@@ -18,6 +18,7 @@ obj-$(CONFIG_CLKSRC_MMIO) += mmio.o
obj-$(CONFIG_DAVINCI_TIMER) += timer-davinci.o
obj-$(CONFIG_DIGICOLOR_TIMER) += timer-digicolor.o
obj-$(CONFIG_OMAP_DM_TIMER) += timer-ti-dm.o
+obj-$(CONFIG_OMAP_DM_TIMER) += timer-ti-dm-systimer.o
obj-$(CONFIG_DW_APB_TIMER) += dw_apb_timer.o
obj-$(CONFIG_DW_APB_TIMER_OF) += dw_apb_timer_of.o
obj-$(CONFIG_FTTMR010_TIMER) += timer-fttmr010.o
new file mode 100644
@@ -0,0 +1,731 @@
+// SPDX-License-Identifier: GPL-2.0+
+#include <linux/clk.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+
+#include <linux/clk/clk-conf.h>
+
+#include <clocksource/timer-ti-dm.h>
+#include <dt-bindings/bus/ti-sysc.h>
+
+/* For type1, set SYSC_OMAP2_CLOCKACTIVITY for fck off on idle, l4 clock on */
+#define DMTIMER_TYPE1_ENABLE ((1 << 9) | (SYSC_IDLE_SMART << 3) | \
+ SYSC_OMAP2_ENAWAKEUP | SYSC_OMAP2_AUTOIDLE)
+
+#define DMTIMER_TYPE2_ENABLE (SYSC_IDLE_SMART_WKUP << 2)
+#define DMTIMER_RESET_WAIT 100000
+
+#define DMTIMER_INST_DONT_CARE ~0U
+
+static int counter_32k;
+static u32 clocksource;
+static u32 clockevent;
+
+/*
+ * Subset of the timer registers we use. Note that the register offsets
+ * depend on the timer revision detected.
+ */
+struct dmtimer_systimer {
+ void __iomem *base;
+ u8 sysc;
+ u8 irq_stat;
+ u8 irq_ena;
+ u8 pend;
+ u8 load;
+ u8 counter;
+ u8 ctrl;
+ u8 wakeup;
+ u8 ifctrl;
+ unsigned long rate;
+};
+
+struct dmtimer_clockevent {
+ struct clock_event_device dev;
+ struct dmtimer_systimer t;
+ u32 period;
+};
+
+struct dmtimer_clocksource {
+ struct clocksource dev;
+ struct dmtimer_systimer t;
+ unsigned int loadval;
+};
+
+/* Assumes v1 ip if bits [31:16] are zero */
+static bool dmtimer_systimer_revision1(struct dmtimer_systimer *t)
+{
+ u32 tidr = readl_relaxed(t->base);
+
+ return !(tidr >> 16);
+}
+
+static int __init dmtimer_systimer_type1_reset(struct dmtimer_systimer *t)
+{
+ void __iomem *syss = t->base + OMAP_TIMER_V1_SYS_STAT_OFFSET;
+ int ret;
+ u32 l;
+
+ writel_relaxed(BIT(1) | BIT(2), t->base + t->ifctrl);
+ ret = readl_poll_timeout_atomic(syss, l, l & BIT(0), 100,
+ DMTIMER_RESET_WAIT);
+
+ return ret;
+}
+
+/* Note we must use io_base instead of func_base for type2 OCP regs */
+static int __init dmtimer_systimer_type2_reset(struct dmtimer_systimer *t)
+{
+ void __iomem *sysc = t->base + t->sysc;
+ u32 l;
+
+ l = readl_relaxed(sysc);
+ l |= BIT(0);
+ writel_relaxed(l, sysc);
+
+ return readl_poll_timeout_atomic(sysc, l, !(l & BIT(0)), 100,
+ DMTIMER_RESET_WAIT);
+}
+
+static int __init dmtimer_systimer_reset(struct dmtimer_systimer *t)
+{
+ int ret;
+
+ if (dmtimer_systimer_revision1(t))
+ ret = dmtimer_systimer_type1_reset(t);
+ else
+ ret = dmtimer_systimer_type2_reset(t);
+ if (ret < 0) {
+ pr_err("%s failed with %i\n", __func__, ret);
+
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id counter_match_table[] = {
+ { .compatible = "ti,omap-counter32k" },
+ { /* Sentinel */ },
+};
+
+/*
+ * Check if the SoC als has a usable working 32 KiHz counter. The 32 KiHz
+ * counter is handled by timer-ti-32k, but we need to detect it as it
+ * affects the preferred dmtimer system timer configuration. There is
+ * typically no use for a dmtimer clocksource if the 32 KiHz counter is
+ * present, except on am437x as described below.
+ */
+static void __init dmtimer_systimer_check_counter32k(void)
+{
+ struct device_node *np;
+
+ if (counter_32k)
+ return;
+
+ np = of_find_matching_node(NULL, counter_match_table);
+ if (!np) {
+ counter_32k = -ENODEV;
+
+ return;
+ }
+
+ if (of_device_is_available(np))
+ counter_32k = 1;
+ else
+ counter_32k = -ENODEV;
+
+ of_node_put(np);
+}
+
+static const struct of_device_id dmtimer_match_table[] = {
+ { .compatible = "ti,omap2420-timer", },
+ { .compatible = "ti,omap3430-timer", },
+ { .compatible = "ti,omap4430-timer", },
+ { .compatible = "ti,omap5430-timer", },
+ { .compatible = "ti,am335x-timer", },
+ { .compatible = "ti,am335x-timer-1ms", },
+ { .compatible = "ti,dm814-timer", },
+ { .compatible = "ti,dm816-timer", },
+ { /* Sentinel */ },
+};
+
+/*
+ * Checks that system timers are configured to not reset and idle during
+ * the generic timer-ti-dm device driver probe. And that the system timer
+ * source clocks are properly configured. Also, let's not hog any DSP and
+ * PWM capable timers unnecessarily as system timers.
+ */
+static bool __init dmtimer_is_preferred(struct device_node *np)
+{
+ if (!of_device_is_available(np))
+ return false;
+
+ if (!of_property_read_bool(np->parent,
+ "ti,no-reset-on-init"))
+ return false;
+
+ if (!of_property_read_bool(np->parent, "ti,no-idle"))
+ return false;
+
+ /* Secure gptimer12 is always clocked with a fixed source */
+ if (!of_property_read_bool(np, "ti,timer-secure")) {
+ if (!of_property_read_bool(np, "assigned-clocks"))
+ return false;
+
+ if (!of_property_read_bool(np, "assigned-clock-parents"))
+ return false;
+ }
+
+ if (of_property_read_bool(np, "ti,timer-dsp"))
+ return false;
+
+ if (of_property_read_bool(np, "ti,timer-pwm"))
+ return false;
+
+ return true;
+}
+
+/*
+ * Finds the first available usable always-on timer, and assigns it to either
+ * clockevent or clocksource depending if the counter_32k is available on the
+ * SoC or not.
+ *
+ * Some omap3 boards with unreliable oscillator must not use the counter_32k
+ * or dmtimer1 with 32 KiHz source. Additionally, the boards with unreliable
+ * oscillator should really set counter_32k as disabled, and delete dmtimer1
+ * ti,always-on property, but let's not count on it. For these quirky cases,
+ * we prefer using the always-on secure dmtimer12 with the internal 32 KiHz
+ * clock as the clocksource, and any available dmtimer as clockevent.
+ *
+ * For am437x, we are using am335x style dmtimer clocksource. It is unclear
+ * if this quirk handling is really needed, but let's change it separately
+ * based on testing as it might cause side effects.
+ */
+static void __init dmtimer_systimer_assign_alwon(void)
+{
+ struct device_node *np;
+ u32 pa = 0;
+ bool quirk_unreliable_oscillator = false;
+
+ /* Quirk unreliable 32 KiHz oscillator with incomplete dts */
+ if (of_machine_is_compatible("ti,omap3-beagle") ||
+ of_machine_is_compatible("timll,omap3-devkit8000")) {
+ quirk_unreliable_oscillator = true;
+ counter_32k = -ENODEV;
+ }
+
+ /* Quirk am437x using am335x style dmtimer clocksource */
+ if (of_machine_is_compatible("ti,am43"))
+ counter_32k = -ENODEV;
+
+ for_each_matching_node(np, dmtimer_match_table) {
+ if (!dmtimer_is_preferred(np))
+ continue;
+
+ if (of_property_read_bool(np, "ti,timer-alwon")) {
+ const __be32 *addr;
+
+ addr = of_get_address(np, 0, NULL, NULL);
+ pa = of_translate_address(np, addr);
+ if (pa) {
+ /* Quirky omap3 boards must use dmtimer12 */
+ if (quirk_unreliable_oscillator &&
+ pa == 0x48318000)
+ continue;
+
+ of_node_put(np);
+ break;
+ }
+ }
+ }
+
+ /* Usually no need for dmtimer clocksource if we have counter32 */
+ if (counter_32k >= 0) {
+ clockevent = pa;
+ clocksource = 0;
+ } else {
+ clocksource = pa;
+ clockevent = DMTIMER_INST_DONT_CARE;
+ }
+}
+
+/* Finds the first usable dmtimer, used for the don't care case */
+static u32 __init dmtimer_systimer_find_first_available(void)
+{
+ struct device_node *np;
+ const __be32 *addr;
+ u32 pa = 0;
+
+ for_each_matching_node(np, dmtimer_match_table) {
+ if (!dmtimer_is_preferred(np))
+ continue;
+
+ addr = of_get_address(np, 0, NULL, NULL);
+ pa = of_translate_address(np, addr);
+ if (pa) {
+ if (pa == clocksource || pa == clockevent) {
+ pa = 0;
+ continue;
+ }
+
+ of_node_put(np);
+ break;
+ }
+ }
+
+ return pa;
+}
+
+/* Selects the best clocksource and clockevent to use */
+static void __init dmtimer_systimer_select_best(void)
+{
+ dmtimer_systimer_check_counter32k();
+ dmtimer_systimer_assign_alwon();
+
+ if (clockevent == DMTIMER_INST_DONT_CARE)
+ clockevent = dmtimer_systimer_find_first_available();
+
+ pr_debug("%s: counter_32k: %i clocksource: %08x clockevent: %08x\n",
+ __func__, counter_32k, clocksource, clockevent);
+}
+
+/* Interface clocks are only available on some SoCs variants */
+static int __init dmtimer_systimer_init_clock(struct device_node *np,
+ const char *name,
+ unsigned long *rate)
+{
+ struct clk *clock;
+ unsigned long r;
+ int error;
+
+ clock = of_clk_get_by_name(np, name);
+ if ((PTR_ERR(clock) == -EINVAL) && !strncmp(name, "ick", 3))
+ return 0;
+ else if (IS_ERR(clock))
+ return PTR_ERR(clock);
+
+ error = clk_prepare_enable(clock);
+ if (error)
+ return error;
+
+ r = clk_get_rate(clock);
+ if (!r)
+ return -ENODEV;
+
+ *rate = r;
+
+ return 0;
+}
+
+static void dmtimer_systimer_enable(struct dmtimer_systimer *t)
+{
+ u32 val;
+
+ if (dmtimer_systimer_revision1(t))
+ val = DMTIMER_TYPE1_ENABLE;
+ else
+ val = DMTIMER_TYPE2_ENABLE;
+
+ writel_relaxed(val, t->base + t->sysc);
+}
+
+static void dmtimer_systimer_disable(struct dmtimer_systimer *t)
+{
+ writel_relaxed(0, t->base + t->sysc);
+}
+
+static int __init dmtimer_systimer_setup(struct device_node *np,
+ struct dmtimer_systimer *t)
+{
+ unsigned long rate;
+ u8 regbase;
+ int error;
+
+ if (!of_device_is_compatible(np->parent, "ti,sysc"))
+ return -EINVAL;
+
+ t->base = of_iomap(np, 0);
+ if (!t->base)
+ return -ENXIO;
+
+ /*
+ * Enable optional assigned-clock-parents configured at the timer
+ * node level. For regular device drivers, this is done automatically
+ * by bus related code such as platform_drv_probe().
+ */
+ error = of_clk_set_defaults(np, false);
+ if (error < 0)
+ pr_err("%s: clock source init failed: %i\n", __func__, error);
+
+ /* For ti-sysc, we have timer clocks at the parent module level */
+ error = dmtimer_systimer_init_clock(np->parent, "fck", &rate);
+ if (error)
+ goto err_unmap;
+
+ t->rate = rate;
+
+ error = dmtimer_systimer_init_clock(np->parent, "ick", &rate);
+ if (error)
+ goto err_unmap;
+
+ if (dmtimer_systimer_revision1(t)) {
+ t->irq_stat = OMAP_TIMER_V1_STAT_OFFSET;
+ t->irq_ena = OMAP_TIMER_V1_INT_EN_OFFSET;
+ t->pend = _OMAP_TIMER_WRITE_PEND_OFFSET;
+ regbase = 0;
+ } else {
+ t->irq_stat = OMAP_TIMER_V2_IRQSTATUS;
+ t->irq_ena = OMAP_TIMER_V2_IRQENABLE_SET;
+ regbase = OMAP_TIMER_V2_FUNC_OFFSET;
+ t->pend = regbase + _OMAP_TIMER_WRITE_PEND_OFFSET;
+ }
+
+ t->sysc = OMAP_TIMER_OCP_CFG_OFFSET;
+ t->load = regbase + _OMAP_TIMER_LOAD_OFFSET;
+ t->counter = regbase + _OMAP_TIMER_COUNTER_OFFSET;
+ t->ctrl = regbase + _OMAP_TIMER_CTRL_OFFSET;
+ t->wakeup = regbase + _OMAP_TIMER_WAKEUP_EN_OFFSET;
+ t->ifctrl = regbase + _OMAP_TIMER_IF_CTRL_OFFSET;
+
+ dmtimer_systimer_enable(t);
+ dmtimer_systimer_reset(t);
+ pr_debug("dmtimer rev %08x sysc %08x\n", readl_relaxed(t->base),
+ readl_relaxed(t->base + t->sysc));
+
+ return 0;
+
+err_unmap:
+ iounmap(t->base);
+
+ return error;
+}
+
+/* Clockevent */
+static struct dmtimer_clockevent *
+to_dmtimer_clockevent(struct clock_event_device *clockevent)
+{
+ return container_of(clockevent, struct dmtimer_clockevent, dev);
+}
+
+static irqreturn_t dmtimer_clockevent_interrupt(int irq, void *data)
+{
+ struct dmtimer_clockevent *clkevt = data;
+ struct dmtimer_systimer *t = &clkevt->t;
+
+ writel_relaxed(OMAP_TIMER_INT_OVERFLOW, t->base + t->irq_stat);
+ clkevt->dev.event_handler(&clkevt->dev);
+
+ return IRQ_HANDLED;
+}
+
+static int dmtimer_set_next_event(unsigned long cycles,
+ struct clock_event_device *evt)
+{
+ struct dmtimer_clockevent *clkevt = to_dmtimer_clockevent(evt);
+ struct dmtimer_systimer *t = &clkevt->t;
+ void __iomem *pend = t->base + t->pend;
+
+ writel_relaxed(0xffffffff - cycles, t->base + t->counter);
+ while (readl_relaxed(pend) & WP_TCRR)
+ cpu_relax();
+
+ writel_relaxed(OMAP_TIMER_CTRL_ST, t->base + t->ctrl);
+ while (readl_relaxed(pend) & WP_TCLR)
+ cpu_relax();
+
+ return 0;
+}
+
+static int dmtimer_clockevent_shutdown(struct clock_event_device *evt)
+{
+ struct dmtimer_clockevent *clkevt = to_dmtimer_clockevent(evt);
+ struct dmtimer_systimer *t = &clkevt->t;
+ void __iomem *ctrl = t->base + t->ctrl;
+ u32 l;
+
+ l = readl_relaxed(ctrl);
+ if (l & OMAP_TIMER_CTRL_ST) {
+ l &= ~BIT(0);
+ writel_relaxed(l, ctrl);
+ /* Flush posted write */
+ l = readl_relaxed(ctrl);
+ /* Wait for functional clock period x 3.5 */
+ udelay(3500000 / t->rate + 1);
+ }
+ writel_relaxed(OMAP_TIMER_INT_OVERFLOW, t->base + t->irq_stat);
+
+ return 0;
+}
+
+static int dmtimer_set_periodic(struct clock_event_device *evt)
+{
+ struct dmtimer_clockevent *clkevt = to_dmtimer_clockevent(evt);
+ struct dmtimer_systimer *t = &clkevt->t;
+ void __iomem *pend = t->base + t->pend;
+
+ dmtimer_clockevent_shutdown(evt);
+
+ /* Looks like we need to first set the load value separately */
+ writel_relaxed(clkevt->period, t->base + t->load);
+ while (readl_relaxed(pend) & WP_TLDR)
+ cpu_relax();
+
+ writel_relaxed(clkevt->period, t->base + t->counter);
+ while (readl_relaxed(pend) & WP_TCRR)
+ cpu_relax();
+
+ writel_relaxed(OMAP_TIMER_CTRL_AR | OMAP_TIMER_CTRL_ST,
+ t->base + t->ctrl);
+ while (readl_relaxed(pend) & WP_TCLR)
+ cpu_relax();
+
+ return 0;
+}
+
+static void omap_clockevent_idle(struct clock_event_device *evt)
+{
+ struct dmtimer_clockevent *clkevt = to_dmtimer_clockevent(evt);
+ struct dmtimer_systimer *t = &clkevt->t;
+
+ dmtimer_systimer_disable(t);
+}
+
+static void omap_clockevent_unidle(struct clock_event_device *evt)
+{
+ struct dmtimer_clockevent *clkevt = to_dmtimer_clockevent(evt);
+ struct dmtimer_systimer *t = &clkevt->t;
+
+ dmtimer_systimer_enable(t);
+ writel_relaxed(OMAP_TIMER_INT_OVERFLOW, t->base + t->irq_ena);
+ writel_relaxed(OMAP_TIMER_INT_OVERFLOW, t->base + t->wakeup);
+}
+
+static int __init dmtimer_clockevent_init(struct device_node *np)
+{
+ struct dmtimer_clockevent *clkevt;
+ struct clock_event_device *dev;
+ struct dmtimer_systimer *t;
+ int error;
+ u32 pa;
+
+ clkevt = kzalloc(sizeof(*clkevt), GFP_KERNEL);
+ if (!clkevt)
+ return -ENOMEM;
+
+ t = &clkevt->t;
+ dev = &clkevt->dev;
+
+ /*
+ * 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->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->tick_resume = dmtimer_clockevent_shutdown;
+ dev->cpumask = cpu_possible_mask;
+
+ dev->irq = irq_of_parse_and_map(np, 0);
+ if (!dev->irq) {
+ error = -ENXIO;
+ goto err_out_free;
+ }
+
+ error = dmtimer_systimer_setup(np, &clkevt->t);
+ if (error)
+ goto err_out_free;
+
+ clkevt->period = 0xffffffff - DIV_ROUND_CLOSEST(t->rate, HZ);
+
+ /*
+ * For clock-event timers we never read the timer counter and
+ * so we are not impacted by errata i103 and i767. Therefore,
+ * we can safely ignore this errata for clock-event timers.
+ */
+ writel_relaxed(OMAP_TIMER_CTRL_POSTED, t->base + t->ifctrl);
+
+ error = request_irq(dev->irq, dmtimer_clockevent_interrupt,
+ IRQF_TIMER, "clockevent", 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);
+
+ pa = of_translate_address(np, of_get_address(np, 0, NULL, NULL));
+ pr_info("TI gptimer clockevent: %s%lu Hz at %pOF\n",
+ of_find_property(np, "ti,timer-alwon", NULL) ?
+ "always-on " : "", t->rate, np->parent);
+
+ clockevents_config_and_register(dev, t->rate,
+ 3, /* Timer internal resynch latency */
+ 0xffffffff);
+
+ if (of_device_is_compatible(np, "ti,am33xx") ||
+ of_device_is_compatible(np, "ti,am43")) {
+ dev->suspend = omap_clockevent_idle;
+ dev->resume = omap_clockevent_unidle;
+ }
+
+ return 0;
+
+err_out_unmap:
+ iounmap(t->base);
+
+err_out_free:
+ kfree(clkevt);
+
+ return error;
+}
+
+/* Clocksource */
+static struct dmtimer_clocksource *
+to_dmtimer_clocksource(struct clocksource *cs)
+{
+ return container_of(cs, struct dmtimer_clocksource, dev);
+}
+
+static u64 dmtimer_clocksource_read_cycles(struct clocksource *cs)
+{
+ struct dmtimer_clocksource *clksrc = to_dmtimer_clocksource(cs);
+ struct dmtimer_systimer *t = &clksrc->t;
+
+ return (u64)readl_relaxed(t->base + t->counter);
+}
+
+static void __iomem *dmtimer_sched_clock_counter;
+
+static u64 notrace dmtimer_read_sched_clock(void)
+{
+ return readl_relaxed(dmtimer_sched_clock_counter);
+}
+
+static void dmtimer_clocksource_suspend(struct clocksource *cs)
+{
+ struct dmtimer_clocksource *clksrc = to_dmtimer_clocksource(cs);
+ struct dmtimer_systimer *t = &clksrc->t;
+
+ clksrc->loadval = readl_relaxed(t->base + t->counter);
+ dmtimer_systimer_disable(t);
+}
+
+static void dmtimer_clocksource_resume(struct clocksource *cs)
+{
+ struct dmtimer_clocksource *clksrc = to_dmtimer_clocksource(cs);
+ struct dmtimer_systimer *t = &clksrc->t;
+
+ dmtimer_systimer_enable(t);
+ writel_relaxed(clksrc->loadval, t->base + t->counter);
+ writel_relaxed(OMAP_TIMER_CTRL_ST | OMAP_TIMER_CTRL_AR,
+ t->base + t->ctrl);
+}
+
+static int __init dmtimer_clocksource_init(struct device_node *np)
+{
+ struct dmtimer_clocksource *clksrc;
+ struct dmtimer_systimer *t;
+ struct clocksource *dev;
+ int error;
+ u32 pa;
+
+ clksrc = kzalloc(sizeof(*clksrc), GFP_KERNEL);
+ if (!clksrc)
+ return -ENOMEM;
+
+ dev = &clksrc->dev;
+ t = &clksrc->t;
+
+ error = dmtimer_systimer_setup(np, t);
+ if (error)
+ goto err_out_free;
+
+ dev->name = "dmtimer";
+ dev->rating = 300;
+ dev->read = dmtimer_clocksource_read_cycles;
+ dev->mask = CLOCKSOURCE_MASK(32);
+ dev->flags = CLOCK_SOURCE_IS_CONTINUOUS;
+
+ if (of_device_is_compatible(np, "ti,am33xx") ||
+ of_device_is_compatible(np, "ti,am43")) {
+ dev->suspend = dmtimer_clocksource_suspend;
+ dev->resume = dmtimer_clocksource_resume;
+ }
+
+ writel_relaxed(0, t->base + t->counter);
+ writel_relaxed(OMAP_TIMER_CTRL_ST | OMAP_TIMER_CTRL_AR,
+ t->base + t->ctrl);
+
+ pa = of_translate_address(np, of_get_address(np, 0, NULL, NULL));
+ pr_info("TI gptimer clocksource: %s%pOF\n",
+ of_find_property(np, "ti,timer-alwon", NULL) ?
+ "always-on " : "", np->parent);
+
+ if (!dmtimer_sched_clock_counter) {
+ dmtimer_sched_clock_counter = t->base + t->counter;
+ sched_clock_register(dmtimer_read_sched_clock, 32, t->rate);
+ }
+
+ if (clocksource_register_hz(dev, t->rate))
+ pr_err("Could not register clocksource %pOF\n", np);
+
+ return 0;
+
+err_out_free:
+ kfree(clksrc);
+
+ return -ENODEV;
+}
+
+/*
+ * To detect between a clocksource and clockevent, we assume the device tree
+ * has no interrupts configured for a clocksource timer.
+ */
+static int __init dmtimer_systimer_init(struct device_node *np)
+{
+ const __be32 *addr;
+ u32 pa;
+
+ /* One time init for the preferred timer configuration */
+ if (!clocksource && !clockevent)
+ dmtimer_systimer_select_best();
+
+ if (!clocksource && !clockevent) {
+ pr_err("%s: unable to detectt system timers, update dtb?\n",
+ __func__);
+
+ return -EINVAL;
+ }
+
+ addr = of_get_address(np, 0, NULL, NULL);
+ pa = of_translate_address(np, addr);
+ if (!pa)
+ return -EINVAL;
+
+ if (counter_32k <= 0 && clocksource == pa)
+ return dmtimer_clocksource_init(np);
+
+ if (clockevent == pa)
+ return dmtimer_clockevent_init(np);
+
+ return 0;
+}
+
+TIMER_OF_DECLARE(systimer_omap2, "ti,omap2420-timer", dmtimer_systimer_init);
+TIMER_OF_DECLARE(systimer_omap3, "ti,omap3430-timer", dmtimer_systimer_init);
+TIMER_OF_DECLARE(systimer_omap4, "ti,omap4430-timer", dmtimer_systimer_init);
+TIMER_OF_DECLARE(systimer_omap5, "ti,omap5430-timer", dmtimer_systimer_init);
+TIMER_OF_DECLARE(systimer_am33x, "ti,am335x-timer", dmtimer_systimer_init);
+TIMER_OF_DECLARE(systimer_am3ms, "ti,am335x-timer-1ms", dmtimer_systimer_init);
+TIMER_OF_DECLARE(systimer_dm814, "ti,dm814-timer", dmtimer_systimer_init);
+TIMER_OF_DECLARE(systimer_dm816, "ti,dm816-timer", dmtimer_systimer_init);