Re: [linux-sunxi] [PATCH v2] arm64: allwinner: a64: Add A64-OLinuXino initial support

[Jagan Teki]

On Mon, Aug 14, 2017 at 1:26 PM, Chen-Yu Tsai <wens@xxxxxxxx> wrote:
> On Mon, Aug 14, 2017 at 3:34 PM, Jagan Teki <jagannadh.teki@xxxxxxxxx> wrote:
>> On Mon, Aug 14, 2017 at 12:38 PM, Chen-Yu Tsai <wens@xxxxxxxx> wrote:
>>> Hi,
>>>
>>> On Sun, Aug 13, 2017 at 1:54 AM, Jagan Teki <jagannadh.teki@xxxxxxxxx> wrote:
>>>> From: Jagan Teki <jagan@xxxxxxxxxxxxxxxxxxxx>
>>>>
>>>> OLimex A64-OLinuXino is an open-source hardware board
>>>> using the Allwinner A64 SOC.
>>>>
>>>> OLimex A64-OLinuXino has
>>>> - A64 Quad-core Cortex-A53 64bit
>>>> - 1GB or 2GB RAM DDR3L @ 672Mhz
>>>> - microSD slot and 4/8/16GB eMMC
>>>> - Debug TTL UART
>>>> - HDMI
>>>> - LCD
>>>> - IR receiver
>>>> - 5V DC power supply
>>>
>>> Have you tried out Ethernet?
>>
>> Not, tested yet. Will send separate patch.
>
> OK.
>
> [...]
>
>>>> +
>>>> +&reg_aldo2 {
>>>> +       regulator-always-on;
>>>> +       regulator-min-microvolt = <3300000>;
>>>> +       regulator-max-microvolt = <3300000>;
>>>
>>> Schematic says 1.8V?
>>
>> I saw ALD02 VCC-PL=3.3v on schematic.
>
> Ah. I see they changed it in a rev. B. Lets use 3.3V then.
>
>>>
>>>> +       regulator-name = "vcc-pl";
>>>> +};
>>>> +
>>>> +&reg_aldo3 {
>>>> +       regulator-always-on;
>>>> +       regulator-min-microvolt = <3000000>;
>>>> +       regulator-max-microvolt = <3000000>;
>>>> +       regulator-name = "vcc-pll-avcc";
>>>> +};
>>>> +
>>>> +&reg_dcdc1 {
>>>> +       regulator-always-on;
>>>> +       regulator-min-microvolt = <3300000>;
>>>> +       regulator-max-microvolt = <3300000>;
>>>> +       regulator-name = "vcc-3v3";
>>>> +};
>>>> +
>>>> +&reg_dcdc2 {
>>>> +       regulator-always-on;
>>>> +       regulator-min-microvolt = <1100000>;
>>>> +       regulator-max-microvolt = <1100000>;
>>>
>>> The SoC has a wider range than a fixed voltage for the CPUs.
>>
>> So, max 1.1v can't enough CPUs? thought similar behavior with pine64?
>
> The recommended operating conditions says 1.04 ~ 1.3 V for CPUx,
> while the typical voltage is 1.1V. The regulator constraints should
> match the datasheet, especially for power rails that are involved in
> DVFS.

power rails from datasheet[1] shows 0.5v ~ 1.3v am I not looking
updated details?

[1] http://files.pine64.org/doc/datasheet/pine64/AXP803_Datasheet_V1.0.pdf

thanks!
-- 
Jagan Teki
Free Software Engineer | www.openedev.com
U-Boot, Linux | Upstream Maintainer
Hyderabad, India.