1 files changed, 179 insertions, 0 deletions
diff --git a/arch/arm/mach-iop32x/time.c b/arch/arm/mach-iop32x/time.c
new file mode 100644
index 000000000..ae533b66f
--- /dev/null
+++ b/arch/arm/mach-iop32x/time.c
@@ -0,0 +1,179 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * arch/arm/plat-iop/time.c
+ *
+ * Timer code for IOP32x and IOP33x based systems
+ *
+ * Author: Deepak Saxena <dsaxena@mvista.com>
+ *
+ * Copyright 2002-2003 MontaVista Software Inc.
+ */
+
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/time.h>
+#include <linux/init.h>
+#include <linux/timex.h>
+#include <linux/io.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/export.h>
+#include <linux/sched_clock.h>
+#include <asm/irq.h>
+#include <linux/uaccess.h>
+#include <asm/mach/irq.h>
+#include <asm/mach/time.h>
+
+#include "hardware.h"
+#include "irqs.h"
+
+/*
+ * Minimum clocksource/clockevent timer range in seconds
+ */
+#define IOP_MIN_RANGE 4
+
+/*
+ * IOP clocksource (free-running timer 1).
+ */
+static u64 notrace iop_clocksource_read(struct clocksource *unused)
+{
+	return 0xffffffffu - read_tcr1();
+}
+
+static struct clocksource iop_clocksource = {
+	.name 		= "iop_timer1",
+	.rating		= 300,
+	.read		= iop_clocksource_read,
+	.mask		= CLOCKSOURCE_MASK(32),
+	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+/*
+ * IOP sched_clock() implementation via its clocksource.
+ */
+static u64 notrace iop_read_sched_clock(void)
+{
+	return 0xffffffffu - read_tcr1();
+}
+
+/*
+ * IOP clockevents (interrupting timer 0).
+ */
+static int iop_set_next_event(unsigned long delta,
+			      struct clock_event_device *unused)
+{
+	u32 tmr = IOP_TMR_PRIVILEGED | IOP_TMR_RATIO_1_1;
+
+	BUG_ON(delta == 0);
+	write_tmr0(tmr & ~(IOP_TMR_EN | IOP_TMR_RELOAD));
+	write_tcr0(delta);
+	write_tmr0((tmr & ~IOP_TMR_RELOAD) | IOP_TMR_EN);
+
+	return 0;
+}
+
+static unsigned long ticks_per_jiffy;
+
+static int iop_set_periodic(struct clock_event_device *evt)
+{
+	u32 tmr = read_tmr0();
+
+	write_tmr0(tmr & ~IOP_TMR_EN);
+	write_tcr0(ticks_per_jiffy - 1);
+	write_trr0(ticks_per_jiffy - 1);
+	tmr |= (IOP_TMR_RELOAD | IOP_TMR_EN);
+
+	write_tmr0(tmr);
+	return 0;
+}
+
+static int iop_set_oneshot(struct clock_event_device *evt)
+{
+	u32 tmr = read_tmr0();
+
+	/* ->set_next_event sets period and enables timer */
+	tmr &= ~(IOP_TMR_RELOAD | IOP_TMR_EN);
+	write_tmr0(tmr);
+	return 0;
+}
+
+static int iop_shutdown(struct clock_event_device *evt)
+{
+	u32 tmr = read_tmr0();
+
+	tmr &= ~IOP_TMR_EN;
+	write_tmr0(tmr);
+	return 0;
+}
+
+static int iop_resume(struct clock_event_device *evt)
+{
+	u32 tmr = read_tmr0();
+
+	tmr |= IOP_TMR_EN;
+	write_tmr0(tmr);
+	return 0;
+}
+
+static struct clock_event_device iop_clockevent = {
+	.name			= "iop_timer0",
+	.features		= CLOCK_EVT_FEAT_PERIODIC |
+				  CLOCK_EVT_FEAT_ONESHOT,
+	.rating			= 300,
+	.set_next_event		= iop_set_next_event,
+	.set_state_shutdown	= iop_shutdown,
+	.set_state_periodic	= iop_set_periodic,
+	.tick_resume		= iop_resume,
+	.set_state_oneshot	= iop_set_oneshot,
+};
+
+static irqreturn_t
+iop_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	write_tisr(1);
+	evt->event_handler(evt);
+	return IRQ_HANDLED;
+}
+
+static unsigned long iop_tick_rate;
+unsigned long get_iop_tick_rate(void)
+{
+	return iop_tick_rate;
+}
+EXPORT_SYMBOL(get_iop_tick_rate);
+
+void __init iop_init_time(unsigned long tick_rate)
+{
+	u32 timer_ctl;
+	int irq = IRQ_IOP32X_TIMER0;
+
+	sched_clock_register(iop_read_sched_clock, 32, tick_rate);
+
+	ticks_per_jiffy = DIV_ROUND_CLOSEST(tick_rate, HZ);
+	iop_tick_rate = tick_rate;
+
+	timer_ctl = IOP_TMR_EN | IOP_TMR_PRIVILEGED |
+			IOP_TMR_RELOAD | IOP_TMR_RATIO_1_1;
+
+	/*
+	 * Set up interrupting clockevent timer 0.
+	 */
+	write_tmr0(timer_ctl & ~IOP_TMR_EN);
+	write_tisr(1);
+	if (request_irq(irq, iop_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
+			"IOP Timer Tick", &iop_clockevent))
+		pr_err("Failed to request irq() %d (IOP Timer Tick)\n", irq);
+	iop_clockevent.cpumask = cpumask_of(0);
+	clockevents_config_and_register(&iop_clockevent, tick_rate,
+					0xf, 0xfffffffe);
+
+	/*
+	 * Set up free-running clocksource timer 1.
+	 */
+	write_trr1(0xffffffff);
+	write_tcr1(0xffffffff);
+	write_tmr1(timer_ctl);
+	clocksource_register_hz(&iop_clocksource, tick_rate);
+}