ARM: 6319/1: ftrace: add Thumb-2 support to dynamic ftrace
Handle the different nop and call instructions for Thumb-2. Also, we
need to adjust the recorded mcount_loc addresses because they have the
lsb set.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org> [recordmcount.pl change]
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/kernel/ftrace.c b/arch/arm/kernel/ftrace.c
index f09014c..971ac8c 100644
--- a/arch/arm/kernel/ftrace.c
+++ b/arch/arm/kernel/ftrace.c
@@ -18,7 +18,11 @@
#include <asm/cacheflush.h>
#include <asm/ftrace.h>
+#ifdef CONFIG_THUMB2_KERNEL
+#define NOP 0xeb04f85d /* pop.w {lr} */
+#else
#define NOP 0xe8bd4000 /* pop {lr} */
+#endif
#ifdef CONFIG_OLD_MCOUNT
#define OLD_MCOUNT_ADDR ((unsigned long) mcount)
@@ -56,6 +60,34 @@
#endif
/* construct a branch (BL) instruction to addr */
+#ifdef CONFIG_THUMB2_KERNEL
+static unsigned long ftrace_call_replace(unsigned long pc, unsigned long addr)
+{
+ unsigned long s, j1, j2, i1, i2, imm10, imm11;
+ unsigned long first, second;
+ long offset;
+
+ offset = (long)addr - (long)(pc + 4);
+ if (offset < -16777216 || offset > 16777214) {
+ WARN_ON_ONCE(1);
+ return 0;
+ }
+
+ s = (offset >> 24) & 0x1;
+ i1 = (offset >> 23) & 0x1;
+ i2 = (offset >> 22) & 0x1;
+ imm10 = (offset >> 12) & 0x3ff;
+ imm11 = (offset >> 1) & 0x7ff;
+
+ j1 = (!i1) ^ s;
+ j2 = (!i2) ^ s;
+
+ first = 0xf000 | (s << 10) | imm10;
+ second = 0xd000 | (j1 << 13) | (j2 << 11) | imm11;
+
+ return (second << 16) | first;
+}
+#else
static unsigned long ftrace_call_replace(unsigned long pc, unsigned long addr)
{
long offset;
@@ -73,6 +105,7 @@
return 0xeb000000 | offset;
}
+#endif
static int ftrace_modify_code(unsigned long pc, unsigned long old,
unsigned long new)
