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From: Marc Zyngier <>
To: valmiki <>,
	Catalin Marinas <>
Subject: Re: Affinity for GIC irq line
Date: Wed, 25 Apr 2018 08:07:31 +0100	[thread overview]
Message-ID: <> (raw)
In-Reply-To: <>

On 25/04/18 04:23, valmiki wrote:
> Hi all,
> When an IRQ line is set affinity using irq_set_affinity, which calls 
> irq_do_set_affinity, this API copies affinity mask to affinity variable 
> in irq_common_data of this irq descriptor.

It does a wee bit more. Crucially, it contains the line:

        ret = chip->irq_set_affinity(data, mask, force);

> But as per ARM GICv2 document in order to drive a interrupt to a 
> specific CPU we need to program GICD_ITARGETSRn register.
> But irq_set_affinity isn't writing to this register.Please correct me if 
> I'm wrong i did not find code for this register being updated in 
> irq_set_affinity flow.
> So how affinity is being set for an IRQ line ?

I would have though that a function name such as "gic_set_affinity" was
clear enough?

> If affinity was set successfully on what CPU does asm_do_IRQ run ?

It runs on the CPU that the interrupt targets, I'd say.

Jazz is not dead. It just smells funny...

  reply	other threads:[~2018-04-25  7:07 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-04-25  3:23 valmiki
2018-04-25  7:07 ` Marc Zyngier [this message]
2018-04-26  3:49   ` valmiki

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