1 files changed, 390 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-sp804.c b/drivers/clocksource/timer-sp804.c
new file mode 100644
index 000000000..cd1916c05
--- /dev/null
+++ b/drivers/clocksource/timer-sp804.c
@@ -0,0 +1,390 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  linux/drivers/clocksource/timer-sp.c
+ *
+ *  Copyright (C) 1999 - 2003 ARM Limited
+ *  Copyright (C) 2000 Deep Blue Solutions Ltd
+ */
+
+#define pr_fmt(fmt)    KBUILD_MODNAME ": " fmt
+
+#include <linux/clk.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_clk.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+
+#include "timer-sp.h"
+
+/* Hisilicon 64-bit timer(a variant of ARM SP804) */
+#define HISI_TIMER_1_BASE	0x00
+#define HISI_TIMER_2_BASE	0x40
+#define HISI_TIMER_LOAD		0x00
+#define HISI_TIMER_LOAD_H	0x04
+#define HISI_TIMER_VALUE	0x08
+#define HISI_TIMER_VALUE_H	0x0c
+#define HISI_TIMER_CTRL		0x10
+#define HISI_TIMER_INTCLR	0x14
+#define HISI_TIMER_RIS		0x18
+#define HISI_TIMER_MIS		0x1c
+#define HISI_TIMER_BGLOAD	0x20
+#define HISI_TIMER_BGLOAD_H	0x24
+
+static struct sp804_timer arm_sp804_timer __initdata = {
+	.load		= TIMER_LOAD,
+	.value		= TIMER_VALUE,
+	.ctrl		= TIMER_CTRL,
+	.intclr		= TIMER_INTCLR,
+	.timer_base	= {TIMER_1_BASE, TIMER_2_BASE},
+	.width		= 32,
+};
+
+static struct sp804_timer hisi_sp804_timer __initdata = {
+	.load		= HISI_TIMER_LOAD,
+	.load_h		= HISI_TIMER_LOAD_H,
+	.value		= HISI_TIMER_VALUE,
+	.value_h	= HISI_TIMER_VALUE_H,
+	.ctrl		= HISI_TIMER_CTRL,
+	.intclr		= HISI_TIMER_INTCLR,
+	.timer_base	= {HISI_TIMER_1_BASE, HISI_TIMER_2_BASE},
+	.width		= 64,
+};
+
+static struct sp804_clkevt sp804_clkevt[NR_TIMERS];
+
+static long __init sp804_get_clock_rate(struct clk *clk, const char *name)
+{
+	int err;
+
+	if (!clk)
+		clk = clk_get_sys("sp804", name);
+	if (IS_ERR(clk)) {
+		pr_err("%s clock not found: %ld\n", name, PTR_ERR(clk));
+		return PTR_ERR(clk);
+	}
+
+	err = clk_prepare_enable(clk);
+	if (err) {
+		pr_err("clock failed to enable: %d\n", err);
+		clk_put(clk);
+		return err;
+	}
+
+	return clk_get_rate(clk);
+}
+
+static struct sp804_clkevt * __init sp804_clkevt_get(void __iomem *base)
+{
+	int i;
+
+	for (i = 0; i < NR_TIMERS; i++) {
+		if (sp804_clkevt[i].base == base)
+			return &sp804_clkevt[i];
+	}
+
+	/* It's impossible to reach here */
+	WARN_ON(1);
+
+	return NULL;
+}
+
+static struct sp804_clkevt *sched_clkevt;
+
+static u64 notrace sp804_read(void)
+{
+	return ~readl_relaxed(sched_clkevt->value);
+}
+
+static int __init sp804_clocksource_and_sched_clock_init(void __iomem *base,
+							 const char *name,
+							 struct clk *clk,
+							 int use_sched_clock)
+{
+	long rate;
+	struct sp804_clkevt *clkevt;
+
+	rate = sp804_get_clock_rate(clk, name);
+	if (rate < 0)
+		return -EINVAL;
+
+	clkevt = sp804_clkevt_get(base);
+
+	writel(0, clkevt->ctrl);
+	writel(0xffffffff, clkevt->load);
+	writel(0xffffffff, clkevt->value);
+	if (clkevt->width == 64) {
+		writel(0xffffffff, clkevt->load_h);
+		writel(0xffffffff, clkevt->value_h);
+	}
+	writel(TIMER_CTRL_32BIT | TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC,
+		clkevt->ctrl);
+
+	clocksource_mmio_init(clkevt->value, name,
+		rate, 200, 32, clocksource_mmio_readl_down);
+
+	if (use_sched_clock) {
+		sched_clkevt = clkevt;
+		sched_clock_register(sp804_read, 32, rate);
+	}
+
+	return 0;
+}
+
+
+static struct sp804_clkevt *common_clkevt;
+
+/*
+ * IRQ handler for the timer
+ */
+static irqreturn_t sp804_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	/* clear the interrupt */
+	writel(1, common_clkevt->intclr);
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static inline void evt_timer_shutdown(struct clock_event_device *evt)
+{
+	writel(0, common_clkevt->ctrl);
+}
+
+static int sp804_shutdown(struct clock_event_device *evt)
+{
+	evt_timer_shutdown(evt);
+	return 0;
+}
+
+static int sp804_set_periodic(struct clock_event_device *evt)
+{
+	unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE |
+			     TIMER_CTRL_PERIODIC | TIMER_CTRL_ENABLE;
+
+	evt_timer_shutdown(evt);
+	writel(common_clkevt->reload, common_clkevt->load);
+	writel(ctrl, common_clkevt->ctrl);
+	return 0;
+}
+
+static int sp804_set_next_event(unsigned long next,
+	struct clock_event_device *evt)
+{
+	unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE |
+			     TIMER_CTRL_ONESHOT | TIMER_CTRL_ENABLE;
+
+	writel(next, common_clkevt->load);
+	writel(ctrl, common_clkevt->ctrl);
+
+	return 0;
+}
+
+static struct clock_event_device sp804_clockevent = {
+	.features		= CLOCK_EVT_FEAT_PERIODIC |
+				  CLOCK_EVT_FEAT_ONESHOT |
+				  CLOCK_EVT_FEAT_DYNIRQ,
+	.set_state_shutdown	= sp804_shutdown,
+	.set_state_periodic	= sp804_set_periodic,
+	.set_state_oneshot	= sp804_shutdown,
+	.tick_resume		= sp804_shutdown,
+	.set_next_event		= sp804_set_next_event,
+	.rating			= 300,
+};
+
+static int __init sp804_clockevents_init(void __iomem *base, unsigned int irq,
+					 struct clk *clk, const char *name)
+{
+	struct clock_event_device *evt = &sp804_clockevent;
+	long rate;
+
+	rate = sp804_get_clock_rate(clk, name);
+	if (rate < 0)
+		return -EINVAL;
+
+	common_clkevt = sp804_clkevt_get(base);
+	common_clkevt->reload = DIV_ROUND_CLOSEST(rate, HZ);
+	evt->name = name;
+	evt->irq = irq;
+	evt->cpumask = cpu_possible_mask;
+
+	writel(0, common_clkevt->ctrl);
+
+	if (request_irq(irq, sp804_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
+			"timer", &sp804_clockevent))
+		pr_err("request_irq() failed\n");
+	clockevents_config_and_register(evt, rate, 0xf, 0xffffffff);
+
+	return 0;
+}
+
+static void __init sp804_clkevt_init(struct sp804_timer *timer, void __iomem *base)
+{
+	int i;
+
+	for (i = 0; i < NR_TIMERS; i++) {
+		void __iomem *timer_base;
+		struct sp804_clkevt *clkevt;
+
+		timer_base = base + timer->timer_base[i];
+		clkevt = &sp804_clkevt[i];
+		clkevt->base	= timer_base;
+		clkevt->load	= timer_base + timer->load;
+		clkevt->load_h	= timer_base + timer->load_h;
+		clkevt->value	= timer_base + timer->value;
+		clkevt->value_h	= timer_base + timer->value_h;
+		clkevt->ctrl	= timer_base + timer->ctrl;
+		clkevt->intclr	= timer_base + timer->intclr;
+		clkevt->width	= timer->width;
+	}
+}
+
+static int __init sp804_of_init(struct device_node *np, struct sp804_timer *timer)
+{
+	static bool initialized = false;
+	void __iomem *base;
+	void __iomem *timer1_base;
+	void __iomem *timer2_base;
+	int irq, ret = -EINVAL;
+	u32 irq_num = 0;
+	struct clk *clk1, *clk2;
+	const char *name = of_get_property(np, "compatible", NULL);
+
+	if (initialized) {
+		pr_debug("%pOF: skipping further SP804 timer device\n", np);
+		return 0;
+	}
+
+	base = of_iomap(np, 0);
+	if (!base)
+		return -ENXIO;
+
+	timer1_base = base + timer->timer_base[0];
+	timer2_base = base + timer->timer_base[1];
+
+	/* Ensure timers are disabled */
+	writel(0, timer1_base + timer->ctrl);
+	writel(0, timer2_base + timer->ctrl);
+
+	clk1 = of_clk_get(np, 0);
+	if (IS_ERR(clk1))
+		clk1 = NULL;
+
+	/* Get the 2nd clock if the timer has 3 timer clocks */
+	if (of_clk_get_parent_count(np) == 3) {
+		clk2 = of_clk_get(np, 1);
+		if (IS_ERR(clk2)) {
+			pr_err("%pOFn clock not found: %d\n", np,
+				(int)PTR_ERR(clk2));
+			clk2 = NULL;
+		}
+	} else
+		clk2 = clk1;
+
+	irq = irq_of_parse_and_map(np, 0);
+	if (irq <= 0)
+		goto err;
+
+	sp804_clkevt_init(timer, base);
+
+	of_property_read_u32(np, "arm,sp804-has-irq", &irq_num);
+	if (irq_num == 2) {
+
+		ret = sp804_clockevents_init(timer2_base, irq, clk2, name);
+		if (ret)
+			goto err;
+
+		ret = sp804_clocksource_and_sched_clock_init(timer1_base,
+							     name, clk1, 1);
+		if (ret)
+			goto err;
+	} else {
+
+		ret = sp804_clockevents_init(timer1_base, irq, clk1, name);
+		if (ret)
+			goto err;
+
+		ret = sp804_clocksource_and_sched_clock_init(timer2_base,
+							     name, clk2, 1);
+		if (ret)
+			goto err;
+	}
+	initialized = true;
+
+	return 0;
+err:
+	iounmap(base);
+	return ret;
+}
+
+static int __init arm_sp804_of_init(struct device_node *np)
+{
+	return sp804_of_init(np, &arm_sp804_timer);
+}
+TIMER_OF_DECLARE(sp804, "arm,sp804", arm_sp804_of_init);
+
+static int __init hisi_sp804_of_init(struct device_node *np)
+{
+	return sp804_of_init(np, &hisi_sp804_timer);
+}
+TIMER_OF_DECLARE(hisi_sp804, "hisilicon,sp804", hisi_sp804_of_init);
+
+static int __init integrator_cp_of_init(struct device_node *np)
+{
+	static int init_count = 0;
+	void __iomem *base;
+	int irq, ret = -EINVAL;
+	const char *name = of_get_property(np, "compatible", NULL);
+	struct clk *clk;
+
+	base = of_iomap(np, 0);
+	if (!base) {
+		pr_err("Failed to iomap\n");
+		return -ENXIO;
+	}
+
+	clk = of_clk_get(np, 0);
+	if (IS_ERR(clk)) {
+		pr_err("Failed to get clock\n");
+		return PTR_ERR(clk);
+	}
+
+	/* Ensure timer is disabled */
+	writel(0, base + arm_sp804_timer.ctrl);
+
+	if (init_count == 2 || !of_device_is_available(np))
+		goto err;
+
+	sp804_clkevt_init(&arm_sp804_timer, base);
+
+	if (!init_count) {
+		ret = sp804_clocksource_and_sched_clock_init(base,
+							     name, clk, 0);
+		if (ret)
+			goto err;
+	} else {
+		irq = irq_of_parse_and_map(np, 0);
+		if (irq <= 0)
+			goto err;
+
+		ret = sp804_clockevents_init(base, irq, clk, name);
+		if (ret)
+			goto err;
+	}
+
+	init_count++;
+	return 0;
+err:
+	iounmap(base);
+	return ret;
+}
+TIMER_OF_DECLARE(intcp, "arm,integrator-cp-timer", integrator_cp_of_init);