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Date: Thu, 21 Dec 2023 22:25:04 +0000
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Subject: Re: [PATCH v5 00/22] Add support for the Mobileye EyeQ5 SoC
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To: Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
 Gregory CLEMENT <gregory.clement@bootlin.com>
Cc: Paul Burton <paulburton@kernel.org>, linux-mips@vger.kernel.org,
 Rob Herring <robh+dt@kernel.org>,
 Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
 devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
 Vladimir Kondratiev <vladimir.kondratiev@mobileye.com>,
 Tawfik Bayouk <tawfik.bayouk@mobileye.com>,
 Alexandre Belloni <alexandre.belloni@bootlin.com>,
 =?UTF-8?Q?Th=C3=A9o_Lebrun?= <theo.lebrun@bootlin.com>,
 Thomas Petazzoni <thomas.petazzoni@bootlin.com>
References: <20231212163459.1923041-1-gregory.clement@bootlin.com>
 <878r5vctdg.fsf@BL-laptop> <ZYNhbQjMbAH6I0kI@alpha.franken.de>
 <87frzwasxo.fsf@BL-laptop> <ZYRR7zIZax7yUgsZ@alpha.franken.de>
From: Jiaxun Yang <jiaxun.yang@flygoat.com>
In-Reply-To: <ZYRR7zIZax7yUgsZ@alpha.franken.de>
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在 2023/12/21 14:55, Thomas Bogendoerfer 写道:
> On Thu, Dec 21, 2023 at 08:57:55AM +0100, Gregory CLEMENT wrote:
>> I do not oppose the addition of a new platform, even though, like
>> Jiaxun, I would prefer to avoid duplicating code. The only thing
>> preventing the use of the same kernel for EyeQ5 and other platforms is
>> the starting address.
> there shouldn't be code duplication.
>
> My rough idea would be something like
>
> diff --git a/arch/mips/Kbuild b/arch/mips/Kbuild
> index af2967bffb73..d683993ed331 100644
> --- a/arch/mips/Kbuild
> +++ b/arch/mips/Kbuild
> @@ -17,6 +17,7 @@ obj- := $(platform-y)
>   # mips object files
>   # The object files are linked as core-y files would be linked
>   
> +obj-y += generic/
>   obj-y += kernel/
>   obj-y += mm/
>   obj-y += net/
> diff --git a/arch/mips/generic/Makefile b/arch/mips/generic/Makefile
> index e37a59bae0a6..56011d738441 100644
> --- a/arch/mips/generic/Makefile
> +++ b/arch/mips/generic/Makefile
> @@ -4,9 +4,9 @@
>   # Author: Paul Burton <paul.burton@mips.com>
>   #
>   
> -obj-y += init.o
> -obj-y += irq.o
> -obj-y += proc.o
> +obj-$(CONFIG_MACH_GENERIC_CORE) += init.o
> +obj-$(CONFIG_MACH_GENERIC_CORE) += irq.o
> +obj-$(CONFIG_MACH_GENERIC_CORE) += proc.o
>   
>   obj-$(CONFIG_YAMON_DT_SHIM)            += yamon-dt.o
>   obj-$(CONFIG_LEGACY_BOARD_SEAD3)       += board-sead3.o
>
> so everyboady needing these parts of a generic kernel is able
> to take it.
>
>> Therefore, if it were possible to have a relocatable kernel, this
>> issue would disappear.
> yes. There is support for relocatable kernel, so what are we missing
> there ?

It does not handle 64 bit relocations currently.
I tried to look into it and it's not a easy fix.

Thanks
- Jiaxun
> Thomas.
>