[Qemu-ppc] [RFC PATCH 10/17] PowerPC: booke64: Refactor exception prolog for save/restore regs

[Mihai Caraman]

Refactor exception prolog to allow save/restore register parameters. Add
addition none definition for exception prolog usage.
This is needed for exceptions like Guest Doorbell that use GSRRx regsiters
which do not map on exception type.

Signed-off-by: Mihai Caraman <address@hidden>
---
 arch/powerpc/kernel/exceptions-64e.S |   23 ++++++++---------------
 1 files changed, 8 insertions(+), 15 deletions(-)

diff --git a/arch/powerpc/kernel/exceptions-64e.S 
b/arch/powerpc/kernel/exceptions-64e.S
index 7215cc2..52aa96b 100644
--- a/arch/powerpc/kernel/exceptions-64e.S
+++ b/arch/powerpc/kernel/exceptions-64e.S
@@ -35,7 +35,7 @@
 #define        SPECIAL_EXC_FRAME_SIZE  INT_FRAME_SIZE
 
 /* Exception prolog code for all exceptions */
-#define EXCEPTION_PROLOG(n, type, addition)                                \
+#define EXCEPTION_PROLOG(n, type, srr0, srr1, addition)                        
    \
        mtspr   SPRN_SPRG_##type##_SCRATCH,r13; /* get spare registers */   \
        mfspr   r13,SPRN_SPRG_PACA;     /* get PACA */                      \
        std     r10,PACA_EX##type+EX_R10(r13);                              \
@@ -44,54 +44,47 @@
        addition;                       /* additional code for that exc. */ \
        std     r1,PACA_EX##type+EX_R1(r13); /* save old r1 in the PACA */  \
        stw     r10,PACA_EX##type+EX_CR(r13); /* save old CR in the PACA */ \
-       mfspr   r11,SPRN_##type##_SRR1;/* what are we coming from */        \
+       mfspr   r11,srr1;/* what are we coming from */                      \
        type##_SET_KSTACK;              /* get special stack if necessary */\
        andi.   r10,r11,MSR_PR;         /* save stack pointer */            \
        beq     1f;                     /* branch around if supervisor */   \
        ld      r1,PACAKSAVE(r13);      /* get kernel stack coming from usr */\
 1:     cmpdi   cr1,r1,0;               /* check if SP makes sense */       \
        bge-    cr1,exc_##n##_bad_stack;/* bad stack (TODO: out of line) */ \
-       mfspr   r10,SPRN_##type##_SRR0; /* read SRR0 before touching stack */
+       mfspr   r10,srr0;               /* read SRR0 before touching stack */
 
 /* Exception type-specific macros */
 #define        GEN_SET_KSTACK                                                  
    \
        subi    r1,r1,INT_FRAME_SIZE;   /* alloc frame on kernel stack */
-#define SPRN_GEN_SRR0  SPRN_SRR0
-#define SPRN_GEN_SRR1  SPRN_SRR1
 
 #define CRIT_SET_KSTACK                                                        
    \
        ld      r1,PACA_CRIT_STACK(r13);                                    \
        subi    r1,r1,SPECIAL_EXC_FRAME_SIZE;
-#define SPRN_CRIT_SRR0 SPRN_CSRR0
-#define SPRN_CRIT_SRR1 SPRN_CSRR1
 
 #define DBG_SET_KSTACK                                                     \
        ld      r1,PACA_DBG_STACK(r13);                                     \
        subi    r1,r1,SPECIAL_EXC_FRAME_SIZE;
-#define SPRN_DBG_SRR0  SPRN_DSRR0
-#define SPRN_DBG_SRR1  SPRN_DSRR1
 
 #define MC_SET_KSTACK                                                      \
        ld      r1,PACA_MC_STACK(r13);                                      \
        subi    r1,r1,SPECIAL_EXC_FRAME_SIZE;
-#define SPRN_MC_SRR0   SPRN_MCSRR0
-#define SPRN_MC_SRR1   SPRN_MCSRR1
 
 #define NORMAL_EXCEPTION_PROLOG(n, addition)                               \
-       EXCEPTION_PROLOG(n, GEN, addition##_GEN(n))
+       EXCEPTION_PROLOG(n, GEN, SPRN_SRR0, SPRN_SRR1, addition##_GEN(n))
 
 #define CRIT_EXCEPTION_PROLOG(n, addition)                                 \
-       EXCEPTION_PROLOG(n, CRIT, addition##_CRIT(n))
+       EXCEPTION_PROLOG(n, CRIT, SPRN_CSRR0, SPRN_CSRR1, addition##_CRIT(n))
 
 #define DBG_EXCEPTION_PROLOG(n, addition)                                  \
-       EXCEPTION_PROLOG(n, DBG, addition##_DBG(n))
+       EXCEPTION_PROLOG(n, DBG, SPRN_DSRR0, SPRN_DSRR1, addition##_DBG(n))
 
 #define MC_EXCEPTION_PROLOG(n, addition)                                   \
-       EXCEPTION_PROLOG(n, MC, addition##_MC(n))
+       EXCEPTION_PROLOG(n, MC, SPRN_MCSRR0, SPRN_MCSRR1, addition##_MC(n))
 
 
 /* Variants of the "addition" argument for the prolog
  */
+#define PROLOG_ADDITION_NONE
 #define PROLOG_ADDITION_NONE_GEN(n)
 #define PROLOG_ADDITION_NONE_CRIT(n)
 #define PROLOG_ADDITION_NONE_DBG(n)
-- 
1.7.4.1