在上一篇博文中我们用NFS挂载根文件系统的方式启动了系统，接下来我们把移植了Python3的根文件系统固化到NandFlash中，但是由于linux-4.9目前不支持Yaffs2文件系统，所以我们用Jiffs2文件系统。

下面我们分为几部分：

1、移植mtd-utils工具

2、固化根文件系统到NandFlash中

3、支持Telnet

平台

硬件：TQ2440  64MB内存 256MB NandFlash

bootloader：U-Boot 2015.04

kernel：linux-4.9

Python: Python-3.6.0

工具链：arm-none-linux-gnueabi-gcc  4.8.3

一、移植mtd-utils工具

mtd-utils提供了大量的用于操作Flash的工具，这里需要首先下载编译一些依赖包。

zlib-1.2.11

下载： http://files.cnblogs.com/files/pengdonglin137/zlib-1.2.11.tar.gz 或者 mtd-utils-2.0.0.tar.bz2

下面是编译脚本：

1 #!/bin/bash

2 

3 export CC=arm-linux-gcc

4 

5 ../configure --prefix=`pwd`

6         --shared

然后编译make && make install

lzo-2.10

下载 http://files.cnblogs.com/files/pengdonglin137/lzo-2.10.tar.gz 或者 http://www.oberhumer.com/opensource/lzo/download/

编译脚本：

1 #!/bin/bash

2 

3 ../configure --host=arm-linux

4         CC="arm-linux-gcc"

5         --prefix=`pwd`

然后编译make && make install

e2fsprogs-1.43.4

下载 http://files.cnblogs.com/files/pengdonglin137/e2fsprogs-1.43.4.tar.gz 或者 https://sourceforge.net/projects/e2fsprogs/files/latest/download?source=files

编译：

1 #!/bin/bash

2 

3 ../configure --host=arm-linux

4         CC="arm-linux-gcc"

5         --prefix=`pwd`

 编译 make && make install

mtd-utils

下载：http://git.infradead.org/mtd-utils.git 或者 http://files.cnblogs.com/files/pengdonglin137/mtd-utils-v2.tar.gz

编译：

1 ( pengdl@ubuntu | ~/Study/tq2440/MTD_UTILS/mtd-utils-v2 | Remote:True )

2 $./autogen.sh

3 

4 ( pengdl@ubuntu | ~/Study/tq2440/MTD_UTILS/mtd-utils-v2 | Remote:True Ret: 130 @ 22:31:03 )

5 $cd build_tq2440/

6 

7 ( pengdl@ubuntu | ~/Study/tq2440/MTD_UTILS/mtd-utils-v2/build_tq2440 | Remote:True )

8 $./mk.sh 

编译脚本：

 1 #!/bin/bash

 2 

 3 export CC=arm-linux-gcc

 4 export PKG_CONFIG_PATH=$PKG_CONFIG_PATH:/home/pengdl/Study/tq2440/MTD_UTILS/e2fsprogs-1.43.4/build_tq2440/lib/uuid

 5 

 6 ../configure --host=arm-linux

 7         --prefix=`pwd`

 8         LDFLAGS="-L/home/pengdl/Study/tq2440/MTD_UTILS/zlib-1.2.11/build_tq2440/lib

 9         -L/home/pengdl/Study/tq2440/MTD_UTILS/lzo-2.10/build_tq2440/lib

10         -L/home/pengdl/Study/tq2440/MTD_UTILS/e2fsprogs-1.43.4/build_tq2440/lib"

11         CPPFLAGS="-I/home/pengdl/Study/tq2440/MTD_UTILS/zlib-1.2.11/build_tq2440/include

12         -I/home/pengdl/Study/tq2440/MTD_UTILS/lzo-2.10/build_tq2440/include

13         -I/home/pengdl/Study/tq2440/MTD_UTILS/e2fsprogs-1.43.4/build_tq2440/include"

14 

15 make -j4

16 make install

在sbin下面会生成我们需要的工具， 这里我们只要flash_eraseall和flash_erase两个工具， 将这两个工具拷贝到根文件系统的/bin下面。

二、固化根文件系统到NandFlash

先把前一篇博文中生成的rootfs目录进行压缩：

sudo tar -czf rootfs.tar.gz rootfs

然后将rootfs.tar.gz拷贝到根文件系统下面，然后启动系统，烧写系统：

1 flash_eraseall  /dev/mtd5

2 mount -t jffs2 /dev/mtdblock5 /mnt

3 tar -xf rootfs.tar.gz /mnt

4 cd /mnt

5 mv rootfs/* .

6 rm -r rootfs

然后修改uboot的bootargs参数：

noinitrd root=/dev/mtdblock5 rw rootfstype=jffs2 console=ttySAC0,115200n init=/linuxrc

三、支持telnet

参考博文 http://www.cnblogs.com/pengdonglin137/p/5028802.html

四、开机log

  1 U-Boot 2015.04-g5095150 (Dec 21 2015 - 06:17:05)

  2 

  3 CPUID: 32440001

  4 FCLK:      400 MHz

  5 HCLK:      100 MHz

  6 PCLK:       50 MHz

  7 I2C:   ready

  8 DRAM:  64 MiB

  9 WARNING: Caches not enabled

 10 Flash: 0 Bytes

 11 NAND:  256 MiB

 12 In:    serial

 13 Out:   serial

 14 Err:   serial

 15 Net:   dm9000

 16 Hit any key to stop autoboot:  0 

 17 

 18 NAND read: device 0 offset 0x300000, size 0x500000

 19  5242880 bytes read: OK

 20 

 21 NAND read: device 0 offset 0x800000, size 0x100000

 22  1048576 bytes read: OK

 23 ## Booting kernel from Legacy Image at 30008000 ...

 24    Image Name:   Linux-4.9.0+

 25    Created:      2017-04-19  10:07:00 UTC

 26    Image Type:   ARM Linux Kernel Image (uncompressed)

 27    Data Size:    3503832 Bytes = 3.3 MiB

 28    Load Address: 30008000

 29    Entry Point:  30008000

 30    Verifying Checksum ... OK

 31 ## Flattened Device Tree blob at 32000000

 32    Booting using the fdt blob at 0x32000000

 33    Loading Kernel Image ... OK

 34    Loading Device Tree to 33aa6000, end 33aaa62c ... OK

 35 

 36 Starting kernel ...

 37 

 38 Uncompressing Linux... done, booting the kernel.

 39 [    0.000000] Booting Linux on physical CPU 0x0

 40 [    0.000000] Linux version 4.9.0+ (pengdl@ubuntu) (gcc version 4.8.3 20140320 (prerelease) (Sourcery CodeBench Lite 2014.05-29) ) #2 Wed Apr 19 03:06:50 PDT 2017

 41 [    0.000000] CPU: ARM920T [41129200] revision 0 (ARMv4T), cr=c000717f

 42 [    0.000000] CPU: VIVT data cache, VIVT instruction cache

 43 [    0.000000] OF: fdt:Machine model: TQ2440

 44 [    0.000000] Memory policy: Data cache writeback

 45 [    0.000000] DT missing boot CPU MPIDR[23:0], fall back to default cpu_logical_map

 46 [    0.000000] Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 16256

 47 [    0.000000] Kernel command line: noinitrd root=/dev/mtdblock5 rw rootfstype=jffs2  console=ttySAC0,115200n init=/linuxrc

 48 [    0.000000] PID hash table entries: 256 (order: -2, 1024 bytes)

 49 [    0.000000] Dentry cache hash table entries: 8192 (order: 3, 32768 bytes)

 50 [    0.000000] Inode-cache hash table entries: 4096 (order: 2, 16384 bytes)

 51 [    0.000000] Memory: 57900K/65536K available (4729K kernel code, 234K rwdata, 1376K rodata, 204K init, 262K bss, 7636K reserved, 0K cma-reserved)

 52 [    0.000000] Virtual kernel memory layout:

 53 [    0.000000]     vector  : 0xffff0000 - 0xffff1000   (   4 kB)

 54 [    0.000000]     fixmap  : 0xffc00000 - 0xfff00000   (3072 kB)

 55 [    0.000000]     vmalloc : 0xc4800000 - 0xff800000   ( 944 MB)

 56 [    0.000000]     lowmem  : 0xc0000000 - 0xc4000000   (  64 MB)

 57 [    0.000000]     modules : 0xbf000000 - 0xc0000000   (  16 MB)

 58 [    0.000000]       .text : 0xc0008000 - 0xc04a67f0   (4730 kB)

 59 [    0.000000]       .init : 0xc0627000 - 0xc065a000   ( 204 kB)

 60 [    0.000000]       .data : 0xc065a000 - 0xc0694840   ( 235 kB)

 61 [    0.000000]        .bss : 0xc0694840 - 0xc06d60a8   ( 263 kB)

 62 [    0.000000] SLUB: HWalign=32, Order=0-3, MinObjects=0, CPUs=1, Nodes=1

 63 [    0.000000] NR_IRQS:103

 64 [    0.000000] irq: clearing pending status 00000002

 65 [    0.000000] _get_rate: could not find clock xti

 66 [    0.000128] sched_clock: 16 bits at 1000kHz, resolution 1000ns, wraps every 32767500ns

 67 [    0.000262] clocksource: samsung_clocksource_timer: mask: 0xffff max_cycles: 0xffff, max_idle_ns: 29163075 ns

 68 [    0.001283] Console: colour dummy device 80x30

 69 [    0.001485] Calibrating delay loop... 199.47 BogoMIPS (lpj=498688)

 70 [    0.035125] pid_max: default: 32768 minimum: 301

 71 [    0.035715] Mount-cache hash table entries: 1024 (order: 0, 4096 bytes)

 72 [    0.035803] Mountpoint-cache hash table entries: 1024 (order: 0, 4096 bytes)

 73 [    0.039125] CPU: Testing write buffer coherency: ok

 74 [    0.041713] Setting up static identity map for 0x30008200 - 0x30008258

 75 [    0.067192] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 9556302231375000 ns

 76 [    0.067812] pinctrl core: initialized pinctrl subsystem

 77 [    0.071047] NET: Registered protocol family 16

 78 [    0.074165] DMA: preallocated 256 KiB pool for atomic coherent allocations

 79 [    0.096405] cpuidle: using governor ladder

 80 [    0.097029] No ATAGs?

 81 [    0.355694] SCSI subsystem initialized

 82 [    0.357161] usbcore: registered new interface driver usbfs

 83 [    0.357830] usbcore: registered new interface driver hub

 84 [    0.358518] usbcore: registered new device driver usb

 85 [    0.362268] Advanced Linux Sound Architecture Driver Initialized.

86 [ 0.393373] clocksource: Switched