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Date:   Sat, 24 Jun 2023 09:30:13 +0200
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Subject: Re: [PATCH 2/2] arch: arm64: configs: Enable UBI and UBIFS
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To:     "Lee, Kah Jing" <kah.jing.lee@intel.com>,
        Dinh Nguyen <dinguyen@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>
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From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <PH0PR11MB567334A09B2D4A1D3DDC09F2CB20A@PH0PR11MB5673.namprd11.prod.outlook.com>
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On 24/06/2023 05:42, Lee, Kah Jing wrote:
>>>> So you miss init ramdisk.
>>> Currently we are using the bootargs to mount the rootfs from QSPI NOR
>> flash:
>>> [    0.000000] Kernel command line: earlycon panic=-1 ubi.mtd=1
>> root=ubi0:rootfs rootfstype=ubifs rw rootwait
>>> Is it possible to mount the ubifs rootfs with the ubifs=m config during boot?
>>
>> I think yes. rootfs devices are for example modules, so filesystem can be as
>> well.
> Was going through mtd ubifs page - http://www.linux-mtd.infradead.org/faq/ubifs.html
> Quoted: 'In order to mount UBIFS as the root file system, you have to compile 
> UBIFS into the kernel (instead of compiling it as a kernel module) and specify 
> proper kernel boot arguments and make the kernel mount UBIFS on boot.'

Why? Module loaded by initramfs would also understand cmdline arguments,
right?

Best regards,
Krzysztof