[PATCH 2/4] irqchip: bcm2836: Add SMP support for the 2836

Andrea Merello andrea.merello at gmail.com
Sat Jan 2 08:05:34 PST 2016


Agreed.
This probably comes from the downstream code, I think.. But I agree
it's actually redundant.

Thank you for pointing this out.

On Sat, Jan 2, 2016 at 11:27 AM, Russell King - ARM Linux
<linux at arm.linux.org.uk> wrote:
> On Sat, Dec 26, 2015 at 01:47:22PM -0800, Eric Anholt wrote:
>> +int __init bcm2836_smp_boot_secondary(unsigned int cpu,
>> +                                   struct task_struct *idle)
>> +{
>> +     unsigned long secondary_startup_phys =
>> +             (unsigned long)virt_to_phys((void *)secondary_startup);
>> +
>> +     dsb();
>> +     writel(secondary_startup_phys,
>> +            intc.base + LOCAL_MAILBOX3_SET0 + 16 * cpu);
>
> Please explain why you need this dsb() - I can't see a reason for it.
> writel() has a barrier internally prior to writing the register, and
> therefore I think the above dsb() is entirely redundant.
>
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