【EVB-335X-II试用体验】 Yocto环境的建立及Rootfs的构建与使用
前面的文章中已经建立起kernel与bootloader的repo，这篇开始，我们将先建立Yocto编译环境，并编译出基本的rootfs。
Yocto基本meta的获取
我们需要好几个meta与poky
首先需要保证至少有65GB的Free磁盘空间或者更多，创建一个目录：
mkdir Yocto
然后clone各个meta与poky
第一个是meta-bbb：
git clone git://github.com/jumpnow/meta-bbb -b original/jethro
然后是poky与其他的：
git clone git://git.yoctoproject.org/poky.git -b original/jethro git clone git://git.openembedded.org/meta-openembedded -b original/jethro
有了这些后我们就可以开始构建了。
在构建之前，我们需要安装必要的文件与库：
sudo apt-get install gawk wget git-core diffstat unzip texinfo gcc-multilib \
build-essential chrpath socat libsdl1.2-dev xterm
这里面我使用的Ubuntu版本是Ubuntu 14.04 X64， 如果其他老的Ubuntu那么是Yocto官方不支持的，需要自己升级对应的软件包才能用。
创建编译目录
因为Yocto默认就含有AM335X的BSP支持，我们这里就直接使用它的，这里面使用的是BeagleBone的。
建立构建目录
source poky/oe-init-build-env evb335xii_build
然后我们就自动进入到了后面参数的目录中，接下来我们还需要配置。
配置板子
更改conf/local.conf文件：
修改layer
layer相当于是多个recipes的集合，而meta是多个layer的集合，关于这些概念可以看我以前写的博客Yocto tips，或者是到Yocto官方查看文档。
修改文件conf/bblayer.conf
修改后的文件如下所示：
构建系统
我们这里选择使用最小的系统来构建，作为第一个目标，使用的命令如下：
bitbake core-image-minimal
构建完成后类似下图：
构建出来的文件位于：
tmp/deploy/images/beaglebone/
最后的产物如下：
可以看到这里面有uboot与kernel以及rootfs，但是这里的uboot与kernel不适合我们的板子，暂时我们只用rootfs。因为现在板子是默认从nand启动的，为了方便，我们直接使用nfs来使用rootfs。
关于如何搭建nfs server，大家可以参考其他的文章。
NFS启动准备
将前面Yocto编译出来的Rootfs解压到NFS的目录中
首先创建目录：
mkdir evb335xii_mini
然后解压：
tar xf tmp/deploy/images/beaglebone/core-image-minimal-beaglebone.tar.bz2 -C ~/nfs/evb335xii_mini/ && sync
TFTP准备在Ubuntu 14.04中，安装使用tftpd-hpa然后出问题，因此我们使用tftpd和openbsd-init，安装配置过程如下：
sudo apt-get install tftpd tftp openbsd-inetd
然后更改配置文件/etc/inetd.conf, 将里面的路径换成我们的，例如/home/XXX/tftpboot,最好再重启service即可：
sudo service openbsd-inetd restart
最后我们在tftpboot中放入一个文件作为测试：
touch ~/tftpboot/abc
然后测试一下：
同时将uImage拷贝进去。
本地网络的配置
我们将本地的网卡配置成static IP，这样子不需要每一次都去查询：
我们直接使用GUI来配置：
然后确定配置成功：
然后在uboot中ping进行测试，命令如下：
set ipaddr 192.168.1.111;set serverip 192.168.1.100 ping 192.168.1.100
如果是alive即说明OK。
使用TFTP与NFS启动Yocto Rootfs
做好了所有准备工作之后，我们对板子上电，然后启动起来，并让其停留在uboot命令行中，然后我们使用下面命令来启动板子：
set ipaddr 192.168.1.111;set serverip 192.168.1.100 set bootargs 'console=ttyO0,115200n8 ip=192.168.1.111 root=/dev/nfs nfsroot=192.168.1.100:/home/hexiongjun/nfs/evb335xii_mini rootwait' tftp 82000000 uImage; bootm 82000000
需要注意的是那个tftp的地址不能与load地址重合，否则会无法启动。
启动后的log如下：
U-Boot SPL 2014.04-rc2 (Jul 11 2015 - 11:06:52) U-Boot 2014.04-rc2 (Jul 11 2015 - 11:06:52) I2C: ready DRAM: 128 MiB NAND: 256 MiB MMC: OMAP SD/MMC: 0, OMAP SD/MMC: 1 *** Warning - bad CRC, using default environment Net: cpsw Hit any key to stop autoboot: 0 U-Boot# set ipaddr 192.168.1.111;set serverip 192.168.1.100 U-Boot# set bootargs 'console=ttyO0,115200n8 ip=192.168.1.111 root=/dev/nfs nfsroot=192.168.1.100:/home/hexiongjun/nfs/evb335xii_mini rootwait' U-Boot# tftp 82000000 uImage; bootm 82000000 link up on port 0, speed 100, full duplex Using cpsw device TFTP from server 192.168.1.100; our IP address is 192.168.1.111 Filename 'uImage'. Load address: 0x82000000 Loading: ################################################################# ################################################################# ################################################################# ################################################################# ################################################################# ################################################################# ################################################################# ################################################################# ############################################################ 3.3 MiB/s done Bytes transferred = 2966384 (2d4370 hex) ## Booting kernel from Legacy Image at 82000000 ... Image Name: Linux-3.2.0-ga74cead Image Type: ARM Linux Kernel Image (uncompressed) Data Size: 2966320 Bytes = 2.8 MiB Load Address: 80008000 Entry Point: 80008000 Verifying Checksum ... OK Loading Kernel Image ... OK Starting kernel ... [ 0.000000] Linux version 3.2.0-ga74cead (hexiongjun@hexiongjun-i7) (gcc version 4.7.3 (Ubuntu/Linaro 4.7.3-12ubuntu1) ) #1 Sun Jul 24 15:06:31 CST 2016 [ 0.000000] CPU: ARMv7 Processor [413fc082] revision 2 (ARMv7), cr=10c53c7d [ 0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache [ 0.000000] Machine: com335x [ 0.000000] Memory policy: ECC disabled, Data cache writeback [ 0.000000] AM335X ES2.1 (neon ) [ 0.000000] Built 1 zonelists in Zone order, mobility grouping on. Total pages: 32512 [ 0.000000] Kernel command line: console=ttyO0,115200n8 ip=192.168.1.111 root=/dev/nfs nfsroot=192.168.1.100:/home/hexiongjun/nfs/evb335xii_mini rootwait [ 0.000000] PID hash table entries: 512 (order: -1, 2048 bytes) [ 0.000000] Dentry cache hash table entries: 16384 (order: 4, 65536 bytes) [ 0.000000] Inode-cache hash table entries: 8192 (order: 3, 32768 bytes) [ 0.000000] Memory: 128MB = 128MB total [ 0.000000] Memory: 123796k/123796k available, 7276k reserved, 0K highmem [ 0.000000] Virtual kernel memory layout: [ 0.000000] vector : 0xffff0000 - 0xffff1000 ( 4 kB) [ 0.000000] fixmap : 0xfff00000 - 0xfffe0000 ( 896 kB) [ 0.000000] vmalloc : 0xc8800000 - 0xff000000 ( 872 MB) [ 0.000000] lowmem : 0xc0000000 - 0xc8000000 ( 128 MB) [ 0.000000] modules : 0xbf000000 - 0xc0000000 ( 16 MB) [ 0.000000] .text : 0xc0008000 - 0xc0537000 (5308 kB) [ 0.000000] .init : 0xc0537000 - 0xc0571000 ( 232 kB) [ 0.000000] .data : 0xc0572000 - 0xc05c92e8 ( 349 kB) [ 0.000000] .bss : 0xc05c930c - 0xc05f7ee4 ( 187 kB) [ 0.000000] NR_IRQS:396 [ 0.000000] IRQ: Found an INTC at 0xfa200000 (revision 5.0) with 128 interrupts [ 0.000000] Total of 128 interrupts on 1 active controller [ 0.000000] OMAP clockevent source: GPTIMER2 at 24000000 Hz [ 0.000000] omap_dm_timer_switch_src: Switching to HW default clocksource(sys_clkin_ck) for timer1, this may impact timekeeping in low power state [ 0.000000] OMAP clocksource: GPTIMER1 at 24000000 Hz [ 0.000000] sched_clock: 32 bits at 24MHz, resolution 41ns, wraps every 178956ms [ 0.000000] Console: colour dummy device 80x30 [ 0.000187] Calibrating delay loop... 795.44 BogoMIPS (lpj=3977216) [ 0.087382] pid_max: default: 32768 minimum: 301 [ 0.087494] Security Framework initialized [ 0.087588] Mount-cache hash table entries: 512 [ 0.087949] CPU: Testing write buffer coherency: ok [ 0.088674] devtmpfs: initialized [ 0.107938] omap_hwmod: gfx: failed to hardreset [ 0.123811] omap_hwmod: pruss: failed to hardreset [ 0.124868] print_constraints: dummy: [ 0.125221] NET: Registered protocol family 16 [ 0.127347] OMAP GPIO hardware version 0.1 [ 0.129789] omap_mux_init: Add partition: #1: core, flags: 0 [ 0.131636] omap_i2c.1: alias fck already exists [ 0.132286] omap-gpmc omap-gpmc: GPMC revision 6.0 [ 0.132303] Registering NAND on CS0 [ 0.132859] omap_hsmmc.0: alias fck already exists [ 0.134071] d_can.0: alias fck already exists [ 0.134262] com335x: mcasp1 init [ 0.134344] davinci-mcasp.1: alias fck already exists [ 0.134968] omap_i2c.3: alias fck already exists [ 0.135881] omap2_mcspi.1: alias fck already exists [ 0.136106] omap2_mcspi.2: alias fck already exists [ 0.136358] edma.0: alias fck already exists [ 0.136377] edma.0: alias fck already exists [ 0.136394] edma.0: alias fck already exists [ 0.154307] bio: create slab <bio-0> at 0 [ 0.156289] SCSI subsystem initialized [ 0.158123] usbcore: registered new interface driver usbfs [ 0.158416] usbcore: registered new interface driver hub [ 0.158614] usbcore: registered new device driver usb [ 0.158911] registerd cppi-dma Intr @ IRQ 17 [ 0.158924] Cppi41 Init Done Qmgr-base(c887a000) dma-base(c8878000) [ 0.158932] Cppi41 Init Done [ 0.158956] musb-ti81xx musb-ti81xx: musb0, board_mode=0x13, plat_mode=0x3 [ 0.159227] musb-ti81xx musb-ti81xx: musb1, board_mode=0x13, plat_mode=0x1 [ 0.177400] omap_i2c omap_i2c.1: bus 1 rev2.4.0 at 400 kHz [ 0.178046] tps65217 1-0024: TPS65217 ID 0xe version 1.2 [ 0.178963] print_constraints: DCDC1: 900 <--> 1800 mV at 1500 mV [ 0.179932] print_constraints: DCDC2: 900 <--> 3300 mV at 1275 mV [ 0.180875] print_constraints: DCDC3: 900 <--> 1500 mV at 1125 mV [ 0.181794] print_constraints: LDO1: 1000 <--> 3300 mV at 1800 mV [ 0.182717] print_constraints: LDO2: 900 <--> 3300 mV at 3300 mV [ 0.183655] print_constraints: LDO3: 1800 <--> 3300 mV at 1800 mV [ 0.184581] print_constraints: LDO4: 1800 <--> 3300 mV at 3300 mV [ 0.197403] omap_i2c omap_i2c.3: bus 3 rev2.4.0 at 400 kHz [ 0.198899] Advanced Linux Sound Architecture Driver Version 1.0.24. [ 0.200060] Switching to clocksource gp timer [ 0.216447] musb-hdrc: version 6.0, ?dma?, otg (peripheral+host) [ 0.216639] musb-hdrc musb-hdrc.0: dma type: dma-cppi41 [ 0.216958] MUSB0 controller's USBSS revision = 4ea20800 [ 0.216988] musb0: Enabled SW babble control [ 0.217829] musb-hdrc musb-hdrc.0: USB OTG mode controller at c884a000 using DMA, IRQ 18 [ 0.217985] musb-hdrc musb-hdrc.1: dma type: dma-cppi41 [ 0.218266] MUSB1 controller's USBSS revision = 4ea20800 [ 0.218291] musb1: Enabled SW babble control [ 0.218694] musb-hdrc musb-hdrc.1: MUSB HDRC host driver [ 0.218798] musb-hdrc musb-hdrc.1: new USB bus registered, assigned bus number 1 [ 0.218923] usb usb1: New USB device found, idVendor=1d6b, idProduct=0002 [ 0.218937] usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1 [ 0.218949] usb usb1: Product: MUSB HDRC host driver [ 0.218958] usb usb1: Manufacturer: Linux 3.2.0-ga74cead musb-hcd [ 0.218968] usb usb1: SerialNumber: musb-hdrc.1 [ 0.219835] hub 1-0:1.0: USB hub found [ 0.219865] hub 1-0:1.0: 1 port detected [ 0.220502] musb-hdrc musb-hdrc.1: USB Host mode controller at c884c800 using DMA, IRQ 19 [ 0.220935] NET: Registered protocol family 2 [ 0.221125] IP route cache hash table entries: 1024 (order: 0, 4096 bytes) [ 0.221391] TCP established hash table entries: 4096 (order: 3, 32768 bytes) [ 0.221470] TCP bind hash table entries: 4096 (order: 2, 16384 bytes) [ 0.221518] TCP: Hash tables configured (established 4096 bind 4096) [ 0.221529] TCP reno registered [ 0.221540] UDP hash table entries: 256 (order: 0, 4096 bytes) [ 0.221560] UDP-Lite hash table entries: 256 (order: 0, 4096 bytes) [ 0.221744] NET: Registered protocol family 1 [ 0.221983] RPC: Registered named UNIX socket transport module. [ 0.221996] RPC: Registered udp transport module. [ 0.222003] RPC: Registered tcp transport module. [ 0.222011] RPC: Registered tcp NFSv4.1 backchannel transport module. [ 0.222222] NetWinder Floating Point Emulator V0.97 (double precision) [ 0.222244] Error: Driver 'omap-gpmc' is already registered, aborting... [ 0.229165] VFS: Disk quotas dquot_6.5.2 [ 0.229231] Dquot-cache hash table entries: 1024 (order 0, 4096 bytes) [ 0.229741] msgmni has been set to 241 [ 0.230512] io scheduler noop registered [ 0.230524] io scheduler deadline registered [ 0.230584] io scheduler cfq registered (default) [ 0.233607] omap_uart.0: ttyO0 at MMIO 0x44e09000 (irq = 72) is a OMAP UART0 [ 0.916776] console [ttyO0] enabled [ 0.921091] omap_uart.1: ttyO1 at MMIO 0x48022000 (irq = 73) is a OMAP UART1 [ 0.928914] omap_uart.2: ttyO2 at MMIO 0x48024000 (irq = 74) is a OMAP UART2 [ 0.936766] omap_uart.3: ttyO3 at MMIO 0x481a6000 (irq = 44) is a OMAP UART3 [ 0.944590] omap_uart.4: ttyO4 at MMIO 0x481a8000 (irq = 45) is a OMAP UART4 [ 0.962212] brd: module loaded [ 0.970242] loop: module loaded [ 0.973605] at24 1-0050: 32768 byte 24c256 EEPROM, writable, 64 bytes/write [ 0.983216] mtdoops: mtd device (mtddev=name/number) must be supplied [ 0.990368] omap2-nand driver initializing [ 0.994963] ONFI flash detected [ 0.998365] ONFI param page 0 valid [ 1.002047] NAND device: Manufacturer ID: 0x2c, Chip ID: 0xda (Micron MT29F2G08ABAEAWP) [ 1.010630] Creating 9 MTD partitions on "omap2-nand.0": [ 1.016194] 0x000000000000-0x000000020000 : "SPL" [ 1.022625] 0x000000020000-0x000000040000 : "SPL.backup1" [ 1.029573] 0x000000040000-0x000000060000 : "SPL.backup2" [ 1.036601] 0x000000060000-0x000000080000 : "SPL.backup3" [ 1.043773] 0x000000080000-0x000000260000 : "U-Boot" [ 1.050965] 0x000000260000-0x000000280000 : "U-Boot Env" [ 1.057774] 0x000000280000-0x000000580000 : "logo" [ 1.065288] 0x000000580000-0x000000a80000 : "Kernel" [ 1.073815] 0x000000a80000-0x000010000000 : "File System" [ 1.181978] OneNAND driver initializing [ 1.187315] CAN device driver interface [ 1.191365] CAN bus driver for Bosch D_CAN controller 1.0 [ 1.197786] d_can d_can.0: device registered (irq=52, irq_obj=53) [ 1.250133] davinci_mdio davinci_mdio.0: davinci mdio revision 1.6 [ 1.256601] davinci_mdio davinci_mdio.0: detected phy mask fffffffe [ 1.263972] davinci_mdio.0: probed [ 1.267532] davinci_mdio davinci_mdio.0: phy[0]: device 0:00, driver SMSC LAN8710/LAN8720 [ 1.276263] PPP generic driver version 2.4.2 [ 1.281177] PPP BSD Compression module registered [ 1.286097] PPP Deflate Compression module registered [ 1.291597] usbcore: registered new interface driver zd1201 [ 1.297595] usbcore: registered new interface driver cdc_ether [ 1.303859] usbcore: registered new interface driver cdc_eem [ 1.309910] usbcore: registered new interface driver dm9601 [ 1.315788] cdc_ncm: 04-Aug-2011 [ 1.319304] usbcore: registered new interface driver cdc_ncm [ 1.325411] usbcore: registered new interface driver cdc_acm [ 1.331340] cdc_acm: USB Abstract Control Model driver for USB modems and ISDN adapters [ 1.339708] Initializing USB Mass Storage driver... [ 1.345018] usbcore: registered new interface driver usb-storage [ 1.351313] USB Mass Storage support registered. [ 1.356464] usbcore: registered new interface driver usbserial [ 1.362711] USB Serial support registered for generic [ 1.368135] usbcore: registered new interface driver usbserial_generic [ 1.374974] usbserial: USB Serial Driver core [ 1.379650] USB Serial support registered for GSM modem (1-port) [ 1.386182] usbcore: registered new interface driver option [ 1.392024] option: v0.7.2:USB Driver for GSM modems [ 1.397762] mousedev: PS/2 mouse device common for all mice [ 1.404273] input: ti-tsc as /devices/platform/omap/ti_tscadc/tsc/input/input0 [ 1.413016] input: ft5x06_ts as /devices/virtual/input/input1 [ 1.471658] rtc-ds1307 1-0068: rtc core: registered ds1339 as rtc0 [ 1.478272] i2c /dev entries driver [ 1.484875] cpuidle: using governor ladder [ 1.489596] cpuidle: using governor menu [ 1.498275] usbcore: registered new interface driver usbhid [ 1.504148] usbhid: USB HID core driver [ 1.508796] tiadc tiadc: attached adc driver [ 1.515476] _regulator_get: 1-001b supply IOVDD not found, using dummy regulator [ 1.523316] _regulator_get: 1-001b supply DVDD not found, using dummy regulator [ 1.531014] _regulator_get: 1-001b supply AVDD not found, using dummy regulator [ 1.538687] _regulator_get: 1-001b supply DRVDD not found, using dummy regulator [ 1.548870] asoc: tlv320aic3x-hifi <-> davinci-mcasp.1 mapping ok [ 1.559602] ALSA device list: [ 1.562764] #0: COM335X EVM [ 1.565863] oprofile: hardware counters not available [ 1.571151] oprofile: using timer interrupt. [ 1.575638] nf_conntrack version 0.5.0 (1934 buckets, 7736 max) [ 1.582280] ip_tables: (C) 2000-2006 Netfilter Core Team [ 1.587943] TCP cubic registered [ 1.591350] NET: Registered protocol family 17 [ 1.596003] can: controller area network core (rev 20090105 abi 8) [ 1.602550] NET: Registered protocol family 29 [ 1.607224] can: raw protocol (rev 20090105) [ 1.611700] can: broadcast manager protocol (rev 20090105 t) [ 1.617652] Registering the dns_resolver key type [ 1.622652] VFP support v0.3: implementor 41 architecture 3 part 30 variant c rev 3 [ 1.630683] ThumbEE CPU extension supported. [ 1.635207] mux: Failed to setup hwmod io irq -22 [ 1.640770] Power Management for AM33XX family [ 1.645420] pm: Err (-22) setting core voltage setting [ 1.651017] Trying to load am335x-pm-firmware.bin (60 secs timeout) [ 1.657683] Copied the M3 firmware to UMEM [ 1.662038] Cortex M3 Firmware Version = 0x184 [ 1.669860] clock: disabling unused clocks to save power [ 1.677483] Detected MACID=ec:24:b8:b1:f2:38 [ 1.683936] rtc-ds1307 1-0068: setting system clock to 2016-07-14 13:50:15 UTC (1468504215) [ 1.695691] net eth0: CPSW phy found : id is : 0x7c0f1 [ 1.701865] PHY 0:01 not found [ 5.690645] PHY: 0:00 - Link is Up - 100/Full [ 5.720110] IP-Config: Guessing netmask 255.255.255.0 [ 5.725532] IP-Config: Complete: [ 5.728905] device=eth0, addr=192.168.1.111, mask=255.255.255.0, gw=255.255.255.255, [ 5.737217] host=192.168.1.111, domain=, nis-domain=(none), [ 5.743507] bootserver=255.255.255.255, rootserver=192.168.1.100, rootpath= [ 5.757059] VFS: Mounted root (nfs filesystem) on device 0:15. [ 5.763600] devtmpfs: mounted [ 5.767031] Freeing init memory: 232K INIT: version 2.88 booting Starting udev [ 6.424949] udevd[654]: starting version 182 bootlogd: cannot allocate pseudo tty: No such file or directory INIT: Entering runlevel: 5 Configuring network interfaces... ifup skipped for nfsroot interface eth0 run-parts: /etc/network/if-pre-up.d/nfsroot exited with code 1 Starting syslogd/klogd: done Poky (Yocto Project Reference Distro) 2.0.2 beaglebone /dev/ttyO0 beaglebone login: root root@beaglebone:~# ———————————————— 版权声明：本文为CSDN博主「TonyHo」的原创文章，遵循CC 4.0 BY-SA版权协议，转载请附上原文出处链接及本声明。 原文链接：https://blog.csdn.net/sy373466062/article/details/52023163
从log中我们可以看到内核的时间，以及rootfs的启动，但是我们发现启动不久后就重启了，那是因为watch dog的原因。
到这里，我们就构建了基本的环境与系统了。我们在接下来的文章中将继续使用Yocto等来构建与开发。
