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Diffstat (limited to 'arch/arm/kernel/smp_twd.c')
-rw-r--r--arch/arm/kernel/smp_twd.c88
1 files changed, 55 insertions, 33 deletions
diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c
index 25956204ef23..6591e26fc13f 100644
--- a/arch/arm/kernel/smp_twd.c
+++ b/arch/arm/kernel/smp_twd.c
@@ -11,6 +11,7 @@
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/clk.h>
+#include <linux/cpu.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/err.h>
@@ -24,7 +25,6 @@
#include <asm/smp_plat.h>
#include <asm/smp_twd.h>
-#include <asm/localtimer.h>
/* set up by the platform code */
static void __iomem *twd_base;
@@ -33,7 +33,7 @@ static struct clk *twd_clk;
static unsigned long twd_timer_rate;
static DEFINE_PER_CPU(bool, percpu_setup_called);
-static struct clock_event_device __percpu **twd_evt;
+static struct clock_event_device __percpu *twd_evt;
static int twd_ppi;
static void twd_set_mode(enum clock_event_mode mode,
@@ -45,7 +45,7 @@ static void twd_set_mode(enum clock_event_mode mode,
case CLOCK_EVT_MODE_PERIODIC:
ctrl = TWD_TIMER_CONTROL_ENABLE | TWD_TIMER_CONTROL_IT_ENABLE
| TWD_TIMER_CONTROL_PERIODIC;
- __raw_writel(DIV_ROUND_CLOSEST(twd_timer_rate, HZ),
+ writel_relaxed(DIV_ROUND_CLOSEST(twd_timer_rate, HZ),
twd_base + TWD_TIMER_LOAD);
break;
case CLOCK_EVT_MODE_ONESHOT:
@@ -58,18 +58,18 @@ static void twd_set_mode(enum clock_event_mode mode,
ctrl = 0;
}
- __raw_writel(ctrl, twd_base + TWD_TIMER_CONTROL);
+ writel_relaxed(ctrl, twd_base + TWD_TIMER_CONTROL);
}
static int twd_set_next_event(unsigned long evt,
struct clock_event_device *unused)
{
- unsigned long ctrl = __raw_readl(twd_base + TWD_TIMER_CONTROL);
+ unsigned long ctrl = readl_relaxed(twd_base + TWD_TIMER_CONTROL);
ctrl |= TWD_TIMER_CONTROL_ENABLE;
- __raw_writel(evt, twd_base + TWD_TIMER_COUNTER);
- __raw_writel(ctrl, twd_base + TWD_TIMER_CONTROL);
+ writel_relaxed(evt, twd_base + TWD_TIMER_COUNTER);
+ writel_relaxed(ctrl, twd_base + TWD_TIMER_CONTROL);
return 0;
}
@@ -82,16 +82,18 @@ static int twd_set_next_event(unsigned long evt,
*/
static int twd_timer_ack(void)
{
- if (__raw_readl(twd_base + TWD_TIMER_INTSTAT)) {
- __raw_writel(1, twd_base + TWD_TIMER_INTSTAT);
+ if (readl_relaxed(twd_base + TWD_TIMER_INTSTAT)) {
+ writel_relaxed(1, twd_base + TWD_TIMER_INTSTAT);
return 1;
}
return 0;
}
-static void twd_timer_stop(struct clock_event_device *clk)
+static void twd_timer_stop(void)
{
+ struct clock_event_device *clk = __this_cpu_ptr(twd_evt);
+
twd_set_mode(CLOCK_EVT_MODE_UNUSED, clk);
disable_percpu_irq(clk->irq);
}
@@ -106,7 +108,7 @@ static void twd_update_frequency(void *new_rate)
{
twd_timer_rate = *((unsigned long *) new_rate);
- clockevents_update_freq(*__this_cpu_ptr(twd_evt), twd_timer_rate);
+ clockevents_update_freq(__this_cpu_ptr(twd_evt), twd_timer_rate);
}
static int twd_rate_change(struct notifier_block *nb,
@@ -132,7 +134,7 @@ static struct notifier_block twd_clk_nb = {
static int twd_clk_init(void)
{
- if (twd_evt && *__this_cpu_ptr(twd_evt) && !IS_ERR(twd_clk))
+ if (twd_evt && __this_cpu_ptr(twd_evt) && !IS_ERR(twd_clk))
return clk_notifier_register(twd_clk, &twd_clk_nb);
return 0;
@@ -151,7 +153,7 @@ static void twd_update_frequency(void *data)
{
twd_timer_rate = clk_get_rate(twd_clk);
- clockevents_update_freq(*__this_cpu_ptr(twd_evt), twd_timer_rate);
+ clockevents_update_freq(__this_cpu_ptr(twd_evt), twd_timer_rate);
}
static int twd_cpufreq_transition(struct notifier_block *nb,
@@ -177,7 +179,7 @@ static struct notifier_block twd_cpufreq_nb = {
static int twd_cpufreq_init(void)
{
- if (twd_evt && *__this_cpu_ptr(twd_evt) && !IS_ERR(twd_clk))
+ if (twd_evt && __this_cpu_ptr(twd_evt) && !IS_ERR(twd_clk))
return cpufreq_register_notifier(&twd_cpufreq_nb,
CPUFREQ_TRANSITION_NOTIFIER);
@@ -209,15 +211,15 @@ static void twd_calibrate_rate(void)
waitjiffies += 5;
/* enable, no interrupt or reload */
- __raw_writel(0x1, twd_base + TWD_TIMER_CONTROL);
+ writel_relaxed(0x1, twd_base + TWD_TIMER_CONTROL);
/* maximum value */
- __raw_writel(0xFFFFFFFFU, twd_base + TWD_TIMER_COUNTER);
+ writel_relaxed(0xFFFFFFFFU, twd_base + TWD_TIMER_COUNTER);
while (get_jiffies_64() < waitjiffies)
udelay(10);
- count = __raw_readl(twd_base + TWD_TIMER_COUNTER);
+ count = readl_relaxed(twd_base + TWD_TIMER_COUNTER);
twd_timer_rate = (0xFFFFFFFFU - count) * (HZ / 5);
@@ -228,7 +230,7 @@ static void twd_calibrate_rate(void)
static irqreturn_t twd_handler(int irq, void *dev_id)
{
- struct clock_event_device *evt = *(struct clock_event_device **)dev_id;
+ struct clock_event_device *evt = dev_id;
if (twd_timer_ack()) {
evt->event_handler(evt);
@@ -265,9 +267,9 @@ static void twd_get_clock(struct device_node *np)
/*
* Setup the local clock events for a CPU.
*/
-static int twd_timer_setup(struct clock_event_device *clk)
+static void twd_timer_setup(void)
{
- struct clock_event_device **this_cpu_clk;
+ struct clock_event_device *clk = __this_cpu_ptr(twd_evt);
int cpu = smp_processor_id();
/*
@@ -275,10 +277,10 @@ static int twd_timer_setup(struct clock_event_device *clk)
* bother with the below.
*/
if (per_cpu(percpu_setup_called, cpu)) {
- __raw_writel(0, twd_base + TWD_TIMER_CONTROL);
- clockevents_register_device(*__this_cpu_ptr(twd_evt));
+ writel_relaxed(0, twd_base + TWD_TIMER_CONTROL);
+ clockevents_register_device(clk);
enable_percpu_irq(clk->irq, 0);
- return 0;
+ return;
}
per_cpu(percpu_setup_called, cpu) = true;
@@ -288,7 +290,7 @@ static int twd_timer_setup(struct clock_event_device *clk)
* The following is done once per CPU the first time .setup() is
* called.
*/
- __raw_writel(0, twd_base + TWD_TIMER_CONTROL);
+ writel_relaxed(0, twd_base + TWD_TIMER_CONTROL);
clk->name = "local_timer";
clk->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT |
@@ -297,27 +299,37 @@ static int twd_timer_setup(struct clock_event_device *clk)
clk->set_mode = twd_set_mode;
clk->set_next_event = twd_set_next_event;
clk->irq = twd_ppi;
-
- this_cpu_clk = __this_cpu_ptr(twd_evt);
- *this_cpu_clk = clk;
+ clk->cpumask = cpumask_of(cpu);
clockevents_config_and_register(clk, twd_timer_rate,
0xf, 0xffffffff);
enable_percpu_irq(clk->irq, 0);
+}
- return 0;
+static int twd_timer_cpu_notify(struct notifier_block *self,
+ unsigned long action, void *hcpu)
+{
+ switch (action & ~CPU_TASKS_FROZEN) {
+ case CPU_STARTING:
+ twd_timer_setup();
+ break;
+ case CPU_DYING:
+ twd_timer_stop();
+ break;
+ }
+
+ return NOTIFY_OK;
}
-static struct local_timer_ops twd_lt_ops = {
- .setup = twd_timer_setup,
- .stop = twd_timer_stop,
+static struct notifier_block twd_timer_cpu_nb = {
+ .notifier_call = twd_timer_cpu_notify,
};
static int __init twd_local_timer_common_register(struct device_node *np)
{
int err;
- twd_evt = alloc_percpu(struct clock_event_device *);
+ twd_evt = alloc_percpu(struct clock_event_device);
if (!twd_evt) {
err = -ENOMEM;
goto out_free;
@@ -329,12 +341,22 @@ static int __init twd_local_timer_common_register(struct device_node *np)
goto out_free;
}
- err = local_timer_register(&twd_lt_ops);
+ err = register_cpu_notifier(&twd_timer_cpu_nb);
if (err)
goto out_irq;
twd_get_clock(np);
+ /*
+ * Immediately configure the timer on the boot CPU, unless we need
+ * jiffies to be incrementing to calibrate the rate in which case
+ * setup the timer in late_time_init.
+ */
+ if (twd_timer_rate)
+ twd_timer_setup();
+ else
+ late_time_init = twd_timer_setup;
+
return 0;
out_irq:
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-27 01:56:30 +0000