平台：Qemu + vexpress-a9
u-boot：u-boot-2019.10
Linux：linux-4.14.13
 
    之前介绍过用Qemu模拟运行uboot，然后从网络启动linux（用Qemu模拟vexpress-a9 （三）--- 实现用u-boot引导Linux内核），下面介绍用Qemu运行uboot，然后将存放在虚拟出来的SD卡里加载linux kernel、设备树，并运行。
    

一、编译uboot

    下载最新的uboot，编译vexpress-a9：
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- vexpress_ca9x4_defconfig

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- menuconfig

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- -j8
    得到编译生成的u-boot

二、编译linux内核

cross_compile=arm-linux-gnueabihf-

make CROSS_COMPILE=$cross_compile ARCH=arm vexpress_defconfig

make CROSS_COMPILE=$cross_compile ARCH=arm menuconfig

make CROSS_COMPILE=$cross_compile ARCH=arm zImage -j4

make CROSS_COMPILE=$cross_compile ARCH=arm dtbs

三、制作SD卡镜像

1、生成一个空的SD卡镜像
dd if=/dev/zero of=uboot.disk bs=1M count=
2、创建GPT分区，下面创建了两个分区，一个用来存放kernel和设备树，另一个存放根文件系统
sgdisk -n ::+10M -c :kernel uboot.disk

sgdisk -n :: -c :rootfs uboot.disk
查看分区：
$ sgdisk -p uboot.disk

Disk uboot.disk:  sectors, 1024.0 MiB

Sector size (logical):  bytes

Disk identifier (GUID): 04963A5B-34CF-4DEE-B610-F40257C45F6D

Partition table holds up to  entries

Main partition table begins at sector  and ends at sector

First usable sector is , last usable sector is

Partitions will be aligned on -sector boundaries

Total free space is  sectors (1007.0 KiB)

Number Start (sector) End (sector) Size Code Name

      10.0 MiB  kernel

      1013.0 MiB  rootfs
3、寻找一个空闲的loop设备
$ losetup -f

/dev/loop16
4、将SD卡镜像映射到loop设备上
sudo losetup /dev/loop16 uboot.disk

sudo partprobe /dev/loop16
此时会看到/dev/loop16p1和/dev/loop16p2两个节点
5、格式化
sudo mkfs.ext4 /dev/loop16p1

sudo mkfs.ext4 /dev/loop16p2
6、挂载
sudo mount -t ext4 /dev/loop16p1 p1/

sudo mount -t ext4 /dev/loop16p2 p2/
7、拷贝文件
sudo cp linux-4.14./arch/arm/boot/zImage p1/

sudo cp linux-4.14./arch/arm/boot/dts/vexpress-v2*.dtb p1/

sudo cp -raf ../rootfs/rootfs/* ./p2
8、umount
sudo umount p1 p2

sudo losetup -d /dev/loop16
 

四、启动uboot

uboot_image=./u-boot-2019.10/u-boot

qemu_path=/home/pengdl/work/Qemu/qemu-4.1./build/arm-softmmu

${qemu_path}/qemu-system-arm \

    -M vexpress-a9 \

    -m 1024M \

    -smp  \

    -nographic \

    -kernel ${uboot_image} \

    -sd ./uboot.disk
启动log
U-Boot 2019.10-g61a73d0f-dirty (Jan   - :: +)

DRAM:  GiB

WARNING: Caches not enabled

Flash:  MiB

MMC: MMC:

*** Warning - bad CRC, using default environment

In: serial

Out: serial

Err: serial

Net: smc911x-

Hit any key to stop autoboot:
默认SD卡就是出于可用状态，也可以用下面的命令查看：
=> mmc dev

switch to partitions #, OK

mmc0 is current device

=> mmc info

Device: MMC

Manufacturer ID: aa

OEM:

Name: QEMU!

Bus Speed:

Mode: SD Legacy

Rd Block Len:

SD version 2.0

High Capacity: No

Capacity:  GiB

Bus Width: -bit

Erase Group Size:  Bytes
查看分区内容：
=> part list mmc

Partition Map for MMC device  -- Partition Type: EFI

Part Start LBA End LBA Name

        Attributes

        Type GUID

        Partition GUID

   0x00000800 0x000057ff "kernel"

        attrs: 0x0000000000000000

        type: 0fc63daf---8e79-3d69d8477de4

        guid: 0de91381-f36c-4ed7-97d9-2fd234dcef93

   0x00005800 0x001fffde "rootfs"

        attrs: 0x0000000000000000

        type: 0fc63daf---8e79-3d69d8477de4

        guid: 6b0004e2-26a1-428e-abfc-f3a648e7419e

=> ls mmc :  或者 ext4ls mmc :

<DIR>  .

<DIR>  ..

<DIR>  lost+found

          zImage

            vexpress-v2p-ca15_a7.dtb

            vexpress-v2p-ca15-tc1.dtb

            vexpress-v2p-ca5s.dtb

            vexpress-v2p-ca9.dtb

=> ls mmc :  或者 ext4ls mmc :

<DIR>  .

<DIR>  ..

<DIR>  lost+found

<DIR>  bin

<DIR>  dev

<DIR>  etc

<DIR>  home

<DIR>  include

<SYM>  init

<DIR>  lib

<SYM>  linuxrc

<DIR>  proc

<DIR>  root

<DIR>  sbin

<DIR>  share

<DIR>  sys

<DIR>  tmp

<DIR>  usr

<DIR>  var

               .ash_history
 

五、加载kernel、设备树

=> load mmc : 0x60008000 zImage  或者ext4load mmc : 0x60008000 zImage

 bytes read in  ms (7.1 MiB/s)

=> load mmc : 0x61000000 vexpress-v2p-ca9.dtb  或者 ext4load mmc : 0x61000000 vexpress-v2p-ca9.dtb

 bytes read in  ms (213.9 KiB/s)
 

六、设置bootargs

setenv bootargs 'root=/dev/mmcblk0p2 rw rootfstype=ext4 rootwait earlycon console=tty0 console=ttyAMA0 init=/linuxrc ignore_loglevel'
 

七、引导内核

=> bootz 0x60008000 - 0x61000000

八、启动信息

=> bootz 0x60008000 - 0x61000000

Kernel image @ 0x60008000 [ 0x000000 - 0x7532d0 ]

## Flattened Device Tree blob at

   Booting using the fdt blob at 0x61000000

   Loading Device Tree to 7fe82000, end 7fe8898f ... OK

Starting kernel ...

Uncompressing Linux... done, booting the kernel.

[ 0.000000] Booting Linux on physical CPU 0x0

[ 0.000000] Linux version 4.14.+ (pengdl@pengdl-dell) (gcc version 7.3.  [linaro-7.3-2018.05 revision d29120a424ecfbc167ef90065c0eeb7f91977701] (Linaro GCC 7.3-2018.05)) # SMP Mon Jan  :: CST

[ 0.000000] CPU: ARMv7 Processor [410fc090] revision  (ARMv7), cr=10c5387d

[ 0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT nonaliasing instruction cache

[ 0.000000] OF: fdt: Machine model: V2P-CA9

[ 0.000000] param_setup_earlycon enter, buf: (null)

[ 0.000000] earlycon: pl11 at MMIO 0x10009000 (options '115200n8')

[ 0.000000] bootconsole [pl11] enabled

[ 0.000000] param_setup_earlycon enter, buf: tty0

[ 0.000000] param_setup_earlycon enter, buf: ttyAMA0

[ 0.000000] debug: ignoring loglevel setting.

[ 0.000000] Memory policy: Data cache writeback

[ 0.000000] On node  totalpages:

[ 0.000000] free_area_init_node: node , pgdat 80d5f300, node_mem_map bf7f9000

[ 0.000000] Normal zone:  pages used for memmap

[ 0.000000] Normal zone:  pages reserved

[ 0.000000] Normal zone:  pages, LIFO batch:

[ 0.000000] CPU: All CPU(s) started in SVC mode.

[ 0.000000] random: fast init done

[ 0.000000] percpu: Embedded  pages/cpu @bf7ac000 s36428 r8192 d20916 u65536

[ 0.000000] pcpu-alloc: s36428 r8192 d20916 u65536 alloc=*

[ 0.000000] pcpu-alloc: []  []  []  []

[ 0.000000] Built  zonelists, mobility grouping on. Total pages:

[ 0.000000] Kernel command line: root=/dev/mmcblk0p2 rw rootfstype=ext4 rootwait earlycon console=tty0 console=ttyAMA0 init=/linuxrc ignore_loglevel

[ 0.000000] console_setup enter, str: tty0

[ 0.000000] console_setup enter, str: ttyAMA0

[ 0.000000] log_buf_len individual max cpu contribution:  bytes

[ 0.000000] log_buf_len total cpu_extra contributions:  bytes

[ 0.000000] log_buf_len min size:  bytes

[ 0.000000] log_buf_len:  bytes

[ 0.000000] early log buf free: (%)

[ 0.000000] PID hash table entries:  (order: ,  bytes)

[ 0.000000] Dentry cache hash table entries:  (order: ,  bytes)

[ 0.000000] Inode-cache hash table entries:  (order: ,  bytes)

[ 0.000000] Memory: 1026280K/1048576K available (6144K kernel code, 439K rwdata, 1456K rodata, 4096K init, 170K bss, 22296K reserved, 0K cma-reserved)

[ 0.000000] Virtual kernel memory layout:

[ 0.000000] vector : 0xffff0000 - 0xffff1000 (  kB)

[ 0.000000] fixmap : 0xffc00000 - 0xfff00000 ( kB)

[ 0.000000] vmalloc : 0xc0800000 - 0xff800000 ( MB)

[ 0.000000] lowmem : 0x80000000 - 0xc0000000 ( MB)

[ 0.000000] modules : 0x7f000000 - 0x80000000 (  MB)

[ 0.000000] .text : 0x80008000 - 0x80700000 ( kB)

[ 0.000000] .init : 0x80900000 - 0x80d00000 ( kB)

[ 0.000000] .data : 0x80d00000 - 0x80d6dd48 (  kB)

[ 0.000000] .bss : 0x80d74e2c - 0x80d9f634 (  kB)

[ 0.000000] SLUB: HWalign=, Order=-, MinObjects=, CPUs=, Nodes=

[ 0.000000] Hierarchical RCU implementation.

[ 0.000000] RCU event tracing is enabled.

[ 0.000000] RCU restricting CPUs from NR_CPUS= to nr_cpu_ids=.

[ 0.000000] RCU: Adjusting geometry for rcu_fanout_leaf=, nr_cpu_ids=

[ 0.000000] NR_IRQS: , nr_irqs: , preallocated irqs:

[ 0.000000] GIC CPU mask not found - kernel will fail to boot.

[ 0.000000] GIC CPU mask not found - kernel will fail to boot.

[ 0.000000] L2C: platform modifies aux control register: 0x02020000 -> 0x02420000

[ 0.000000] L2C: DT/platform modifies aux control register: 0x02020000 -> 0x02420000

[ 0.000000] L2C- enabling early BRESP for Cortex-A9

[ 0.000000] L2C- full line of zeros enabled for Cortex-A9

[ 0.000000] L2C- dynamic clock gating disabled, standby mode disabled

[ 0.000000] L2C- cache controller enabled,  ways,  kB

[ 0.000000] L2C-: CACHE_ID 0x410000c8, AUX_CTRL 0x46420001

[ 0.000000] smp_twd: clock not found -

[ 0.000236] sched_clock:  bits at 24MHz, resolution 41ns, wraps every 89478484971ns

[ 0.003014] clocksource: arm,sp804: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns:  ns

[ 0.004034] Failed to initialize '/smb@4000000/motherboard/iofpga@7,00000000/timer@12000': -

[ 0.007878] Console: colour dummy device 80x30

[ 0.009804] console [tty0] enabled

[ 0.010213] Calibrating local timer... .50MHz.

[ 0.063660] Calibrating delay loop... 726.63 BogoMIPS (lpj=)

[ 0.163367] pid_max: default:  minimum:

[ 0.164371] Mount-cache hash table entries:  (order: ,  bytes)

[ 0.164640] Mountpoint-cache hash table entries:  (order: ,  bytes)

[ 0.173301] CPU: Testing write buffer coherency: ok

[ 0.180395] CPU0: thread -, cpu , socket , mpidr

[ 0.184217] Setting up static identity map for 0x60100000 - 0x60100060

[ 0.185567] Hierarchical SRCU implementation.

[ 0.190526] smp: Bringing up secondary CPUs ...

[ 0.195085] smp: Brought up  node,  CPU

[ 0.195340] SMP: Total of  processors activated (726.63 BogoMIPS).

[ 0.195628] CPU: All CPU(s) started in SVC mode.

[ 0.226950] devtmpfs: initialized

[ 0.237195] VFP support v0.: implementor  architecture  part  variant  rev

[ 0.249451] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns:  ns

[ 0.250611] futex hash table entries:  (order: ,  bytes)

[ 0.286424] NET: Registered protocol family

[ 0.289887] DMA: preallocated  KiB pool for atomic coherent allocations

[ 0.411870] cpuidle: using governor ladder

[ 0.412536] hw-breakpoint: debug architecture 0x4 unsupported.

[ 0.413148] Serial: AMBA PL011 UART driver

[ 0.417687] OF: amba_device_add() failed (-) for /memory-controller@100e0000

[ 0.418518] OF: amba_device_add() failed (-) for /memory-controller@100e1000

[ 0.419075] OF: amba_device_add() failed (-) for /watchdog@100e5000

[ 0.428162] .uart: ttyAMA0 at MMIO 0x10009000 (irq = , base_baud = ) is a PL011 rev1

[ 0.429393] console [ttyAMA0] enabled

[ 0.429393] console [ttyAMA0] enabled

[ 0.429830] bootconsole [pl11] disabled

[ 0.429830] bootconsole [pl11] disabled

[ 0.437874] 1000a000.uart: ttyAMA1 at MMIO 0x1000a000 (irq = , base_baud = ) is a PL011 rev1

[ 0.439865] 1000b000.uart: ttyAMA2 at MMIO 0x1000b000 (irq = , base_baud = ) is a PL011 rev1

[ 0.441651] 1000c000.uart: ttyAMA3 at MMIO 0x1000c000 (irq = , base_baud = ) is a PL011 rev1

[ 0.443990] OF: amba_device_add() failed (-) for /smb@/motherboard/iofpga@,/wdt@f000

[ 0.492049] SCSI subsystem initialized

[ 0.494187] libata version 3.00 loaded.

[ 0.495179] usbcore: registered new interface driver usbfs

[ 0.495583] usbcore: registered new interface driver hub

[ 0.496019] usbcore: registered new device driver usb

[ 0.500818] Advanced Linux Sound Architecture Driver Initialized.

[ 0.514158] clocksource: Switched to clocksource arm,sp804

[ 0.661421] NET: Registered protocol family

[ 0.665243] TCP established hash table entries:  (order: ,  bytes)

[ 0.665645] TCP bind hash table entries:  (order: ,  bytes)

[ 0.666075] TCP: Hash tables configured (established  bind )

[ 0.667823] UDP hash table entries:  (order: ,  bytes)

[ 0.668211] UDP-Lite hash table entries:  (order: ,  bytes)

[ 0.669427] NET: Registered protocol family

[ 0.672771] RPC: Registered named UNIX socket transport module.

[ 0.673010] RPC: Registered udp transport module.

[ 0.673167] RPC: Registered tcp transport module.

[ 0.673316] RPC: Registered tcp NFSv4. backchannel transport module.

[ 1.032936] hw perfevents: enabled with armv7_cortex_a9 PMU driver,  counters available

[ 1.039079] workingset: timestamp_bits= max_order= bucket_order=

[ 1.056808] squashfs: version 4.0 (//) Phillip Lougher

[ 1.059624] jffs2: version 2.2. (NAND) © - Red Hat, Inc.

[ 1.062208] 9p: Installing v9fs 9p2000 file system support

[ 1.066233] io scheduler noop registered (default)

[ 1.066479] io scheduler mq-deadline registered

[ 1.066735] io scheduler kyber registered

[ 1.071064] clcd-pl11x .clcd: PL111 designer  rev2 at 0x10020000

[ 1.078507] clcd-pl11x .clcd: /clcd@ hardware, 1024x768@ display

[ 1.161773] Console: switching to colour frame buffer device 128x48

[ 1.167184] clcd-pl11x 1001f000.clcd: PL111 designer  rev2 at 0x1001f000

[ 1.168631] clcd-pl11x 1001f000.clcd: /smb@/motherboard/iofpga@,/clcd@1f000 hardware, 640x480@ display

[ 1.477077] brd: module loaded

[ 1.495912] loop: module loaded

[ 1.500177] .flash: Found  x16 devices at 0x0 in -bit bank. Manufacturer ID 0x000000 Chip ID 0x000000

[ 1.501104] Intel/Sharp Extended Query Table at 0x0031

[ 1.501768] Using buffer write method

[ 1.502266] erase region : offset=0x0,size=0x40000,blocks=

[ 1.504422] .flash: Found  x16 devices at 0x0 in -bit bank. Manufacturer ID 0x000000 Chip ID 0x000000

[ 1.504906] Intel/Sharp Extended Query Table at 0x0031

[ 1.505391] Using buffer write method

[ 1.505629] erase region : offset=0x0,size=0x40000,blocks=

[ 1.505986] Concatenating MTD devices:

[ 1.509464] (): "40000000.flash"

[ 1.511999] (): "40000000.flash"

[ 1.514592] into device "40000000.flash"

[ 1.579495] libphy: Fixed MDIO Bus: probed

[ 1.654665] libphy: smsc911x-mdio: probed

[ 1.659191] smsc911x 4e000000.ethernet eth0: MAC Address: :::::

[ 1.765966] isp1760 4f000000.usb: bus width: , oc: digital

[ 1.777548] isp1760 4f000000.usb: NXP ISP1760 USB Host Controller

[ 1.781625] isp1760 4f000000.usb: new USB bus registered, assigned bus number

[ 1.784568] isp1760 4f000000.usb: Scratch test failed.

[ 1.787257] isp1760 4f000000.usb: can't setup: -19

[ 1.789669] isp1760 4f000000.usb: USB bus  deregistered

[ 1.793814] usbcore: registered new interface driver usb-storage

[ 1.802617] rtc-pl031 .rtc: rtc core: registered pl031 as rtc0

[ 1.806070] IR NEC protocol handler initialized

[ 1.808391] IR RC5(x/sz) protocol handler initialized

[ 1.810806] IR RC6 protocol handler initialized

[ 1.813412] IR JVC protocol handler initialized

[ 1.815587] IR Sony protocol handler initialized

[ 1.817861] IR SANYO protocol handler initialized

[ 1.820138] IR Sharp protocol handler initialized

[ 1.822689] IR MCE Keyboard/mouse protocol handler initialized

[ 1.824910] IR XMP protocol handler initialized

[ 1.832118] mmci-pl18x .mmci: Got CD GPIO

[ 1.834664] mmci-pl18x .mmci: Got WP GPIO

[ 1.838372] mmci-pl18x .mmci: mmc0: PL181 manf  rev0 at 0x10005000 irq , (pio)

[ 1.913351] input: AT Raw Set  keyboard as /devices/platform/smb@/smb@:motherboard/smb@:motherboard:i

ofpga@,/.kmi/serio0/input/input0

[ 1.928777] ledtrig-cpu: registered to indicate activity on CPUs

[ 1.933517] usbcore: registered new interface driver usbhid

[ 1.935808] usbhid: USB HID core driver

[ 1.945013] mmc0: new SD card at address

[ 1.952266] mmcblk0: mmc0: QEMU! 1.00 GiB

[ 1.986464] mmcblk0: p1 p2

[ 1.992031] aaci-pl041 .aaci: ARM AC'97 Interface PL041 rev0 at 0x10004000, irq 30

[ 1.994594] aaci-pl041 .aaci: FIFO  entries

[ 1.997482] oprofile: using arm/armv7-ca9

[ 2.000510] NET: Registered protocol family

[ 2.003305] 9pnet: Installing 9P2000 support

[ 2.005828] Registering SWP/SWPB emulation handler

[ 2.017119] rtc-pl031 .rtc: setting system clock to -- :: UTC ()

[ 2.020519] ALSA device list:

[ 2.022710] #: ARM AC'97 Interface PL041 rev0 at 0x10004000, irq 30

[ 2.025497] Warning: unable to open an initial console.

[ 2.063902] Freeing unused kernel memory: 4096K

[ 2.500280] input: ImExPS/ Generic Explorer Mouse as /devices/platform/smb@/smb@:motherboard/smb@:motherboard:iofpga@,/.kmi/serio1/input/input2

[ 3.017505] EXT4-fs (mmcblk0p2): recovery complete

[ 3.021581] EXT4-fs (mmcblk0p2): mounted filesystem with ordered data mode. Opts: (null)

[ 3.076962] Generic PHY 4e000000.ethernet-ffffffff:: attached PHY driver [Generic PHY] (mii_bus:phy_addr=4e000000.ethernet-ffffffff:, irq=POLL)

[ 3.083703] smsc911x 4e000000.ethernet eth0: SMSC911x/921x identified at 0xc1310000, IRQ: 

Please press Enter to activate this console.

[root@vexpress ]#
[root@vexpress ]# mount
rootfs on / type rootfs (rw)
proc on /proc type proc (rw,relatime)
tmpfs on /tmp type tmpfs (rw,relatime)
sysfs on /sys type sysfs (rw,relatime)
tmpfs on /dev type tmpfs (rw,relatime)
debugfs on /sys/kernel/debug type debugfs (rw,relatime)
devpts on /dev/pts type devpts (rw,relatime,mode=600,ptmxmode=000)
/dev/mmcblk0p2 on /root type ext4 (rw,relatime,data=ordered)
[root@vexpress ]# ls
bin      dev      home     init     linuxrc  root     share    tmp      var
d        etc      include  lib      proc     sbin     sys      usr

完。

 
 
 
 

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