selftests/powerpc: Add TM tcheck helpers in C

Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/tools/testing/selftests/powerpc/tm/tm.h b/tools/testing/selftests/powerpc/tm/tm.h
index 60318ba..2c8da74 100644
--- a/tools/testing/selftests/powerpc/tm/tm.h
+++ b/tools/testing/selftests/powerpc/tm/tm.h
@@ -52,4 +52,31 @@
 	return (__builtin_get_texasru() & 0x400000);
 }
 
+static inline int tcheck(void)
+{
+	long cr;
+	asm volatile ("tcheck 0" : "=r"(cr) : : "cr0");
+	return (cr >> 28) & 4;
+}
+
+static inline bool tcheck_doomed(void)
+{
+	return tcheck() & 8;
+}
+
+static inline bool tcheck_active(void)
+{
+	return tcheck() & 4;
+}
+
+static inline bool tcheck_suspended(void)
+{
+	return tcheck() & 2;
+}
+
+static inline bool tcheck_transactional(void)
+{
+	return tcheck() & 6;
+}
+
 #endif /* _SELFTESTS_POWERPC_TM_TM_H */