Z-turn-Board-V2-Diary

🌷 Creating (and compiling) a project 🌌

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Outline:

• Create a project
• Do minor assisting configurations
  • (x3).
• Build project
• Retrieve(package) boot files

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🏛️(Create a new project):

We will not be using pre-configured settings. (This would be possible by using a bsp file).
(Thus, we will rely on templates).

• Create a new project, [specific to our logic design]:
  $ petalinux-create --type project --template zynq --name my_project
$ cd my_project
• Configure according to the logic design:
  $ petalinux-config --get-hw-description path/to/exported/design_1_wrapper.xsa --silentconfig
  ^ This should be run only once, because it initializes. Any subsequent configurations, should be through $ petalinux-config (w/o params).

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🏛️(menuconfig: Cache)

To save download time, we can download various caches. There are two of them, the “download” and the “sstate” one. Namely, under the PetaLinux Tools sstate-cache Artifacts, the following can be downloaded:

• “arm sstate-cache”, and
• “Downloads”

Extract both of them and note the destination paths like so:

• downloads_path: file:///path/to/downloads/inner/downloads/folder
• sstate_path: /path/to/sstate/top/arm/folder
  ^ (Absolute paths may be needed)! (Instead of relative ones).

To set them:

• Open menuconfig: $ petalinux-config
• copy downloads_path to Yocto-settings ⟶ Add pre-mirror URL, and
• sstate_path to Yocto Settings ⟶ Local sstate feeds settings:

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🏛️(menuconfig: New partition)

(Instead of loading Linux onto [board’s] RAM (default/image.ub)),
We will install, Linux, directly onto the SD(ext4) card.

• Open menuconfig: $ petalinux-config
• Image Packaging Configuration ⟶ Root filesystem type ⟶ EXT4
  ^ (This will automatically affect other [configuration] areas).

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🏛️(menuconfig: Extra(threads))

• Yocto Settings ⟶ Parallel thread execution

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🏛️(menuconfig: Extra(auto-login))

(As per reference), Open the rootfs configuration:
$ petalinux-config -c rootfs

• Image Features ⟶ serial-autologin-root

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🏛️(SD read-write):

In order to not boot read-only, we’ll need a device tree specification.
Taken from the original source code, we’ll adapt the device tree specifications (files system-user.dtsi and zturn-pl-hdmi.dtsi (the .dtsi stands for Device Tree Source Include)), too isolate the SD part: (and adapt the system-user.dtsi file):

my_project/project-spec/meta-user/recipes-bsp/device-tree/files/system-user.dtsi:

/include/ "system-conf.dtsi"
/ {
    aliases {
		mmc0 = &sdhci0;
	};
};

&sdhci0 {
	status = "okay";
	disable-wp;
	// wp-inverted;
};

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🏛️(Build the project):

• $ petalinux-build
  ^ (Note: You may wanna save the build/downloads folder to reduce download times).

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🏛️(Package the boot images):

FIXME: Why?

• Prepare the boot images, including the bitstream, using:
  $ petalinux-package --boot --u-boot --fpga project-spec/hw-description/design_1_wrapper.bit
  ^ The important part is (--fpga path/bit) to include the bitstream.
  _ Amongst the errors, are inability to find the interrupt controller (boot hang).
  Note:
  • project-spec/hw-description/design_1_wrapper.bit is updated after $ petalinux-config, whereas
  • images/linux/system.bit may not be updated
• This will create the:
  • BOOT.BIN, boot.scr, image.ub files which contain the bootloader (?), the (?) [reference] and the kernel, along with:
  • rootfs.tar.gz, which will be extracted onto the SD.

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Note(corrections)

As per the tutorial:

• boot.scr is the script that U-Boot reads during boot time to load the kernel and rootfs
• image.ub contains kernel image, device tree and rootfs

Thus, up to the previous chapter, the ext4 (where the rootfs.tar.gz was extracted) was not being used 🙊!

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Boot:

As per reference:

• Copy the BOOT.bin, boot.scr and image.ub files into a FAT32 partition of the SD card
  (Preferably, the FAT32 is (at least (?)) 4MiB after the start).
• Extract rootfs.tar.gz into an ext4 partition

(You can monitor the boot process with picocom or CuteCom).

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Various troubleshooting from the internet:

• Some fixed by reinstalling petalinux
• Petalinux 2023.2 known issues (site)

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Referencies

• UG1144: PetaLinux Tools Documentation: Reference Guide (site)
• [The original] Source code (chinese site)
• Add EXT4 rootfs support (tutorial)

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