PYNQ-Z2启动NutShell（果壳处理器）——整理补充原官方文档

原文档链接：https://github.com/OSCPU/NutShell

这篇文章暂时先用原文档的英文版，之后会编写一个中文版文档

Compile chisel code

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• before start, git checkout release-21228

• Install mill. Refer to the Manual section in this guide.

• Run make verilog BOARD=pynq to generate verilog code. The output file is build/TopMain.v.

Run programs by simulation

You can either use our ready-to-run image for simulation or build image yourself.

To use ready-to run image (recommended) :

• Run make emu to launch simulation. Default image is linux kernel.

Run on FPGA

Sub-directories Overview

fpga
├── board              # supported FPGA boards and files to build a Vivado project
├── boot               # PS boot flow of zynq and zynqmp
├── lib                # HDL sources shared by different boards
├── Makefile
├── Makefile.check
└── NutShell.tcl       # wrapper of NutShell core in the Vivado project

Build a Vivado project

• Install Vivado 2019.1, and source the setting of Vivado and SDK
• Run the following command to build a Vivado project

cd fpga
make PRJ=myproject BOARD=pynq STANDALONE=true

Change pynq to the target board you want. Supported boards are listed under board/. The project will be created under board/pynq/build/myproject-pynq. Please note that STANDALONE mode is only used in pynq board.

• Open the project with Vivado and generate bitstream.

• To generate bitstream with vivado 2022.2, please add (* ram_style = "registers" *) before array tlbmd_0 tlbmd_2 tlbmd_3 in EmbeddedTLBMDmodule.See here for more details.

  (* ram_style = "registers" *)
    reg [120:0] tlbmd_0 [0:0];
  

prepare SD card

Stand-Alone Mode

In stand-alone mode, control is directly transferred to PL (Program Logic) through FSBL (First Stage BootLoader) after the board is powered on, so that PL has access to on-board peripherals such as SD card, Ethernet, etc., which is necessary to boot Debian and other OS.

We use PYNQ-Z2 board as example to demonstrate how to prepare SD card in stand-alone mode.

Build BOOT.BIN

BOOT.bin is the default filename of packaged hardware-related binary files. Here is a pre-built and currently-used BOOT.BIN.

You can also build it yourself. Please refer to the following process.

• create a project in Vivado and generate bitstream

  cd $(NUTSHELL_HOME)/fpga
  make PRJ=myprj BOARD=pynq STANDALONE=true vivado
  

• generate hardware description file in Vivado

  Vivado -> File -> Export -> Export Hardware
  

• do bootgen initially

  cd $(NUTSHELL_HOME)/fpga
  make bootgen PRJ=myprj BOARD=pynq STANDALONE=true
  # this will report some error messages
  

  If you want to do bootgen with Vivado 22.2 please install Vitis first.

• create project-related links

  cd $(NUTSHELL_HOME)/fpga/boot/build/zynq
  ln -sf $(NUTSHELL_HOME)/fpga/board/pynq/build/myprj-pynq/myprj-pynq.sdk/system_top_wrapper.hdf ps.hdf
  ln -sf $(NUTSHELL_HOME)/fpga/board/pynq/build/myprj-pynq/myprj-pynq.runs/impl_1/system_top_wrapper.bit fpga.bit
  # modify FSBL_LOC in $(NUTSHELL_HOME)/fpga/resource/fsbl-loader/Makefile like this:
  # FSBL_LOC = ../../boot/build/myprj-pynq/fsbl
  

• generate BOOT.BIN

  cd $(NUTSHELL_HOME)/fpga
  make bootgen PRJ=myprj BOARD=pynq STANDALONE=true
  

Build RV_BOOT.bin

RV_BOOT.bin is the default filename of linux-kernel image. Here is a pre-built and currently-used image. You can also build it yourself by riscv-pk and riscv-linux (currently not avaliable to the public).

Build rootfs in SD card

Save the contents before the SD card in case of loss

mount -t vfat /dev/mmcblk0p1 /mnt
mkdir sd_card_save
cp /mnt/* sd_card_save
umount /mnt

1. Prepare

//umount the SD card
umount /dev/sdb*

1. Partition

# creat two partitions in SD card
sudo fdisk /dev/sdb

• Delete the partition before execute the steps

• New partitions

• Or use sudo cfdisk /dev/sdb to create partition

1. Format

mkfs.vfat /dev/sdb1
mkfs -t ext4 /dev/sdb2

if you see the following error report after executing mkfs -t ext4 /dev/sdb2 , you can change partition type by using sudo cfdisk /dev/sdb , see here for more details.

mkfs.ext4: inode_size (128) * inodes_count (0) too big for a
        filesystem with 0 blocks, specify higher inode_ratio (-i)
        or lower inode count (-N).

1. mount

mount -t ext4 /dev/sdb2 /mnt
mkdir /mnt/boot
mount -t vfat /dev/sdb1 /mnt/boot

1. copy

copy the files which has been generated before into /dev/sdb1

• BOOT.BIN
• RV_BOOT.BIN

1. download the debian base system to sdb2 with qemu-debootstrap , and enter the command below.

sudo su
qemu-debootstrap --arch riscv64 unstable /mnt http://deb.debian.org/debian-ports
chroot /mnt /bin/bash
passwd
apt-get update
apt-get install net-tools openssh-server vim build-essential minicom tmux libreadline-dev
exit

1. Add a line of ttyPS0 in /mnt/etc/securetty to allow login debian via ttyPS0. See here for more details.

2. Add a line of PermitRootLogin yes in /mnt/etc/ssh/sshd_config to enable root login via ssh. See here for more details.

3. Add the following lines to /mnt/etc/fstab

# <file system> <mount point> <type>  <options> <dump>  <pass>
proc /proc proc defaults 0 0
/dev/mmcblk0p1 /boot vfat defaults 0 2
/dev/mmcblk0p2 / ext4 errors=remount-ro 0 1