diff options
| author | Se Wang (Patrick) Oh <sewango@codeaurora.org> | 2015-05-28 12:37:22 -0700 |
|---|---|---|
| committer | David Keitel <dkeitel@codeaurora.org> | 2016-03-22 11:08:51 -0700 |
| commit | a1c9d666be3e2c85c914b82cd1a201a3fd2be42d (patch) | |
| tree | 6c7cbdd28fcc2d91bd1fd36f39884bd35e37d746 /arch/arm/include | |
| parent | 56e8f397e636a792943c75b4766437b11bb49a28 (diff) | |
arm: traps: emulate a MRCC instruction reading CNTPCT register
A user space application is planned to support feature for
synchronized timestamp among debug packets across peripherals.
As part of the feature, it is responsible for providing physical
timer count value to user space. If memory mapped timer is used
in ARM arch, Usersapce can't read the physical timer count directly
with a MRCC ASM instruction. So Kernel traps the instruction and
returns the physical timer count.
Change-Id: Ia3f0d9c8c06ca9e2204187890c0c57c8640e4f7e
Signed-off-by: Se Wang (Patrick) Oh <sewango@codeaurora.org>
[abhimany: minor merge conflict resolution]
Signed-off-by: Abhimanyu Kapur <abhimany@codeaurora.org>
Diffstat (limited to 'arch/arm/include')
| -rw-r--r-- | arch/arm/include/asm/traps.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/arm/include/asm/traps.h b/arch/arm/include/asm/traps.h index f555bb3664dc..f9e412b97fbf 100644 --- a/arch/arm/include/asm/traps.h +++ b/arch/arm/include/asm/traps.h @@ -46,6 +46,7 @@ static inline int in_exception_text(unsigned long ptr) return in ? : __in_irqentry_text(ptr); } +extern void get_pct_hook_init(void); extern void __init early_trap_init(void *); extern void dump_backtrace_entry(unsigned long where, unsigned long from, unsigned long frame); extern void ptrace_break(struct task_struct *tsk, struct pt_regs *regs); |