From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752443AbbLKExj (ORCPT ); Thu, 10 Dec 2015 23:53:39 -0500 Received: from mailout2.w1.samsung.com ([210.118.77.12]:23035 "EHLO mailout2.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751598AbbLKExh (ORCPT ); Thu, 10 Dec 2015 23:53:37 -0500 X-AuditID: cbfec7f4-f79026d00000418a-13-566a56cd6f10 Subject: Re: [PATCH v5 3/7] ARM: dts: Exynos542x/5800: add CPU OPP properties To: Viresh Kumar , Rob Herring References: <1449766729-435-1-git-send-email-b.zolnierkie@samsung.com> <1449766729-435-4-git-send-email-b.zolnierkie@samsung.com> <20151211031646.GL3612@ubuntu> <566A4231.9050608@osg.samsung.com> <20151211033253.GN3612@ubuntu> <566A4A60.8060402@samsung.com> <20151211041349.GO3612@ubuntu> <566A4E82.3040203@samsung.com> <20151211043802.GP3612@ubuntu> Cc: Javier Martinez Canillas , Bartlomiej Zolnierkiewicz , Thomas Abraham , Sylwester Nawrocki , Mike Turquette , Kukjin Kim , Kukjin Kim , Ben Gamari , Tomasz Figa , Lukasz Majewski , Heiko Stuebner , Chanwoo Choi , Kevin Hilman , Tobias Jakobi , Anand Moon , linux-samsung-soc@vger.kernel.org, linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Doug Anderson , Andreas Faerber From: Krzysztof Kozlowski X-Enigmail-Draft-Status: N1110 Message-id: <566A56C6.2000503@samsung.com> Date: Fri, 11 Dec 2015 13:53:26 +0900 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.4.0 MIME-version: 1.0 In-reply-to: <20151211043802.GP3612@ubuntu> Content-type: text/plain; charset=windows-1252 Content-transfer-encoding: 7bit X-Brightmail-Tracker: H4sIAAAAAAAAA02Ra0hTYRjHeXcuO5uOjvcXI4NBGV6mUh/eohtYeIjCpLAoKpeepuaNHRWt MMk0c3ghNWRleS+mJNvMdGrqFINMdKhLTQ21Uti8hEpGpnm0yG/P83t+/+f58FCY/TDuSkXE xLPKGHmUlBTj3WvvBrx7giODfX9We6E0HYe0RbUEUj8fw9HHpWkC9VS1k2h90kIg62yNAFlm /FB2ySCJcqcsGFrueAmQdUIPkG7KTKB+w1MSLWZ3AlTU+1aAXmlHhMj0/iRKb+kUog7rAwJl VgGUUb1AII1hFSDtMnMcMvND6ULmSaoJZxrVY0JGp3lIMqPmZpLRV9xl1rqETF3uBs6p0wDm wy9/5o35Gcbou28zizq3s5JL4sNhbFREIqv0ORoiDr9f/p2M63NJMq604KlAuyMLUBSkD8D2 Zv8sINoonWHfeC2ZBcSUPV0JYEmmAdtqvgJYWDhK8pYDfQZmNuYI+dqRPg378z79TcwIoDGv dDOB0R0krDBM4LxF0vuh/kUFuXXDDWarHuH8aQntASvSbHiM03ugabxSwGMn+iIsa4jgsYS2 gyv545tbRLQn/PF6UcgrGC2Dn00ePMbo3VBfM4vlATv1toT6v6XeZpUATAOc2ITQOO66ItpP xsmjuYQYhSw0NloHth6+1ADKuw4ZAU0Bqa2klIoMtifkiVxytBFACpM6SpqCNpAkTJ58i1XG XlMmRLGcEeykcKmLpNgwf96eVsjj2ZssG8cq/00FlMg1FTDubT57y0RW728X6otziMdzSdwN 3TmnfTLCQRV0745MN4XW4saq3FWTnrtaVRlkL2uuagtLidcE+PoeU+hW+6/aBqbYDEldQrJ/ e33pxMot4yNuAfWGhTnGeXI6dl19xeI56Vywrgrsyh8cLlAeHG06JTqRLj0yAFo11staKc6F y/08MCUn/wOiiDKA7AIAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11.12.2015 13:38, Viresh Kumar wrote: > On 11-12-15, 13:18, Krzysztof Kozlowski wrote: >> We had such configuration before (before df09df6f9ac3). I don't see any >> benefit in what you described. Where is the "thing" to be fixed? It is >> mixed up. The contiguous ordering is easier to read and more natural. > > This is what you are doing today (keeping on one CPU per cluster to > simplify it): > > cpu0: cpu@0 { > device_type = "cpu"; > compatible = "arm,cortex-a15"; > reg = <0x0>; > clock-frequency = <1800000000>; > cci-control-port = <&cci_control1>; > }; > > cpu4: cpu@100 { > device_type = "cpu"; > compatible = "arm,cortex-a7"; > reg = <0x100>; > clock-frequency = <1000000000>; > cci-control-port = <&cci_control0>; > }; > > > Then you overwrite it with: > > &cpu0 { > device_type = "cpu"; > compatible = "arm,cortex-a7"; > reg = <0x100>; > clock-frequency = <1000000000>; > cci-control-port = <&cci_control0>; > }; > > &cpu4 { > device_type = "cpu"; > compatible = "arm,cortex-a15"; > reg = <0x0>; > clock-frequency = <1800000000>; > cci-control-port = <&cci_control1>; > }; > > > Don't you think this isn't the right way of solving problems? > > The DT overwrite feature isn't there to do such kind of stuff, though > it doesn't stop you from doing that. This is quite ugly, indeed, and it is getting uglier :)... but it does not violate the idea of DT to describe the hardware. Both hardware descriptions - the 5420 and overridden - are entirely correct... because the CPU ordering comes from booting sequence (actually code in IROM decides according to pulled up GPIO gpg2-1). > Either you should keep separate paths for both the SoCs, I like that idea. That makes it much more readable. Thanks for feedback! I will send a patch for that. > or can solve > it the way I suggested earlier. > > This came up because in the current series you are doing this: > > cpu0: cpu@0 { > compatible = "arm,cortex-a15"; > operating-points-v2 = <&cpu0_opp_table>; > }; > > cpu4: cpu@100 { > device_type = "cpu"; > compatible = "arm,cortex-a7"; > operating-points-v2 = <&cpu1_opp_table>; > }; > > > Then you overwrite it with: > > &cpu0 { > compatible = "arm,cortex-a7"; > operating-points-v2 = <&cpu1_opp_table>; > }; > > &cpu4 { > compatible = "arm,cortex-a15"; > operating-points-v2 = <&cpu0_opp_table>; > }; Yes, it is getting uglier with each change... Best regards, Krzysztof