[PATCH 1/1] arm64: enable processor debug state for secondary cpus

[vijay.kilari at gmail.com]

From: Vijaya Kumar K <Vijaya.Kumar at caviumnetworks.com>

processor debug state PSTATE.D is unmasked in smp call
clear_os_lock for secondary cpus. So debug state is still
masked in normal kernel context.  With this patch, unmask
debug state on secondary boot for the cpus in normal kernel
context. Now kgdb tests passed with multicore.

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar at caviumnetworks.com>
Acked-by: Will Deacon <will.deacon at arm.com>
---
 arch/arm64/kernel/debug-monitors.c |    7 +++----
 arch/arm64/kernel/smp.c            |    1 +
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c
index 1a8127d..13f87de 100644
--- a/arch/arm64/kernel/debug-monitors.c
+++ b/arch/arm64/kernel/debug-monitors.c
@@ -137,8 +137,6 @@ void disable_debug_monitors(enum debug_el el)
 static void clear_os_lock(void *unused)
 {
 	asm volatile("msr oslar_el1, %0" : : "r" (0));
-	isb();
-	local_dbg_enable();
 }
 
 static int os_lock_notify(struct notifier_block *self,
@@ -157,8 +155,9 @@ static struct notifier_block os_lock_nb = {
 static int debug_monitors_init(void)
 {
 	/* Clear the OS lock. */
-	smp_call_function(clear_os_lock, NULL, 1);
-	clear_os_lock(NULL);
+	on_each_cpu(clear_os_lock, NULL, 1);
+	isb();
+	local_dbg_enable();
 
 	/* Register hotplug handler. */
 	register_cpu_notifier(&os_lock_nb);
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index 7cfb92a..5070dc3 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -160,6 +160,7 @@ asmlinkage void secondary_start_kernel(void)
 	set_cpu_online(cpu, true);
 	complete(&cpu_running);
 
+	local_dbg_enable();
 	local_irq_enable();
 	local_async_enable();
 
-- 
1.7.9.5