From mboxrd@z Thu Jan 1 00:00:00 1970 From: Scott Wood Subject: Re: [PATCH v5] powerpc/mpc85xx: Update the clock nodes in device tree Date: Mon, 14 Oct 2013 17:13:06 -0500 Message-ID: <1381788786.7979.643.camel@snotra.buserror.net> References: <1381300704-4238-1-git-send-email-Yuantian.Tang@freescale.com> <20131010100331.GE26954@e106331-lin.cambridge.arm.com> <20131011092526.GE3910@e106331-lin.cambridge.arm.com> <1381518433.7979.536.camel@snotra.buserror.net> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Tang Yuantian-B29983 Cc: Wood Scott-B07421 , Mark Rutland , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linuxppc-dev-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org" , Li Yang-Leo-R58472 List-Id: devicetree@vger.kernel.org On Fri, 2013-10-11 at 21:52 -0500, Tang Yuantian-B29983 wrote: > Thanks for your review. >=20 > > -----Original Message----- > > From: Wood Scott-B07421 > > Sent: 2013=E5=B9=B410=E6=9C=8812=E6=97=A5 =E6=98=9F=E6=9C=9F=E5=85=AD= 3:07 > > To: Mark Rutland > > Cc: Tang Yuantian-B29983; devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org; linuxppc- > > dev-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org; Li Yang-Leo-R58472 > > Subject: Re: [PATCH v5] powerpc/mpc85xx: Update the clock nodes in = device > > tree > >=20 > > I'm not sure I understand the "_0"/"_1" part, though. Doesn't each= PLL > > just have one output, which the consumer may choose to divide by 2 = (or in > > some cases 4)? Why does that division need to be exposed in the de= vice > > tree as separate connections to the parent clock? > >=20 > The device tree makes that quite clear.=20 You chose to model it that way in the device tree; that doesn't make it clear that the hardware works that way or that it's a good way to model it. > Each PLL has several output which MUX node can take from. Point out where in the hardware documentation it says this. What I see is a PLL that has one output, and a MUX register that can choose from multiple PLL and divider options. > It is not a runtime decision. Hmm? It's a register you write to. -Scott -- To unsubscribe from this list: send the line "unsubscribe devicetree" i= n the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html