[PATCH 3/5] ARM: sa1100: use ioremapped memory to access SC registers

Dmitry Eremin-Solenikov dbaryshkov at gmail.com
Sat Jan 24 09:50:53 PST 2015


2015-01-24 20:48 GMT+03:00 Thomas Gleixner <tglx at linutronix.de>:
> On Thu, 15 Jan 2015, Dmitry Eremin-Solenikov wrote:
>>  static void sa1100_mask_irq(struct irq_data *d)
>>  {
>> -     ICMR &= ~BIT(d->hwirq);
>> +     u32 reg;
>> +     unsigned long flags;
>> +
>> +     raw_spin_lock_irqsave(&lock, flags);
>
> What's the exact point of that lock? And how is it related to the
> $subject of the patch?

It is needed to protect ICMR register during RMW cycle, isn't it?
I might have missed locks around ack/mask/unmask calls from irq
core. If so, I can happily drop this spinlock.

-- 
With best wishes
Dmitry



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