commit a5630c1f303481bc711db65d6279ab5ee1969a31
parent a172180be8ccb836ab9f79f2c13c69b5aa26fd84
Author: Daniel Barlow <dan@telent.net>
Date: Sun, 26 Mar 2023 10:21:36 +0100
add cautionary note about flashing a running device
Diffstat:
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/doc/user.rst b/doc/user.rst
@@ -58,6 +58,12 @@ command. You need to locate the "firmware" partition, which you can do
with a combination of :command:`dmesg` output and the contents of
:file:`/proc/mtd`
+**Don't do this on a device that's running on the same flash partition
+as you're about to overwrite, otherwise you're likely to crash it. Use
+kexecboot (see "Updates to running devices" below) first to reboot
+into a RAM-based system.**
+
+
.. code-block:: console
<5>[ 0.469841] Creating 4 MTD partitions on "spi0.0":
@@ -87,7 +93,7 @@ and then connect to the device and run
.. code-block:: console
- flashcp firmware.bin /dev/mtd3
+ flashcp -v firmware.bin /dev/mtd3
@@ -108,7 +114,7 @@ Flashing from the boot monitor
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
If you are prepared to open the device and have a TTL serial adaptor
-or some kind to connect it to, you can probably flash it using U-Boot.
+of some kind to connect it to, you can probably flash it using U-Boot.
This is quite hardware-specific: please refer to the Developer Manual.