[PATCH v5 2/3] clocksource/drivers/atcpit100: VDSO support
From: Rick Chen <hidden>
Date: 2017-12-12 06:12:22
Also in:
linux-devicetree, linux-serial, lkml, netdev
Subsystem:
clocksource, clockevent drivers, the rest · Maintainers:
Daniel Lezcano, Thomas Gleixner, Linus Torvalds
VDSO needs real-time cycle count to ensure the time accuracy. Unlike others, nds32 architecture does not define clock source, hence VDSO needs atcpit100 offering real-time cycle count to derive the correct time. Signed-off-by: Vincent Chen <redacted> Signed-off-by: Rick Chen <redacted> Signed-off-by: Greentime Hu <redacted> --- drivers/clocksource/timer-atcpit100.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+)
diff --git a/drivers/clocksource/timer-atcpit100.c b/drivers/clocksource/timer-atcpit100.c
index 0077fdb..1be6c0a 100644
--- a/drivers/clocksource/timer-atcpit100.c
+++ b/drivers/clocksource/timer-atcpit100.c@@ -29,6 +29,9 @@ #include <linux/of_irq.h> #include <linux/of_platform.h> #include "timer-of.h" +#ifdef CONFIG_NDS32 +#include <asm/vdso_timer_info.h> +#endif /* * Definition of register offsets
@@ -211,6 +214,14 @@ static u64 notrace atcpit100_timer_sched_read(void) return ~readl(timer_of_base(&to) + CH1_CNT); } +#ifdef CONFIG_NDS32 +static void fill_vdso_need_info(void) +{ + timer_info.cycle_count_down = true; + timer_info.cycle_count_reg_offset = CH1_CNT; +} +#endif + static int __init atcpit100_timer_init(struct device_node *node) { int ret;
@@ -249,6 +260,10 @@ static int __init atcpit100_timer_init(struct device_node *node) val = readl(base + INT_EN); writel(val | CH0INT0EN, base + INT_EN); +#ifdef CONFIG_NDS32 + fill_vdso_need_info(); +#endif + return ret; }
--
2.7.4