board/aarch64/r2s: add README for the NanoPi R2S board

Fixes #275 Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
2026-07-30 04:33:00 +02:00 · 2024-08-16 16:47:28 +02:00
parent 094a1ac4f1
commit 9b6dedbe08
2 changed files with 104 additions and 0 deletions
@@ -3,5 +3,7 @@ aarch64

 Board Specific Documentation
 ----------------------------
+
 - [Marvell CN9130-CRB](cn9130-crb/)
 - [Microchip SparX-5i PCB135 (eMMC)](sparx5-pcb135/)
+- [NanoPi R2S](r2s/)
@@ -0,0 +1,102 @@
+FriendlyELC NanoPi R2S
+======================
+
+The [NanoPi R2S][1] is a very low-cost 64-bit ARM min router, powered by
+the Rockchip RK3328, quad-core Cortex-A53.
+
+The R2S does not have any onboard eMMC, so the only way to boot Infix on
+it is using and SD card.
+
+
+How to Build
+------------
+
+```
+$ make r2s_defconfig
+$ make
+```
+
+Once the build has finished you will have `output/images/sdcard.img`
+which you can flash to an SD card.
+
+```
+$ sudo dd if=output/images/sdcard.img of=/dev/mmcblk0 bs=1M status=progress oflag=direct
+```
+
+> **WARNING:** ensure `/dev/mmcblk0` really is the correct device for
+> your SD card, and not used by the system!
+
+
+Booting the Board
+-----------------
+
+ 1. Connect a TTL cable to three UART pins, GND is closest to the edge
+ 2. Insert the flashed SD card
+ 3. Power-up the board using an USB-C cable (ensure good power source!)
+
+Worth noting, unlike many other boards, the Rockchip family of chipsets
+runs the UART at 1500000 bps (1.5 Mbps) 8N1.
+
+
+Secure Boot
+-----------
+
+Like other Infix builds, the R2S enjoys secure boot.  Please note,
+however that the default signing keys are the public!
+
+Also, default builds allow modifying and saving the U-Boot environment
+(see below), which you may want to disable to secure the device.  The
+device also runs in *developer mode*, allowing full U-Boot shell access,
+which you may also want to disable in a full production setting.
+
+
+Caveat
+------
+
+Most (all?) of these boards do not have any Vital Product Data (VPD)
+EEPROM mounted.  This means they do not come with unique MAC addresses
+allocated to the two Ethernet ports.
+
+The bootloader (U-Boot) default environment for the board is usually
+what provides a default, the same default MAC addresses to Linux:
+
+ - 4a:dc:d8:20:0d:84
+ - 4a:dc:d8:20:0d:85
+
+This is important in case you want to run multiple R2S devices on the
+same LAN.  Meaning you either have to change the MAC address in the
+U-Boot environment (below), or modify your `phys-address` setting in
+Infix for the interface(s).
+
+Break into U-Boot using Ctrl-C at power-on, preferably when the text
+`Press Ctrl-C NOW to enter boot menu` is displayed.  Exit the menu to
+get to the prompt:
+
+```
+(r2s) printenv
+...
+eth1addr=4a:dc:d8:20:0d:84
+ethact=ethernet@ff540000
+ethaddr=4a:dc:d8:20:0d:85
+ethprime=eth0
+...
+```
+
+Here we change both addresses, using the *Locally Administered* bit:
+
+```
+(r2s) setenv eth1addr 02:00:c0:ff:ee:01
+(r2s) setenv ethaddr 02:00:c0:ff:ee:00
+(r2s) saveenv
+```
+
+Boot the system, log into Linux, and inspect the MAC addresses:
+
+```
+admin@infix-00-00-00:~$ ip -br l
+lo      UP     00:00:00:00:00:00 <LOOPBACK,UP,LOWER_UP>
+eth0    UP     02:00:c0:ff:ee:00 <BROADCAST,MULTICAST,UP,LOWER_UP>
+eth1    UP     02:00:c0:ff:ee:01 <BROADCAST,MULTICAST,UP,LOWER_UP>
+```
+
+[1]: https://wiki.friendlyelec.com/wiki/index.php/NanoPi_R2S