On Wednesday 13 April 2016 06:29 PM, Daniel Lezcano wrote:
> On Wed, Apr 13, 2016 at 05:10:01PM +0530, Vineet Gupta wrote:
>> - timer frequency is derived from DT (no longer rely on top level
>> DT "clock-frequency" probed early and exported by asm/clk.h)
>>
>> - TIMER0_IRQ need not be exported across arch code, confined to intc as
>> it is property of same
>>
>> Cc: Daniel Lezcano <daniel.lezc...@linaro.org>
>> Signed-off-by: Vineet Gupta <vgu...@synopsys.com>
>> ---
>
> [ ... ]
>
>> +static void noinline arc_get_timer_clk(struct device_node *node)
>> +{
>> + struct clk *clk;
>> + int ret;
>> +
>> + clk = of_clk_get(node, 0);
>> + if (IS_ERR(clk))
>> + panic("Can't get timer clock");
>> +
>
> Don't panic here. Change the function to return an error and let the
> caller to handle it.
>
>> + ret = clk_prepare_enable(clk);
>> + if (ret)
>> + pr_err("Couldn't enable parent clock\n");
I suppose we need to return here too ?
>> +
>> + arc_timer_freq = clk_get_rate(clk);
>> +}
>> +
>
> [ ... ]
>
>> +static void __init arc_clockevent_setup(struct device_node *node)
>> {
>> struct clock_event_device *evt = this_cpu_ptr(&arc_clockevent_device);
>> int ret;
>>
>> register_cpu_notifier(&arc_timer_cpu_nb);
>>
>> + arc_timer_irq = irq_of_parse_and_map(node, 0);
>> + if (arc_timer_irq <= 0)
>> + panic("Can't parse IRQ");
>> +
>> + arc_get_timer_clk(node);
>
> Connected to the comment above, check the return code.
Right and if there's error, bail from here too ? This will leave a system w/o a
working clockevent and our lpj setup loop will spin forever. Better to add a
WARN
so that user knows to fix his DT.
>
>> +
>> + evt->irq = arc_timer_irq;
>> evt->cpumask = cpumask_of(smp_processor_id());
>> - clockevents_config_and_register(evt, arc_get_core_freq(),
>> + clockevents_config_and_register(evt, arc_timer_freq,
>> 0, ARC_TIMER_MAX);
>>
>> /* Needs apriori irq_set_percpu_devid() done in intc map function */
>> @@ -291,6 +312,7 @@ static void __init arc_clockevent_setup(void)
>>
>> enable_percpu_irq(arc_timer_irq, 0);
>> }
>> +CLOCKSOURCE_OF_DECLARE(arc_clkevt, "snps,arc-timer", arc_clockevent_setup);
>>
>> /*
>> * Called from start_kernel() - boot CPU only
>> @@ -299,7 +321,6 @@ static void __init arc_clockevent_setup(void)
>> * -Also sets up any global state needed for timer subsystem:
>> * - for "counting" timer, registers a clocksource, usable across CPUs
>> * (provided that underlying counter h/w is synchronized across cores)
>> - * - for "event" timer, sets up TIMER0 IRQ (as that is platform agnostic)
>> */
>> void __init time_init(void)
>> {
>> @@ -315,7 +336,5 @@ void __init time_init(void)
>> * CLK upto 4.29 GHz can be safely represented in 32 bits
>> * because Max 32 bit number is 4,294,967,295
>> */
>> - clocksource_register_hz(&arc_counter, arc_get_core_freq());
>> -
>> - arc_clockevent_setup();
>> + clocksource_register_hz(&arc_counter, arc_timer_freq);
>> }
>> --
>> 2.5.0
>>
>
_______________________________________________
linux-snps-arc mailing list
linux-snps-arc@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-snps-arc
