sh: ftrace support.
This adds support for ftrace to SH. This only includes CONFIG_FTRACE,
and does not handle dynamic ftrace presently.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/kernel/entry-common.S b/arch/sh/kernel/entry-common.S
index efbb426..1a5cf9d 100644
--- a/arch/sh/kernel/entry-common.S
+++ b/arch/sh/kernel/entry-common.S
@@ -371,3 +371,47 @@
#endif
7: .long do_syscall_trace_enter
8: .long do_syscall_trace_leave
+
+#ifdef CONFIG_FTRACE
+ .align 2
+ .globl _mcount
+ .type _mcount,@function
+ .globl mcount
+ .type mcount,@function
+_mcount:
+mcount:
+ mov.l r4, @-r15
+ mov.l r5, @-r15
+ mov.l r6, @-r15
+ mov.l r7, @-r15
+ sts.l pr, @-r15
+
+ mov.l @(20,r15),r4
+ sts pr, r5
+
+ mov.l 1f, r6
+ mov.l ftrace_stub, r7
+ cmp/eq r6, r7
+ bt skip_trace
+
+ mov.l @r6, r6
+ jsr @r6
+ nop
+
+skip_trace:
+
+ lds.l @r15+, pr
+ mov.l @r15+, r7
+ mov.l @r15+, r6
+ mov.l @r15+, r5
+ rts
+ mov.l @r15+, r4
+
+ .align 2
+1: .long ftrace_trace_function
+
+ .globl ftrace_stub
+ftrace_stub:
+ rts
+ nop
+#endif /* CONFIG_FTRACE */