QEMU 启动方式分析 (1):QEMU 及 RISC-V 启动流程简介
作者:互联网
Author: YJMSTR jay1273062855@outlook.com
Date: 2022/08/16
Revisor: Bin Meng, Falcon
Project: RISC-V Linux 内核剖析
Sponsor: PLCT Lab, ISCAS
QEMU 启动方式分析 (1):QEMU 及 RISC-V 启动流程简介
使用软件版本如下:
QEMU: v7.0.0
OpenSBI: v1.1
U-Boot: v2022.04
Linux Kernel: v5.18
QEMU 简介
什么是 QEMU
QEMU (Quick Emulator) 是一个开源的通用机器仿真器与虚拟化工具,主要支持以下使用方式:
- 用户模式仿真 (User Mode Emulation) :在该仿真方式下,QEMU 可以在一种架构的 CPU 上运行为另一种架构的 CPU 编译的程序。
- 系统仿真 (System Emulation) :在该仿真方式下,QEMU 提供运行客户机所需的完整环境,包括 CPU,内存和外围设备。
当使用 QEMU 模拟 RISC-V 架构时,QEMU 能够提供 virt
虚拟开发板,它不对应现实中的任何硬件,但它支持模拟多种硬件设备。在接下来分析 QEMU 的启动方式时,本系列文章均以 QEMU 'virt' 机器作为实验平台。Linux Lab 中也提供了 riscv32/virt
与 riscv64/virt
这两个虚拟开发板,可以用于 RISC-V 的学习。
QEMU RISC-V 环境构建
Linux Lab 中集成了 QEMU,支持一键自动编译等功能,具体可以参考 Linux Lab 官方手册,当前的 Linux Lab 版本是 v1.0。
下载并构建支持 RISC-V 的 QEMU 的流程如下:
$ wget https://download.qemu.org/qemu-7.0.0.tar.xz
$ tar xvJf qemu-7.0.0.tar.xz
$ cd qemu-7.0.0
$ ./configure --target-list="riscv32-softmmu riscv64-softmmu"
$ make -j $(nproc)
$ make install
安装完成后在终端中输入 qemu-system-riscv64 --version
,如果显示以下文字,则说明安装成功:
QEMU emulator version 7.0.0
Copyright (c) 2003-2022 Fabrice Bellard and the QEMU Project developers
RISC-V 启动流程简介
如下图所示,RISC-V 引导流程分为多个阶段,我们重点关注 OpenSBI 与 U-Boot。
)
ZSBL
ZSBL (Zero Stage Boot Loader) 从 ROM 中获取核心代码。
FSBL:U-Boot SPL
FSBL (First Stage Boot Loader) 由 Soc 指定,可能是 CoreBoot 或 U-Boot SPL。这一阶段将会完成 DDR 的初始化,并载入运行时环境 (runtime) 与引导加载器 (bootloader)。
其中,U-Boot SPL 是一个非常小的 loader 程序,其主要功能是加载真正的 U-Boot 并运行。具体的加载过程可以参考 RISC-V UEFI 架构支持详解,第 1 部分 - OpenSBI/U-Boot/UEFI 简介 - 泰晓科技 (tinylab.org) 中 U-Boot 相关部分。在编译 U-Boot 之前需要先编译 OpenSBI。
Runtime:OpenSBI
RISC-V 的 Runtime 通常是 OpenSBI,它是运行在 M 模式下的程序,但能够为 S 模式提供一些特定的服务,这些服务由 SBI (Supervisor Binary Interface) 规范定义。
SBI 是指 Supervisor Binary Interface,它是运行在 M 模式下的程序,操作系统通过 SBI 来调用 M 模式的硬件资源。而 OpenSBI 是指西数开发的一种开源 SBI 实现。RISC-V OpenSBI 快速上手 - 泰晓科技 (tinylab.org) 这篇文章给出了在 Linux Lab 中编译运行 OpenSBI 的教程。
OpenSBI 有三种 Firmware:
- FW_PAYLOAD :下一引导阶段被作为 payload 打包进来,通常是 U-Boot 或 Linux。这是兼容 Linux 的 RISC-V 硬件所使用的默认 firmware 。
- FW_JUMP :跳转到一个固定地址,该地址上需存有下一个加载器。QEMU 的早期版本曾经使用过它。
- FW_DYNAMIC :根据前一个阶段传入的信息加载下一个阶段。通常是 U-Boot SPL 使用它。现在 QEMU 默认使用 FW_DYNAMIC。
下载并编译 OpenSBI 的流程如下:
$ git clone https://gitee.com/tinylab/qemu-opensbi.git
$ cd qemu-opensbi/
$ export CROSS_COMPILE=riscv64-linux-gnu-
$ make all PLATFORM=generic PLATFORM_RISCV_XLEN=64
其中 PLATFORM 选择 qemu_virt 所需的 generic 平台。
Bootloader:U-Boot
Bootloader 是嵌入式系统在加电后执行的较为早期的代码,这段程序将会完成硬件的初始化与环境设置等操作,再将操作系统映像或嵌入式应用程序载入内存,然后跳转到操作系统所在空间,启动操作系统。
U-Boot 指 Universal Boot Loader,是一种流行的嵌入式 Linux 系统引导加载程序。它分为 U-Boot SPL 与 U-Boot 两部分,其中 SPL 指第二阶段程序加载器(Secondary Program Loader)。
U-Boot SPL 在之前的 "FSBL/U-Boot SPL" 小节已经介绍过,这里主要谈谈 U-Boot 本身。它被 U-Boot SPL 加载进内存后,将会发挥 Bootloader 的作用。在 这篇文章 中有对 U-Boot 加载过程以及代码的分析。
下载 U-Boot:
$ git clone https://gitee.com/mirrors/u-boot.git
$ cd u-boot
$ git checkout v2022.04
为了通过 U-Boot 启动 RISC-V 64 架构的 Linux,我们需要在编译时选择交叉编译工具链 riscv64-linux-gnu-gcc。在 u-boot 目录下执行以下命令:
$ export CROSS_COMPILE=riscv64-linux-gnu-
$ make qemu-riscv64_smode_defconfig
$ make -j $(nproc)
如果想直接引导 S 模式下的 U-Boot 镜像,使用以下命令:
$ qemu-system-riscv64 -M virt -smp 4 -m 2G \
-display none -serial stdio \
-kernel /path/to/u-boot.bin
其中 /path/to/u-boot.bin
指之前编译出的 u-boot.bin
所在路径。
如需启动 U-Boot 或 Linux,需要在 OpenSBI 编译时指定 U-Boot 或 Linux 的 payload 路径。以 U-Boot 为例,切换到 OpenSBI 目录下,编译命令如下:
$ export CROSS_COMPILE=riscv64-linux-gnu-
$ make PLATFORM=generic FW_PAYLOAD_PATH=<uboot_build_directory>/u-boot.bin
运行:
$ qemu-system-riscv64 -M virt -m 256M -nographic \
-bios build/platform/generic/firmware/fw_payload.elf
或是使用以下命令运行:
$ qemu-system-riscv64 -M virt -m 256M -nographic \
-bios build/platform/generic/firmware/fw_jump.bin \
-kernel <uboot_build_directory>/u-boot.bin
如果要使用 U-Boot SPL,使用如下命令:
$ export CROSS_COMPILE=riscv64-linux-gnu-
$ cd /path/to/u-boot
$ export OPENSBI=/path/to/opensbi/build/platform/generic/firmware/fw_dynamic.bin
$ make qemu-riscv64_spl_defconfig
$ make -j $(nproc)
$ qemu-system-riscv64 -M virt -smp 4 -m 2G \
-display none -serial stdio \
-bios /path/to/u-boot-spl \
-device loader,file=/path/to/u-boot.itb,addr=0x80200000
OS:Linux
编译内核需要使用交叉编译工具链。
在终端中执行以下命令:
$ mkdir linux-kernel
$ cd linux-kernel
$ git init
$ git fetch git@gitee.com:mirrors/linux_old1.git
// 如果断了,可以多次执行 git fetch,以便实现续传
$ git checkout v5.18
随后进行内核的配置与编译:
$ make ARCH=riscv CROSS_COMPILE=riscv64-linux-gnu- defconfig
$ make ARCH=riscv CROSS_COMPILE=riscv64-linux-gnu- -j $(nproc)
编译出的 kernel image 位于 arch/riscv/boot/Image
.
随后我们用 busybox 构建根文件系统 rootfs,首先下载编译 busybox:
$ git clone https://gitee.com/mirrors/busyboxsource
$ cd busyboxsource
$ export CROSS_COMPILE=riscv64-linux-gnu-
$ make defconfig
$ make menuconfig
# 这里启用了 Settings-->Build Options 里的 Build static binary (no shared libs) 选项
$ make -j $(nproc)
$ make install
制作文件系统并新建一个启动脚本:
$ cd ~
$ qemu-img create rootfs.img 1g
$ mkfs.ext4 rootfs.img
$ mkdir rootfs
$ sudo mount -o loop rootfs.img rootfs
$ cd rootfs
$ sudo cp -r ../busyboxsource/_install/* .
$ sudo mkdir proc sys dev etc etc/init.d
$ cd etc/init.d/
$ sudo touch rcS
$ sudo vi rcS
编辑启动脚本 rcS 中的内容如下:
#!/bin/sh
mount -t proc none /proc
mount -t sysfs none /sys
/sbin/mdev -s
并修改文件权限:
$ sudo chmod +x rcS
$ cd ~
$ sudo umount rootfs
随后尝试直接引导内核:
$ qemu-system-riscv64 -M virt -m 256M -nographic \
-kernel linux-kernel/arch/riscv/boot/Image \
-drive file=rootfs.img,format=raw,id=hd0 \
-device virtio-blk-device,drive=hd0 \
-append "root=/dev/vda rw console=ttyS0"
启动日志如下:
OpenSBI v1.0
____ _____ ____ _____
/ __ \ / ____| _ \_ _|
| | | |_ __ ___ _ __ | (___ | |_) || |
| | | | '_ \ / _ \ '_ \ \___ \| _ < | |
| |__| | |_) | __/ | | |____) | |_) || |_
\____/| .__/ \___|_| |_|_____/|____/_____|
| |
|_|
Platform Name : riscv-virtio,qemu
Platform Features : medeleg
Platform HART Count : 1
Platform IPI Device : aclint-mswi
Platform Timer Device : aclint-mtimer @ 10000000Hz
Platform Console Device : uart8250
Platform HSM Device : ---
Platform Reboot Device : sifive_test
Platform Shutdown Device : sifive_test
Firmware Base : 0x80000000
Firmware Size : 252 KB
Runtime SBI Version : 0.3
Domain0 Name : root
Domain0 Boot HART : 0
Domain0 HARTs : 0*
Domain0 Region00 : 0x0000000002000000-0x000000000200ffff (I)
Domain0 Region01 : 0x0000000080000000-0x000000008003ffff ()
Domain0 Region02 : 0x0000000000000000-0xffffffffffffffff (R,W,X)
Domain0 Next Address : 0x0000000080200000
Domain0 Next Arg1 : 0x000000008f000000
Domain0 Next Mode : S-mode
Domain0 SysReset : yes
Boot HART ID : 0
Boot HART Domain : root
Boot HART ISA : rv64imafdcsuh
Boot HART Features : scounteren,mcounteren,time
Boot HART PMP Count : 16
Boot HART PMP Granularity : 4
Boot HART PMP Address Bits: 54
Boot HART MHPM Count : 0
Boot HART MIDELEG : 0x0000000000001666
Boot HART MEDELEG : 0x0000000000f0b509
[ 0.000000] Linux version 5.18.0 (yjmstr@yjmstr) (riscv64-linux-gnu-gcc (Ubuntu 11.2.0-16ubuntu1) 11.2.0, GNU ld (GNU Binutils for Ubuntu) 2.38) #2 SMP Sun Aug 14 13:14:26 CST 2022
[ 0.000000] OF: fdt: Ignoring memory range 0x80000000 - 0x80200000
[ 0.000000] Machine model: riscv-virtio,qemu
[ 0.000000] efi: UEFI not found.
[ 0.000000] Zone ranges:
[ 0.000000] DMA32 [mem 0x0000000080200000-0x000000008fffffff]
[ 0.000000] Normal empty
[ 0.000000] Movable zone start for each node
[ 0.000000] Early memory node ranges
[ 0.000000] node 0: [mem 0x0000000080200000-0x000000008fffffff]
[ 0.000000] Initmem setup node 0 [mem 0x0000000080200000-0x000000008fffffff]
[ 0.000000] SBI specification v0.3 detected
[ 0.000000] SBI implementation ID=0x1 Version=0x10000
[ 0.000000] SBI TIME extension detected
[ 0.000000] SBI IPI extension detected
[ 0.000000] SBI RFENCE extension detected
[ 0.000000] SBI SRST extension detected
[ 0.000000] SBI HSM extension detected
[ 0.000000] riscv: base ISA extensions acdfhim
[ 0.000000] riscv: ELF capabilities acdfim
[ 0.000000] percpu: Embedded 18 pages/cpu s34040 r8192 d31496 u73728
[ 0.000000] Built 1 zonelists, mobility grouping on. Total pages: 64135
[ 0.000000] Kernel command line: root=/dev/vda rw console=ttyS0
[ 0.000000] Dentry cache hash table entries: 32768 (order: 6, 262144 bytes, linear)
[ 0.000000] Inode-cache hash table entries: 16384 (order: 5, 131072 bytes, linear)
[ 0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
[ 0.000000] Virtual kernel memory layout:
[ 0.000000] fixmap : 0xff1bfffffee00000 - 0xff1bffffff000000 (2048 kB)
[ 0.000000] pci io : 0xff1bffffff000000 - 0xff1c000000000000 ( 16 MB)
[ 0.000000] vmemmap : 0xff1c000000000000 - 0xff20000000000000 (1073741824 MB)
[ 0.000000] vmalloc : 0xff20000000000000 - 0xff60000000000000 (17179869184 MB)
[ 0.000000] lowmem : 0xff60000000000000 - 0xff6000000fe00000 ( 254 MB)
[ 0.000000] kernel : 0xffffffff80000000 - 0xffffffffffffffff (2047 MB)
[ 0.000000] Memory: 237564K/260096K available (6460K kernel code, 4865K rwdata, 2048K rodata, 2165K init, 334K bss, 22532K reserved, 0K cma-reserved)
[ 0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
[ 0.000000] rcu: Hierarchical RCU implementation.
[ 0.000000] rcu: RCU restricting CPUs from NR_CPUS=8 to nr_cpu_ids=1.
[ 0.000000] rcu: RCU debug extended QS entry/exit.
[ 0.000000] Tracing variant of Tasks RCU enabled.
[ 0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies.
[ 0.000000] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=1
[ 0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
[ 0.000000] riscv-intc: 64 local interrupts mapped
[ 0.000000] plic: plic@c000000: mapped 53 interrupts with 1 handlers for 2 contexts.
[ 0.000000] random: get_random_bytes called from start_kernel+0x4be/0x71a with crng_init=0
[ 0.000000] riscv_timer_init_dt: Registering clocksource cpuid [0] hartid [0]
[ 0.000000] clocksource: riscv_clocksource: mask: 0xffffffffffffffff max_cycles: 0x24e6a1710, max_idle_ns: 440795202120 ns
[ 0.000110] sched_clock: 64 bits at 10MHz, resolution 100ns, wraps every 4398046511100ns
[ 0.005548] Console: colour dummy device 80x25
[ 0.010694] Calibrating delay loop (skipped), value calculated using timer frequency.. 20.00 BogoMIPS (lpj=40000)
[ 0.010903] pid_max: default: 32768 minimum: 301
[ 0.014081] Mount-cache hash table entries: 512 (order: 0, 4096 bytes, linear)
[ 0.014137] Mountpoint-cache hash table entries: 512 (order: 0, 4096 bytes, linear)
[ 0.045919] cblist_init_generic: Setting adjustable number of callback queues.
[ 0.046122] cblist_init_generic: Setting shift to 0 and lim to 1.
[ 0.046833] ASID allocator using 16 bits (65536 entries)
[ 0.048191] rcu: Hierarchical SRCU implementation.
[ 0.050214] EFI services will not be available.
[ 0.052914] smp: Bringing up secondary CPUs ...
[ 0.053035] smp: Brought up 1 node, 1 CPU
[ 0.064892] devtmpfs: initialized
[ 0.072338] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns
[ 0.072854] futex hash table entries: 256 (order: 2, 16384 bytes, linear)
[ 0.078634] NET: Registered PF_NETLINK/PF_ROUTE protocol family
[ 0.084802] cpuidle: using governor menu
[ 0.116094] HugeTLB registered 2.00 MiB page size, pre-allocated 0 pages
[ 0.121303] iommu: Default domain type: Translated
[ 0.121359] iommu: DMA domain TLB invalidation policy: strict mode
[ 0.122808] SCSI subsystem initialized
[ 0.124731] usbcore: registered new interface driver usbfs
[ 0.125085] usbcore: registered new interface driver hub
[ 0.125244] usbcore: registered new device driver usb
[ 0.139845] vgaarb: loaded
[ 0.141481] clocksource: Switched to clocksource riscv_clocksource
[ 0.160052] NET: Registered PF_INET protocol family
[ 0.161357] IP idents hash table entries: 4096 (order: 3, 32768 bytes, linear)
[ 0.165568] tcp_listen_portaddr_hash hash table entries: 128 (order: 0, 5120 bytes, linear)
[ 0.165859] TCP established hash table entries: 2048 (order: 2, 16384 bytes, linear)
[ 0.166095] TCP bind hash table entries: 2048 (order: 4, 65536 bytes, linear)
[ 0.166331] TCP: Hash tables configured (established 2048 bind 2048)
[ 0.168312] UDP hash table entries: 256 (order: 2, 24576 bytes, linear)
[ 0.168666] UDP-Lite hash table entries: 256 (order: 2, 24576 bytes, linear)
[ 0.170129] NET: Registered PF_UNIX/PF_LOCAL protocol family
[ 0.173256] RPC: Registered named UNIX socket transport module.
[ 0.173403] RPC: Registered udp transport module.
[ 0.173427] RPC: Registered tcp transport module.
[ 0.173453] RPC: Registered tcp NFSv4.1 backchannel transport module.
[ 0.173613] PCI: CLS 0 bytes, default 64
[ 0.180799] workingset: timestamp_bits=62 max_order=16 bucket_order=0
[ 0.195702] NFS: Registering the id_resolver key type
[ 0.196803] Key type id_resolver registered
[ 0.196859] Key type id_legacy registered
[ 0.197434] nfs4filelayout_init: NFSv4 File Layout Driver Registering...
[ 0.197557] nfs4flexfilelayout_init: NFSv4 Flexfile Layout Driver Registering...
[ 0.198259] 9p: Installing v9fs 9p2000 file system support
[ 0.199780] NET: Registered PF_ALG protocol family
[ 0.200339] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 250)
[ 0.200507] io scheduler mq-deadline registered
[ 0.200597] io scheduler kyber registered
[ 0.210780] pci-host-generic 30000000.pci: host bridge /soc/pci@30000000 ranges:
[ 0.211790] pci-host-generic 30000000.pci: IO 0x0003000000..0x000300ffff -> 0x0000000000
[ 0.212339] pci-host-generic 30000000.pci: MEM 0x0040000000..0x007fffffff -> 0x0040000000
[ 0.212418] pci-host-generic 30000000.pci: MEM 0x0400000000..0x07ffffffff -> 0x0400000000
[ 0.213009] pci-host-generic 30000000.pci: Memory resource size exceeds max for 32 bits
[ 0.214178] pci-host-generic 30000000.pci: ECAM at [mem 0x30000000-0x3fffffff] for [bus 00-ff]
[ 0.215635] pci-host-generic 30000000.pci: PCI host bridge to bus 0000:00
[ 0.215922] pci_bus 0000:00: root bus resource [bus 00-ff]
[ 0.216027] pci_bus 0000:00: root bus resource [io 0x0000-0xffff]
[ 0.216104] pci_bus 0000:00: root bus resource [mem 0x40000000-0x7fffffff]
[ 0.216122] pci_bus 0000:00: root bus resource [mem 0x400000000-0x7ffffffff]
[ 0.217645] pci 0000:00:00.0: [1b36:0008] type 00 class 0x060000
[ 0.293879] Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled
[ 0.302601] printk: console [ttyS0] disabled
[ 0.304582] 10000000.uart: ttyS0 at MMIO 0x10000000 (irq = 2, base_baud = 230400) is a 16550A
[ 0.327092] printk: console [ttyS0] enabled
[ 0.343852] loop: module loaded
[ 0.347926] virtio_blk virtio0: [vda] 2097152 512-byte logical blocks (1.07 GB/1.00 GiB)
[ 0.372012] e1000e: Intel(R) PRO/1000 Network Driver
[ 0.372155] e1000e: Copyright(c) 1999 - 2015 Intel Corporation.
[ 0.372587] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
[ 0.372811] ehci-pci: EHCI PCI platform driver
[ 0.373121] ehci-platform: EHCI generic platform driver
[ 0.373489] ohci_hcd: USB 1.1 'Open' Host Controller (OHCI) Driver
[ 0.373714] ohci-pci: OHCI PCI platform driver
[ 0.374048] ohci-platform: OHCI generic platform driver
[ 0.375168] usbcore: registered new interface driver uas
[ 0.375509] usbcore: registered new interface driver usb-storage
[ 0.376576] mousedev: PS/2 mouse device common for all mice
[ 0.380046] goldfish_rtc 101000.rtc: registered as rtc0
[ 0.380819] goldfish_rtc 101000.rtc: setting system clock to 2022-08-19T12:22:18 UTC (1660911738)
[ 0.383918] syscon-poweroff soc:poweroff: pm_power_off already claimed for sbi_srst_power_off
[ 0.384279] syscon-poweroff: probe of soc:poweroff failed with error -16
[ 0.385888] sdhci: Secure Digital Host Controller Interface driver
[ 0.386097] sdhci: Copyright(c) Pierre Ossman
[ 0.386425] sdhci-pltfm: SDHCI platform and OF driver helper
[ 0.387522] usbcore: registered new interface driver usbhid
[ 0.387713] usbhid: USB HID core driver
[ 0.388131] riscv-pmu-sbi: SBI PMU extension is available
[ 0.388784] riscv-pmu-sbi: 15 firmware and 2 hardware counters
[ 0.389008] riscv-pmu-sbi: Perf sampling/filtering is not supported as sscof extension is not available
[ 0.393847] NET: Registered PF_INET6 protocol family
[ 0.400899] Segment Routing with IPv6
[ 0.401209] In-situ OAM (IOAM) with IPv6
[ 0.401878] sit: IPv6, IPv4 and MPLS over IPv4 tunneling driver
[ 0.405085] NET: Registered PF_PACKET protocol family
[ 0.406670] 9pnet: Installing 9P2000 support
[ 0.407129] Key type dns_resolver registered
[ 0.409166] debug_vm_pgtable: [debug_vm_pgtable ]: Validating architecture page table helpers
[ 0.473625] EXT4-fs (vda): mounted filesystem with ordered data mode. Quota mode: disabled.
[ 0.474143] VFS: Mounted root (ext4 filesystem) on device 254:0.
[ 0.477311] devtmpfs: mounted
[ 0.507212] Freeing unused kernel image (initmem) memory: 2164K
[ 0.508186] Run /sbin/init as init process
Please press Enter to activate this console.
可以看见打印出的启动信息中的 OpenSBI 版本是 v1.0,这是 QEMU v7.0.0 自带的 OpenSBI 版本。根据 QEMU 官方文档,当没有 -bios
这一启动参数时,QEMU 将会加载自带的 OpenSBI firmware。而当使用 -bios none
作为启动参数时,QEMU 就不会自动加载任何 firmware。当使用 -bios <file>
指定了特定文件作为 firmware 时, QEMU 就会加载我们指定的那个 firmware 。
使用我们自己编译的 OpenSBI 引导内核的命令如下:
$ qemu-system-riscv64 -M virt -m 256M -nographic \
-bios qemu-opensbi/build/platform/generic/firmware/fw_jump.bin \
-kernel linux-kernel/arch/riscv/boot/Image \
-drive file=rootfs.img,format=raw,id=hd0 \
-device virtio-blk-device,drive=hd0 \
-append "root=/dev/vda rw console=ttyS0"
此处通过 -bios
参数指定了 OpenSBI 编译出的 fw_jump 类型的 firmware。启动日志如下:
OpenSBI v1.1
____ _____ ____ _____
/ __ \ / ____| _ \_ _|
| | | |_ __ ___ _ __ | (___ | |_) || |
| | | | '_ \ / _ \ '_ \ \___ \| _ < | |
| |__| | |_) | __/ | | |____) | |_) || |_
\____/| .__/ \___|_| |_|_____/|____/_____|
| |
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Platform Name : riscv-virtio,qemu
Platform Features : medeleg
Platform HART Count : 1
Platform IPI Device : aclint-mswi
Platform Timer Device : aclint-mtimer @ 10000000Hz
Platform Console Device : uart8250
Platform HSM Device : ---
Platform Reboot Device : sifive_test
Platform Shutdown Device : sifive_test
Firmware Base : 0x80000000
Firmware Size : 288 KB
Runtime SBI Version : 1.0
Domain0 Name : root
Domain0 Boot HART : 0
Domain0 HARTs : 0*
Domain0 Region00 : 0x0000000002000000-0x000000000200ffff (I)
Domain0 Region01 : 0x0000000080000000-0x000000008007ffff ()
Domain0 Region02 : 0x0000000000000000-0xffffffffffffffff (R,W,X)
Domain0 Next Address : 0x0000000080200000
Domain0 Next Arg1 : 0x0000000082200000
Domain0 Next Mode : S-mode
Domain0 SysReset : yes
Boot HART ID : 0
Boot HART Domain : root
Boot HART Priv Version : v1.10
Boot HART Base ISA : rv64imafdch
Boot HART ISA Extensions : time
Boot HART PMP Count : 16
Boot HART PMP Granularity : 4
Boot HART PMP Address Bits: 54
Boot HART MHPM Count : 0
Boot HART MIDELEG : 0x0000000000001666
Boot HART MEDELEG : 0x0000000000f0b509
[ 0.000000] Linux version 5.18.0 (yjmstr@yjmstr) (riscv64-linux-gnu-gcc (Ubuntu 11.2.0-16ubuntu1) 11.2.0, GNU ld (GNU Binutils for Ubuntu) 2.38) #2 SMP Sun Aug 14 13:14:26 CST 2022
[ 0.000000] OF: fdt: Ignoring memory range 0x80000000 - 0x80200000
[ 0.000000] Machine model: riscv-virtio,qemu
[ 0.000000] efi: UEFI not found.
[ 0.000000] Zone ranges:
[ 0.000000] DMA32 [mem 0x0000000080200000-0x000000008fffffff]
[ 0.000000] Normal empty
[ 0.000000] Movable zone start for each node
[ 0.000000] Early memory node ranges
[ 0.000000] node 0: [mem 0x0000000080200000-0x000000008fffffff]
[ 0.000000] Initmem setup node 0 [mem 0x0000000080200000-0x000000008fffffff]
[ 0.000000] SBI specification v1.0 detected
[ 0.000000] SBI implementation ID=0x1 Version=0x10001
[ 0.000000] SBI TIME extension detected
[ 0.000000] SBI IPI extension detected
[ 0.000000] SBI RFENCE extension detected
[ 0.000000] SBI SRST extension detected
[ 0.000000] SBI HSM extension detected
[ 0.000000] riscv: base ISA extensions acdfhim
[ 0.000000] riscv: ELF capabilities acdfim
[ 0.000000] percpu: Embedded 18 pages/cpu s34040 r8192 d31496 u73728
[ 0.000000] Built 1 zonelists, mobility grouping on. Total pages: 64135
[ 0.000000] Kernel command line: root=/dev/vda rw console=ttyS0
[ 0.000000] Dentry cache hash table entries: 32768 (order: 6, 262144 bytes, linear)
[ 0.000000] Inode-cache hash table entries: 16384 (order: 5, 131072 bytes, linear)
[ 0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
[ 0.000000] Virtual kernel memory layout:
[ 0.000000] fixmap : 0xff1bfffffee00000 - 0xff1bffffff000000 (2048 kB)
[ 0.000000] pci io : 0xff1bffffff000000 - 0xff1c000000000000 ( 16 MB)
[ 0.000000] vmemmap : 0xff1c000000000000 - 0xff20000000000000 (1073741824 MB)
[ 0.000000] vmalloc : 0xff20000000000000 - 0xff60000000000000 (17179869184 MB)
[ 0.000000] lowmem : 0xff60000000000000 - 0xff6000000fe00000 ( 254 MB)
[ 0.000000] kernel : 0xffffffff80000000 - 0xffffffffffffffff (2047 MB)
[ 0.000000] Memory: 237564K/260096K available (6460K kernel code, 4865K rwdata, 2048K rodata, 2165K init, 334K bss, 22532K reserved, 0K cma-reserved)
[ 0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
[ 0.000000] rcu: Hierarchical RCU implementation.
[ 0.000000] rcu: RCU restricting CPUs from NR_CPUS=8 to nr_cpu_ids=1.
[ 0.000000] rcu: RCU debug extended QS entry/exit.
[ 0.000000] Tracing variant of Tasks RCU enabled.
[ 0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies.
[ 0.000000] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=1
[ 0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
[ 0.000000] riscv-intc: 64 local interrupts mapped
[ 0.000000] plic: plic@c000000: mapped 53 interrupts with 1 handlers for 2 contexts.
[ 0.000000] random: get_random_bytes called from start_kernel+0x4be/0x71a with crng_init=0
[ 0.000000] riscv_timer_init_dt: Registering clocksource cpuid [0] hartid [0]
[ 0.000000] clocksource: riscv_clocksource: mask: 0xffffffffffffffff max_cycles: 0x24e6a1710, max_idle_ns: 440795202120 ns
[ 0.000111] sched_clock: 64 bits at 10MHz, resolution 100ns, wraps every 4398046511100ns
[ 0.005518] Console: colour dummy device 80x25
[ 0.010392] Calibrating delay loop (skipped), value calculated using timer frequency.. 20.00 BogoMIPS (lpj=40000)
[ 0.010596] pid_max: default: 32768 minimum: 301
[ 0.013666] Mount-cache hash table entries: 512 (order: 0, 4096 bytes, linear)
[ 0.013719] Mountpoint-cache hash table entries: 512 (order: 0, 4096 bytes, linear)
[ 0.045715] cblist_init_generic: Setting adjustable number of callback queues.
[ 0.045930] cblist_init_generic: Setting shift to 0 and lim to 1.
[ 0.046678] ASID allocator using 16 bits (65536 entries)
[ 0.047947] rcu: Hierarchical SRCU implementation.
[ 0.050035] EFI services will not be available.
[ 0.052640] smp: Bringing up secondary CPUs ...
[ 0.052761] smp: Brought up 1 node, 1 CPU
[ 0.064569] devtmpfs: initialized
[ 0.072062] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns
[ 0.072424] futex hash table entries: 256 (order: 2, 16384 bytes, linear)
[ 0.078307] NET: Registered PF_NETLINK/PF_ROUTE protocol family
[ 0.084426] cpuidle: using governor menu
[ 0.114553] HugeTLB registered 2.00 MiB page size, pre-allocated 0 pages
[ 0.120275] iommu: Default domain type: Translated
[ 0.120336] iommu: DMA domain TLB invalidation policy: strict mode
[ 0.121627] SCSI subsystem initialized
[ 0.123678] usbcore: registered new interface driver usbfs
[ 0.124019] usbcore: registered new interface driver hub
[ 0.124451] usbcore: registered new device driver usb
[ 0.138626] vgaarb: loaded
[ 0.140390] clocksource: Switched to clocksource riscv_clocksource
[ 0.159138] NET: Registered PF_INET protocol family
[ 0.160529] IP idents hash table entries: 4096 (order: 3, 32768 bytes, linear)
[ 0.164755] tcp_listen_portaddr_hash hash table entries: 128 (order: 0, 5120 bytes, linear)
[ 0.165042] TCP established hash table entries: 2048 (order: 2, 16384 bytes, linear)
[ 0.165279] TCP bind hash table entries: 2048 (order: 4, 65536 bytes, linear)
[ 0.165513] TCP: Hash tables configured (established 2048 bind 2048)
[ 0.167469] UDP hash table entries: 256 (order: 2, 24576 bytes, linear)
[ 0.167823] UDP-Lite hash table entries: 256 (order: 2, 24576 bytes, linear)
[ 0.169282] NET: Registered PF_UNIX/PF_LOCAL protocol family
[ 0.172534] RPC: Registered named UNIX socket transport module.
[ 0.172606] RPC: Registered udp transport module.
[ 0.172627] RPC: Registered tcp transport module.
[ 0.172642] RPC: Registered tcp NFSv4.1 backchannel transport module.
[ 0.172794] PCI: CLS 0 bytes, default 64
[ 0.180445] workingset: timestamp_bits=62 max_order=16 bucket_order=0
[ 0.194614] NFS: Registering the id_resolver key type
[ 0.195717] Key type id_resolver registered
[ 0.195772] Key type id_legacy registered
[ 0.196382] nfs4filelayout_init: NFSv4 File Layout Driver Registering...
[ 0.196504] nfs4flexfilelayout_init: NFSv4 Flexfile Layout Driver Registering...
[ 0.197282] 9p: Installing v9fs 9p2000 file system support
[ 0.198830] NET: Registered PF_ALG protocol family
[ 0.199384] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 250)
[ 0.199551] io scheduler mq-deadline registered
[ 0.199638] io scheduler kyber registered
[ 0.211458] pci-host-generic 30000000.pci: host bridge /soc/pci@30000000 ranges:
[ 0.212538] pci-host-generic 30000000.pci: IO 0x0003000000..0x000300ffff -> 0x0000000000
[ 0.213088] pci-host-generic 30000000.pci: MEM 0x0040000000..0x007fffffff -> 0x0040000000
[ 0.213169] pci-host-generic 30000000.pci: MEM 0x0400000000..0x07ffffffff -> 0x0400000000
[ 0.213761] pci-host-generic 30000000.pci: Memory resource size exceeds max for 32 bits
[ 0.214890] pci-host-generic 30000000.pci: ECAM at [mem 0x30000000-0x3fffffff] for [bus 00-ff]
[ 0.216401] pci-host-generic 30000000.pci: PCI host bridge to bus 0000:00
[ 0.216695] pci_bus 0000:00: root bus resource [bus 00-ff]
[ 0.216802] pci_bus 0000:00: root bus resource [io 0x0000-0xffff]
[ 0.216882] pci_bus 0000:00: root bus resource [mem 0x40000000-0x7fffffff]
[ 0.216900] pci_bus 0000:00: root bus resource [mem 0x400000000-0x7ffffffff]
[ 0.218331] pci 0000:00:00.0: [1b36:0008] type 00 class 0x060000
[ 0.294377] Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled
[ 0.303136] printk: console [ttyS0] disabled
[ 0.305194] 10000000.uart: ttyS0 at MMIO 0x10000000 (irq = 2, base_baud = 230400) is a 16550A
[ 0.331363] printk: console [ttyS0] enabled
[ 0.348432] loop: module loaded
[ 0.352537] virtio_blk virtio0: [vda] 2097152 512-byte logical blocks (1.07 GB/1.00 GiB)
[ 0.376684] e1000e: Intel(R) PRO/1000 Network Driver
[ 0.376828] e1000e: Copyright(c) 1999 - 2015 Intel Corporation.
[ 0.377400] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
[ 0.377758] ehci-pci: EHCI PCI platform driver
[ 0.378200] ehci-platform: EHCI generic platform driver
[ 0.378530] ohci_hcd: USB 1.1 'Open' Host Controller (OHCI) Driver
[ 0.378801] ohci-pci: OHCI PCI platform driver
[ 0.379167] ohci-platform: OHCI generic platform driver
[ 0.380468] usbcore: registered new interface driver uas
[ 0.380919] usbcore: registered new interface driver usb-storage
[ 0.382100] mousedev: PS/2 mouse device common for all mice
[ 0.385879] goldfish_rtc 101000.rtc: registered as rtc0
[ 0.386647] goldfish_rtc 101000.rtc: setting system clock to 2022-08-19T12:20:44 UTC (1660911644)
[ 0.389614] syscon-poweroff soc:poweroff: pm_power_off already claimed for sbi_srst_power_off
[ 0.389962] syscon-poweroff: probe of soc:poweroff failed with error -16
[ 0.391492] sdhci: Secure Digital Host Controller Interface driver
[ 0.391720] sdhci: Copyright(c) Pierre Ossman
[ 0.392087] sdhci-pltfm: SDHCI platform and OF driver helper
[ 0.393373] usbcore: registered new interface driver usbhid
[ 0.393604] usbhid: USB HID core driver
[ 0.394074] riscv-pmu-sbi: SBI PMU extension is available
[ 0.394764] riscv-pmu-sbi: 16 firmware and 2 hardware counters
[ 0.395033] riscv-pmu-sbi: Perf sampling/filtering is not supported as sscof extension is not available
[ 0.399865] NET: Registered PF_INET6 protocol family
[ 0.407267] Segment Routing with IPv6
[ 0.407649] In-situ OAM (IOAM) with IPv6
[ 0.408329] sit: IPv6, IPv4 and MPLS over IPv4 tunneling driver
[ 0.411565] NET: Registered PF_PACKET protocol family
[ 0.413200] 9pnet: Installing 9P2000 support
[ 0.413775] Key type dns_resolver registered
[ 0.415916] debug_vm_pgtable: [debug_vm_pgtable ]: Validating architecture page table helpers
[ 0.504662] EXT4-fs (vda): mounted filesystem with ordered data mode. Quota mode: disabled.
[ 0.505310] VFS: Mounted root (ext4 filesystem) on device 254:0.
[ 0.529887] devtmpfs: mounted
[ 0.559745] Freeing unused kernel image (initmem) memory: 2164K
[ 0.560852] Run /sbin/init as init process
Please press Enter to activate this console.
可以看见打印出的启动信息中 OpenSBI 版本是 v1.1,这是我们自行编译的 OpenSBI 版本。
总结
本文简要介绍了 RISC-V 的启动流程, QEMU 'virt' 平台下 OpenSBI 和 U-Boot 的简单使用, 根文件系统的制作和 Linux 内核的引导,并分析了 QEMU 启动参数有无 -bios
时的不同行为。接下来的文章我们将探索如何通过 U-Boot 来引导和加载 Linux 内核,并结合 QEMU 'virt' 分析 ZSBL 阶段的行为。
参考资料
- Linux Lab 官方手册
- RISC-V UEFI 架构支持详解,第 1 部分 - OpenSBI/U-Boot/UEFI 简介
- RISC-V OpenSBI 快速上手
- QEMU 官方文档
- 在泰晓 Linux 实验盘中构建 QEMU 并引导 openEuler for RISC-V
- 在 QEMU 上运行 RISC-V 64 位版本的 Linux
- RISC-V 启动流程
- RISC-V SBI 官方文档
- OpenSBI Gitee 镜像
- 用 U-boot 来引导 riscv-linux kernel
- QEMU 6.1.0 运行 RISCV64 OpenSBI + U-Boot + Linux
- Booting RISC-V on QEMU
- 构建 riscv 上运行的 linux 系统
标签:0.000000,启动,generic,driver,Boot,RISC,pci,QEMU 来源: https://www.cnblogs.com/YjmStr/p/16697848.html