RE: [PATCH] powerpc/dts: Add 1588 timer node for eTSEC

[yangbo.lu@xxxxxxxxxxxxx]

-----Original Message-----
From: Wood Scott-B07421 
Sent: Thursday, May 07, 2015 10:35 AM
To: Lu Yangbo-B47093
Cc: linuxppc-dev@xxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
Subject: Re: [PATCH] powerpc/dts: Add 1588 timer node for eTSEC

On Wed, 2015-05-06 at 21:26 -0500, Lu Yangbo-B47093 wrote:
> Thanks.
> Pls see my comments below.
> 
> -----Original Message-----
> From: Wood Scott-B07421
> Sent: Thursday, May 07, 2015 4:44 AM
> To: Lu Yangbo-B47093
> Cc: linuxppc-dev@xxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH] powerpc/dts: Add 1588 timer node for eTSEC
> 
> On Wed, 2015-05-06 at 17:40 +0800, Yangbo Lu wrote:
> > Add 1588 timer node in files:
> > arch/powerpc/boot/dts/bsc9131rdb.dtsi
> > arch/powerpc/boot/dts/bsc9132qds.dtsi
> > arch/powerpc/boot/dts/p1010rdb.dtsi
> > arch/powerpc/boot/dts/p1020rdb-pd.dts
> > arch/powerpc/boot/dts/p1021rdb-pc.dtsi
> > arch/powerpc/boot/dts/p1022ds.dtsi
> > arch/powerpc/boot/dts/p1025twr.dtsi
> > arch/powerpc/boot/dts/p2020rdb-pc.dtsi
> > 
> > Signed-off-by: Yangbo Lu <yangbo.lu@xxxxxxxxxxxxx>
> > ---
> >  arch/powerpc/boot/dts/bsc9131rdb.dtsi  | 12 ++++++++++++ 
> > arch/powerpc/boot/dts/bsc9132qds.dtsi  | 12 ++++++++++++
> >  arch/powerpc/boot/dts/p1010rdb.dtsi    | 12 ++++++++++++
> >  arch/powerpc/boot/dts/p1020rdb-pd.dts  | 12 ++++++++++++ 
> > arch/powerpc/boot/dts/p1021rdb-pc.dtsi | 12 ++++++++++++
> >  arch/powerpc/boot/dts/p1022ds.dtsi     | 12 ++++++++++++
> >  arch/powerpc/boot/dts/p1025twr.dtsi    | 12 ++++++++++++
> >  arch/powerpc/boot/dts/p2020rdb-pc.dtsi | 15 +++++++++------
> >  8 files changed, 93 insertions(+), 6 deletions(-)
> > 
> > diff --git a/arch/powerpc/boot/dts/bsc9131rdb.dtsi
> > b/arch/powerpc/boot/dts/bsc9131rdb.dtsi
> > index 45efcba..629cc03 100644
> > --- a/arch/powerpc/boot/dts/bsc9131rdb.dtsi
> > +++ b/arch/powerpc/boot/dts/bsc9131rdb.dtsi
> > @@ -80,6 +80,18 @@
> >  		status = "disabled";
> >  	};
> >  
> > +	ptp_clock@b0e00 {
> > +		compatible = "fsl,etsec-ptp";
> > +		reg = <0xb0e00 0xb0>;
> > +		interrupts = <68 2 0 0 69 2 0 0>;
> > +		fsl,tclk-period	= <5>;
> > +		fsl,tmr-prsc	= <2>;
> > +		fsl,tmr-add	= <0xcccccccd>;
> > +		fsl,tmr-fiper1	= <0x3b9ac9fb>;
> > +		fsl,tmr-fiper2	= <0x00018696>;
> > +		fsl,max-adj	= <249999999>;
> 
> Please don't use hex for numbers that make more sense as decimal.
> [Lu Yangbo-B47093] The hex value is register value, I think it's better to use hex.

Whether it goes into a register doesn't matter.  Hex values are useful for values which are subdivided into various bitfields, or whose hex representation is simpler than decimal.  I'm not familiar with the details of this hardware, but I doubt the former is the case for 0x3b9ac9fb == 9999999995 or 0x18696 == 99990.
[Lu Yangbo-B47093] Thanks Scott. I got it. The hex value here is not for various bitfields but a value calculated manually. I will modify to decimalism.

-Scott