Re: [PATCH v2 4/6] arm64: dts: qcom: Add base SM4450 QRD DTS

[Tengfei Fan <quic_tengfan@quicinc.com>]

在 7/27/2023 4:50 PM, Krzysztof Kozlowski 写道:
> On 27/07/2023 10:27, Tengfei Fan wrote:
>>
>>
>> 在 7/27/2023 2:56 PM, Krzysztof Kozlowski 写道:
>>> On 27/07/2023 04:35, Tengfei Fan wrote:
>>>> Add DTS for Qualcomm QRD platform which uses SM4450 SoC.
>>>>
>>>> Signed-off-by: Tengfei Fan <quic_tengfan@quicinc.com>
>>>> ---
>>>>    arch/arm64/boot/dts/qcom/Makefile       |  1 +
>>>>    arch/arm64/boot/dts/qcom/sm4450-qrd.dts | 18 ++++++++++++++++++
>>>>    2 files changed, 19 insertions(+)
>>>>    create mode 100644 arch/arm64/boot/dts/qcom/sm4450-qrd.dts
>>>>
>>>> diff --git a/arch/arm64/boot/dts/qcom/Makefile b/arch/arm64/boot/dts/qcom/Makefile
>>>> index 337abc4ceb17..db805d0929c8 100644
>>>> --- a/arch/arm64/boot/dts/qcom/Makefile
>>>> +++ b/arch/arm64/boot/dts/qcom/Makefile
>>>> @@ -186,6 +186,7 @@ dtb-$(CONFIG_ARCH_QCOM)	+= sdm850-lenovo-yoga-c630.dtb
>>>>    dtb-$(CONFIG_ARCH_QCOM)	+= sdm850-samsung-w737.dtb
>>>>    dtb-$(CONFIG_ARCH_QCOM)	+= sdx75-idp.dtb
>>>>    dtb-$(CONFIG_ARCH_QCOM)	+= sm4250-oneplus-billie2.dtb
>>>> +dtb-$(CONFIG_ARCH_QCOM)	+= sm4450-qrd.dtb
>>>>    dtb-$(CONFIG_ARCH_QCOM)	+= sm6115-fxtec-pro1x.dtb
>>>>    dtb-$(CONFIG_ARCH_QCOM)	+= sm6115p-lenovo-j606f.dtb
>>>>    dtb-$(CONFIG_ARCH_QCOM)	+= sm6125-sony-xperia-seine-pdx201.dtb
>>>> diff --git a/arch/arm64/boot/dts/qcom/sm4450-qrd.dts b/arch/arm64/boot/dts/qcom/sm4450-qrd.dts
>>>> new file mode 100644
>>>> index 000000000000..04ad1dd4285a
>>>> --- /dev/null
>>>> +++ b/arch/arm64/boot/dts/qcom/sm4450-qrd.dts
>>>> @@ -0,0 +1,18 @@
>>>> +// SPDX-License-Identifier: BSD-3-Clause
>>>> +/*
>>>> + * Copyright (c) 2023, Qualcomm Innovation Center, Inc. All rights reserved.
>>>> + */
>>>> +
>>>> +/dts-v1/;
>>>> +
>>>> +#include "sm4450.dtsi"
>>>> +/ {
>>>> +	model = "Qualcomm Technologies, Inc. SM4450 QRD";
>>>> +	compatible = "qcom,sm4450-qrd", "qcom,sm4450";
>>>> +
>>>> +	aliases { };
>>>> +
>>>> +	chosen {
>>>> +		bootargs = "console=hvc0 earlycon=hvc0 hvc_dcc.enable=1 cpuidle.off=1";
>>>
>>> No earlycon, no hvc.enable (there is no such parameter), no cpuidle.off
>>> (again don't add fake stuff). So the only suitable argument is console,
>>> but this should be actually used via stdout path, although it seems
>>> there is no device node for such usage?
>> Hi Krzysztof,
>> Checked upstream linux kernel code, there is not "hvc_dcc.enable", but
>> have other parameters, like earlycon, cpuidle.off.
>> Do you mean we should not set "earlycon=hvc0 cpuidle.off=1" parameters,
> 
> Of course not. Why production code would have earlycon? This is debug
> argument, not suitable for each user of this DTS.
> 
> cpuidle.off is neither explained nor needed. Otherwise please add a
> comment why this is part of hardware description.
> 
>> right? only need: bootargs = "console=hvc0" ?
> 
> You should use stdout-path if possible. If not, then only console.
> 
> Best regards,
> Krzysztof
> 
Sure, will update this patch for have right boorargs parameter.

-- 
Thx and BRs,
Tengfei Fan