From: Markus Schneider-Pargmann (TI) Date: Fri, 8 May 2026 13:39:29 +0000 (+0200) Subject: clocksource/drivers/timer-ti-dm: Add clockevent support X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=e393cca0388c2fe6f67d4658b2e05f57e244285b;p=thirdparty%2Fkernel%2Flinux.git clocksource/drivers/timer-ti-dm: Add clockevent support Add support for using the TI Dual-Mode Timer for clockevents. The second always on device with the "ti,timer-alwon" property is selected to be used for clockevents. The first one is used as clocksource. This allows clockevents to be setup independently of the CPU. Signed-off-by: Markus Schneider-Pargmann (TI) Signed-off-by: Daniel Lezcano Link: https://patch.msgid.link/20260508-topic-ti-dm-clkevt-v6-16-v5-3-61d546a0aff9@baylibre.com --- diff --git a/drivers/clocksource/timer-ti-dm.c b/drivers/clocksource/timer-ti-dm.c index 98cc343087689..bd06afb7d5226 100644 --- a/drivers/clocksource/timer-ti-dm.c +++ b/drivers/clocksource/timer-ti-dm.c @@ -21,8 +21,10 @@ #include #include #include +#include #include #include +#include #include #include #include @@ -156,6 +158,13 @@ struct dmtimer_clocksource { unsigned int loadval; }; +struct omap_dm_timer_clockevent { + struct clock_event_device dev; + struct dmtimer *timer; + u32 period; +}; + +static bool omap_dm_timer_clockevent_setup; static void __iomem *omap_dm_timer_sched_clock_counter; enum { @@ -1281,6 +1290,106 @@ static int omap_dm_timer_setup_clocksource(struct dmtimer *timer) return 0; } +static struct omap_dm_timer_clockevent *to_dm_timer_clockevent(struct clock_event_device *evt) +{ + return container_of(evt, struct omap_dm_timer_clockevent, dev); +} + +static int omap_dm_timer_evt_set_next_event(unsigned long cycles, + struct clock_event_device *evt) +{ + struct omap_dm_timer_clockevent *clkevt = to_dm_timer_clockevent(evt); + struct dmtimer *timer = clkevt->timer; + + dmtimer_write(timer, OMAP_TIMER_COUNTER_REG, 0xffffffff - cycles); + dmtimer_write(timer, OMAP_TIMER_CTRL_REG, OMAP_TIMER_CTRL_ST); + + return 0; +} + +static int omap_dm_timer_evt_shutdown(struct clock_event_device *evt) +{ + struct omap_dm_timer_clockevent *clkevt = to_dm_timer_clockevent(evt); + struct dmtimer *timer = clkevt->timer; + + __omap_dm_timer_stop(timer); + + return 0; +} + +static int omap_dm_timer_evt_set_periodic(struct clock_event_device *evt) +{ + struct omap_dm_timer_clockevent *clkevt = to_dm_timer_clockevent(evt); + struct dmtimer *timer = clkevt->timer; + + omap_dm_timer_evt_shutdown(evt); + + omap_dm_timer_set_load(&timer->cookie, clkevt->period); + dmtimer_write(timer, OMAP_TIMER_COUNTER_REG, clkevt->period); + dmtimer_write(timer, OMAP_TIMER_CTRL_REG, + OMAP_TIMER_CTRL_AR | OMAP_TIMER_CTRL_ST); + + return 0; +} + +static irqreturn_t omap_dm_timer_evt_interrupt(int irq, void *dev_id) +{ + struct omap_dm_timer_clockevent *clkevt = dev_id; + struct dmtimer *timer = clkevt->timer; + + __omap_dm_timer_write_status(timer, OMAP_TIMER_INT_OVERFLOW); + + clkevt->dev.event_handler(&clkevt->dev); + + return IRQ_HANDLED; +} + +static int omap_dm_timer_setup_clockevent(struct dmtimer *timer) +{ + struct device *dev = &timer->pdev->dev; + struct omap_dm_timer_clockevent *clkevt; + int ret; + + clkevt = devm_kzalloc(dev, sizeof(*clkevt), GFP_KERNEL); + if (!clkevt) + return -ENOMEM; + + timer->reserved = 1; + clkevt->timer = timer; + + clkevt->dev.name = "omap_dm_timer"; + clkevt->dev.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; + clkevt->dev.rating = 300; + clkevt->dev.set_next_event = omap_dm_timer_evt_set_next_event; + clkevt->dev.set_state_shutdown = omap_dm_timer_evt_shutdown; + clkevt->dev.set_state_periodic = omap_dm_timer_evt_set_periodic; + clkevt->dev.set_state_oneshot = omap_dm_timer_evt_shutdown; + clkevt->dev.set_state_oneshot_stopped = omap_dm_timer_evt_shutdown; + clkevt->dev.tick_resume = omap_dm_timer_evt_shutdown; + clkevt->dev.cpumask = cpu_possible_mask; + clkevt->period = 0xffffffff - DIV_ROUND_CLOSEST(timer->fclk_rate, HZ); + + __omap_dm_timer_init_regs(timer); + __omap_dm_timer_stop(timer); + __omap_dm_timer_enable_posted(timer); + + ret = devm_request_irq(dev, timer->irq, omap_dm_timer_evt_interrupt, + IRQF_TIMER, "omap_dm_timer_clockevent", clkevt); + if (ret) { + dev_err(dev, "Failed to request interrupt: %d\n", ret); + return ret; + } + + __omap_dm_timer_int_enable(timer, OMAP_TIMER_INT_OVERFLOW); + + clockevents_config_and_register(&clkevt->dev, timer->fclk_rate, + 3, + 0xffffffff); + + omap_dm_timer_clockevent_setup = true; + return 0; +} + /** * omap_dm_timer_probe - probe function called for every registered device * @pdev: pointer to current timer platform device @@ -1368,11 +1477,16 @@ static int omap_dm_timer_probe(struct platform_device *pdev) timer->pdev = pdev; - if (timer->capability & OMAP_TIMER_ALWON && !IS_ERR_OR_NULL(timer->fclk) && - !omap_dm_timer_sched_clock_counter) { - ret = omap_dm_timer_setup_clocksource(timer); - if (ret) - return ret; + if (timer->capability & OMAP_TIMER_ALWON && !IS_ERR_OR_NULL(timer->fclk)) { + if (!omap_dm_timer_sched_clock_counter) { + ret = omap_dm_timer_setup_clocksource(timer); + if (ret) + return ret; + } else if (!omap_dm_timer_clockevent_setup) { + ret = omap_dm_timer_setup_clockevent(timer); + if (ret) + return ret; + } } pm_runtime_enable(dev);