
-       addi    r10, r10, STACK_FRAME_REGS_MARKER@l;                         \
-       stw     r10, 8(r11);                                                 \
-       li      r10, trapno;                                                 \
-       stw     r10,_TRAP(r11);                                              \
-       SAVE_4GPRS(3, r11);                                                  \
-       SAVE_2GPRS(7, r11)
+       COMMON_EXCEPTION_PROLOG_END trapno
+
+.macro COMMON_EXCEPTION_PROLOG_END trapno
+       stw     r0,GPR0(r1)
+       lis     r10, STACK_FRAME_REGS_MARKER@ha /* exception frame marker */
+       addi    r10, r10, STACK_FRAME_REGS_MARKER@l
+       stw     r10, 8(r1)
+       li      r10, \trapno
+       stw     r10,_TRAP(r1)
+       SAVE_4GPRS(3, r1)
+       SAVE_2GPRS(7, r1)
+.endm
 
 .macro prepare_transfer_to_handler
        bl      prepare_transfer_to_handler
@@ -231,11 +235,7 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)
        stw     r1,0(r11);                                                   \
        mr      r1,r11;                                                      \
        rlwinm  r9,r9,0,14,12;          /* clear MSR_WE (necessary?)       */\
-       li      r10, trapno;                                                 \
-       stw     r10,_TRAP(r11);                                              \
-       stw     r0,GPR0(r11);                                                \
-       SAVE_4GPRS(3, r11);                                                  \
-       SAVE_2GPRS(7, r11)
+       COMMON_EXCEPTION_PROLOG_END trapno
 
 #define SAVE_xSRR(xSRR)                        \
        mfspr   r0,SPRN_##xSRR##0;      \