From 08d53aa58cb162e65e25dbe31d28438657cb8e33 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Fri, 14 Nov 2014 18:05:35 +0100 Subject: of/fdt: export fdt blob as /sys/firmware/fdt 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. A CRC32 checksum is calculated over the entire FDT blob, and verified at late_initcall time. The sysfs entry is instantiated only if the checksum is valid, i.e., if the FDT blob has not been modified in the mean time. Otherwise, a warning is printed. Signed-off-by: Ard Biesheuvel Signed-off-by: Grant Likely --- drivers/of/Kconfig | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/of/Kconfig') diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig index be16ce2ffd69..fbe8f8d418f7 100644 --- a/drivers/of/Kconfig +++ b/drivers/of/Kconfig @@ -23,6 +23,7 @@ config OF_FLATTREE bool select DTC select LIBFDT + select CRC32 config OF_EARLY_FLATTREE bool -- cgit v1.2.3