1 From 3b3c2406dd9797bc806e0ce756142a33d209c4e8 Mon Sep 17 00:00:00 2001
2 From: "Joe.C" <yingjoe.chen@mediatek.com>
3 Date: Fri, 1 May 2015 15:43:25 +0800
4 Subject: [PATCH 40/76] clocksource: mediatek: Use GPT as sched clock source
6 When cpu is in deep idle, arch timer will stop counting. Setup GPT as
7 sched clock source so it can keep counting in idle.
9 Signed-off-by: Yingjoe Chen <yingjoe.chen@mediatek.com>
11 drivers/clocksource/mtk_timer.c | 10 ++++++++++
12 1 file changed, 10 insertions(+)
14 diff --git a/drivers/clocksource/mtk_timer.c b/drivers/clocksource/mtk_timer.c
15 index 85e0ab5..9a90c7b 100644
16 --- a/drivers/clocksource/mtk_timer.c
17 +++ b/drivers/clocksource/mtk_timer.c
20 #include <linux/of_address.h>
21 #include <linux/of_irq.h>
22 +#include <linux/sched_clock.h>
23 #include <linux/slab.h>
25 #define GPT_IRQ_EN_REG 0x00
26 @@ -59,6 +60,13 @@ struct mtk_clock_event_device {
27 struct clock_event_device dev;
30 +static void __iomem *gpt_base __read_mostly;
32 +static u64 notrace mtk_read_sched_clock(void)
34 + return readl_relaxed(gpt_base + TIMER_CNT_REG(GPT_CLK_SRC));
37 static inline struct mtk_clock_event_device *to_mtk_clk(
38 struct clock_event_device *c)
40 @@ -239,6 +247,8 @@ static void __init mtk_timer_init(struct device_node *node)
41 mtk_timer_setup(evt, GPT_CLK_SRC, TIMER_CTRL_OP_FREERUN);
42 clocksource_mmio_init(evt->gpt_base + TIMER_CNT_REG(GPT_CLK_SRC),
43 node->name, rate, 300, 32, clocksource_mmio_readl_up);
44 + gpt_base = evt->gpt_base;
45 + sched_clock_register(mtk_read_sched_clock, 32, rate);
47 /* Configure clock event */
48 mtk_timer_setup(evt, GPT_CLK_EVT, TIMER_CTRL_OP_REPEAT);