08-19-2017, 02:53 PM
You can install any linux configuration you want on the Pinebook.
First bit of information you will find valuable, is that from a software perspective, eMMC is just an SD card. So effectively, the Pinebook has 2 SD cards, in in eMMC form, and one external.
Next up is how the pinebook starts up. It can startup from the external SD card or the eMMC. This always happens, is not configurable or software changeable. (extreme tech details: http://linux-sunxi.org/BROM )
From the SD card/eMMC u-boot is loaded, this is the first piece of software that is configurable. u-boot configures the system memory and loads the linux kernel. It's pretty much the BIOS+GRUB from what you know.
The linux kernel, I assume you are a bit familiar with this. However, on a normal desktop system, you can have a generic kernel that auto-detects all your hardware. On ARM, things are a bit less simple. The kernel doesn't have to be hardware specific, but hardware auto-detection isn't as well defined as on the desktop. Which is why you need something called the "device tree", which describes the hardware configuration.
In case of the pinebook, both u-boot, the kernel and the device tree are very device specific. You can build your own from source. But I would recommend using the ones from: https://github.com/ayufan-pine64/linux-build/releases/ (0.6.2 is currently considered stable)
The kernel and device tree are "easy" to install, the parts are generally located in /boot/ for the kernel and device tree. The device tree is named ".dtb", kernel usually "uImage-something".
u-boot however, is installed "raw" on the SD card/eMMC. Check /usr/local/sbin/pine64_update_uboot.sh to see how it is installed.
Now, if you are still following. If you want to go and build your system up from scratch, you'll see that it's important to see the information on what is happening during these first parts. Note that this doesn't differ much from and ARM Linux SBC. For this, you will need a serial port or UART as it called officially. The UART of the Pinebook is accessible trough the headphone port, but for that you need to flip a physical switch inside the pinebook. And you will need to make a custom cable to hook up the phone hack to another computer.
For this, you will most likely want an USB-Serial converter. You can buy these online for less then $10, get one for 3.3v, not 5v. The pinebook resources page contains info on how to connect it (sort of). With this cable you can access the u-boot console, and the linux kernel output you would normally see on a normal computer screen unless some boot splash overrules it.
You most likely have information overload already now :-) So just ping back if this is still interesting for you.
(At my day job we have our own setup on a SBC, which is part of my responsibility. So I know how to set this up quite well and how to do it from scratch)
First bit of information you will find valuable, is that from a software perspective, eMMC is just an SD card. So effectively, the Pinebook has 2 SD cards, in in eMMC form, and one external.
Next up is how the pinebook starts up. It can startup from the external SD card or the eMMC. This always happens, is not configurable or software changeable. (extreme tech details: http://linux-sunxi.org/BROM )
From the SD card/eMMC u-boot is loaded, this is the first piece of software that is configurable. u-boot configures the system memory and loads the linux kernel. It's pretty much the BIOS+GRUB from what you know.
The linux kernel, I assume you are a bit familiar with this. However, on a normal desktop system, you can have a generic kernel that auto-detects all your hardware. On ARM, things are a bit less simple. The kernel doesn't have to be hardware specific, but hardware auto-detection isn't as well defined as on the desktop. Which is why you need something called the "device tree", which describes the hardware configuration.
In case of the pinebook, both u-boot, the kernel and the device tree are very device specific. You can build your own from source. But I would recommend using the ones from: https://github.com/ayufan-pine64/linux-build/releases/ (0.6.2 is currently considered stable)
The kernel and device tree are "easy" to install, the parts are generally located in /boot/ for the kernel and device tree. The device tree is named ".dtb", kernel usually "uImage-something".
u-boot however, is installed "raw" on the SD card/eMMC. Check /usr/local/sbin/pine64_update_uboot.sh to see how it is installed.
Now, if you are still following. If you want to go and build your system up from scratch, you'll see that it's important to see the information on what is happening during these first parts. Note that this doesn't differ much from and ARM Linux SBC. For this, you will need a serial port or UART as it called officially. The UART of the Pinebook is accessible trough the headphone port, but for that you need to flip a physical switch inside the pinebook. And you will need to make a custom cable to hook up the phone hack to another computer.
For this, you will most likely want an USB-Serial converter. You can buy these online for less then $10, get one for 3.3v, not 5v. The pinebook resources page contains info on how to connect it (sort of). With this cable you can access the u-boot console, and the linux kernel output you would normally see on a normal computer screen unless some boot splash overrules it.
You most likely have information overload already now :-) So just ping back if this is still interesting for you.
(At my day job we have our own setup on a SBC, which is part of my responsibility. So I know how to set this up quite well and how to do it from scratch)
