1From: Mauro Salvini <m.salvini@koansoftware.com> 2To: u-boot@lists.denx.de 3Subject: [PATCH] rpi: always set fdt_addr with firmware-provided FDT address 4Date: Wed, 12 May 2021 14:39:45 +0200 [thread overview] 5Message-ID: <20210512123945.25649-1-m.salvini@koansoftware.com> (raw) 6 7Raspberry firmware prepares the FDT blob in memory at an address 8that depends on both the memory size and the blob size [1]. 9After commit ade243a211d6 ("rpi: passthrough of the firmware provided FDT 10blob") this FDT is passed to kernel through fdt_addr environment variable, 11handled in set_fdt_addr() function in board file. 12 13When u-boot environment is persistently saved, if a change happens 14in loaded FDT (e.g. for a new overlay applied), firmware produces a FDT 15address different from the saved one, but u-boot still use the saved 16one because set_fdt_addr() function does not overwrite the fdt_addr 17variable. So, for example, if there is a script that uses fdt commands for 18e.g. manipulate the bootargs, boot hangs with error 19 20libfdt fdt_check_header(): FDT_ERR_BADMAGIC 21 22Removing the fdt_addr variable in saved environment allows to boot. 23 24With this patch set_fdt_addr() function always overwrite fdt_addr value. 25 26[1] https://www.raspberrypi.org/forums//viewtopic.php?f=107&t=134018 27 28Signed-off-by: Mauro Salvini <m.salvini@koansoftware.com> 29Cc: C?dric Schieli <cschieli@gmail.com> 30Cc: Matthias Brugger <mbrugger@suse.com> 31--- 32 board/raspberrypi/rpi/rpi.c | 3 --- 33 1 file changed, 3 deletions(-) 34 35diff --git a/board/raspberrypi/rpi/rpi.c b/board/raspberrypi/rpi/rpi.c 36index df52a4689f..611013471e 100644 37--- a/board/raspberrypi/rpi/rpi.c 38+++ b/board/raspberrypi/rpi/rpi.c 39@@ -318,9 +318,6 @@ static void set_fdtfile(void) 40 */ 41 static void set_fdt_addr(void) 42 { 43- if (env_get("fdt_addr")) 44- return; 45- 46 if (fdt_magic(fw_dtb_pointer) != FDT_MAGIC) 47 return; 48 49-- 502.17.1