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From: Ian Munsie <imunsie@au1.ibm.com>
To: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>, Michael Neuling <mikey@neuling.org>,
 "andrew.donnellan" <andrew.donnellan@au1.ibm.com>,
 linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
 Huy Nguyen <huyn@mellanox.com>
Subject: Re: [PATCH 08/14] cxl: Add kernel APIs to get & set the max irqs per
 context
In-reply-to: <577D49E4.2030803@linux.vnet.ibm.com>
References: <1467638532-9250-1-git-send-email-imunsie@au.ibm.com>
 <1467638532-9250-9-git-send-email-imunsie@au.ibm.com>
 <577D49E4.2030803@linux.vnet.ibm.com>
Date: Thu, 07 Jul 2016 16:00:48 +1000
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Excerpts from Frederic Barrat's message of 2016-07-06 20:11:48 +0200:
> 
> Le 04/07/2016 15:22, Ian Munsie a écrit :
> > From: Ian Munsie <imunsie@au1.ibm.com>
> >
> > These APIs will be used by the Mellanox CX4 support. While they function
> > standalone to configure existing behaviour, their primary purpose is to
> > allow the Mellanox driver to inform the cxl driver of a hardware
> > limitation, which will be used in a future patch.
> >
> > Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
> 
> Any way to add a check that the "set max" API is called before the 
> interrupts are allocated?

I don't think there is any real need - if the set max API has not been
called then we use the maximum number of interrupts possible on the PHB,
which is the correct thing to do if we don't need the workaround. We
could try adding a WARN in the set max API if interrupts have previously
been allocated, but realistically - if a driver developer needs to use
this they already know it and will be testing for it.

Cheers,
-Ian