Hi Matthias
On 15/09/21 13:16, mbrugger at suse.com (Matthias Brugger) wrote:
Hi Mauro,
On 07/06/2021 11:27, Mauro Salvini wrote:
On 12/05/21 14:39, Mauro Salvini wrote:
Raspberry firmware prepares the FDT blob in memory at an address
that depends on both the memory size and the blob size [1].
After commit ade243a211d6 ("rpi: passthrough of the firmware provided FDT
blob") this FDT is passed to kernel through fdt_addr environment variable,
handled in set_fdt_addr() function in board file.
When u-boot environment is persistently saved, if a change happens
in loaded FDT (e.g. for a new overlay applied), firmware produces a FDT
address different from the saved one, but u-boot still use the saved
one because set_fdt_addr() function does not overwrite the fdt_addr
variable. So, for example, if there is a script that uses fdt commands for
e.g. manipulate the bootargs, boot hangs with error
libfdt fdt_check_header(): FDT_ERR_BADMAGIC
Removing the fdt_addr variable in saved environment allows to boot.
With this patch set_fdt_addr() function always overwrite fdt_addr value.
[1] https://www.raspberrypi.org/forums//viewtopic.php?f=107&t=134018
First of all sorry for the very late reply.
I'm hesitant to apply this patch, basically because it can break other setups
where people load a custom DTB to fdt_addr.
I wonder why you can't erase fdt_addr from your persistent storage. There is a
command called eraseenv that should to the job.
Sorry me too for the late reply.
So your suggestion is to erase the fdt_addr variable from the
environment each time one needs to "refresh" it (one example could be
the situation that I ponted out).
Yes, this could be the solution, but the need to delete the fdt_addr
variable when e.g. one changes the dtb loaded by rpi firmware should be
documented somewhere.
Thanks, regards
Mauro
Regards,
Matthias
Signed-off-by: Mauro Salvini <m.salvini at koansoftware.com>
Cc: C?dric Schieli <cschieli at gmail.com>
Cc: Matthias Brugger <mbrugger at suse.com>
---
? board/raspberrypi/rpi/rpi.c | 3 ---
? 1 file changed, 3 deletions(-)
diff --git a/board/raspberrypi/rpi/rpi.c b/board/raspberrypi/rpi/rpi.c
index df52a4689f..611013471e 100644
--- a/board/raspberrypi/rpi/rpi.c
+++ b/board/raspberrypi/rpi/rpi.c
@@ -318,9 +318,6 @@ static void set_fdtfile(void)
?? */
? static void set_fdt_addr(void)
? {
-??? if (env_get("fdt_addr"))
-??????? return;
-
????? if (fdt_magic(fw_dtb_pointer) != FDT_MAGIC)
????????? return;
Hi all,
kind ping.
Regards
--
Mauro Salvini | KOAN sas | Bergamo - Italia
embedded software engineering
Phone: +39 035-255235
http://KoanSoftware.com
