From 3efe7a878a11c13b5297057bfc1e5639ce1241ce Mon Sep 17 00:00:00 2001 From: Tony Lindgren Date: Tue, 23 Mar 2021 09:43:25 +0200 Subject: [PATCH] clocksource/drivers/timer-ti-dm: Prepare to handle dra7 timer wrap issue There is a timer wrap issue on dra7 for the ARM architected timer. In a typical clock configuration the timer fails to wrap after 388 days. To work around the issue, we need to use timer-ti-dm timers instead. Let's prepare for adding support for percpu timers by adding a common dmtimer_clkevt_init_common() and call it from dmtimer_clockevent_init(). This patch makes no intentional functional changes. Signed-off-by: Tony Lindgren Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/20210323074326.28302-2-tony@atomide.com --- drivers/clocksource/timer-ti-dm-systimer.c | 74 ++++++++++++++-------- 1 file changed, 47 insertions(+), 27 deletions(-) diff --git a/drivers/clocksource/timer-ti-dm-systimer.c b/drivers/clocksource/timer-ti-dm-systimer.c index 186a599badb0..330803150d85 100644 --- a/drivers/clocksource/timer-ti-dm-systimer.c +++ b/drivers/clocksource/timer-ti-dm-systimer.c @@ -530,17 +530,17 @@ static void omap_clockevent_unidle(struct clock_event_device *evt) writel_relaxed(OMAP_TIMER_INT_OVERFLOW, t->base + t->wakeup); } -static int __init dmtimer_clockevent_init(struct device_node *np) +static int __init dmtimer_clkevt_init_common(struct dmtimer_clockevent *clkevt, + struct device_node *np, + unsigned int features, + const struct cpumask *cpumask, + const char *name, + int rating) { - struct dmtimer_clockevent *clkevt; struct clock_event_device *dev; struct dmtimer_systimer *t; int error; - clkevt = kzalloc(sizeof(*clkevt), GFP_KERNEL); - if (!clkevt) - return -ENOMEM; - t = &clkevt->t; dev = &clkevt->dev; @@ -548,25 +548,23 @@ static int __init dmtimer_clockevent_init(struct device_node *np) * We mostly use cpuidle_coupled with ARM local timers for runtime, * so there's probably no use for CLOCK_EVT_FEAT_DYNIRQ here. */ - dev->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; - dev->rating = 300; + dev->features = features; + dev->rating = rating; dev->set_next_event = dmtimer_set_next_event; dev->set_state_shutdown = dmtimer_clockevent_shutdown; dev->set_state_periodic = dmtimer_set_periodic; dev->set_state_oneshot = dmtimer_clockevent_shutdown; dev->set_state_oneshot_stopped = dmtimer_clockevent_shutdown; dev->tick_resume = dmtimer_clockevent_shutdown; - dev->cpumask = cpu_possible_mask; + dev->cpumask = cpumask; dev->irq = irq_of_parse_and_map(np, 0); - if (!dev->irq) { - error = -ENXIO; - goto err_out_free; - } + if (!dev->irq) + return -ENXIO; error = dmtimer_systimer_setup(np, &clkevt->t); if (error) - goto err_out_free; + return error; clkevt->period = 0xffffffff - DIV_ROUND_CLOSEST(t->rate, HZ); @@ -578,32 +576,54 @@ static int __init dmtimer_clockevent_init(struct device_node *np) writel_relaxed(OMAP_TIMER_CTRL_POSTED, t->base + t->ifctrl); error = request_irq(dev->irq, dmtimer_clockevent_interrupt, - IRQF_TIMER, "clockevent", clkevt); + IRQF_TIMER, name, clkevt); if (error) goto err_out_unmap; writel_relaxed(OMAP_TIMER_INT_OVERFLOW, t->base + t->irq_ena); writel_relaxed(OMAP_TIMER_INT_OVERFLOW, t->base + t->wakeup); - pr_info("TI gptimer clockevent: %s%lu Hz at %pOF\n", - of_find_property(np, "ti,timer-alwon", NULL) ? + pr_info("TI gptimer %s: %s%lu Hz at %pOF\n", + name, of_find_property(np, "ti,timer-alwon", NULL) ? "always-on " : "", t->rate, np->parent); - clockevents_config_and_register(dev, t->rate, - 3, /* Timer internal resync latency */ - 0xffffffff); - - if (of_machine_is_compatible("ti,am33xx") || - of_machine_is_compatible("ti,am43")) { - dev->suspend = omap_clockevent_idle; - dev->resume = omap_clockevent_unidle; - } - return 0; err_out_unmap: iounmap(t->base); + return error; +} + +static int __init dmtimer_clockevent_init(struct device_node *np) +{ + struct dmtimer_clockevent *clkevt; + int error; + + clkevt = kzalloc(sizeof(*clkevt), GFP_KERNEL); + if (!clkevt) + return -ENOMEM; + + error = dmtimer_clkevt_init_common(clkevt, np, + CLOCK_EVT_FEAT_PERIODIC | + CLOCK_EVT_FEAT_ONESHOT, + cpu_possible_mask, "clockevent", + 300); + if (error) + goto err_out_free; + + clockevents_config_and_register(&clkevt->dev, clkevt->t.rate, + 3, /* Timer internal resync latency */ + 0xffffffff); + + if (of_machine_is_compatible("ti,am33xx") || + of_machine_is_compatible("ti,am43")) { + clkevt->dev.suspend = omap_clockevent_idle; + clkevt->dev.resume = omap_clockevent_unidle; + } + + return 0; + err_out_free: kfree(clkevt);