From mboxrd@z Thu Jan 1 00:00:00 1970 From: andre.przywara@arm.com (Andre Przywara) Date: Thu, 26 Jul 2018 01:35:26 +0100 Subject: [PATCH v2 12/18] arm64: dts: allwinner: a64: Olinuxino: fix DRAM voltage In-Reply-To: <20180726003532.18751-1-andre.przywara@arm.com> References: <20180726003532.18751-1-andre.przywara@arm.com> Message-ID: <20180726003532.18751-13-andre.przywara@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org The Olinuxino board uses DDR3L chips which are supposed to be driven with 1.35V. The reset default of the AXP is properly set to 1.36V. While technically the chips can also run at 1.5 volts, changing the voltage on the fly while booting Linux is asking for trouble. Also running at a lower voltage saves power. So fix the DCDC5 value to match the actual board design. Signed-off-by: Andre Przywara Tested-by: Martin Lucina --- arch/arm64/boot/dts/allwinner/sun50i-a64-olinuxino.dts | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64-olinuxino.dts b/arch/arm64/boot/dts/allwinner/sun50i-a64-olinuxino.dts index 3f531393eaee..b3f186434f36 100644 --- a/arch/arm64/boot/dts/allwinner/sun50i-a64-olinuxino.dts +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64-olinuxino.dts @@ -142,10 +142,14 @@ /* DCDC3 is polyphased with DCDC2 */ +/* + * The board uses DDR3L DRAM chips. 1.36V is the closest to the nominal + * 1.35V that the PMIC can drive. + */ ®_dcdc5 { regulator-always-on; - regulator-min-microvolt = <1500000>; - regulator-max-microvolt = <1500000>; + regulator-min-microvolt = <1360000>; + regulator-max-microvolt = <1360000>; regulator-name = "vcc-ddr3"; }; -- 2.14.4