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Date: Fri, 31 Oct 2014 12:28:20 +0100
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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To: Johannes Thumshirn <johannes.thumshirn@men.de>,
 Michael Ellerman <mpe@ellerman.id.au>
Subject: Re: FSL MSI Mapping
References: <20141028170604.GA1536@jtlinux>
 <1414641117.12600.4.camel@concordia> <20141031081225.GA20831@jtlinux>
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On 10/31/2014 09:12 AM, Johannes Thumshirn wrote:
> On Thu, Oct 30, 2014 at 02:51:57PM +1100, Michael Ellerman wrote:
>> Why would you not use MSI-X ?

If I'm not mistaken, a PCI-E requirement is to support MSI but MSI-X is
optional. And with MSI you can have multiple interrupts per single
device (power of two, max 32).
Now imagine you have a FPGA with two (or more) different devices in it
and you don't want them to share the IRQ line (for $reason). I bet the
HW developer sees MSI and MSI-X and the former is for some reason
cheaper compared to MSI-X and it fits the needs. So…

> 
> Does anyone (especially the original author) have any objections if I re-spin
> the patch series?

I didn't get around to address the review comments so it did not went
in and there was no v2. Feel free re-do the series.

Sebastian