Re: [PATCH v2 04/19] irqchip: add nps Internal and external irqchips

From: Noam Camus
Date: Sat Nov 07 2015 - 15:52:21 EST


>From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
>Sent: Saturday, November 7, 2015 1:38 PM

>> + /*
>> + * GIM interrupt select type for
>> + * dbg_lan TX and RX interrupts
>> + * should be type 1
>> + * type 0 = IRQ line 6
>> + * type 1 = IRQ line 7
>> + */
>> + gim_p_int_dst.is = 1;

>More magic structs to set a single bit, right?
I will replace all such magic with macros.

>> + ienb &= ~(1 << data->irq);

>You should not rely on data->irq ever. It's the Linux interrupt number
>and it does not necessarily have a 1:1 mapping to the hardware
>nterrupt number. Its working for legacy domains, but there
>data->hwirq is set up for you as well.
Thanks, I will use data->hwirq instead of data->irq.


>> + write_aux_reg(AUX_IENABLE, ienb);

>I can see how that works for per cpu interrupts, but what happens if
>two cpus run that concurrent for two different interrupts?

Each CPU got its own HW copy of auxiliary register IENABLE, so concurrent access won't be a trouble.

-Noam--
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