[RFC 5/5] powerpc/fsl: Add supported-irq-ranges for P2020

[Bharat Bhushan]

> -----Original Message-----
> From: Scott Wood [mailto:oss at buserror.net]
> Sent: Wednesday, August 8, 2018 2:44 AM
> To: Bharat Bhushan <bharat.bhushan at nxp.com>;
> benh at kernel.crashing.org; paulus at samba.org; mpe at ellerman.id.au;
> galak at kernel.crashing.org; mark.rutland at arm.com;
> kstewart at linuxfoundation.org; gregkh at linuxfoundation.org;
> devicetree at vger.kernel.org; linuxppc-dev at lists.ozlabs.org; linux-
> kernel at vger.kernel.org
> Cc: robh at kernel.org; keescook at chromium.org; tyreld at linux.vnet.ibm.com;
> joe at perches.com
> Subject: Re: [RFC 5/5] powerpc/fsl: Add supported-irq-ranges for P2020
> 
> On Fri, 2018-07-27 at 15:18 +0530, Bharat Bhushan wrote:
> > MPIC on NXP (Freescale) P2020 supports following irq
> > ranges:
> >   > 0 - 11      (External interrupt)
> >   > 16 - 79     (Internal interrupt)
> >   > 176 - 183   (Messaging interrupt)
> >   > 224 - 231   (Shared message signaled interrupt)
> 
> Why don't you convert to the 4-cell interrupt specifiers that make dealing
> with these ranges less error-prone?

Ok , will do if we agree to have this series as per comment on other patch.

> 
> > diff --git a/arch/powerpc/platforms/85xx/mpc85xx_rdb.c
> > b/arch/powerpc/platforms/85xx/mpc85xx_rdb.c
> > index 1006950..49ff348 100644
> > --- a/arch/powerpc/platforms/85xx/mpc85xx_rdb.c
> > +++ b/arch/powerpc/platforms/85xx/mpc85xx_rdb.c
> > @@ -57,6 +57,11 @@ void __init mpc85xx_rdb_pic_init(void)
> >  			MPIC_BIG_ENDIAN |
> >  			MPIC_SINGLE_DEST_CPU,
> >  			0, 256, " OpenPIC  ");
> > +	} else if (of_machine_is_compatible("fsl,P2020RDB-PC")) {
> > +		mpic = mpic_alloc(NULL, 0,
> > +		  MPIC_BIG_ENDIAN |
> > +		  MPIC_SINGLE_DEST_CPU,
> > +		  0, 0, " OpenPIC  ");
> >  	} else {
> >  		mpic = mpic_alloc(NULL, 0,
> >  		  MPIC_BIG_ENDIAN |
> 
> I don't think we want to grow a list of every single revision of every board in
> these platform files.

One other confusing observation I have is that "irq_count" from platform code is given precedence over "last-interrupt-source" in device-tree.
Should not device-tree should have precedence otherwise there is no point using " last-interrupt-source" if platform code passes "irq_count" in mpic_alloc().

Thanks
-Bharat

> 
> -Scott