Blackfin arch: Clean up trace buffer handling, No major functional changes.

Turns on trace earlier, so crashes at kernel start should print out a
trace, making things easier to debug.

Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>

1 files changed, 52 insertions, 0 deletions

diff --git a/include/asm-blackfin/trace.h b/include/asm-blackfin/trace.h
new file mode 100644
index 000000000000..9c2474c9a589
--- /dev/null
+++ b/include/asm-blackfin/trace.h
@@ -0,0 +1,52 @@
+/*
+ * Common header file for blackfin family of processors.
+ *
+ */
+
+#ifndef _BLACKFIN_TRACE_
+#define _BLACKFIN_TRACE_
+
+#ifndef __ASSEMBLY__
+/* Trace Macros for C files */
+
+#define trace_buffer_save(x) \
+        do { \
+                (x) = bfin_read_TBUFCTL(); \
+                bfin_write_TBUFCTL((x) & ~TBUFEN); \
+        } while (0)
+
+#define trace_buffer_restore(x) \
+        do { \
+                bfin_write_TBUFCTL((x));        \
+        } while (0)
+
+#else
+/* Trace Macros for Assembly files */
+
+#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 = 0x13;                    \
+        [preg] = dreg;
+
+#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)
+
+#else
+# define DEBUG_START_HWTRACE(preg, dreg)
+# define DEBUG_STOP_HWTRACE(preg, dreg)
+#endif
+
+#endif /* __ASSEMBLY__ */
+
+#endif                          /* _BLACKFIN_TRACE_ */