* Avoid trying to boot non-existing kernel image in fail-over case
The A/B update system automatically switches to the other boot slot when
booting fails. However, in a fresh installation, only boot slot A
exists. If booting fails three times (e.g. if somebody plugs out power
before the slot can be marked as good), then the system switches to boot
slot B which does not contain a kernel image yet. Avoid trying to boot
the non-existing kernel image.
With this change, if slot B is empty U-Boot will restore both slots to 3
attempts and retry booting from slot A on next reboot:
```
Trying to boot slot B, 2 attempts remaining. Loading kernel ...
** Unrecognized filesystem type **
No valid slot found, resetting tries to 3
storing env...
```
Co-authored-by: Pascal Vizeli <pascal.vizeli@syshack.ch>
* Remove rk3288-xt-q8l-v10.dts related patches
We only support ASUS Tinker Board, so no need for those patches.
* Remove unnecessary patches and rebase some for Tinker Board S
Some patches only apply to the Tinker Board device tree. Rebase them to
apply to the dtsi file so they apply for both boards, the Tinker Board
and the Tinker Board S board.
* Fix Tinker Board S (eMMC) boot (#650)
Use Tinker Board S U-Boot configuration which is capable to boot from
eMMC as well as from SD card.
Note that this makes U-Boot always claiming to run on Tinker Board S:
..
Model: Rockchip RK3288 Asus Tinker Board S
..
It seems that there is no generic Tinker Board configuration. However,
Tinker Board S configuration really seems to work well with Tinker Board
as well, so just use it.
Also today the U-Boot Makefile seems to generate a working idbloader.img
already. Drop our special handling.
* Use Tinker Board S device tree if booting from eMMC for Linux
Instead of patching the Tinker Board device tree, select the device tree
based on what device we are booting from.
Note: This boots the non-S device tree when booting a Tinker Board S
from SD card! But there is no reliable detection otherwise, so let's
just live with that fact.
* Document how to use our U-Boot to flash eMMC
