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Subject: Re: Ask help about killing irqchip.irq_print_chip on PPC platforms
From: Scott Wood <scottwood@freescale.com>
To: Jiang Liu <jiang.liu@linux.intel.com>
Date: Tue, 23 Dec 2014 01:58:49 -0600
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Cc: Tudor Laurentiu <b10716@freescale.com>,
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On Tue, 2014-12-23 at 15:56 +0800, Jiang Liu wrote:
> Hi Scott and Tudor,
> 	Sorry, resend and Ccing the list.

Resending reply...

> 	We are trying to clean up some irqchip interfaces, and
> irqchip.irq_print_chip is a candidate for removal. After some
> changes on x86 side, arch/powerpc/sysdev/fsl_msi.c may be the
> last user of irqchip.irq_print_chip. So could you please help
> to advice on whether we could kill irqchip.irq_print_chip
> by using "fsl-msi" instead of "fsl-msi-%d" for irqchip name?
> Will it break any userspace interfaces?
> Thanks!
> Gerry

fsl-msi-%d was introduced to allow userspace to identify the cascade
interrupt belonging to a particular MSI, for the purpose of setting
affinity, as this cannot be done on the MSI itself due to hardware
limitations.

Removing it would not exactly eliminate a lot of code or complexity...

-Scott