From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from na01-bl2-obe.outbound.protection.outlook.com (mail-bl2on0128.outbound.protection.outlook.com [65.55.169.128]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 5406E1A0035 for ; Thu, 13 Nov 2014 19:04:39 +1100 (AEDT) Message-ID: <1415865867.15957.58.camel@freescale.com> Subject: Re: [PATCH] DT: add MDIO node for FMan node From: Scott Wood To: Xie Shaohui-B21989 Date: Thu, 13 Nov 2014 02:04:27 -0600 In-Reply-To: <489ad06fda99436eb3307d613b1f8293@DM2PR0301MB0864.namprd03.prod.outlook.com> References: <1415102196-9238-1-git-send-email-shh.xie@gmail.com> <1415665384.15957.16.camel@freescale.com> <1415727479.15957.29.camel@freescale.com> <1415859399.15957.48.camel@freescale.com> <59c6a8b7ad1d477aad9edd2152d02f8e@DM2PR0301MB0864.namprd03.prod.outlook.com> <1415862913.15957.56.camel@freescale.com> <489ad06fda99436eb3307d613b1f8293@DM2PR0301MB0864.namprd03.prod.outlook.com> Content-Type: text/plain; charset="UTF-8" MIME-Version: 1.0 Cc: Liberman Igal-B31950 , "linuxppc-dev@lists.ozlabs.org" , Medve Emilian-EMMEDVE1 , "devicetree@vger.kernel.org" List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, 2014-11-13 at 02:02 -0600, Xie Shaohui-B21989 wrote: > > > Best Regards, > Shaohui Xie > > > > -----Original Message----- > > From: Wood Scott-B07421 > > Sent: Thursday, November 13, 2014 3:15 PM > > To: Xie Shaohui-B21989 > > Cc: Liberman Igal-B31950; linuxppc-dev@lists.ozlabs.org; > > devicetree@vger.kernel.org; Medve Emilian-EMMEDVE1 > > Subject: Re: [PATCH] DT: add MDIO node for FMan node > > > > On Thu, 2014-11-13 at 01:11 -0600, Xie Shaohui-B21989 wrote: > > > > -----Original Message----- > > > > From: Wood Scott-B07421 > > > > Sent: Thursday, November 13, 2014 2:17 PM > > > > To: Xie Shaohui-B21989 > > > > Cc: Liberman Igal-B31950; linuxppc-dev@lists.ozlabs.org; > > > > devicetree@vger.kernel.org; Medve Emilian-EMMEDVE1 > > > > Subject: Re: [PATCH] DT: add MDIO node for FMan node > > > > > > > > On Wed, 2014-11-12 at 07:40 -0600, Xie Shaohui-B21989 wrote: > > > > > > -----Original Message----- > > > > > > From: Wood Scott-B07421 > > > > > > Sent: Wednesday, November 12, 2014 1:38 AM > > > > > > To: Xie Shaohui-B21989 > > > > > > Cc: Liberman Igal-B31950; linuxppc-dev@lists.ozlabs.org; > > > > > > devicetree@vger.kernel.org; Medve Emilian-EMMEDVE1 > > > > > > Subject: Re: [PATCH] DT: add MDIO node for FMan node > > > > > > > > > > > > On Tue, 2014-11-11 at 04:32 -0600, Xie Shaohui-B21989 wrote: > > > > > > > > -----Original Message----- > > > > > > > > From: Wood Scott-B07421 > > > > > > > > Sent: Tuesday, November 11, 2014 8:23 AM > > > > > > > > To: shh.xie@gmail.com > > > > > > > > Cc: linuxppc-dev@lists.ozlabs.org; > > > > > > > > devicetree@vger.kernel.org; Medve Emilian-EMMEDVE1; Xie > > > > > > > > Shaohui-B21989 > > > > > > > > Subject: Re: [PATCH] DT: add MDIO node for FMan node > > > > > > > > > > > > > > > > On Tue, 2014-11-04 at 19:56 +0800, shh.xie@gmail.com wrote: > > > > > > > > > From: Shaohui Xie > > > > > > > > > > > > > > > > > > This binding is for FMan MDIO, it covers FMan v2 & FMan v3. > > > > > > > > > > > > > > > > > > Signed-off-by: Shaohui Xie > > > > > > > > > --- > > > > > > > > > based on http://patchwork.ozlabs.org/patch/390351/ > > > > > > > > > for 'next' of > > > > > > > > > > > git://git.kernel.org/pub/scm/linux/kernel/git/scottwood/linux. > > > > > > > > > git > > > > > > > > > > > > > > > > Are there any other FMan pieces that are missing from the > > > > > > > > above > > > > patch? > > > > > > > [S.H] I'm adding Igal for this comment. > > > > > > > > > > > > > > > > > > > > > > > > +- bus-frequency > > > > > > > > > + Usage: optional > > > > > > > > > + Value type: > > > > > > > > > + Definition: Default MDIO bus clock speed. > > > > > > > > > > > > > > > > Use clocks/clock-names > > > > > > > [S.H] The MDIO uses Fman clock and divides it to a proper > > > > > > > value which > > > > > > is specified by this property. > > > > > > > > > > > > Use clocks/clock-names to describe that relationship. > > > > > > > > > > > > > > > > [S.H] The MDIO node is sub-node and embedded in Fman node, the > > > > > clocks/clock-names is provided by Fman node, should repeat them in > > > > > MDIO node? For the default MDIO bus clock speed, maybe "clock- > > ranges" > > > > > should be used? > > > > > > > > It's a different clock. You wouldn't be repeating. If it's derived > > > > from the FMan clock, then maybe you don't need anything here (does > > > > the driver know what the divider is, or would that need to be > > > > specified in the device tree?), but no more clock-frequency/bus- > > frequency properties. > > > > > > > [S.H] The purpose here is to get a specific clock frequency, driver to > > use it to calculate the divider. > > > Then the Fman clock can be divided to the frequency. > > > > Oh, so this is stating a desired frequency and not something that already > > exists? What determines this frequency? Is it based on board design, or > > just on the MDIO standard, etc? I'm wondering if the device tree is the > > right place for it. > [S.H] Yes, a desired frequency which is different with MDIO standard. I'm not sure what you mean by "different with". Do you mean "different from"? What does the standard say about frequency? > The Fman clock and the divider determines this frequency. > Since Fman clock is different on different SoCs, so specify the desired frequency, > then to get the proper divider. Why does the fman clock being different mean the mdio clock should be different? -Scott From mboxrd@z Thu Jan 1 00:00:00 1970 From: Scott Wood Subject: Re: [PATCH] DT: add MDIO node for FMan node Date: Thu, 13 Nov 2014 02:04:27 -0600 Message-ID: <1415865867.15957.58.camel@freescale.com> References: <1415102196-9238-1-git-send-email-shh.xie@gmail.com> <1415665384.15957.16.camel@freescale.com> <1415727479.15957.29.camel@freescale.com> <1415859399.15957.48.camel@freescale.com> <59c6a8b7ad1d477aad9edd2152d02f8e@DM2PR0301MB0864.namprd03.prod.outlook.com> <1415862913.15957.56.camel@freescale.com> <489ad06fda99436eb3307d613b1f8293@DM2PR0301MB0864.namprd03.prod.outlook.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <489ad06fda99436eb3307d613b1f8293-Cwg/PA1lyPnq20u2fDgSrZwN6zqB+hSMnBOFsp37pqbUKgpGm//BTAC/G2K4zDHf@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Xie Shaohui-B21989 Cc: Liberman Igal-B31950 , "linuxppc-dev-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org" , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Medve Emilian-EMMEDVE1 List-Id: devicetree@vger.kernel.org On Thu, 2014-11-13 at 02:02 -0600, Xie Shaohui-B21989 wrote: > > > Best Regards, > Shaohui Xie > > > > -----Original Message----- > > From: Wood Scott-B07421 > > Sent: Thursday, November 13, 2014 3:15 PM > > To: Xie Shaohui-B21989 > > Cc: Liberman Igal-B31950; linuxppc-dev-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org; > > devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org; Medve Emilian-EMMEDVE1 > > Subject: Re: [PATCH] DT: add MDIO node for FMan node > > > > On Thu, 2014-11-13 at 01:11 -0600, Xie Shaohui-B21989 wrote: > > > > -----Original Message----- > > > > From: Wood Scott-B07421 > > > > Sent: Thursday, November 13, 2014 2:17 PM > > > > To: Xie Shaohui-B21989 > > > > Cc: Liberman Igal-B31950; linuxppc-dev-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org; > > > > devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org; Medve Emilian-EMMEDVE1 > > > > Subject: Re: [PATCH] DT: add MDIO node for FMan node > > > > > > > > On Wed, 2014-11-12 at 07:40 -0600, Xie Shaohui-B21989 wrote: > > > > > > -----Original Message----- > > > > > > From: Wood Scott-B07421 > > > > > > Sent: Wednesday, November 12, 2014 1:38 AM > > > > > > To: Xie Shaohui-B21989 > > > > > > Cc: Liberman Igal-B31950; linuxppc-dev-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org; > > > > > > devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org; Medve Emilian-EMMEDVE1 > > > > > > Subject: Re: [PATCH] DT: add MDIO node for FMan node > > > > > > > > > > > > On Tue, 2014-11-11 at 04:32 -0600, Xie Shaohui-B21989 wrote: > > > > > > > > -----Original Message----- > > > > > > > > From: Wood Scott-B07421 > > > > > > > > Sent: Tuesday, November 11, 2014 8:23 AM > > > > > > > > To: shh.xie-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org > > > > > > > > Cc: linuxppc-dev-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org; > > > > > > > > devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org; Medve Emilian-EMMEDVE1; Xie > > > > > > > > Shaohui-B21989 > > > > > > > > Subject: Re: [PATCH] DT: add MDIO node for FMan node > > > > > > > > > > > > > > > > On Tue, 2014-11-04 at 19:56 +0800, shh.xie-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org wrote: > > > > > > > > > From: Shaohui Xie > > > > > > > > > > > > > > > > > > This binding is for FMan MDIO, it covers FMan v2 & FMan v3. > > > > > > > > > > > > > > > > > > Signed-off-by: Shaohui Xie > > > > > > > > > --- > > > > > > > > > based on http://patchwork.ozlabs.org/patch/390351/ > > > > > > > > > for 'next' of > > > > > > > > > > > git://git.kernel.org/pub/scm/linux/kernel/git/scottwood/linux. > > > > > > > > > git > > > > > > > > > > > > > > > > Are there any other FMan pieces that are missing from the > > > > > > > > above > > > > patch? > > > > > > > [S.H] I'm adding Igal for this comment. > > > > > > > > > > > > > > > > > > > > > > > > +- bus-frequency > > > > > > > > > + Usage: optional > > > > > > > > > + Value type: > > > > > > > > > + Definition: Default MDIO bus clock speed. > > > > > > > > > > > > > > > > Use clocks/clock-names > > > > > > > [S.H] The MDIO uses Fman clock and divides it to a proper > > > > > > > value which > > > > > > is specified by this property. > > > > > > > > > > > > Use clocks/clock-names to describe that relationship. > > > > > > > > > > > > > > > > [S.H] The MDIO node is sub-node and embedded in Fman node, the > > > > > clocks/clock-names is provided by Fman node, should repeat them in > > > > > MDIO node? For the default MDIO bus clock speed, maybe "clock- > > ranges" > > > > > should be used? > > > > > > > > It's a different clock. You wouldn't be repeating. If it's derived > > > > from the FMan clock, then maybe you don't need anything here (does > > > > the driver know what the divider is, or would that need to be > > > > specified in the device tree?), but no more clock-frequency/bus- > > frequency properties. > > > > > > > [S.H] The purpose here is to get a specific clock frequency, driver to > > use it to calculate the divider. > > > Then the Fman clock can be divided to the frequency. > > > > Oh, so this is stating a desired frequency and not something that already > > exists? What determines this frequency? Is it based on board design, or > > just on the MDIO standard, etc? I'm wondering if the device tree is the > > right place for it. > [S.H] Yes, a desired frequency which is different with MDIO standard. I'm not sure what you mean by "different with". Do you mean "different from"? What does the standard say about frequency? > The Fman clock and the divider determines this frequency. > Since Fman clock is different on different SoCs, so specify the desired frequency, > then to get the proper divider. Why does the fman clock being different mean the mdio clock should be different? -Scott -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html