Message-ID: <1bd61fa7-cd0e-e198-9cee-7485eacbe685@quicinc.com>
Date:   Mon, 13 Mar 2023 21:48:39 -0700
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Subject: Re: [PATCH] arm64: dts: qcom: sa8775p: add symbols to dtb
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To:     Konrad Dybcio <konrad.dybcio@linaro.org>,
        Eric Chanudet <echanude@redhat.com>,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>
CC:     <linux-arm-msm@vger.kernel.org>, <devicetree@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>
References: <20230309233945.1199358-1-echanude@redhat.com>
 <43c11038-91d5-cbfd-7349-06fcd61a0661@linaro.org>
From:   Prasad Sodagudi <quic_psodagud@quicinc.com>
In-Reply-To: <43c11038-91d5-cbfd-7349-06fcd61a0661@linaro.org>
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On 3/9/2023 3:47 PM, Konrad Dybcio wrote:
> 
> 
> On 10.03.2023 00:39, Eric Chanudet wrote:
>> ABL uses the __symbols__ section to process the DTB before passing it
>> forward. Without it, the bootstrap is interrupted.
>>
>> Signed-off-by: Eric Chanudet <echanude@redhat.com>
>> ---
> Fix your ABL.
Hi Konrad,

Apps boot-loader need __symbols__ for dynamic overlay operation. 
Qualcomm firmware passes an overlay file to apps boot-loader to overlay 
some of the nodes based on firmware configuration. Without __symbols__ 
apps boot-loader is not able to overlay.

Qualcomm hypervisor/gunyah would like to overlay arch timer node with 
always-on property, So adding __symbols__ helps boot-loader to overlay.

I think, commit text is misleading here and I will request Eric to fix 
the commit text.

-Thanks, Prasad

> 
> Konrad
>> Depends on initial sa8775p-ride.dts:
>> https://lore.kernel.org/all/20230214092713.211054-3-brgl@bgdev.pl/
>>
>>   arch/arm64/boot/dts/qcom/Makefile | 4 ++++
>>   1 file changed, 4 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/qcom/Makefile b/arch/arm64/boot/dts/qcom/Makefile
>> index b63cd1861e68..72e85ab31d74 100644
>> --- a/arch/arm64/boot/dts/qcom/Makefile
>> +++ b/arch/arm64/boot/dts/qcom/Makefile
>> @@ -1,4 +1,8 @@
>>   # SPDX-License-Identifier: GPL-2.0
>> +
>> +# Enable support for device-tree overlays required on sa8775p-ride.
>> +DTC_FLAGS_sa8775p-ride := -@
>> +
>>   dtb-$(CONFIG_ARCH_QCOM)	+= apq8016-sbc.dtb
>>   dtb-$(CONFIG_ARCH_QCOM)	+= apq8094-sony-xperia-kitakami-karin_windy.dtb
>>   dtb-$(CONFIG_ARCH_QCOM)	+= apq8096-db820c.dtb
> 
>