bootloader for quartz64-a

jyoung · Guru Joined: 20 Mar 2007 Posts: 445

Hi,

I'm setting up gentoo on a quartz64 model-a (64-bit arm SBC), and I'm stumped on the bootloader. From what I've read, the only option is the u-boot bootloader. However, building u-boot for this processor (rk3566) requires a TPL binary. Here's what I've done:

First, some info on the board

www.pine64.org/quartz64a/

The pine64 folks do provide a small amount of information about setting up a bootloader
https://wiki.pine64.org/wiki/Quartz64_UEFI_with_U-Boot

Crucially, this does eventually lead to a github page for a u-boot build appropriate for this processor
https://github.com/Kwiboo/u-boot-rockchip.git

Okay, when I clone this page, setup the config for this processor, and then make

pingtoo · Posted: Sat Aug 05, 2023 4:56 pm Post subject:

Are you intent to replace the u-boot with your own? Setup Gentoo does not require a new u-boot.

Setup Gentoo primary is create a rootfs with Gentoo content. Optionally replace kernel with you own compilation.

So I suggest you use existing bootstrap process get a working rootfs with Gentoo content before trying to get u-boot work.

If you really want to replace u-boot, we can try try to review the process in more detail to understand what procedure will lead to success.

jyoung · Guru Joined: 20 Mar 2007 Posts: 445

Okay, some progress: NeddySeagoon pointed me toward this tutorial

https://gitlab.collabora.com/hardware-enablement/rockchip-3588/notes-for-rockchip-3588/-/blob/main/upstream_uboot.md

Technically, this is for the rk3588, but it does explain how to pass the TPL binary path to make

jyoung · Guru Joined: 20 Mar 2007 Posts: 445

pingtoo, that sounds like a good idea. Can you post a link to that material?

pingtoo · Posted: Sat Aug 05, 2023 5:33 pm Post subject:

jyoung · Guru Joined: 20 Mar 2007 Posts: 445

Interesting, this aligns fairly well with one of my first attempts. I tried to boot off armbian and install gentoo on a second disk using the normal install procedures. But, I'd still need to setup a bootloader. I first tried grub, but I don't think that grub is supports this type of board (correct me if I'm wrong here, using grub would be much easier). After that, I began experimenting with u-boot.

Another idea I tried was to write the armbian disk to an image, but overwrite the linux partition with gentoo, carefully preserving the /boot path structure so that the bootloader on the armbian image would lock onto the gentoo kernel image. That didn't work either, although I might try that again.

Or, are you thinking of something different pingtoo? One of the items in the tutorial you linked suggested installing gentoo side by side on the same disk as an existing install. That's an interesting idea, although we'd need to get the bootloader to detect gentoo as an option.

NeddySeagoon · Posted: Sat Aug 05, 2023 6:57 pm Post subject:

jyoung,

You also need /lib/modules from the donor OS, as they will match to donor kernel.
You may need /lib/firmware too, in case there are any special firmware files that Gentoo will not provide.

In general, if you get all the bits in / that the donor needs, it should get you started.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

pingtoo · Posted: Sat Aug 05, 2023 7:14 pm Post subject:

I don't have rk3588 board on hand, so I cannot give you specific instruction.

Usually u-boot have autoboot feature turn on but the setting will give you a few seconds before device probing. so you can press any key to interrupt boot sequence. this will drop you at u-boot prompt.

u-boot is equivalent to grub in PC world. with some effort it is possible to program u-boot to give a menu to allow you select boot media and/or program to run (kernel is just a elf program)

I will use my rk3399 board (nanopi r4s) as example. my board boot off from a microSD card, so it is show as MMC in Linux kernel.

jyoung · Guru Joined: 20 Mar 2007 Posts: 445

NeddySeagoon, if I got that route, would I then be able to install a gentoo kernel?

pingtoo, the u-boot that comes with armbian isn't able to display, at least not on the hdmi monitor that I have. I've been trying to get a display through the serial pins through a usb adapter using minicom, but without much luck. This wiki gives the pin connections in the "Connect Debug UART" section

https://wiki.pine64.org/wiki/Quartz64

And this is the device that I've been using

http://www.adafruit.com/product/954

NeddySeagoon · Posted: Mon Aug 07, 2023 11:49 am Post subject:

jyoung,

If the gentoo kernel supports your hardware, yes.

The userland is the easy bit. The kernel can be difficult if you need to track down the device tree sources and vendor specific patches, or close to impossible if you really need evil binary only kernel modules. They will be tied to specific kernel and gcc versions.

e.g. My old arm64 chromebook needs the 3.14 kernel to have any video acceleration at all as the video driver is an evil binary only kernel module.
That won't run properly under a modern gentoo install as the userland makes system calls the kernel doesn't have.

I can use fbdev but then the GPU is just a chunk of RAM. The CPU plots every pixel.

More difficult than the kernel is the boot loader. If it works, just use it. It can be made to boot whatever you tell it.
Flashing the boot loader can be scary. You may need JTAG to recover.

If you don't know what JTAG is, don't risk it, unless its all on removable media that can be reprogrammed elsewhere.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

pingtoo · Posted: Mon Aug 07, 2023 2:05 pm Post subject:

jyoung,

Similar to Neddy suggestion, I would separate this objective in to smaller portion and tackle it one by one.

3 portions as in

rootfs (gentoo based)
bootloader(u-boot or what not)
kernel

I will not go much of the rootfs since it is already discussed in previous posts.

for the bootloader portion, you will need to access to console in order to make adjustment. so question, How do you access armbian? over ssh? can you check the kernel command line to see if kernel was programmed to output to serial console? finial I saw the wiki page you point to about using UART, it stated that possible incorrect label about pins, so have you try to change pins to see if that is case?

Only having above than tackle kernel will make things a lot easier.

NeddySeagoon · Posted: Mon Aug 07, 2023 7:00 pm Post subject:

jyoung,

Like pingtoo says, if you are going to eat a whole elephant, do it one plateful at a time. :)
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

jyoung · Guru Joined: 20 Mar 2007 Posts: 445

So far I've been accessing armbian over ssh, although it does output to hdmi also.

I think I found the issue with the uart: serial/usb conversion wasn't enabled in the kernel on my desktop. Let me update that, and get back to you folks.

jyoung · Guru Joined: 20 Mar 2007 Posts: 445

Okay, I have the usb/serial driver installed, and I'm booting up the board with the armbian image. The wiki recommends to invoke picocom as so

NeddySeagoon · Posted: Tue Aug 08, 2023 8:18 pm Post subject:

jyoung,

The baud rate, the 1500000 bit, needs to be the same both ends or you will get nothing or jibbereish, depending on you luck.
The parity and number oy stop bits needs to match too.

No parity and one stop bit is common.

Baby steps.

Connect your usb/serial doda to your PC but not to anything else. Keep at the wires separate.
Set up minicom for 1500000n1 and no handshake.
Turn off local echo, or you will be confused when thus works.

Type into minicom. you should see nothing.

Connect the Tx and Rx wires together. This is called a loopback test.

Type into minicom again.
This time you should see what you type echoed back to you. Your typing is going out of the Tx pin and back into the Rx pin, so you see it in minicom.

Until this works, there is no point in trying to see the serial console on your target board.

Next steps, the kernel serial part settings will be on the kernel command line on the target.
Have a look in dmesg.

jyoung · Guru Joined: 20 Mar 2007 Posts: 445

NeddySeagoon, from what I'm seeing I can turn off local echo within minicom with ctrl A+E. How do I set it up without a handshake?

jyoung · Guru Joined: 20 Mar 2007 Posts: 445

Okay, I tried these two tests, running minicom without and then with the RX and TX pins connected. As suggested, I invoked it with

NeddySeagoon · Posted: Thu Aug 10, 2023 3:54 pm Post subject:

jyoung,

jyoung · Guru Joined: 20 Mar 2007 Posts: 445

Okay, when I open up the setup menu on minicom, I see this:

jyoung · Guru Joined: 20 Mar 2007 Posts: 445

The loopback test isn't working, but optimistically I just tried to connect to the quartz64 with

NeddySeagoon · Posted: Sat Aug 12, 2023 7:08 pm Post subject:

jyoung,

Reading the UART section of that link,

jyoung · Guru Joined: 20 Mar 2007 Posts: 445

Sorry, that was the wrong link. That is for the quartzpro64 board, which is slightly different. Here is the correct link

https://wiki.pine64.org/wiki/Quartz64

On the board, /proc/cmdline has

NeddySeagoon · Posted: Sat Aug 12, 2023 9:37 pm Post subject:

jyoung,

pingtoo · Posted: Sun Aug 13, 2023 3:23 pm Post subject:

NeddySeagoon · Posted: Sun Aug 13, 2023 4:51 pm Post subject:

jyoung,

We need to see lsusb showing the USB/Serial converter.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.