UART no longer works after update

#1

Hello,
On some tests I updated to latest radxa ubuntu and kernel, probably it updated something more than just sd card (maybe spi?). Soon after that I reboot board and it did not start again (no blue led). I flashed image to eMMC and system booted again with eMMC only.
Later I tried few other things and found out that it won’t boot anymore with uart console attached. Same that worked perfectly some time ago. I checked another uart console with same effect. Then I get second rock3a board and that one works with both uarts. Same setup - card, charger, cooling, the only difference is v1.2 vs v.1.3 board revision but according to @jack this should not be big difference.

Then I tried RKTools instructions found on wiki, trying to burn spi with latest u-boot and loader. No luck :frowning:
Then with cleared SPI - still nothing.

Any ideas how to make UART to work again? For now no matter what Im trying it won’t boot with uart cable conected. Nothing on com port and won’t boot into the system. It’s even worse than when I connected not supported UART cable which caused to stop at u-boot.

On RKTools there is tab about firmware - what firmware is that? and how to updated this one?
Of course I still can boot into system and try to update or read anything just from there. Also I still have another board with working UART to compare (or update ;))

any ideas? @jack @Stephen ?

this may be the same issue as @james.kraber - I expected that with right UART console board should write some information on boot, right now mine is not booting with console.

Rock3a update firmware from board
#2

any ideas?
Is there any way to revert bootloader to older version?

Rock 3A no power after SSD boot attempt
#3

Hi,
Faced somewhat similar situation with UART. At some point after countless number of flashes and reboots (messing with building Android, used serial console for debug purposes) it just got stuck with nothing being printed on debug console. Re-flashing the whole image (i’m using sdcard, not emmc) seems made things better - was able to boot but still nothing on the UART. So I thought smth is wrong with my image and tried with stock Debian - still nothing…
Finally I found that UART TX pin does not work anymore while RX still works.
No idea what and where it went wrong but ended up with patching U-BOOT and Kernel to use UART8

#4

Have You tried to boot from nvme instructions? All my troubles started right after those. That’s why I’m looking for list of firmwares that were updated.

Where first stage bootloader is located?

#5

No, mine SPI flash stays untouched (blank I assume)
First stage is on the chip itself I guess, then SPL/TPL from the storage device.

ps: so i’m afraid it could be a hardware malfunction… at least in my case… :-[

#6

On RKDevTools one tab is for firmware, what is that? Is that firmware for SoC? I could not find option to read version or image, it forces me to select something (probably to upgrade). Is that SoC firmware?

I made few other tests now, first connected to windows on RKDevTools, it finds maskroom device but I can’t do anything, even simple operation like ReadFlashId:

rock3a-fail

On second rock3A everything is OK.

Also I confirmed that board starts without one uart line, second throws some mess on console, maybe baudrate is different? This seems to be same problem as Yours.

#7

I found one more interesting thing. When I select boot image and “download” rkdevTools functions are working again:

image
image.png739×417 9.71 KB

Those are tests from board with UART problems. I assume that upgraded image is faulty but I can boot good one. Now I need to burn that into SOC, but this don’t work on both boards, maybe something wrong about cable (Prepare IDB Fail).

#8

Regarding boot sequence, see https://dl.radxa.com/rock3/docs/hw/datasheet/Rockchip%20RK3568%20TRM%20Part1%20V1.1-20210301.pdf
Section “1.2 System Boot”, so there’s some “romcode” at 0xFFFF0000 which executes SPL.
There are not much details about this “romcode” but I assume all the hw initialization is done by SPL actually. Also I’m in doubt we could manage to overwrite “romcode” somehow by accident. Well, at least I did not do anything special on this regard… :wink:

#9

Right before there was a problem I tried to move system to nvme and boot from that one (only that one). For this I needed rock3-latest packages by @Stephen and one of them have been updating something, right after that it did not boot again (uart console was connected).
I was sure that it updates SPI with u-boot, but this should not affect UART and first phase of boot.