clocksource: arm_arch_timer: refactor arch_timer_needs_probing

When booting with DT, it's possible for timer nodes to be probed in any
order. Some common initialisation needs to occur after all nodes have
been probed, and arch_timer_common_init() has code to detect when this
has happened.

This logic is DT-specific, and it would be best to factor it out of the
common code that will be shared with ACPI.

This patch folds this into the existing arch_timer_needs_probing(),
which is renamed to arch_timer_needs_of_probing(), and no longer takes
any arguments. This is only called when using DT, and not when using
ACPI, which will have a deterministic probe order.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
[Mark: reword commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
This commit is contained in:
Fu Wei 2017-03-22 00:31:14 +08:00 committed by Mark Rutland
parent 5d3dfa96c7
commit 13bf6992fe
1 changed files with 19 additions and 15 deletions

View File

@ -1076,15 +1076,28 @@ 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;
@ -1092,17 +1105,8 @@ 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);