[Blackfin] arch: change the trace buffer control start/stop logic in the exception handlers
To save/restore the trace buffer control so that if we take an exception
after turning off the trace buffer at a higher level we dont inadvertently
turn the trace buffer back on
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
diff --git a/arch/blackfin/mach-common/entry.S b/arch/blackfin/mach-common/entry.S
index fdd9bf43..2cbb7a0 100644
--- a/arch/blackfin/mach-common/entry.S
+++ b/arch/blackfin/mach-common/entry.S
@@ -121,6 +121,7 @@
(R7:6,P5:4) = [sp++];
ASTAT = [sp++];
SAVE_ALL_SYS
+ DEBUG_HWTRACE_SAVE(p5, r7)
#ifdef CONFIG_MPU
R0 = SEQSTAT;
R1 = SP;
@@ -132,14 +133,13 @@
#else
call __cplb_hdr;
#endif
- DEBUG_START_HWTRACE(p5, r7)
+ DEBUG_HWTRACE_RESTORE(p5, r7)
RESTORE_ALL_SYS
SP = EX_SCRATCH_REG;
rtx;
ENDPROC(_ex_icplb_miss)
ENTRY(_ex_syscall)
- DEBUG_START_HWTRACE(p5, r7)
(R7:6,P5:4) = [sp++];
ASTAT = [sp++];
raise 15; /* invoked by TRAP #0, for sys call */
@@ -178,7 +178,6 @@
ENDPROC(_ex_single_step)
ENTRY(_bfin_return_from_exception)
- DEBUG_START_HWTRACE(p5, r7)
#if ANOMALY_05000257
R7=LC0;
LC0=R7;
@@ -200,10 +199,9 @@
* need to make a CPLB exception look like a normal exception
*/
- DEBUG_START_HWTRACE(p5, r7)
RESTORE_ALL_SYS
[--sp] = ASTAT;
- [--sp] = (R7:6, P5:4);
+ [--sp] = (R7:6,P5:4);
ENTRY(_ex_replaceable)
nop;
@@ -253,7 +251,6 @@
R6 = SEQSTAT;
[P5] = R6;
- DEBUG_START_HWTRACE(p5, r7)
(R7:6,P5:4) = [sp++];
ASTAT = [sp++];
SP = EX_SCRATCH_REG;
@@ -382,8 +379,7 @@
sp.h = _exception_stack_top;
/* Try to deal with syscalls quickly. */
[--sp] = ASTAT;
- [--sp] = (R7:6, P5:4);
- DEBUG_STOP_HWTRACE(p5, r7)
+ [--sp] = (R7:6,P5:4);
r7 = SEQSTAT; /* reason code is in bit 5:0 */
r6.l = lo(SEQSTAT_EXCAUSE);
r6.h = hi(SEQSTAT_EXCAUSE);
diff --git a/include/asm-blackfin/trace.h b/include/asm-blackfin/trace.h
index 6313aac..ef18afb 100644
--- a/include/asm-blackfin/trace.h
+++ b/include/asm-blackfin/trace.h
@@ -46,42 +46,47 @@
#ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
-#define TRACE_BUFFER_START(preg, dreg) trace_buffer_start(preg, dreg)
-#define TRACE_BUFFER_STOP(preg, dreg) trace_buffer_stop(preg, dreg)
-
#define trace_buffer_stop(preg, dreg) \
preg.L = LO(TBUFCTL); \
preg.H = HI(TBUFCTL); \
dreg = 0x1; \
[preg] = dreg;
-#define trace_buffer_start(preg, dreg) \
- preg.L = LO(TBUFCTL); \
- preg.H = HI(TBUFCTL); \
- dreg = BFIN_TRACE_ON; \
- [preg] = dreg;
-
#define trace_buffer_init(preg, dreg) \
preg.L = LO(TBUFCTL); \
preg.H = HI(TBUFCTL); \
dreg = BFIN_TRACE_INIT; \
[preg] = dreg;
+#define trace_buffer_save(preg, dreg) \
+ preg.L = LO(TBUFCTL); \
+ preg.H = HI(TBUFCTL); \
+ dreg = [preg]; \
+ [sp++] = dreg; \
+ dreg = 0x1; \
+ [preg] = dreg;
+
+#define trace_buffer_restore(preg, dreg) \
+ preg.L = LO(TBUFCTL); \
+ preg.H = HI(TBUFCTL); \
+ dreg = [sp--]; \
+ [preg] = dreg;
+
#else /* CONFIG_DEBUG_BFIN_HWTRACE_ON */
#define trace_buffer_stop(preg, dreg)
-#define trace_buffer_start(preg, dreg)
#define trace_buffer_init(preg, dreg)
+#define trace_buffer_save(preg, dreg)
+#define trace_buffer_restore(preg, dreg)
#endif /* CONFIG_DEBUG_BFIN_HWTRACE_ON */
#ifdef CONFIG_DEBUG_BFIN_NO_KERN_HWTRACE
-# define DEBUG_START_HWTRACE(preg, dreg) trace_buffer_start(preg, dreg)
-# define DEBUG_STOP_HWTRACE(preg, dreg) trace_buffer_stop(preg, dreg)
-
+# define DEBUG_HWTRACE_SAVE(preg, dreg) trace_buffer_save(preg, dreg)
+# define DEBUG_HWTRACE_RESTORE(preg, dreg) trace_buffer_restore(preg, dreg)
#else
-# define DEBUG_START_HWTRACE(preg, dreg)
-# define DEBUG_STOP_HWTRACE(preg, dreg)
+# define DEBUG_HWTRACE_SAVE(preg, dreg)
+# define DEBUG_HWTRACE_RESTORE(preg, dreg)
#endif
#endif /* __ASSEMBLY__ */