fw_env: autodetect NAND erase size and env sectors
As already done for NOR chips, if device ESIZE and ENVSECTORS static
configurations are both zero, then autodetect them at runtime.
Cc: Joe Hershberger <joe.hershberger@ni.com>
cc: Stefan Agner <stefan@agner.ch>
cc: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Signed-off-by: Anthony Loiseau <anthony.loiseau@allcircuits.com>
diff --git a/tools/env/README b/tools/env/README
index 480a893..b8c6a7e 100644
--- a/tools/env/README
+++ b/tools/env/README
@@ -58,6 +58,9 @@
this environment instance. On NAND this is used to limit the range
within which bad blocks are skipped, on NOR it is not used.
+If DEVICEx_ESIZE and DEVICEx_ENVSECTORS are both zero, then a runtime
+detection is attempted for NOR and NAND mtd types.
+
To prevent losing changes to the environment and to prevent confusing the MTD
drivers, a lock file at /run/fw_printenv.lock is used to serialize access
to the environment.