*
* Timer 0 is used as free-running clocksource, while timer 1 is
* used as clock_event_device.
+ *
+ * ---
+ * Clocksource driver for Armada 370 and Armada XP SoC.
+ * This driver implements one compatible string for each SoC, given
+ * each has its own characteristics:
+ *
+ * * Armada 370 has no 25 MHz fixed timer.
+ *
+ * * Armada XP cannot work properly without such 25 MHz fixed timer as
+ * doing otherwise leads to using a clocksource whose frequency varies
+ * when doing cpufreq frequency changes.
+ *
+ * See Documentation/devicetree/bindings/timer/marvell,armada-370-xp-timer.txt
*/
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/kernel.h>
#include <linux/clk.h>
+#include <linux/cpu.h>
#include <linux/timer.h>
#include <linux/clockchips.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/sched_clock.h>
-
-#include <asm/localtimer.h>
#include <linux/percpu.h>
+
/*
* Timer block registers.
*/
#define TIMER_CTRL_OFF 0x0000
-#define TIMER0_EN 0x0001
-#define TIMER0_RELOAD_EN 0x0002
-#define TIMER0_25MHZ 0x0800
+#define TIMER0_EN BIT(0)
+#define TIMER0_RELOAD_EN BIT(1)
+#define TIMER0_25MHZ BIT(11)
#define TIMER0_DIV(div) ((div) << 19)
-#define TIMER1_EN 0x0004
-#define TIMER1_RELOAD_EN 0x0008
-#define TIMER1_25MHZ 0x1000
+#define TIMER1_EN BIT(2)
+#define TIMER1_RELOAD_EN BIT(3)
+#define TIMER1_25MHZ BIT(12)
#define TIMER1_DIV(div) ((div) << 22)
#define TIMER_EVENTS_STATUS 0x0004
#define TIMER0_CLR_MASK (~0x1)
*/
static u32 ticks_per_jiffy;
-static struct clock_event_device __percpu **percpu_armada_370_xp_evt;
+static struct clock_event_device __percpu *armada_370_xp_evt;
+
+static void timer_ctrl_clrset(u32 clr, u32 set)
+{
+ writel((readl(timer_base + TIMER_CTRL_OFF) & ~clr) | set,
+ timer_base + TIMER_CTRL_OFF);
+}
+
+static void local_timer_ctrl_clrset(u32 clr, u32 set)
+{
+ writel((readl(local_base + TIMER_CTRL_OFF) & ~clr) | set,
+ local_base + TIMER_CTRL_OFF);
+}
static u64 notrace armada_370_xp_read_sched_clock(void)
{
armada_370_xp_clkevt_next_event(unsigned long delta,
struct clock_event_device *dev)
{
- u32 u;
/*
* Clear clockevent timer interrupt.
*/
/*
* Enable the timer.
*/
- u = readl(local_base + TIMER_CTRL_OFF);
- u = ((u & ~TIMER0_RELOAD_EN) | TIMER0_EN |
- TIMER0_DIV(TIMER_DIVIDER_SHIFT));
- writel(u, local_base + TIMER_CTRL_OFF);
-
+ local_timer_ctrl_clrset(TIMER0_RELOAD_EN,
+ TIMER0_EN | TIMER0_DIV(TIMER_DIVIDER_SHIFT));
return 0;
}
armada_370_xp_clkevt_mode(enum clock_event_mode mode,
struct clock_event_device *dev)
{
- u32 u;
-
if (mode == CLOCK_EVT_MODE_PERIODIC) {
/*
/*
* Enable timer.
*/
-
- u = readl(local_base + TIMER_CTRL_OFF);
-
- writel((u | TIMER0_EN | TIMER0_RELOAD_EN |
- TIMER0_DIV(TIMER_DIVIDER_SHIFT)),
- local_base + TIMER_CTRL_OFF);
+ local_timer_ctrl_clrset(0, TIMER0_RELOAD_EN |
+ TIMER0_EN |
+ TIMER0_DIV(TIMER_DIVIDER_SHIFT));
} else {
/*
* Disable timer.
*/
- u = readl(local_base + TIMER_CTRL_OFF);
- writel(u & ~TIMER0_EN, local_base + TIMER_CTRL_OFF);
+ local_timer_ctrl_clrset(TIMER0_EN, 0);
/*
* ACK pending timer interrupt.
}
}
-static struct clock_event_device armada_370_xp_clkevt = {
- .name = "armada_370_xp_per_cpu_tick",
- .features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC,
- .shift = 32,
- .rating = 300,
- .set_next_event = armada_370_xp_clkevt_next_event,
- .set_mode = armada_370_xp_clkevt_mode,
-};
+static int armada_370_xp_clkevt_irq;
static irqreturn_t armada_370_xp_timer_interrupt(int irq, void *dev_id)
{
/*
* ACK timer interrupt and call event handler.
*/
- struct clock_event_device *evt = *(struct clock_event_device **)dev_id;
+ struct clock_event_device *evt = dev_id;
writel(TIMER0_CLR_MASK, local_base + LCL_TIMER_EVENTS_STATUS);
evt->event_handler(evt);
/*
* Setup the local clock events for a CPU.
*/
-static int __cpuinit armada_370_xp_timer_setup(struct clock_event_device *evt)
+static int armada_370_xp_timer_setup(struct clock_event_device *evt)
{
- u32 u;
+ u32 clr = 0, set = 0;
int cpu = smp_processor_id();
- /* Use existing clock_event for cpu 0 */
- if (!smp_processor_id())
- return 0;
-
- u = readl(local_base + TIMER_CTRL_OFF);
if (timer25Mhz)
- writel(u | TIMER0_25MHZ, local_base + TIMER_CTRL_OFF);
+ set = TIMER0_25MHZ;
else
- writel(u & ~TIMER0_25MHZ, local_base + TIMER_CTRL_OFF);
-
- evt->name = armada_370_xp_clkevt.name;
- evt->irq = armada_370_xp_clkevt.irq;
- evt->features = armada_370_xp_clkevt.features;
- evt->shift = armada_370_xp_clkevt.shift;
- evt->rating = armada_370_xp_clkevt.rating,
+ clr = TIMER0_25MHZ;
+ local_timer_ctrl_clrset(clr, set);
+
+ evt->name = "armada_370_xp_per_cpu_tick",
+ evt->features = CLOCK_EVT_FEAT_ONESHOT |
+ CLOCK_EVT_FEAT_PERIODIC;
+ evt->shift = 32,
+ evt->rating = 300,
evt->set_next_event = armada_370_xp_clkevt_next_event,
evt->set_mode = armada_370_xp_clkevt_mode,
+ evt->irq = armada_370_xp_clkevt_irq;
evt->cpumask = cpumask_of(cpu);
- *__this_cpu_ptr(percpu_armada_370_xp_evt) = evt;
-
clockevents_config_and_register(evt, timer_clk, 1, 0xfffffffe);
enable_percpu_irq(evt->irq, 0);
return 0;
}
-static void armada_370_xp_timer_stop(struct clock_event_device *evt)
+static void armada_370_xp_timer_stop(struct clock_event_device *evt)
{
evt->set_mode(CLOCK_EVT_MODE_UNUSED, evt);
disable_percpu_irq(evt->irq);
}
-static struct local_timer_ops armada_370_xp_local_timer_ops __cpuinitdata = {
- .setup = armada_370_xp_timer_setup,
- .stop = armada_370_xp_timer_stop,
+static int armada_370_xp_timer_cpu_notify(struct notifier_block *self,
+ unsigned long action, void *hcpu)
+{
+ /*
+ * Grab cpu pointer in each case to avoid spurious
+ * preemptible warnings
+ */
+ switch (action & ~CPU_TASKS_FROZEN) {
+ case CPU_STARTING:
+ armada_370_xp_timer_setup(this_cpu_ptr(armada_370_xp_evt));
+ break;
+ case CPU_DYING:
+ armada_370_xp_timer_stop(this_cpu_ptr(armada_370_xp_evt));
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block armada_370_xp_timer_cpu_nb = {
+ .notifier_call = armada_370_xp_timer_cpu_notify,
};
-void __init armada_370_xp_timer_init(void)
+static void __init armada_370_xp_timer_common_init(struct device_node *np)
{
- u32 u;
- struct device_node *np;
+ u32 clr = 0, set = 0;
int res;
- np = of_find_compatible_node(NULL, NULL, "marvell,armada-370-xp-timer");
timer_base = of_iomap(np, 0);
WARN_ON(!timer_base);
local_base = of_iomap(np, 1);
- if (of_find_property(np, "marvell,timer-25Mhz", NULL)) {
- /* The fixed 25MHz timer is available so let's use it */
- u = readl(local_base + TIMER_CTRL_OFF);
- writel(u | TIMER0_25MHZ,
- local_base + TIMER_CTRL_OFF);
- u = readl(timer_base + TIMER_CTRL_OFF);
- writel(u | TIMER0_25MHZ,
- timer_base + TIMER_CTRL_OFF);
- timer_clk = 25000000;
- } else {
- unsigned long rate = 0;
- struct clk *clk = of_clk_get(np, 0);
- WARN_ON(IS_ERR(clk));
- rate = clk_get_rate(clk);
- u = readl(local_base + TIMER_CTRL_OFF);
- writel(u & ~(TIMER0_25MHZ),
- local_base + TIMER_CTRL_OFF);
-
- u = readl(timer_base + TIMER_CTRL_OFF);
- writel(u & ~(TIMER0_25MHZ),
- timer_base + TIMER_CTRL_OFF);
-
- timer_clk = rate / TIMER_DIVIDER;
- timer25Mhz = false;
- }
+ if (timer25Mhz)
+ set = TIMER0_25MHZ;
+ else
+ clr = TIMER0_25MHZ;
+ timer_ctrl_clrset(clr, set);
+ local_timer_ctrl_clrset(clr, set);
/*
* We use timer 0 as clocksource, and private(local) timer 0
* for clockevents
*/
- armada_370_xp_clkevt.irq = irq_of_parse_and_map(np, 4);
+ armada_370_xp_clkevt_irq = irq_of_parse_and_map(np, 4);
ticks_per_jiffy = (timer_clk + HZ / 2) / HZ;
writel(0xffffffff, timer_base + TIMER0_VAL_OFF);
writel(0xffffffff, timer_base + TIMER0_RELOAD_OFF);
- u = readl(timer_base + TIMER_CTRL_OFF);
-
- writel((u | TIMER0_EN | TIMER0_RELOAD_EN |
- TIMER0_DIV(TIMER_DIVIDER_SHIFT)), timer_base + TIMER_CTRL_OFF);
+ timer_ctrl_clrset(0, TIMER0_EN | TIMER0_RELOAD_EN |
+ TIMER0_DIV(TIMER_DIVIDER_SHIFT));
clocksource_mmio_init(timer_base + TIMER0_VAL_OFF,
"armada_370_xp_clocksource",
timer_clk, 300, 32, clocksource_mmio_readl_down);
- /* Register the clockevent on the private timer of CPU 0 */
- armada_370_xp_clkevt.cpumask = cpumask_of(0);
- clockevents_config_and_register(&armada_370_xp_clkevt,
- timer_clk, 1, 0xfffffffe);
+ register_cpu_notifier(&armada_370_xp_timer_cpu_nb);
- percpu_armada_370_xp_evt = alloc_percpu(struct clock_event_device *);
+ armada_370_xp_evt = alloc_percpu(struct clock_event_device);
/*
* Setup clockevent timer (interrupt-driven).
*/
- *__this_cpu_ptr(percpu_armada_370_xp_evt) = &armada_370_xp_clkevt;
- res = request_percpu_irq(armada_370_xp_clkevt.irq,
+ res = request_percpu_irq(armada_370_xp_clkevt_irq,
armada_370_xp_timer_interrupt,
- armada_370_xp_clkevt.name,
- percpu_armada_370_xp_evt);
- if (!res) {
- enable_percpu_irq(armada_370_xp_clkevt.irq, 0);
-#ifdef CONFIG_LOCAL_TIMERS
- local_timer_register(&armada_370_xp_local_timer_ops);
-#endif
- }
+ "armada_370_xp_per_cpu_tick",
+ armada_370_xp_evt);
+ /* Immediately configure the timer on the boot CPU */
+ if (!res)
+ armada_370_xp_timer_setup(this_cpu_ptr(armada_370_xp_evt));
+}
+
+static void __init armada_xp_timer_init(struct device_node *np)
+{
+ struct clk *clk = of_clk_get_by_name(np, "fixed");
+
+ /* The 25Mhz fixed clock is mandatory, and must always be available */
+ BUG_ON(IS_ERR(clk));
+ timer_clk = clk_get_rate(clk);
+
+ armada_370_xp_timer_common_init(np);
+}
+CLOCKSOURCE_OF_DECLARE(armada_xp, "marvell,armada-xp-timer",
+ armada_xp_timer_init);
+
+static void __init armada_370_timer_init(struct device_node *np)
+{
+ struct clk *clk = of_clk_get(np, 0);
+
+ BUG_ON(IS_ERR(clk));
+ timer_clk = clk_get_rate(clk) / TIMER_DIVIDER;
+ timer25Mhz = false;
+
+ armada_370_xp_timer_common_init(np);
}
+CLOCKSOURCE_OF_DECLARE(armada_370, "marvell,armada-370-timer",
+ armada_370_timer_init);
projects / ~andy / linux / blobdiff