[PATCH v20 07/17] clocksource/drivers/arm_arch_timer: Separate out device-tree code from arch_timer_detect_rate

fu.wei
2017-01-18T13:25:31Z

From: Fu Wei <fu.wei@linaro.org>

Currently, the counter frequency detection call(arch_timer_detect_rate)
include getting the frequency from the device-tree property.
But reading device-tree property will be needed only when system boot with
device-tree.

This patch separate out device-tree code, keep them in device-tree init
function.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
---
drivers/clocksource/arm_arch_timer.c | 38 ++++++++++++++++++++++--------------
1 file changed, 23 insertions(+), 15 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 674d89f..6484f84 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -488,24 +488,19 @@ static int arch_timer_starting_cpu(unsigned int cpu)
return 0;
}

-static void
-arch_timer_detect_rate(void __iomem *cntbase, struct device_node *np)
+static void arch_timer_detect_rate(void __iomem *cntbase)
{
/* Who has more than one independent system counter? */
if (arch_timer_rate)
return;

/*
- * Try to determine the frequency from the device tree or CNTFRQ,
- * if ACPI is enabled, get the frequency from CNTFRQ ONLY.
+ * Try to determine the frequency from the MMIO timer or the sysreg.
*/
- if (!acpi_disabled ||
- of_property_read_u32(np, "clock-frequency", &arch_timer_rate)) {
- if (cntbase)
- arch_timer_rate = readl_relaxed(cntbase + CNTFRQ);
- else
- arch_timer_rate = arch_timer_get_cntfrq();
- }
+ if (cntbase)
+ arch_timer_rate = readl_relaxed(cntbase + CNTFRQ);
+ else
+ arch_timer_rate = arch_timer_get_cntfrq();

/* Check the timer frequency. */
if (arch_timer_rate == 0)
@@ -886,7 +881,13 @@ static int __init arch_timer_of_init(struct device_node *np)
for (i = ARCH_TIMER_PHYS_SECURE_PPI; i < ARCH_TIMER_MAX_TIMER_PPI; i++)
arch_timer_ppi[i] = irq_of_parse_and_map(np, i);

- arch_timer_detect_rate(NULL, np);
+ /*
+ * Try to determine the frequency from the device tree,
+ * if fail, get the frequency from the sysreg CNTFRQ.
+ */
+ if (!arch_timer_rate &&
+ of_property_read_u32(np, "clock-frequency", &arch_timer_rate))
+ arch_timer_detect_rate(NULL);

arch_timer_c3stop = !of_property_read_bool(np, "always-on");

@@ -994,7 +995,14 @@ static int __init arch_timer_mem_init(struct device_node *np)
goto out;
}

- arch_timer_detect_rate(base, np);
+ /*
+ * Try to determine the frequency from the device tree,
+ * if fail, get the frequency from the CNTFRQ reg of MMIO timer.
+ */
+ if (!arch_timer_rate &&
+ of_property_read_u32(np, "clock-frequency", &arch_timer_rate))
+ arch_timer_detect_rate(base);
+
ret = arch_timer_mem_register(base, irq);
if (ret)
goto out;
@@ -1055,8 +1063,8 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table)
map_generic_timer_interrupt(gtdt->non_secure_el2_interrupt,
gtdt->non_secure_el2_flags);

- /* Get the frequency from CNTFRQ */
- arch_timer_detect_rate(NULL, NULL);
+ /* Get the frequency from the sysreg CNTFRQ */
+ arch_timer_detect_rate(NULL);

arch_timer_uses_ppi = arch_timer_select_ppi();
if (!arch_timer_ppi[arch_timer_uses_ppi]) {
--
2.9.3