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path: root/drivers/clocksource/timer-imx-tpm.c
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Diffstat (limited to 'drivers/clocksource/timer-imx-tpm.c')
-rw-r--r--drivers/clocksource/timer-imx-tpm.c36
1 files changed, 23 insertions, 13 deletions
diff --git a/drivers/clocksource/timer-imx-tpm.c b/drivers/clocksource/timer-imx-tpm.c
index c1d52d5264c2..92c025b70eb6 100644
--- a/drivers/clocksource/timer-imx-tpm.c
+++ b/drivers/clocksource/timer-imx-tpm.c
@@ -8,8 +8,6 @@
#include <linux/clocksource.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
-#include <linux/of_address.h>
-#include <linux/of_irq.h>
#include <linux/sched_clock.h>
#include "timer-of.h"
@@ -34,8 +32,8 @@
#define TPM_C0SC_CHF_MASK (0x1 << 7)
#define TPM_C0V 0x24
-static int counter_width;
-static void __iomem *timer_base;
+static int counter_width __ro_after_init;
+static void __iomem *timer_base __ro_after_init;
static inline void tpm_timer_disable(void)
{
@@ -63,13 +61,14 @@ static inline void tpm_irq_acknowledge(void)
writel(TPM_STATUS_CH0F, timer_base + TPM_STATUS);
}
-static struct delay_timer tpm_delay_timer;
-
static inline unsigned long tpm_read_counter(void)
{
return readl(timer_base + TPM_CNT);
}
+#if defined(CONFIG_ARM)
+static struct delay_timer tpm_delay_timer;
+
static unsigned long tpm_read_current_timer(void)
{
return tpm_read_counter();
@@ -79,24 +78,33 @@ static u64 notrace tpm_read_sched_clock(void)
{
return tpm_read_counter();
}
+#endif
static int tpm_set_next_event(unsigned long delta,
struct clock_event_device *evt)
{
- unsigned long next, now;
+ unsigned long next, prev, now;
- next = tpm_read_counter();
- next += delta;
+ prev = tpm_read_counter();
+ next = prev + delta;
writel(next, timer_base + TPM_C0V);
now = tpm_read_counter();
/*
+ * Need to wait CNT increase at least 1 cycle to make sure
+ * the C0V has been updated into HW.
+ */
+ if ((next & 0xffffffff) != readl(timer_base + TPM_C0V))
+ while (now == tpm_read_counter())
+ ;
+
+ /*
* NOTE: We observed in a very small probability, the bus fabric
* contention between GPU and A7 may results a few cycles delay
* of writing CNT registers which may cause the min_delta event got
* missed, so we need add a ETIME check here in case it happened.
*/
- return (int)(next - now) <= 0 ? -ETIME : 0;
+ return (now - prev) >= delta ? -ETIME : 0;
}
static int tpm_set_state_oneshot(struct clock_event_device *evt)
@@ -127,9 +135,9 @@ static irqreturn_t tpm_timer_interrupt(int irq, void *dev_id)
static struct timer_of to_tpm = {
.flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK,
.clkevt = {
- .name = "i.MX7ULP TPM Timer",
+ .name = "i.MX TPM Timer",
.rating = 200,
- .features = CLOCK_EVT_FEAT_ONESHOT,
+ .features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_DYNIRQ,
.set_state_shutdown = tpm_set_state_shutdown,
.set_state_oneshot = tpm_set_state_oneshot,
.set_next_event = tpm_set_next_event,
@@ -137,7 +145,7 @@ static struct timer_of to_tpm = {
},
.of_irq = {
.handler = tpm_timer_interrupt,
- .flags = IRQF_TIMER | IRQF_IRQPOLL,
+ .flags = IRQF_TIMER,
},
.of_clk = {
.name = "per",
@@ -146,12 +154,14 @@ static struct timer_of to_tpm = {
static int __init tpm_clocksource_init(void)
{
+#if defined(CONFIG_ARM)
tpm_delay_timer.read_current_timer = &tpm_read_current_timer;
tpm_delay_timer.freq = timer_of_rate(&to_tpm) >> 3;
register_current_timer_delay(&tpm_delay_timer);
sched_clock_register(tpm_read_sched_clock, counter_width,
timer_of_rate(&to_tpm) >> 3);
+#endif
return clocksource_mmio_init(timer_base + TPM_CNT,
"imx-tpm",