1 files changed, 304 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-rockchip.c b/drivers/clocksource/timer-rockchip.c
new file mode 100644
index 0000000000..1f95d0aca0
--- /dev/null
+++ b/drivers/clocksource/timer-rockchip.c
@@ -0,0 +1,304 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Rockchip timer support
+ *
+ * Copyright (C) Daniel Lezcano <daniel.lezcano@linaro.org>
+ */
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/sched_clock.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define TIMER_NAME "rk_timer"
+
+#define TIMER_LOAD_COUNT0	0x00
+#define TIMER_LOAD_COUNT1	0x04
+#define TIMER_CURRENT_VALUE0	0x08
+#define TIMER_CURRENT_VALUE1	0x0C
+#define TIMER_CONTROL_REG3288	0x10
+#define TIMER_CONTROL_REG3399	0x1c
+#define TIMER_INT_STATUS	0x18
+
+#define TIMER_DISABLE		0x0
+#define TIMER_ENABLE		0x1
+#define TIMER_MODE_FREE_RUNNING			(0 << 1)
+#define TIMER_MODE_USER_DEFINED_COUNT		(1 << 1)
+#define TIMER_INT_UNMASK			(1 << 2)
+
+struct rk_timer {
+	void __iomem *base;
+	void __iomem *ctrl;
+	struct clk *clk;
+	struct clk *pclk;
+	u32 freq;
+	int irq;
+};
+
+struct rk_clkevt {
+	struct clock_event_device ce;
+	struct rk_timer timer;
+};
+
+static struct rk_clkevt *rk_clkevt;
+static struct rk_timer *rk_clksrc;
+
+static inline struct rk_timer *rk_timer(struct clock_event_device *ce)
+{
+	return &container_of(ce, struct rk_clkevt, ce)->timer;
+}
+
+static inline void rk_timer_disable(struct rk_timer *timer)
+{
+	writel_relaxed(TIMER_DISABLE, timer->ctrl);
+}
+
+static inline void rk_timer_enable(struct rk_timer *timer, u32 flags)
+{
+	writel_relaxed(TIMER_ENABLE | flags, timer->ctrl);
+}
+
+static void rk_timer_update_counter(unsigned long cycles,
+				    struct rk_timer *timer)
+{
+	writel_relaxed(cycles, timer->base + TIMER_LOAD_COUNT0);
+	writel_relaxed(0, timer->base + TIMER_LOAD_COUNT1);
+}
+
+static void rk_timer_interrupt_clear(struct rk_timer *timer)
+{
+	writel_relaxed(1, timer->base + TIMER_INT_STATUS);
+}
+
+static inline int rk_timer_set_next_event(unsigned long cycles,
+					  struct clock_event_device *ce)
+{
+	struct rk_timer *timer = rk_timer(ce);
+
+	rk_timer_disable(timer);
+	rk_timer_update_counter(cycles, timer);
+	rk_timer_enable(timer, TIMER_MODE_USER_DEFINED_COUNT |
+			       TIMER_INT_UNMASK);
+	return 0;
+}
+
+static int rk_timer_shutdown(struct clock_event_device *ce)
+{
+	struct rk_timer *timer = rk_timer(ce);
+
+	rk_timer_disable(timer);
+	return 0;
+}
+
+static int rk_timer_set_periodic(struct clock_event_device *ce)
+{
+	struct rk_timer *timer = rk_timer(ce);
+
+	rk_timer_disable(timer);
+	rk_timer_update_counter(timer->freq / HZ - 1, timer);
+	rk_timer_enable(timer, TIMER_MODE_FREE_RUNNING | TIMER_INT_UNMASK);
+	return 0;
+}
+
+static irqreturn_t rk_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *ce = dev_id;
+	struct rk_timer *timer = rk_timer(ce);
+
+	rk_timer_interrupt_clear(timer);
+
+	if (clockevent_state_oneshot(ce))
+		rk_timer_disable(timer);
+
+	ce->event_handler(ce);
+
+	return IRQ_HANDLED;
+}
+
+static u64 notrace rk_timer_sched_read(void)
+{
+	return ~readl_relaxed(rk_clksrc->base + TIMER_CURRENT_VALUE0);
+}
+
+static int __init
+rk_timer_probe(struct rk_timer *timer, struct device_node *np)
+{
+	struct clk *timer_clk;
+	struct clk *pclk;
+	int ret = -EINVAL, irq;
+	u32 ctrl_reg = TIMER_CONTROL_REG3288;
+
+	timer->base = of_iomap(np, 0);
+	if (!timer->base) {
+		pr_err("Failed to get base address for '%s'\n", TIMER_NAME);
+		return -ENXIO;
+	}
+
+	if (of_device_is_compatible(np, "rockchip,rk3399-timer"))
+		ctrl_reg = TIMER_CONTROL_REG3399;
+
+	timer->ctrl = timer->base + ctrl_reg;
+
+	pclk = of_clk_get_by_name(np, "pclk");
+	if (IS_ERR(pclk)) {
+		ret = PTR_ERR(pclk);
+		pr_err("Failed to get pclk for '%s'\n", TIMER_NAME);
+		goto out_unmap;
+	}
+
+	ret = clk_prepare_enable(pclk);
+	if (ret) {
+		pr_err("Failed to enable pclk for '%s'\n", TIMER_NAME);
+		goto out_unmap;
+	}
+	timer->pclk = pclk;
+
+	timer_clk = of_clk_get_by_name(np, "timer");
+	if (IS_ERR(timer_clk)) {
+		ret = PTR_ERR(timer_clk);
+		pr_err("Failed to get timer clock for '%s'\n", TIMER_NAME);
+		goto out_timer_clk;
+	}
+
+	ret = clk_prepare_enable(timer_clk);
+	if (ret) {
+		pr_err("Failed to enable timer clock\n");
+		goto out_timer_clk;
+	}
+	timer->clk = timer_clk;
+
+	timer->freq = clk_get_rate(timer_clk);
+
+	irq = irq_of_parse_and_map(np, 0);
+	if (!irq) {
+		ret = -EINVAL;
+		pr_err("Failed to map interrupts for '%s'\n", TIMER_NAME);
+		goto out_irq;
+	}
+	timer->irq = irq;
+
+	rk_timer_interrupt_clear(timer);
+	rk_timer_disable(timer);
+	return 0;
+
+out_irq:
+	clk_disable_unprepare(timer_clk);
+out_timer_clk:
+	clk_disable_unprepare(pclk);
+out_unmap:
+	iounmap(timer->base);
+
+	return ret;
+}
+
+static void __init rk_timer_cleanup(struct rk_timer *timer)
+{
+	clk_disable_unprepare(timer->clk);
+	clk_disable_unprepare(timer->pclk);
+	iounmap(timer->base);
+}
+
+static int __init rk_clkevt_init(struct device_node *np)
+{
+	struct clock_event_device *ce;
+	int ret = -EINVAL;
+
+	rk_clkevt = kzalloc(sizeof(struct rk_clkevt), GFP_KERNEL);
+	if (!rk_clkevt) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	ret = rk_timer_probe(&rk_clkevt->timer, np);
+	if (ret)
+		goto out_probe;
+
+	ce = &rk_clkevt->ce;
+	ce->name = TIMER_NAME;
+	ce->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT |
+		       CLOCK_EVT_FEAT_DYNIRQ;
+	ce->set_next_event = rk_timer_set_next_event;
+	ce->set_state_shutdown = rk_timer_shutdown;
+	ce->set_state_periodic = rk_timer_set_periodic;
+	ce->irq = rk_clkevt->timer.irq;
+	ce->cpumask = cpu_possible_mask;
+	ce->rating = 250;
+
+	ret = request_irq(rk_clkevt->timer.irq, rk_timer_interrupt, IRQF_TIMER,
+			  TIMER_NAME, ce);
+	if (ret) {
+		pr_err("Failed to initialize '%s': %d\n",
+			TIMER_NAME, ret);
+		goto out_irq;
+	}
+
+	clockevents_config_and_register(&rk_clkevt->ce,
+					rk_clkevt->timer.freq, 1, UINT_MAX);
+	return 0;
+
+out_irq:
+	rk_timer_cleanup(&rk_clkevt->timer);
+out_probe:
+	kfree(rk_clkevt);
+out:
+	/* Leave rk_clkevt not NULL to prevent future init */
+	rk_clkevt = ERR_PTR(ret);
+	return ret;
+}
+
+static int __init rk_clksrc_init(struct device_node *np)
+{
+	int ret = -EINVAL;
+
+	rk_clksrc = kzalloc(sizeof(struct rk_timer), GFP_KERNEL);
+	if (!rk_clksrc) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	ret = rk_timer_probe(rk_clksrc, np);
+	if (ret)
+		goto out_probe;
+
+	rk_timer_update_counter(UINT_MAX, rk_clksrc);
+	rk_timer_enable(rk_clksrc, 0);
+
+	ret = clocksource_mmio_init(rk_clksrc->base + TIMER_CURRENT_VALUE0,
+		TIMER_NAME, rk_clksrc->freq, 250, 32,
+		clocksource_mmio_readl_down);
+	if (ret) {
+		pr_err("Failed to register clocksource\n");
+		goto out_clocksource;
+	}
+
+	sched_clock_register(rk_timer_sched_read, 32, rk_clksrc->freq);
+	return 0;
+
+out_clocksource:
+	rk_timer_cleanup(rk_clksrc);
+out_probe:
+	kfree(rk_clksrc);
+out:
+	/* Leave rk_clksrc not NULL to prevent future init */
+	rk_clksrc = ERR_PTR(ret);
+	return ret;
+}
+
+static int __init rk_timer_init(struct device_node *np)
+{
+	if (!rk_clkevt)
+		return rk_clkevt_init(np);
+
+	if (!rk_clksrc)
+		return rk_clksrc_init(np);
+
+	pr_err("Too many timer definitions for '%s'\n", TIMER_NAME);
+	return -EINVAL;
+}
+
+TIMER_OF_DECLARE(rk3288_timer, "rockchip,rk3288-timer", rk_timer_init);
+TIMER_OF_DECLARE(rk3399_timer, "rockchip,rk3399-timer", rk_timer_init);