From 12a3e1ada06c702c403cf1eebb063ef7a34688cd Mon Sep 17 00:00:00 2001 From: Dzmitry Sankouski Date: Tue, 22 Feb 2022 21:49:52 +0300 Subject: arm: init: save previous bootloader data When u-boot is used as a chain-loaded bootloader (replacing OS kernel), previous bootloader leaves data in RAM, that can be reused. For example, on recent arm linux system, when chainloading u-boot, there are initramfs and fdt in RAM prepared for OS booting. Initramfs may be modified to store u-boot's payload, thus providing the ability to use chainloaded u-boot to boot OS without any storage support. Two config options added: - SAVE_PREV_BL_INITRAMFS_START_ADDR saves initramfs start address to 'prevbl_initrd_start_addr' environment variable - SAVE_PREV_BL_FDT_ADDR saves fdt address to 'prevbl_fdt_addr' environment variable Signed-off-by: Dzmitry Sankouski Cc: Tom Rini --- include/init.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'include') diff --git a/include/init.h b/include/init.h index 74496500d29..7b8f62c1218 100644 --- a/include/init.h +++ b/include/init.h @@ -155,6 +155,19 @@ int arch_setup_bdinfo(void); */ int setup_bdinfo(void); +#if defined(CONFIG_SAVE_PREV_BL_INITRAMFS_START_ADDR) || \ +defined(CONFIG_SAVE_PREV_BL_FDT_ADDR) +/** + * save_prev_bl_data - Save prev bl data in env vars. + * + * When u-boot is chain-loaded, save previous bootloader data, + * like initramfs address to environment variables. + * + * Return: 0 if ok; -ENODATA on error + */ +int save_prev_bl_data(void); +#endif + /** * cpu_secondary_init_r() - CPU-specific secondary initialization * -- cgit v1.2.3