From mboxrd@z Thu Jan 1 00:00:00 1970 From: Maxime Ripard Subject: Re: [PATCH 1/4] arm64: dts: allwinner: h6: orangepi: Add CPU supply regulator Date: Thu, 14 Feb 2019 15:35:55 +0100 Message-ID: <20190214143555.4jago2wp4vojz7rk@flea> References: <20190214130910.9201-1-tiny.windzz@gmail.com> <20190214130910.9201-2-tiny.windzz@gmail.com> <20190214134617.b44pa7onf3brmhhj@flea> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8BIT Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Frank Lee Cc: Chen-Yu Tsai , robh+dt@kernel.org, mark.rutland@arm.com, Linux ARM , devicetree@vger.kernel.org, Linux Kernel Mailing List List-Id: devicetree@vger.kernel.org Hi, On Thu, Feb 14, 2019 at 10:07:02PM +0800, Frank Lee wrote: > On Thu, Feb 14, 2019 at 9:46 PM Maxime Ripard wrote: > > Thanks for your patches > > > > On Thu, Feb 14, 2019 at 08:09:07AM -0500, Yangtao Li wrote: > > > The original orangepi use the dcdca to supply the CPU cores. According > > > to the axp805 spec, the range of dcdca is 0.6 to 1.1v, 1.12 to 1.52v. > > > In order to support more CPU frequency, slightly increase the voltage > > > maximum and minimum. > > > > > > Signed-off-by: Yangtao Li > > > --- > > > arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi.dtsi | 8 ++++++-- > > > 1 file changed, 6 insertions(+), 2 deletions(-) > > > > > > diff --git a/arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi.dtsi b/arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi.dtsi > > > index b2526dac2fcf..e7aebaf91ede 100644 > > > --- a/arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi.dtsi > > > +++ b/arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi.dtsi > > > @@ -159,8 +159,8 @@ > > > > > > reg_dcdca: dcdca { > > > regulator-always-on; > > > - regulator-min-microvolt = <810000>; > > > - regulator-max-microvolt = <1080000>; > > > + regulator-min-microvolt = <800000>; > > > + regulator-max-microvolt = <1160000>; > > > > This violates the minimum and maximum recommended voltages in the H6 > > datasheet. Could you clarify why you are doing so (ideally in the > > commit log)? > > In fact, in sunxi's sdk, the actual minimum and maximum voltage of the > cpu is smaller or larger than the datasheet. > > For some better quality ic, the minimum voltage can be smaller. > For some poor quality ic, the maximum voltage needs to be increased a little. Ok, that should definitely be part of the commit log then :) Thanks! Maxime -- Maxime Ripard, Bootlin Embedded Linux and Kernel engineering https://bootlin.com