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 Reviewed-by: Hanjun Guo hanjun.guo@linaro.org Tested-by: Hanjun Guo hanjun.guo@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 1d273d6..aa14305 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -571,24 +571,19 @@ static u32 arch_timer_get_mmio_freq(void __iomem *cntbase) return readl_relaxed(cntbase + CNTFRQ); }
-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 = arch_timer_get_mmio_freq(cntbase); - else - arch_timer_rate = arch_timer_get_sysreg_freq(); - } + if (cntbase) + arch_timer_rate = arch_timer_get_mmio_freq(cntbase); + else + arch_timer_rate = arch_timer_get_sysreg_freq();
/* Check the timer frequency. */ if (arch_timer_rate == 0) @@ -969,7 +964,13 @@ 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");
@@ -1080,7 +1081,14 @@ 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; @@ -1141,8 +1149,8 @@ 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]) {