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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/clocksource/timer-sun5i.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/clocksource/timer-sun5i.c')
-rw-r--r--drivers/clocksource/timer-sun5i.c330
1 files changed, 330 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-sun5i.c b/drivers/clocksource/timer-sun5i.c
new file mode 100644
index 0000000000..69fee3540d
--- /dev/null
+++ b/drivers/clocksource/timer-sun5i.c
@@ -0,0 +1,330 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Allwinner SoCs hstimer driver.
+ *
+ * Copyright (C) 2013 Maxime Ripard
+ *
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqreturn.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+
+#define TIMER_IRQ_EN_REG 0x00
+#define TIMER_IRQ_EN(val) BIT(val)
+#define TIMER_IRQ_ST_REG 0x04
+#define TIMER_CTL_REG(val) (0x20 * (val) + 0x10)
+#define TIMER_CTL_ENABLE BIT(0)
+#define TIMER_CTL_RELOAD BIT(1)
+#define TIMER_CTL_CLK_PRES(val) (((val) & 0x7) << 4)
+#define TIMER_CTL_ONESHOT BIT(7)
+#define TIMER_INTVAL_LO_REG(val) (0x20 * (val) + 0x14)
+#define TIMER_INTVAL_HI_REG(val) (0x20 * (val) + 0x18)
+#define TIMER_CNTVAL_LO_REG(val) (0x20 * (val) + 0x1c)
+#define TIMER_CNTVAL_HI_REG(val) (0x20 * (val) + 0x20)
+
+#define TIMER_SYNC_TICKS 3
+
+struct sun5i_timer {
+ void __iomem *base;
+ struct clk *clk;
+ struct notifier_block clk_rate_cb;
+ u32 ticks_per_jiffy;
+ struct clocksource clksrc;
+ struct clock_event_device clkevt;
+};
+
+#define nb_to_sun5i_timer(x) \
+ container_of(x, struct sun5i_timer, clk_rate_cb)
+#define clksrc_to_sun5i_timer(x) \
+ container_of(x, struct sun5i_timer, clksrc)
+#define clkevt_to_sun5i_timer(x) \
+ container_of(x, struct sun5i_timer, clkevt)
+
+/*
+ * When we disable a timer, we need to wait at least for 2 cycles of
+ * the timer source clock. We will use for that the clocksource timer
+ * that is already setup and runs at the same frequency than the other
+ * timers, and we never will be disabled.
+ */
+static void sun5i_clkevt_sync(struct sun5i_timer *ce)
+{
+ u32 old = readl(ce->base + TIMER_CNTVAL_LO_REG(1));
+
+ while ((old - readl(ce->base + TIMER_CNTVAL_LO_REG(1))) < TIMER_SYNC_TICKS)
+ cpu_relax();
+}
+
+static void sun5i_clkevt_time_stop(struct sun5i_timer *ce, u8 timer)
+{
+ u32 val = readl(ce->base + TIMER_CTL_REG(timer));
+ writel(val & ~TIMER_CTL_ENABLE, ce->base + TIMER_CTL_REG(timer));
+
+ sun5i_clkevt_sync(ce);
+}
+
+static void sun5i_clkevt_time_setup(struct sun5i_timer *ce, u8 timer, u32 delay)
+{
+ writel(delay, ce->base + TIMER_INTVAL_LO_REG(timer));
+}
+
+static void sun5i_clkevt_time_start(struct sun5i_timer *ce, u8 timer, bool periodic)
+{
+ u32 val = readl(ce->base + TIMER_CTL_REG(timer));
+
+ if (periodic)
+ val &= ~TIMER_CTL_ONESHOT;
+ else
+ val |= TIMER_CTL_ONESHOT;
+
+ writel(val | TIMER_CTL_ENABLE | TIMER_CTL_RELOAD,
+ ce->base + TIMER_CTL_REG(timer));
+}
+
+static int sun5i_clkevt_shutdown(struct clock_event_device *clkevt)
+{
+ struct sun5i_timer *ce = clkevt_to_sun5i_timer(clkevt);
+
+ sun5i_clkevt_time_stop(ce, 0);
+ return 0;
+}
+
+static int sun5i_clkevt_set_oneshot(struct clock_event_device *clkevt)
+{
+ struct sun5i_timer *ce = clkevt_to_sun5i_timer(clkevt);
+
+ sun5i_clkevt_time_stop(ce, 0);
+ sun5i_clkevt_time_start(ce, 0, false);
+ return 0;
+}
+
+static int sun5i_clkevt_set_periodic(struct clock_event_device *clkevt)
+{
+ struct sun5i_timer *ce = clkevt_to_sun5i_timer(clkevt);
+
+ sun5i_clkevt_time_stop(ce, 0);
+ sun5i_clkevt_time_setup(ce, 0, ce->ticks_per_jiffy);
+ sun5i_clkevt_time_start(ce, 0, true);
+ return 0;
+}
+
+static int sun5i_clkevt_next_event(unsigned long evt,
+ struct clock_event_device *clkevt)
+{
+ struct sun5i_timer *ce = clkevt_to_sun5i_timer(clkevt);
+
+ sun5i_clkevt_time_stop(ce, 0);
+ sun5i_clkevt_time_setup(ce, 0, evt - TIMER_SYNC_TICKS);
+ sun5i_clkevt_time_start(ce, 0, false);
+
+ return 0;
+}
+
+static irqreturn_t sun5i_timer_interrupt(int irq, void *dev_id)
+{
+ struct sun5i_timer *ce = dev_id;
+
+ writel(0x1, ce->base + TIMER_IRQ_ST_REG);
+ ce->clkevt.event_handler(&ce->clkevt);
+
+ return IRQ_HANDLED;
+}
+
+static u64 sun5i_clksrc_read(struct clocksource *clksrc)
+{
+ struct sun5i_timer *cs = clksrc_to_sun5i_timer(clksrc);
+
+ return ~readl(cs->base + TIMER_CNTVAL_LO_REG(1));
+}
+
+static int sun5i_rate_cb(struct notifier_block *nb,
+ unsigned long event, void *data)
+{
+ struct clk_notifier_data *ndata = data;
+ struct sun5i_timer *cs = nb_to_sun5i_timer(nb);
+
+ switch (event) {
+ case PRE_RATE_CHANGE:
+ clocksource_unregister(&cs->clksrc);
+ break;
+
+ case POST_RATE_CHANGE:
+ clocksource_register_hz(&cs->clksrc, ndata->new_rate);
+ clockevents_update_freq(&cs->clkevt, ndata->new_rate);
+ cs->ticks_per_jiffy = DIV_ROUND_UP(ndata->new_rate, HZ);
+ break;
+
+ default:
+ break;
+ }
+
+ return NOTIFY_DONE;
+}
+
+static int sun5i_setup_clocksource(struct platform_device *pdev,
+ unsigned long rate)
+{
+ struct sun5i_timer *cs = platform_get_drvdata(pdev);
+ void __iomem *base = cs->base;
+ int ret;
+
+ writel(~0, base + TIMER_INTVAL_LO_REG(1));
+ writel(TIMER_CTL_ENABLE | TIMER_CTL_RELOAD,
+ base + TIMER_CTL_REG(1));
+
+ cs->clksrc.name = pdev->dev.of_node->name;
+ cs->clksrc.rating = 340;
+ cs->clksrc.read = sun5i_clksrc_read;
+ cs->clksrc.mask = CLOCKSOURCE_MASK(32);
+ cs->clksrc.flags = CLOCK_SOURCE_IS_CONTINUOUS;
+
+ ret = clocksource_register_hz(&cs->clksrc, rate);
+ if (ret) {
+ dev_err(&pdev->dev, "Couldn't register clock source.\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int sun5i_setup_clockevent(struct platform_device *pdev,
+ unsigned long rate, int irq)
+{
+ struct device *dev = &pdev->dev;
+ struct sun5i_timer *ce = platform_get_drvdata(pdev);
+ void __iomem *base = ce->base;
+ int ret;
+ u32 val;
+
+ ce->clkevt.name = dev->of_node->name;
+ ce->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
+ ce->clkevt.set_next_event = sun5i_clkevt_next_event;
+ ce->clkevt.set_state_shutdown = sun5i_clkevt_shutdown;
+ ce->clkevt.set_state_periodic = sun5i_clkevt_set_periodic;
+ ce->clkevt.set_state_oneshot = sun5i_clkevt_set_oneshot;
+ ce->clkevt.tick_resume = sun5i_clkevt_shutdown;
+ ce->clkevt.rating = 340;
+ ce->clkevt.irq = irq;
+ ce->clkevt.cpumask = cpu_possible_mask;
+
+ /* Enable timer0 interrupt */
+ val = readl(base + TIMER_IRQ_EN_REG);
+ writel(val | TIMER_IRQ_EN(0), base + TIMER_IRQ_EN_REG);
+
+ clockevents_config_and_register(&ce->clkevt, rate,
+ TIMER_SYNC_TICKS, 0xffffffff);
+
+ ret = devm_request_irq(dev, irq, sun5i_timer_interrupt,
+ IRQF_TIMER | IRQF_IRQPOLL,
+ "sun5i_timer0", ce);
+ if (ret) {
+ dev_err(dev, "Unable to register interrupt\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int sun5i_timer_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct sun5i_timer *st;
+ struct reset_control *rstc;
+ void __iomem *timer_base;
+ struct clk *clk;
+ unsigned long rate;
+ int irq, ret;
+
+ st = devm_kzalloc(dev, sizeof(*st), GFP_KERNEL);
+ if (!st)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, st);
+
+ timer_base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(timer_base)) {
+ dev_err(dev, "Can't map registers\n");
+ return PTR_ERR(timer_base);
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(dev, "Can't get IRQ\n");
+ return irq;
+ }
+
+ clk = devm_clk_get_enabled(dev, NULL);
+ if (IS_ERR(clk)) {
+ dev_err(dev, "Can't get timer clock\n");
+ return PTR_ERR(clk);
+ }
+
+ rate = clk_get_rate(clk);
+ if (!rate) {
+ dev_err(dev, "Couldn't get parent clock rate\n");
+ return -EINVAL;
+ }
+
+ st->base = timer_base;
+ st->ticks_per_jiffy = DIV_ROUND_UP(rate, HZ);
+ st->clk = clk;
+ st->clk_rate_cb.notifier_call = sun5i_rate_cb;
+ st->clk_rate_cb.next = NULL;
+
+ ret = devm_clk_notifier_register(dev, clk, &st->clk_rate_cb);
+ if (ret) {
+ dev_err(dev, "Unable to register clock notifier.\n");
+ return ret;
+ }
+
+ rstc = devm_reset_control_get_optional_exclusive(dev, NULL);
+ if (rstc)
+ reset_control_deassert(rstc);
+
+ ret = sun5i_setup_clocksource(pdev, rate);
+ if (ret)
+ return ret;
+
+ ret = sun5i_setup_clockevent(pdev, rate, irq);
+ if (ret)
+ goto err_unreg_clocksource;
+
+ return 0;
+
+err_unreg_clocksource:
+ clocksource_unregister(&st->clksrc);
+ return ret;
+}
+
+static void sun5i_timer_remove(struct platform_device *pdev)
+{
+ struct sun5i_timer *st = platform_get_drvdata(pdev);
+
+ clocksource_unregister(&st->clksrc);
+}
+
+static const struct of_device_id sun5i_timer_of_match[] = {
+ { .compatible = "allwinner,sun5i-a13-hstimer" },
+ { .compatible = "allwinner,sun7i-a20-hstimer" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, sun5i_timer_of_match);
+
+static struct platform_driver sun5i_timer_driver = {
+ .probe = sun5i_timer_probe,
+ .remove_new = sun5i_timer_remove,
+ .driver = {
+ .name = "sun5i-timer",
+ .of_match_table = sun5i_timer_of_match,
+ .suppress_bind_attrs = true,
+ },
+};
+module_platform_driver(sun5i_timer_driver);