Messages in this thread | ![/](/images/icornerl.gif) | | From | "Lee, Kah Jing" <> | Subject | RE: [PATCH 2/2] arch: arm64: configs: Enable UBI and UBIFS | Date | Tue, 27 Jun 2023 03:40:06 +0000 |
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> -----Original Message----- > From: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> > Sent: Monday, 26 June, 2023 4:39 PM > 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> > Cc: linux-kernel@vger.kernel.org > Subject: Re: [PATCH 2/2] arch: arm64: configs: Enable UBI and UBIFS > > On 26/06/2023 06:16, Lee, Kah Jing wrote: > >> -----Original Message----- > >> From: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> > >> Sent: Saturday, 24 June, 2023 3:30 PM > >> 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> > >> Cc: linux-kernel@vger.kernel.org > >> Subject: Re: [PATCH 2/2] arch: arm64: configs: Enable UBI and UBIFS > >> > >> 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? > > The suggestion is to use initramfs for rootfs -> remount UBIFS as chroot? > > The concern is additional initrd image and steps to store in the > > limited NOR flash (256MB, Boot data + Uboot - ~66MB, UBIFS image - > > ~88MB, kernel.itb - ~10MB = 164MB). > > With the mounting Rootfs from UBIFS volume, we can skip the initrd > > step, and save some space for the user operations. > > Let me know if I understands that correctly. > > arm64 defconfig creates huge development config for all platforms, so why > would you ever use it in resource-constrained system? It would barely fit. > defconfig modules take 50 MB alone and you don't need most of them. > > I think you misunderstood the purpose of this defconfig and now try to apply > some arguments for different use cases. Understood the point. In this case, I would drop this defconfig patch, and document it for customers to enable through menuconfig.
Will proceed to send the v3 for only dts changes. Thanks for the time. > > Best regards, > Krzysztof
Regards, Lee, Kah Jing
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