int __init metag_generic_timer_init(void)
{
/*
* On Meta 2 SoCs, the actual frequency of the timer is based on the
* Meta core clock speed divided by an integer, so it is only
* approximately 1MHz. Calculating the real frequency here drastically
* reduces clock skew on these SoCs.
*/
#ifdef CONFIG_METAG_META21
hwtimer_freq = get_coreclock() / (metag_in32(EXPAND_TIMER_DIV) + 1);
#endif
pr_info("Timer frequency: %u Hz\n", hwtimer_freq);
clocksource_register_hz(&clocksource_metag, hwtimer_freq);
setup_irq(tbisig_map(TBID_SIGNUM_TRT), &metag_timer_irq);
/* Configure timer on boot CPU */
arch_timer_setup(smp_processor_id());
/* Hook cpu boot to configure other CPU's timers */
register_cpu_notifier(&arch_timer_cpu_nb);
return 0;
}
static void arch_timer_setup(unsigned int cpu)
{
unsigned int txdivtime;
struct clock_event_device *clk = &per_cpu(local_clockevent, cpu);
char *name = per_cpu(local_clockevent_name, cpu);
txdivtime = __core_reg_get(TXDIVTIME);
txdivtime &= ~TXDIVTIME_DIV_BITS;
txdivtime |= (HARDWARE_DIV & TXDIVTIME_DIV_BITS);
__core_reg_set(TXDIVTIME, txdivtime);
sprintf(name, "META %d", cpu);
clk->name = name;
clk->features = CLOCK_EVT_FEAT_ONESHOT,
clk->rating = 200,
clk->shift = 12,
clk->irq = tbisig_map(TBID_SIGNUM_TRT),
clk->set_mode = metag_timer_set_mode,
clk->set_next_event = metag_timer_set_next_event,
clk->mult = div_sc(hwtimer_freq, NSEC_PER_SEC, clk->shift);
clk->max_delta_ns = clockevent_delta2ns(0x7fffffff, clk);
clk->min_delta_ns = clockevent_delta2ns(0xf, clk);
clk->cpumask = cpumask_of(cpu);
clockevents_register_device(clk);
/*
* For all non-boot CPUs we need to synchronize our free
* running clock (TXTIMER) with the boot CPU's clock.
*
* While this won't be accurate, it should be close enough.
*/
if (cpu) {
unsigned int thread0 = cpu_2_hwthread_id[0];
unsigned long val;
val = core_reg_read(TXUCT_ID, TXTIMER_REGNUM, thread0);
__core_reg_set(TXTIMER, val);
}
}
int __init metag_generic_timer_init(void)
{
/*
* On Meta 2 SoCs, the actual frequency of the timer is based on the
* Meta core clock speed divided by an integer, so it is only
* approximately 1MHz. Calculating the real frequency here drastically
* reduces clock skew on these SoCs.
*/
#ifdef CONFIG_METAG_META21
hwtimer_freq = get_coreclock() / (metag_in32(EXPAND_TIMER_DIV) + 1);
#endif
pr_info("Timer frequency: %u Hz\n", hwtimer_freq);
clocksource_register_hz(&clocksource_metag, hwtimer_freq);
setup_irq(tbisig_map(TBID_SIGNUM_TRT), &metag_timer_irq);
/* Hook cpu boot to configure the CPU's timers */
return cpuhp_setup_state(CPUHP_AP_METAG_TIMER_STARTING,
"clockevents/metag:starting",
arch_timer_starting_cpu, NULL);
}