diff options
| author | Rick Chen <rickchen36@gmail.com> | 2017-12-12 06:12:21 +0100 |
|---|---|---|
| committer | Greentime Hu <greentime@andestech.com> | 2018-02-22 03:44:36 +0100 |
| commit | ea4625c3860ba002c83b1dffc528e1a4f0a89cf5 (patch) | |
| tree | 9d3ffbbbb47f114d1b53af9e238658013a86e1bd /drivers/clocksource | |
| parent | clocksource/drivers/atcpit100: Add andestech atcpit100 timer (diff) | |
| download | linux-ea4625c3860ba002c83b1dffc528e1a4f0a89cf5.tar.xz linux-ea4625c3860ba002c83b1dffc528e1a4f0a89cf5.zip | |
clocksource/drivers/atcpit100: VDSO support
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 <vincentc@andestech.com>
Signed-off-by: Rick Chen <rickchen36@gmail.com>
Signed-off-by: Greentime Hu <green.hu@gmail.com>
Diffstat (limited to 'drivers/clocksource')
| -rw-r--r-- | drivers/clocksource/timer-atcpit100.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-atcpit100.c b/drivers/clocksource/timer-atcpit100.c index 2190096cffa3..5e23d7b4a722 100644 --- a/drivers/clocksource/timer-atcpit100.c +++ b/drivers/clocksource/timer-atcpit100.c @@ -18,6 +18,9 @@ #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 @@ -204,6 +207,17 @@ 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(struct device_node *node) +{ + struct resource timer_res; + of_address_to_resource(node, 0, &timer_res); + timer_info.mapping_base = (unsigned long)timer_res.start; + 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; @@ -242,6 +256,10 @@ 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(node); +#endif + return ret; } |