From mboxrd@z Thu Jan 1 00:00:00 1970 From: arnd@arndb.de (Arnd Bergmann) Date: Mon, 10 Nov 2014 17:57:32 +0100 Subject: [PATCH] of/fdt: export fdt blob as /sys/firmware/fdt In-Reply-To: <1415638305-24463-1-git-send-email-ard.biesheuvel@linaro.org> References: <1415638305-24463-1-git-send-email-ard.biesheuvel@linaro.org> Message-ID: <3340387.dB5eK3mRnu@wuerfel> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Monday 10 November 2014 17:51:45 Ard Biesheuvel wrote: > Create a new /sys entry '/sys/firmware/fdt' to export the FDT blob > that was passed to the kernel by the bootloader. This allows userland > applications such as kexec to access the raw binary. > > The fact that this node does not reside under /sys/firmware/device-tree > is deliberate: FDT is also used on arm64 UEFI/ACPI systems to > communicate just the UEFI and ACPI entry points, but the FDT is never > unflattened and used to configure the system. > > Signed-off-by: Ard Biesheuvel Can you elaborate on the motivation? Initially the fdt format was introduced to make it easy to pass the information from /proc/device-tree to the next kernel for kexec. Are you interested in cases where this does not work? Arnd