于 2018年4月30日 GMT+08:00 下午5:47:35, Andre Przywara <andre.przywara@xxxxxxx> 写到: >Hi Icenowy, > >On 27/04/18 08:12, Icenowy Zheng wrote: >> >> >> 于 2018年4月27日 GMT+08:00 上午12:46:26, Andre Przywara ><andre.przywara@xxxxxxx> 写到: >>> Hi, >>> >>> On 26/04/18 15:07, Icenowy Zheng wrote: >>>> The Pine H64 board have a MicroSD slot connected to MMC0 controller >>> of >>>> the H6 SoC and a eMMC slot connected to MMC2. >>>> >>>> Enable them in the device tree. >>>> >>>> Signed-off-by: Icenowy Zheng <icenowy@xxxxxxx> >>>> --- >>>> .../boot/dts/allwinner/sun50i-h6-pine-h64.dts | 32 >>> ++++++++++++++++++++++ >>>> 1 file changed, 32 insertions(+) >>>> >>>> diff --git a/arch/arm64/boot/dts/allwinner/sun50i-h6-pine-h64.dts >>> b/arch/arm64/boot/dts/allwinner/sun50i-h6-pine-h64.dts >>>> index d36de5eb81f3..78b1cd54687c 100644 >>>> --- a/arch/arm64/boot/dts/allwinner/sun50i-h6-pine-h64.dts >>>> +++ b/arch/arm64/boot/dts/allwinner/sun50i-h6-pine-h64.dts >>>> @@ -20,6 +20,38 @@ >>>> chosen { >>>> stdout-path = "serial0:115200n8"; >>>> }; >>>> + >>>> + reg_vcc3v3: vcc3v3 { >>>> + compatible = "regulator-fixed"; >>>> + regulator-name = "vcc3v3"; >>>> + regulator-min-microvolt = <3300000>; >>>> + regulator-max-microvolt = <3300000>; >>>> + }; >>>> + >>>> + reg_vcc1v8: vcc1v8 { >>>> + compatible = "regulator-fixed"; >>>> + regulator-name = "vcc1v8"; >>>> + regulator-min-microvolt = <1800000>; >>>> + regulator-max-microvolt = <1800000>; >>>> + }; >>>> +}; >>>> + >>>> +&mmc0 { >>>> + pinctrl-names = "default"; >>>> + pinctrl-0 = <&mmc0_pins>; >>>> + vmmc-supply = <®_vcc3v3>; >>> >>> So this is actually CLDO1 on the AXP, correct? >> >> I remember it's coupled between two LDOs, to provide enough power. >> >>> >>> >>>> + cd-gpios = <&pio 5 6 GPIO_ACTIVE_LOW>; >>>> + status = "okay"; >>>> +}; >>>> + >>>> +&mmc2 { >>>> + pinctrl-names = "default"; >>>> + pinctrl-0 = <&mmc2_pins>; >>>> + vmmc-supply = <®_vcc3v3>; >>>> + vqmmc-supply = <®_vcc1v8>; >>> >>> And this is BLDO2? >> >> Yes. >> >>> >>> I am just asking because I want to avoid running into the same >problem >>> as with the A64 before: that future DTs become incompatible with >older >>> kernels, because we change the power supply to point to the AXP >>> regulators, which this kernel does not support yet. >> >> The answer is just not to keep this compatibility, as it's not >> supported option to update DT without updating kernel. > >Well, I recognise that statement.. ;-) and I understand that it's far >easier to handle it this way. But: >- Which .dtb are we going to write into the SPI flash? An older one, >which covers all kernels, but lacks features? Or a newer one, which >limits the bootable kernels to recent versions? >- Which DT are we going to give to EFI applications? >- Which DT are the BSDs suspected to take? They don't ship their own >DTs >(which is good!). > >So I understand that "shipping the DT with the kernel" is the old >(embedded!) way of doing things, but I really believe we should stop >relying on this and try to come up with backwards compatible DTs, which >live in the firmware and get updated there. Because this is what the >distros seem to expect from ARM64 boards these days. I think in this way we should change the way to submit patches -- let DT binding patch be merged when it's ready, and do not wait for driver. > >> P.S. I think the DT will update twice on the kernel side, the >> first time keep reg_vcc3v3 (as it's coupled) but use real >> regulator for reg_vcc1v8, the second time use the real >> coupled regulator for reg_vcc3v3. >> >>> >>> It looks like there are more users of those power rails, so we could >>> keep those supplies connected to these fixed regulators here, even >with >>> AXP-805 support in the kernel. >> >> It's not a good choice. >> >>> >>> Or we keep this back until we get proper AXP support in the kernel? >I >>> guess it's quite close to the existing PMICs, so it might be more a >>> copy&paste exercise to support the AXP-805? >> >> It's not a reason to keep it back. > >So I compared the manuals of the AXP806 and the AXP805, the register >interface looks identical to me. I only have a (somewhat) Chinese >version of the AXP806 manual, so couldn't really find the difference >between the two. Do you know more about it? Is it just maybe the >packaging and the electrical properties (like max current supported)? > >If the I2C register interface is really the same, we could just add the >DT nodes for the regulator and be done. They're the same. My following patchset adds AXP805 compatible just to use AXP806 code. I have asked Wink and the answer is that they have only preset difference. > >Cheers, >Andre. > >> >>> >>> But apart from this this looks correct to me. >>> >>> Cheers, >>> Andre. >>> >>>> + non-removable; >>>> + cap-mmc-hw-reset; >>>> + status = "okay"; >>>> }; >>>> >>>> &uart0 { >>>> -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html