> -----Original Message----- > From: Scott Wood [mailto:o...@buserror.net] > Sent: Wednesday, August 8, 2018 11:21 AM > To: Bharat Bhushan <bharat.bhus...@nxp.com>; Rob Herring > <r...@kernel.org> > Cc: b...@kernel.crashing.org; pau...@samba.org; m...@ellerman.id.au; > ga...@kernel.crashing.org; mark.rutl...@arm.com; > kstew...@linuxfoundation.org; gre...@linuxfoundation.org; > devicet...@vger.kernel.org; linuxppc-dev@lists.ozlabs.org; linux- > ker...@vger.kernel.org; keesc...@chromium.org; > tyr...@linux.vnet.ibm.com; j...@perches.com > Subject: Re: [RFC 3/5] powerpc/mpic: Add support for non-contiguous irq > ranges > > On Wed, 2018-08-08 at 03:37 +0000, Bharat Bhushan wrote: > > > -----Original Message----- > > > From: Scott Wood [mailto:o...@buserror.net] > > > Sent: Wednesday, August 8, 2018 2:34 AM > > > To: Rob Herring <r...@kernel.org>; Bharat Bhushan > > > <bharat.bhus...@nxp.com> > > > Cc: b...@kernel.crashing.org; pau...@samba.org; m...@ellerman.id.au; > > > ga...@kernel.crashing.org; mark.rutl...@arm.com; > > > kstew...@linuxfoundation.org; gre...@linuxfoundation.org; > > > devicet...@vger.kernel.org; linuxppc-dev@lists.ozlabs.org; linux- > > > ker...@vger.kernel.org; keesc...@chromium.org; > > > tyr...@linux.vnet.ibm.com; j...@perches.com > > > Subject: Re: [RFC 3/5] powerpc/mpic: Add support for non-contiguous > > > irq ranges > > > > > > On Tue, 2018-08-07 at 12:09 -0600, Rob Herring wrote: > > > > On Fri, Jul 27, 2018 at 03:17:59PM +0530, Bharat Bhushan wrote: > > > > > Freescale MPIC h/w may not support all interrupt sources > > > > > reported by hardware, "last-interrupt-source" or platform. On > > > > > these platforms a misconfigured device tree that assigns one of > > > > > the reserved interrupts leaves a non-functioning system without > warning. > > > > > > > > There are lots of ways to misconfigure DTs. I don't think this is > > > > special and needs a property. > > > > > > Yeah, the system will be just as non-functioning if you specify a > > > valid- > > > but- > > > wrong-for-the-device interrupt number. > > > > Some is one additional benefits of this changes, MPIC have reserved > > regions for un-supported interrupts and read/writes to these reserved > > regions seams have no effect. > > MPIC driver reads/writes to the reserved regions during init/uninit > > and save/restore state. > > > > Let me know if it make sense to have these changes for mentioned > reasons. > > The driver has been doing this forever with no ill effect.
Yes, there are no issue reported > What is the motivation for this change? On Simulation model I see warning when accessing the reserved region, So this patch is just an effort to improve. Thanks -Bharat > > -Scott
