From: Fu Wei fu.wei@linaro.org
When system init with device-tree, we don't know which node will be initialized first. And the code in arch_timer_common_init should wait until per-cpu timer and MMIO timer are both initialized. So we need arch_timer_needs_probing to detect the init status of system.
But currently the code is dispersed in arch_timer_needs_probing and arch_timer_common_init. And the function name doesn't specify that it's only for device-tree. This is somewhat confusing.
This patch move all related code from arch_timer_common_init to arch_timer_needs_probing, refactor it, and rename it to arch_timer_needs_of_probing. And make sure that it will be called only if acpi is disabled.
Signed-off-by: Fu Wei fu.wei@linaro.org Reviewed-by: Hanjun Guo hanjun.guo@linaro.org --- drivers/clocksource/arm_arch_timer.c | 34 +++++++++++++++++++--------------- 1 file changed, 19 insertions(+), 15 deletions(-)
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index 29ca7d6..d1a05d9 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -839,15 +839,28 @@ static const struct of_device_id arch_timer_mem_of_match[] __initconst = { {}, };
-static bool __init -arch_timer_needs_probing(int type, const struct of_device_id *matches) +static bool __init arch_timer_needs_of_probing(void) { struct device_node *dn; bool needs_probing = false; + unsigned int mask = ARCH_TIMER_TYPE_CP15 | ARCH_TIMER_TYPE_MEM;
- dn = of_find_matching_node(NULL, matches); - if (dn && of_device_is_available(dn) && !(arch_timers_present & type)) + /* We have two timers, and both device-tree nodes are probed. */ + if ((arch_timers_present & mask) == mask) + return false; + + /* + * Only one type of timer is probed, + * check if we have another type of timer node in device-tree. + */ + if (arch_timers_present & ARCH_TIMER_TYPE_CP15) + dn = of_find_matching_node(NULL, arch_timer_mem_of_match); + else + dn = of_find_matching_node(NULL, arch_timer_of_match); + + if (dn && of_device_is_available(dn)) needs_probing = true; + of_node_put(dn);
return needs_probing; @@ -855,17 +868,8 @@ arch_timer_needs_probing(int type, const struct of_device_id *matches)
static int __init arch_timer_common_init(void) { - unsigned mask = ARCH_TIMER_TYPE_CP15 | ARCH_TIMER_TYPE_MEM; - - /* Wait until both nodes are probed if we have two timers */ - if ((arch_timers_present & mask) != mask) { - if (arch_timer_needs_probing(ARCH_TIMER_TYPE_MEM, - arch_timer_mem_of_match)) - return 0; - if (arch_timer_needs_probing(ARCH_TIMER_TYPE_CP15, - arch_timer_of_match)) - return 0; - } + if (acpi_disabled && arch_timer_needs_of_probing()) + return 0;
arch_timer_banner(arch_timers_present); arch_counter_register(arch_timers_present);