Jetpack/kernel/kernel-4.9/rt-patches/0056-ARM-AT91-PIT-Remove-ir...

157 lines
4.9 KiB
Diff

From 9db3aeb5b324f5c13e1b1bf6e2d66493dc8a877f Mon Sep 17 00:00:00 2001
From: Benedikt Spranger <b.spranger@linutronix.de>
Date: Sat, 6 Mar 2010 17:47:10 +0100
Subject: [PATCH 056/352] ARM: AT91: PIT: Remove irq handler when clock event
is unused
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Setup and remove the interrupt handler in clock event mode selection.
This avoids calling the (shared) interrupt handler when the device is
not used.
Signed-off-by: Benedikt Spranger <b.spranger@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[bigeasy: redo the patch with NR_IRQS_LEGACY which is probably required since
commit 8fe82a55 ("ARM: at91: sparse irq support") which is included since v3.6.
Patch based on what Sami Pietikäinen <Sami.Pietikainen@wapice.com> suggested].
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
drivers/clocksource/timer-atmel-pit.c | 18 +++++++++---------
drivers/clocksource/timer-atmel-st.c | 34 ++++++++++++++++++++++------------
2 files changed, 31 insertions(+), 21 deletions(-)
diff --git a/drivers/clocksource/timer-atmel-pit.c b/drivers/clocksource/timer-atmel-pit.c
index 6555821..2c66bb3 100644
--- a/drivers/clocksource/timer-atmel-pit.c
+++ b/drivers/clocksource/timer-atmel-pit.c
@@ -96,15 +96,24 @@ static int pit_clkevt_shutdown(struct clock_event_device *dev)
/* disable irq, leaving the clocksource active */
pit_write(data->base, AT91_PIT_MR, (data->cycle - 1) | AT91_PIT_PITEN);
+ free_irq(data->irq, data);
return 0;
}
+static irqreturn_t at91sam926x_pit_interrupt(int irq, void *dev_id);
/*
* Clockevent device: interrupts every 1/HZ (== pit_cycles * MCK/16)
*/
static int pit_clkevt_set_periodic(struct clock_event_device *dev)
{
struct pit_data *data = clkevt_to_pit_data(dev);
+ int ret;
+
+ ret = request_irq(data->irq, at91sam926x_pit_interrupt,
+ IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
+ "at91_tick", data);
+ if (ret)
+ panic(pr_fmt("Unable to setup IRQ\n"));
/* update clocksource counter */
data->cnt += data->cycle * PIT_PICNT(pit_read(data->base, AT91_PIT_PIVR));
@@ -230,15 +239,6 @@ static int __init at91sam926x_pit_dt_init(struct device_node *node)
return ret;
}
- /* Set up irq handler */
- ret = request_irq(data->irq, at91sam926x_pit_interrupt,
- IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
- "at91_tick", data);
- if (ret) {
- pr_err("Unable to setup IRQ\n");
- return ret;
- }
-
/* Set up and register clockevents */
data->clkevt.name = "pit";
data->clkevt.features = CLOCK_EVT_FEAT_PERIODIC;
diff --git a/drivers/clocksource/timer-atmel-st.c b/drivers/clocksource/timer-atmel-st.c
index e90ab5b..9e12408 100644
--- a/drivers/clocksource/timer-atmel-st.c
+++ b/drivers/clocksource/timer-atmel-st.c
@@ -115,18 +115,29 @@ static void clkdev32k_disable_and_flush_irq(void)
last_crtr = read_CRTR();
}
+static int atmel_st_irq;
+
static int clkevt32k_shutdown(struct clock_event_device *evt)
{
clkdev32k_disable_and_flush_irq();
irqmask = 0;
regmap_write(regmap_st, AT91_ST_IER, irqmask);
+ free_irq(atmel_st_irq, regmap_st);
return 0;
}
static int clkevt32k_set_oneshot(struct clock_event_device *dev)
{
+ int ret;
+
clkdev32k_disable_and_flush_irq();
+ ret = request_irq(atmel_st_irq, at91rm9200_timer_interrupt,
+ IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
+ "at91_tick", regmap_st);
+ if (ret)
+ panic(pr_fmt("Unable to setup IRQ\n"));
+
/*
* ALM for oneshot irqs, set by next_event()
* before 32 seconds have passed.
@@ -139,8 +150,16 @@ static int clkevt32k_set_oneshot(struct clock_event_device *dev)
static int clkevt32k_set_periodic(struct clock_event_device *dev)
{
+ int ret;
+
clkdev32k_disable_and_flush_irq();
+ ret = request_irq(atmel_st_irq, at91rm9200_timer_interrupt,
+ IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
+ "at91_tick", regmap_st);
+ if (ret)
+ panic(pr_fmt("Unable to setup IRQ\n"));
+
/* PIT for periodic irqs; fixed rate of 1/HZ */
irqmask = AT91_ST_PITS;
regmap_write(regmap_st, AT91_ST_PIMR, timer_latch);
@@ -198,7 +217,7 @@ static int __init atmel_st_timer_init(struct device_node *node)
{
struct clk *sclk;
unsigned int sclk_rate, val;
- int irq, ret;
+ int ret;
regmap_st = syscon_node_to_regmap(node);
if (IS_ERR(regmap_st)) {
@@ -212,21 +231,12 @@ static int __init atmel_st_timer_init(struct device_node *node)
regmap_read(regmap_st, AT91_ST_SR, &val);
/* Get the interrupts property */
- irq = irq_of_parse_and_map(node, 0);
- if (!irq) {
+ atmel_st_irq = irq_of_parse_and_map(node, 0);
+ if (!atmel_st_irq) {
pr_err("Unable to get IRQ from DT\n");
return -EINVAL;
}
- /* Make IRQs happen for the system timer */
- ret = request_irq(irq, at91rm9200_timer_interrupt,
- IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
- "at91_tick", regmap_st);
- if (ret) {
- pr_err("Unable to setup IRQ\n");
- return ret;
- }
-
sclk = of_clk_get(node, 0);
if (IS_ERR(sclk)) {
pr_err("Unable to get slow clock\n");
--
2.7.4