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Thread-Topic: Running/building an 32 bits kernel on A53 CPU? 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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, 2021-10-29 at 10:32 +0000, Joakim Tjernlund wrote: > On Fri, 2021-10-29 at 11:09 +0100, Catalin Marinas wrote: > > On Fri, Oct 29, 2021 at 08:27:35AM +0000, Joakim Tjernlund wrote: > > > In order to reduce RAM usage we are wondering if running an 32 bits > > > kernel on ARM A53 CPU is a good idea? > > > > No. Really. > > > > What's the RAM size on your SoC? > > 32MB + 4MB SRAM > > > > > > Is it possible to build such a kernel? If so, how to go about it? > > > Should one use ARCH=arm and a 32 bits toolchain or > > > ARCH=arm64 and 64 bits toolchain and adding 32 bits compile options? > > > > If you want a 32-bit kernel, you'd have to use ARCH=arm and a 32-bit > > toolchain. This would give you an ARMv7 kernel that can run on ARMv8 > > hardware. But you'd miss errata workarounds for example and any other > > features that come with ARMv8. Anything else you can think of why 32 bits kernel is a bad idea? I do wonder why 64 bits A53 enforces SMP? I only have one core in my HW(custom ASIC) Jocke > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel