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path: root/drivers/clocksource/arm_global_timer.c
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Diffstat (limited to 'drivers/clocksource/arm_global_timer.c')
-rw-r--r--drivers/clocksource/arm_global_timer.c35
1 files changed, 16 insertions, 19 deletions
diff --git a/drivers/clocksource/arm_global_timer.c b/drivers/clocksource/arm_global_timer.c
index 44a61dc6f93208..ab1c8c2b66b887 100644
--- a/drivers/clocksource/arm_global_timer.c
+++ b/drivers/clocksource/arm_global_timer.c
@@ -9,6 +9,7 @@
#include <linux/init.h>
#include <linux/interrupt.h>
+#include <linux/bitfield.h>
#include <linux/clocksource.h>
#include <linux/clockchips.h>
#include <linux/cpu.h>
@@ -31,10 +32,7 @@
#define GT_CONTROL_COMP_ENABLE BIT(1) /* banked */
#define GT_CONTROL_IRQ_ENABLE BIT(2) /* banked */
#define GT_CONTROL_AUTO_INC BIT(3) /* banked */
-#define GT_CONTROL_PRESCALER_SHIFT 8
-#define GT_CONTROL_PRESCALER_MAX 0xF
-#define GT_CONTROL_PRESCALER_MASK (GT_CONTROL_PRESCALER_MAX << \
- GT_CONTROL_PRESCALER_SHIFT)
+#define GT_CONTROL_PRESCALER_MASK GENMASK(15, 8)
#define GT_INT_STATUS 0x0c
#define GT_INT_STATUS_EVENT_FLAG BIT(0)
@@ -52,7 +50,8 @@
*/
static void __iomem *gt_base;
static struct notifier_block gt_clk_rate_change_nb;
-static u32 gt_psv_new, gt_psv_bck, gt_target_rate;
+static u32 gt_psv_new, gt_psv_bck;
+static unsigned long gt_target_rate;
static int gt_ppi;
static struct clock_event_device __percpu *gt_evt;
@@ -88,7 +87,7 @@ static u64 gt_counter_read(void)
return _gt_counter_read();
}
-/**
+/*
* To ensure that updates to comparator value register do not set the
* Interrupt Status Register proceed as follows:
* 1. Clear the Comp Enable bit in the Timer Control Register.
@@ -247,7 +246,7 @@ static void gt_write_presc(u32 psv)
reg = readl(gt_base + GT_CONTROL);
reg &= ~GT_CONTROL_PRESCALER_MASK;
- reg |= psv << GT_CONTROL_PRESCALER_SHIFT;
+ reg |= FIELD_PREP(GT_CONTROL_PRESCALER_MASK, psv);
writel(reg, gt_base + GT_CONTROL);
}
@@ -256,8 +255,7 @@ static u32 gt_read_presc(void)
u32 reg;
reg = readl(gt_base + GT_CONTROL);
- reg &= GT_CONTROL_PRESCALER_MASK;
- return reg >> GT_CONTROL_PRESCALER_SHIFT;
+ return FIELD_GET(GT_CONTROL_PRESCALER_MASK, reg);
}
static void __init gt_delay_timer_init(void)
@@ -272,9 +270,9 @@ static int __init gt_clocksource_init(void)
writel(0, gt_base + GT_COUNTER0);
writel(0, gt_base + GT_COUNTER1);
/* set prescaler and enable timer on all the cores */
- writel(((CONFIG_ARM_GT_INITIAL_PRESCALER_VAL - 1) <<
- GT_CONTROL_PRESCALER_SHIFT)
- | GT_CONTROL_TIMER_ENABLE, gt_base + GT_CONTROL);
+ writel(FIELD_PREP(GT_CONTROL_PRESCALER_MASK,
+ CONFIG_ARM_GT_INITIAL_PRESCALER_VAL - 1) |
+ GT_CONTROL_TIMER_ENABLE, gt_base + GT_CONTROL);
#ifdef CONFIG_CLKSRC_ARM_GLOBAL_TIMER_SCHED_CLOCK
sched_clock_register(gt_sched_clock_read, 64, gt_target_rate);
@@ -290,18 +288,17 @@ static int gt_clk_rate_change_cb(struct notifier_block *nb,
switch (event) {
case PRE_RATE_CHANGE:
{
- int psv;
-
- psv = DIV_ROUND_CLOSEST(ndata->new_rate,
- gt_target_rate);
+ unsigned long psv;
- if (abs(gt_target_rate - (ndata->new_rate / psv)) > MAX_F_ERR)
+ psv = DIV_ROUND_CLOSEST(ndata->new_rate, gt_target_rate);
+ if (!psv ||
+ abs(gt_target_rate - (ndata->new_rate / psv)) > MAX_F_ERR)
return NOTIFY_BAD;
psv--;
/* prescaler within legal range? */
- if (psv < 0 || psv > GT_CONTROL_PRESCALER_MAX)
+ if (!FIELD_FIT(GT_CONTROL_PRESCALER_MASK, psv))
return NOTIFY_BAD;
/*
@@ -411,7 +408,7 @@ static int __init global_timer_of_register(struct device_node *np)
err = gt_clocksource_init();
if (err)
goto out_irq;
-
+
err = cpuhp_setup_state(CPUHP_AP_ARM_GLOBAL_TIMER_STARTING,
"clockevents/arm/global_timer:starting",
gt_starting_cpu, gt_dying_cpu);