docs: add a tutorial on use U-Boot and OpenSBI to boot Openwrt in qemu

docs/booting-openwrt-in-qemu-using-uboot-and-rustsbi.md

@@ -0,0 +1,165 @@
+# 使用RustSBI & U-Boot在QEMU中启动 Openwrt
+
+本教程给出了使用RustSBI和U-Boot在QEMU中启动Openwrt的基本流程。
+
+本教程使用软件版本如下：
+
+|         软件          |  版本   |
+| :-------------------: | :-----: |
+| riscv64-linux-gnu-gcc | 14.1.0  |
+|  qemu-system-riscv64  |  9.0.1  |
+|  RustSBI Prototyper   |  0.0.0  |
+|        U-Boot         | 2024.04 |
+
+## 准备RustSBI Prototyper， U-Boot ，Openwrt
+创建工作目录并进入该目录
+
+``` shell
+$ mkdir workshop && cd workshop
+```
+
+### Clone RustSBI Prototyper
+
+``` shell
+$ git clone https://github.com/rustsbi/prototyper.git && cd prototyper && git checkout main && cd ..
+```
+
+### Clone U-Boot
+
+``` shell
+$ git clone https://github.com/u-boot/u-boot.git && cd u-boot && git checkout v2024.04 && cd ..
+```
+
+### Clone & Patch Openwrt
+
+``` shell
+$ git clone https://git.openwrt.org/openwrt/openwrt.git 
+```
+
+应用以下 patch：
+```patch
+diff --git a/package/boot/uboot-sifiveu/patches/200-invalid-version.patch b/package/boot/uboot-sifiveu/patches/200-invalid-version.patch
+new file mode 100644
+index 0000000000..9bb5c814d2
+--- /dev/null
++++ b/package/boot/uboot-sifiveu/patches/200-invalid-version.patch
+@@ -0,0 +1,12 @@
++--- a/scripts/dtc/pylibfdt/Makefile
+++++ b/scripts/dtc/pylibfdt/Makefile
++@@ -17,7 +17,7 @@ quiet_cmd_pymod = PYMOD   $@
++       cmd_pymod = unset CROSS_COMPILE; unset CFLAGS; \
++               CC="$(HOSTCC)" LDSHARED="$(HOSTCC) -shared " \
++               LDFLAGS="$(HOSTLDFLAGS)" \
++-              VERSION="u-boot-$(UBOOTVERSION)" \
+++              VERSION="$(UBOOTVERSION)" \
++               CPPFLAGS="$(HOSTCFLAGS) -I$(LIBFDT_srcdir)" OBJDIR=$(obj) \
++               SOURCES="$(PYLIBFDT_srcs)" \
++               SWIG_OPTS="-I$(LIBFDT_srcdir) -I$(LIBFDT_srcdir)/.." \
++--
+diff --git a/target/linux/sifiveu/base-files/etc/inittab b/target/linux/sifiveu/base-files/etc/inittab
+index 69f97c47c8..0d8ead1d91 100644
+--- a/target/linux/sifiveu/base-files/etc/inittab
++++ b/target/linux/sifiveu/base-files/etc/inittab
+@@ -1,4 +1,5 @@
+ ::sysinit:/etc/init.d/rcS S boot
+ ::shutdown:/etc/init.d/rcS K shutdown
+ ttySIF0::askfirst:/usr/libexec/login.sh
++ttyS0::askfirst:/usr/libexec/login.sh
+ tty1::askfirst:/usr/libexec/login.sh
+```
+
+## 编译RustSBI  Prototyper
+
+进入prototyper目录
+
+``` shell
+$ cd prototyper
+```
+
+编译RustSBI  Prototyper
+
+``` shell
+$ cargo make prototyper
+```
+
+## 编译U-Boot SPL
+
+进入U-Boot目录
+
+``` shell
+$ cd u-boot
+```
+
+导出环境变量
+
+``` shell
+$ export ARCH=riscv
+$ export CROSS_COMPILE=riscv64-linux-gnu-
+$ export OPENSBI=../prototyper/target/riscv64imac-unknown-none-elf/release/rustsbi-prototyper.bin 
+```
+
+生成`.config`文件,编译U-Boot
+
+``` shell
+# To generate .config file out of board configuration file
+$ make qemu-riscv64_spl_defconfig
+$ make -j$(nproc)
+```
+
+## 编译 Openwrt
+
+首先，你应先按照 <https://openwrt.org/docs/guide-developer/toolchain/install-buildsystem> 配置自己的编译环境。
+
+（以下内容参照并修改自 <https://openwrt.org/docs/guide-developer/toolchain/use-buildsystem>）
+
+更新 Feeds：
+```shell
+cd openwrt
+# Update the feeds
+./scripts/feeds update -a
+./scripts/feeds install -a
+```
+
+修改内核配置：
+```shell
+make -j$(nproc) kernel_menuconfig
+```
+
+进入后将   
+"Device Drivers -> Serial ATA and Parallel ATA drivers (libata) -> AHCI SATA support"   
+"Device Drivers -> Network device support  -> Ethernet driver support -> Intel devices -> Intel(R) PRO/1000 Gigabit Ethernet support"  
+设为 built-in。
+
+编译镜像：
+```shell
+# Build the firmware image
+make -j$(nproc) defconfig download clean world
+```
+
+拷贝并解压镜像：
+```shell
+cd ..
+cp ./openwrt/bin/targets/sifiveu/generic/openwrt-sifiveu-generic-sifive_unleashed-ext4-sdcard.img.gz ./
+unar openwrt-sifiveu-generic-sifive_unleashed-ext4-sdcard.img.gz
+```
+
+## 使用RustSBI 原型系统和U-Boot启动 Openwrt
+
+进入`workshop`目录
+
+``` shell
+$ cd workshop
+```
+
+运行下面命令
+
+``` shell
+$ qemu-system-riscv64 \
+-machine virt -nographic -m 4096 -smp 1 \
+-bios ./u-boot/spl/u-boot-spl \
+-device virtio-net-device,netdev=eth0 -netdev user,id=eth0 \
+-device virtio-rng-pci -device ahci,id=ahci -device ide-hd,bus=ahci.0,drive=mydrive \
+-drive file=./openwrt/openwrt-sifiveu-generic-sifive_unleashed-ext4-sdcard.img,format=raw,if=none,id=mydrive \
+-device loader,file=./u-boot/u-boot.itb,addr=0x80200000 \
+-device e1000,netdev=n1 -netdev user,id=n1,hostfwd=tcp::12055-:22
+```