Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751129AbdGZHga (ORCPT ); Wed, 26 Jul 2017 03:36:30 -0400 Received: from hermes.aosc.io ([199.195.250.187]:52642 "EHLO hermes.aosc.io" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750813AbdGZHg2 (ORCPT ); Wed, 26 Jul 2017 03:36:28 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Date: Wed, 26 Jul 2017 15:36:27 +0800 From: icenowy@aosc.io To: wens@csie.org Cc: Liam Girdwood , Mark Brown , Maxime Ripard , linux-kernel , devicetree , linux-arm-kernel , linux-clk , "open list:THERMAL" , linux-sunxi , Ondrej Jirman Subject: Re: [linux-sunxi] [PATCH 10/10] ARM: dts: sun8i: Add SY8106A regulator to Orange Pi PC In-Reply-To: References: <20170723102749.17323-1-icenowy@aosc.io> <20170723102749.17323-11-icenowy@aosc.io> <25C8A89C-8495-4787-934C-8E9667CD70BF@aosc.io> Message-ID: <82507f40a1ddba8517cf09f51d3afa33@aosc.io> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2904 Lines: 102 在 2017-07-26 15:30，Chen-Yu Tsai 写道： > On Wed, Jul 26, 2017 at 3:16 PM, Icenowy Zheng wrote: >> >> >> 于 2017年7月26日 GMT+08:00 下午3:08:06, Chen-Yu Tsai 写到: >>> On Sun, Jul 23, 2017 at 6:27 PM, Icenowy Zheng >>> wrote: >>>> From: Ondrej Jirman >>>> >>>> Add SY8106A regulator to r_i2c bus and enable the r_i2c bus on >>>> Orange Pi PC, then set the power supply of the ARM cores to this >>>> regulator, in order to enable DVFS. >>>> >>>> Signed-off-by: Ondrej Jirman >>>> [Icenowy: Enable DVFS in this patch, slight changes and change >>>> commit >>>> message] >>>> Signed-off-by: Icenowy Zheng >>>> --- >>>> arch/arm/boot/dts/sun8i-h3-orangepi-pc.dts | 19 +++++++++++++++++++ >>>> 1 file changed, 19 insertions(+) >>>> >>>> diff --git a/arch/arm/boot/dts/sun8i-h3-orangepi-pc.dts >>> b/arch/arm/boot/dts/sun8i-h3-orangepi-pc.dts >>>> index 998b60f8d295..d855f8b6254e 100644 >>>> --- a/arch/arm/boot/dts/sun8i-h3-orangepi-pc.dts >>>> +++ b/arch/arm/boot/dts/sun8i-h3-orangepi-pc.dts >>>> @@ -98,6 +98,10 @@ >>>> status = "okay"; >>>> }; >>>> >>>> +&cpu0 { >>>> + cpu-supply = <®_sy8106a>; >>>> +}; >>>> + >>>> &ehci0 { >>>> status = "okay"; >>>> }; >>>> @@ -160,6 +164,21 @@ >>>> }; >>>> }; >>>> >>>> +&r_i2c { >>>> + status = "okay"; >>>> + >>>> + reg_sy8106a: regulator@65 { >>>> + compatible = "silergy,sy8106a"; >>>> + reg = <0x65>; >>>> + regulator-name = "vdd-cpux"; >>>> + regulator-min-microvolt = <1000000>; >>> >>> According to the H3 datasheet, the minimum voltage is 1.1V, not 1V. >> >> But the Armbian OPP table for H3 contains several >> OPP under 1.1V... > > Can you provide a link? > > If Armbian users have actually field tested this (a big if), > then I would like to see some evidence of the SoC running > stably at those OPPs with those lower voltages under full load. See [1]. [1] https://github.com/armbian/build/blob/master/config/fex/orangepipc.fex#L736 > > Even then you should still leave a note describing why we allow > voltages below the recommended range. > > ChenYu > >> >>> >>> Otherwse >>> >>>> + regulator-max-microvolt = <1400000>; >>>> + regulator-ramp-delay = <200>; >>> >>> Is this an actual constraint of the SoC? Or is it a characteristic >>> of the regulator? If it is the latter, it belongs in the driver. >>> AFAIK the regulator supports varying the ramp delay (slew rate). I don't know... Maybe I should ask Ondrej? >>> >>> ChenYu >>> >>>> + regulator-boot-on; >>>> + regulator-always-on; >>>> + }; >>>> +}; >>>> + >>>> &r_pio { >>>> leds_r_opc: led_pins@0 { >>>> pins = "PL10"; >>>> -- >>>> 2.13.0 >>>>