Timesys Getting Started Guide for TI BeagleBone Black


Contents

Introduction

This document will describe in detail both the procedures for booting a Linux kernel image and mounting a root file system over NFS and SD on the TI BeagleBone Black.

Prerequisites

Host Requirements

To properly boot a board using software from Timesys, your host machine must meet the following requirements:

  • Modern GNU/Linux Distribution. While you can use nearly any modern Linux distribution released in the last 24 months, Timesys recommends one of the following:
    • Ubuntu (Most recent release or LTS)
    • Fedora (Most recent release)
  • An internet connection on the Development Host.
  • Root or sudo permission on the Development Host.
  • A copy of the Linux Kernel (uImage-4.14-ts-armv7l) and Root File System (rootfs.tar.gz) for the Target Board downloaded from Factory. These are found in the output directory of your online build, or in the directory build_armv7l-timesys-linux-<libc>/images/ on the command line.
  • If you are booting your root file system over the network, you will need two network cards installed and configured in the Development Host. One to communicate normally with your LAN/WAN while installing host packages, the other to communicate solely with the target board.
  • An available serial port on your Development Host.

Target Requirements

To boot the TI BeagleBone Black, you will need the following items:

  • TI BeagleBone Black
  • Micro SD Card
  • Micro USB Cable or 5V Power Supply
  • USB TTL Serial Cable (Such as the FTDI TTL-232R-3V3)
  • Ethernet Crossover Cable or Ethernet hub/switch and Ethernet Patch Cables

Once you have all of the necessary components, you should perform the following steps:

  1. Connect the USB TTL serial cable to J1. The following connections are relevant:
    Pin Function
    1 GND
    4 RX
    5 TX
  2. Insert the SD card into your host machine. You will be loading your boot files onto this device.
  3. Connect the USB port of the board to the USB port of your workstation if powering the board using the USB cable.
  4. If you are using a cross-over cable, connect the Ethernet port of the BeagleBone Black board to the second Ethernet port of your workstation.
  5. If you are using an Ethernet hub or switch, connect the debug board to the hub with a straight-through Ethernet cable, then connect the hub to the second Ethernet port of your workstation.
  6. If the board draws more power than the USB connecter can handle, it may cycle during the boot process. In this case, connect the 5V power supply to your board.

Preparing the Target

Configuring Serial Communication

The BeagleBone Black uses a serial debug port to communicate with the host machine. The commands discussed in this section are meant to be performed by a privileged user account. This requires the root login or prepending each command with sudo.

Using Minicom

  1. Start minicom on your host machine in configuration mode. As root:

    # minicom -o -s -w

  2. A menu of configuration should appear. Use the Down-arrow key to scroll down and select the Serial port setup option, and press Enter.
  3. Verify that the listed serial port is the same one that is connected to the target board. If it is not, press A, and enter the correct device. This is /dev/ttyUSB0 on most Linux distributions.
  4. Set the Bps/Par/Bits option by pressing the letter E and using the next menu to set the appropriate values. You press the key that corresponds to the value 115200, then press Enter.
  5. Set Hardware flow control to No using the F key.
  6. Set Software flow control to No using the G key.
  7. Press Enter to return to the main configuration menu, and then press Esc to exit this menu.
  8. Reset the board, and wait for a moment. If you do not see output from the board, press Enter several times until you see the prompt. If you do not see any output from the board, and have verified that the serial terminal connection is setup correctly, contact your board vendor.

TIP: If you experience an error similar to Device /dev/ttyUSB0 is locked when starting minicom, it usually means that another process is using the serial port (which is usually another instance of minicom). You can find the process that is currently using the serial port by executing the following:

# fuser /dev/ttyUSB0
/dev/ttyUSB0:         28358

# ps 28358
  PID TTY      STAT  TIME COMMAND
  28923 pts/0    S+    0:00 minicom

This process can also be killed directly with fuser as root. Please use this command with caution:

# fuser -k /dev/ttyUSB0

Using GNU Screen

To quickly connect to a board using Gnu Screen, execute the following:

# screen /dev/ttyUSB0 115200

For more information about using screen, please consult the man page, or view the manual online at http://www.gnu.org/software/screen/manual/screen.html

Configuring the Network Interface

Finding and Changing the MAC Address

The MAC address on the BeagleBone Black is set by the ethaddr environment variable in U-Boot.

If ethaddr is not set, it can be set using the setenv command.

Example

> setenv ethaddr 12:34:56:78:9a:bc

The MAC Address can be found using the printenv command in U-Boot.

Example

> printenv
baudrate=115200
bootfile="uImage-4.14-ts-armv7l"
stdin=serial
stdout=serial
stderr=serial
ethaddr=12:34:56:78:9a:bc

NOTE Once the MAC address has been set, it cannot be changed without destroying the entire U-Boot environment.

Changing the IP Address

The IP address can be set manually by modifying the ipaddr environment variable, or automatically using the dhcp or bootp commands.

Preparing the Host

No additional host setup is required to boot from SD. But, If you prefer NFS booting

Setting up the network

The commands discussed in this section are meant to be performed by a privileged user account. This requires the root login or prepending each command with sudo.

Identify the network adapter connecting the Host to the Target

Timesys only supports direct Ethernet connections from the development Host to the Target board. Ideally, the development Host would have two network adapters; one adapter to connect to your LAN, and one Ethernet card to connect directly to the Target board with a crossover cable or Ethernet hub. If your development Host only has one network interface it must be directly connected to the Target board. The Ethernet adapter connected directly to the target board must be:
  • Configured with a proper static IP address and Subnet Mask.
  • Connected directly to the target board with either a crossover cable or its own Ethernet hub.
From a command prompt issue the command:
# /sbin/ifconfig
Each interface will report its IP address, Subnet Mask, and Default Gateway information:
eth0 Link encap:Ethernet HWaddr 00:19:bb:49:ff:0e      
        inet addr:192.168.3.244 Bcast:192.168.3.255 Mask:255.255.254.0
        inet6 addr: fe80::219:bbff:fe49:ff0e/64 Scope:Link      
        UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1      
        RX packets:57214 errors:0 dropped:0 overruns:0 frame:0      
        TX packets:47272 errors:0 dropped:0 overruns:0 carrier:0
        collisions:0 txqueuelen:1000      
        RX bytes:43109083 (41.1 MB) TX bytes:6308206 (6.0 MB)
        Interrupt:16
eth1 Link encap:Ethernet HWaddr 00:10:b5:4a:c1:a9      
        inet addr:10.0.0.1 Bcast:10.0.0.255 Mask:255.0.0.0      
        UP BROADCAST MULTICAST MTU:1500 Metric:1      
        RX packets:0 errors:0 dropped:0 overruns:0 frame:0      
        TX packets:0 errors:0 dropped:0 overruns:0 carrier:0     
        collisions:0 txqueuelen:1000      
        RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)      
        Interrupt:21 Base address:0x1100
lo  Link encap:Local Loopback      
        inet addr:127.0.0.1 Mask:255.0.0.0      
        inet6 addr: ::1/128 Scope:Host      
        UP LOOPBACK RUNNING MTU:16436 Metric:1      
        RX packets:1974 errors:0 dropped:0 overruns:0 frame:0      
        TX packets:1974 errors:0 dropped:0 overruns:0 carrier:0     
        collisions:0 txqueuelen:0      
        RX bytes:226637 (221.3 KB) TX bytes:226637 (221.3 KB)
Note the IP address and Subnet Mask of the appropriate network connection. You will use this to configure the DHCP server.

Installing the server daemons on the development host

  • On Ubuntu 11.04 and newer:
    # apt-get install xinetd tftp tftpd isc-dhcp-server \
                      nfs-kernel-server portmap
  • On Ubuntu 10.11 and older:
    # apt-get install xinetd tftp tftpd dhcp3-server \
                      nfs-kernel-server portmap
    NOTE: Older versions of Ubuntu use nfs-common and nfs-user-server in place of nfs-kernel-server
  • On Fedora Core:

    # yum install xinetd tftp tftp-server dhcp nfs-utils

Important:

After installing these packages the DHCP server software may start automatically. Having the DHCP server running while you are connected to a LAN can interfere with the operation of other computers. After the DHCP service installs and starts issue these commands to stop the DHCP service and prevent it from starting automatically at boot:

  • To stop the dhcp service:

    • On Ubuntu 11.04 and newer:

      # service isc-dhcp-server stop

    • On Ubuntu 10.11 and older:

      # service dhcp3-server stop

    • On Fedora Core:

      # /etc/init.d/dhcp stop

  • To prevent the service from starting automatically:

    • On Ubuntu 11.04 and newer:

      # chmod 644 /etc/init.d/isc-dhcp-server

    • On Ubuntu 10.11 and older:

      # chmod 644 /etc/init.d/dhcp3-server

    • On Fedora Core:

      1. Click the System Menu
      2. Select Administration
      3. Select Services
      4. Select dhcpd
      5. Click the Customize button
      6. Uncheck Runlevel 2, 3, 4 and 5

Disable SELinux and Firewall on Fedora Core

On Fedora Core, SELinux and the firewall will interfere with many of the services that are needed to work with the target board. These should be disabled before continuing.

Generally Ubuntu does not have these services running by default.

  1. Disable SELinux:

    1. Click the System Menu
    2. Select Administration
    3. Select SELinux Management
    4. Change System Default Enforcing Mode to Disabled

  2. Disable Firewall:

    1. Click the System Menu
    2. Select Administration
    3. Select Services
    4. Select iptables
    5. Click the Customize button
    6. uncheck Runlevel 2, 3, 4 and 5

Setting up DHCP

  1. Edit the dhcpd configuration file:

    • On Ubuntu, edit /etc/dhcp/dhcpd.conf and include the following lines (note: on older versions of Ubuntu this file is at either /etc/dhcp3/dhcpd.conf or /etc/dhcpd.conf):

      subnet 10.0.0.0 netmask 255.0.0.0 {
       host targetboard {
        fixed-address 10.0.0.10;
        hardware ethernet 12:34:56:78:9a:bc;
        option root-path "/full/path/to/rfs";
        filename "uImage-4.14-ts-armv7l";
       }
      }

    • On Fedora Core, edit /etc/dhcpd.conf and include the following lines:

      ddns-update-style ad-hoc;
      subnet 10.0.0.0 netmask 255.0.0.0 {
       host targetboard {
        fixed-address 10.0.0.10;
        hardware ethernet 12:34:56:78:9a:bc;
        option root-path "/full/path/to/rfs";
        next-server 10.0.0.1;
        filename "uImage-4.14-ts-armv7l";
       }
      }

  2. Test the DHCP server on the network card that is connected to your development board. For this example assume eth1. This command will start the DHCP server in the foreground and output any status or error messages to the screen.

    • On Ubuntu up to 12.04 LTS:

      # service dhcp3-server restart

    • On Ubuntu 12.04 LTS and later:

      # service isc-dhcp-server restart

    • On Fedora Core:

      # /usr/sbin/dhcpd -d eth1

    • It is recommended to start the DHCP server in this manner each time you need to boot your Target board.

Setting up TFTP

  1. Edit the xinetd.conf file

    • On Ubuntu, edit /etc/xinetd.conf and add the following lines just above the line that reads includedir /etc/xinetd.d.

      service tftp
      {
       socket_type = dgram
       protocol = udp
       wait = yes
       user = root
       server = /usr/sbin/in.tftpd
       server_args = -s /tftpboot
       disable = no
      }

    • On Fedora Core, the tftp-server package creates a /etc/xinetd.d/tftp file. Edit this file and change the disable line from yes to no. The contents of the file are:

      service tftp
      {
       socket_type     = dgram
       protocol      = udp
       wait       = yes
       user       = root
       server       = /usr/sbin/in.tftpd
       server_args     = -s /tftpboot
       disable      = no
       per_source      = 11
       cps       = 100 2
       flags       = IPv4
      }

  2. Create the /tftpboot folder if it does not exist:

    # mkdir /tftpboot

  3. Copy the kernel image to the /tftpboot directory:

    # cp /path/to/kernel/image/uImage-4.14-ts-armv7l \
                      /tftpboot/uImage-4.14-ts-armv7l

    NOTE Also copy other files that are required for booting, such as a device tree blob, to /tftpboot.

  4. Restart the xinetd server with the following command:

    # /etc/init.d/xinetd restart

  5. Test the TFTP server with the following commands

    # tftp localhost
    tftp> get uImage-4.14-ts-armv7l
    Received 1456898 bytes in 0.4 seconds
    tftp> quit

  6. Set xinetd to start automatically on Fedora Core.

    Ubuntu users will skip this step.

    1. Click the System Menu
    2. Select Administration
    3. Select Services
    4. Select xinetd
    5. Click the Customize button
    6. Check Runlevel 2, 3, 4 and 5

Setting up NFS

  1. As root, extract rootfs.tar.gz to a directory and note the path. This path will be referred to as /full/path/to/rfs in this document.

    # mkdir /full/path/to/rfs
    # cd /full/path/to/rfs
    # sudo tar xvf rootfs.tar.gz

  2. Export this path by editing /etc/exports to include a line similar to the following:

    /full/path/to/rfs 10.0.0.10(rw,no_root_squash)

  3. Restart the NFS services

    • On Ubuntu issue the following commands in order:

      # service portmap stop
      # service nfs-kernel-server stop
      # service portmap start
      # service nfs-kernel-server start
      NOTE: Older versions of Ubuntu use nfs-common and nfs-user-server in place of nfs-kernel-server

    • On Fedora Core:

      # /etc/init.d/nfs restart

  4. Set nfsd to start automatically on Fedora Core. Ubuntu users will skip this step.

    1. Click the System Menu
    2. Select Administration
    3. Select Services
    4. Select NFS
    5. Click the Customize button
    6. Check Runlevel 2, 3, 4 and 5

Booting the Board

Booting via Tftp and NFS

Set Environment Variables

You must set a few environment variables in order to boot the board over TFTP and DHCP. This is done with the setenv and saveenv commands in U-Boot. On the target, set the following environment variables:

Variable Value
bootargs console=ttyS0,115200 ip=${ipaddr} root=/dev/nfs rw nfsroot=${serverip}:/full/path/to/rfs
bootcmd bootp\;tftp 0x88000000 beaglebone_black.dtb\;bootm 0x82000000 - 0x88000000
loadaddr 0x82000000

If you are not using bootp to load the kernel, you must also specify the following values:

Variable Value
serverip 10.0.0.1
ipaddr 10.0.0.10
bootfile uImage-4.14-ts-armv7l
bootargs console=ttyS0,115200 ip=${ipaddr} root=/dev/nfs rw nfsroot=${serverip}:/full/path/to/rfs
bootcmd tftp\;tftp 0x88000000 beaglebone_black.dtb\;bootm 0x82000000 - 0x88000000

Example

> setenv bootargs console=ttyS0,115200 ip=${ipaddr} root=/dev/nfs rw nfsroot=${serverip}:/full/path/to/rfs
> setenv bootcmd  bootp\;tftp 0x88000000 beaglebone_black.dtb\;bootm 0x82000000 - 0x88000000
> setenv loadaddr 0x82000000
> saveenv

Load The Kernel

You can use bootp or tftp to load the kernel. Note that the DHCP server needs to be set up for bootp, and tftp is necessary for both.

Example

> bootp
Speed: 100, full duplex
BOOTP broadcast 1
Using eTSEC1 device
TFTP from server 10.0.0.1; our IP address is 10.0.0.10
Filename 'uImage-4.14-ts-armv7l'.
Load address: 0x82000000
Loading: #################################################################
         #################################################################
         ##################################################
done
Bytes transferred = 2632869 (282ca5 hex)

Load The Device Tree Blob

You can use tftp to load the device tree. The previous bootp command will have set up the interface for you.

Example

> tftp 0x88000000 beaglebone_black.dtb
Speed: 100, full duplex
Using eTSEC1 device
TFTP from server 10.0.0.1; our IP address is 10.0.0.10
Filename 'beaglebone_black.dtb'.
Load address: 0x88000000
Loading: #
done
Bytes transferred = 13395 (3453 hex)

Boot the Kernel

The bootm command is used to boot the kernel. It loads the file that was previously uploaded using the bootp, dhcp, or tftp commands.

Example

>  bootm 0x82000000 - 0x88000000
## Booting kernel from Legacy Image at 00x82000000 ...
   Image Name:   Linux-4.14
   Image Type:   Linux Kernel Image (gzip compressed)
   Data Size:    2632805 Bytes =  2.5 MB
   Load Address: 00000000
   Entry Point:  00000000
   Verifying Checksum ... OK
## Flattened Device Tree blob at 000x88000000
   Booting using the fdt blob at 0x0x88000000
   Uncompressing Kernel Image ... OK
   Loading Device Tree to 007f9000, end 007ff452 ... OK

Booting via SD card

Preparing the Secure Digital Card

The BeagleBone Black boots from an SD card. Some kits may be shipped with one that contains a sample kernel and RFS preloaded. We will be replacing these with the kernel and RFS from Factory. If you are using a blank SD card or have trouble replacing the software on the preloaded one, see Partitioning the SD Card. Otherwise, skip directly to Writing Boot Files to the SD Card.

Before you begin, you should determine the name of your SD card on your host system. To do so:

  1. Connect the SD card to your host system. Many modern systems have SD card slots on the case, or you can purchase a USB SD Card Reader for around $15 US.
  2. Determine the device name of the SD Card. This can be done using dmesg. In the following example, the device is /dev/sdX, which contains one partition sdX1.

    $ dmesg | tail
    [88050.184080] sd 4:0:0:0: [sdX] 1990656 512-byte hardware sectors: (1.01 GB/972 MiB)
    [88050.184821] sd 4:0:0:0: [sdX] Write Protect is off
    [88050.184824] sd 4:0:0:0: [sdX] Mode Sense: 03 00 00 00
    [88050.184827] sd 4:0:0:0: [sdX] Assuming drive cache: write through
    [88050.185575] sd 4:0:0:0: [sdX] 1990656 512-byte hardware sectors: (1.01 GB/972 MiB)
    [88050.186323] sd 4:0:0:0: [sdX] Write Protect is off
    [88050.186325] sd 4:0:0:0: [sdX] Mode Sense: 03 00 00 00
    [88050.186327] sd 4:0:0:0: [sdX] Assuming drive cache: write through
    [88050.186330]  sdX: sdX1

Partitioning the SD card

If you want to use a different SD card or its contents become corrupted, you can use the fdisk tool to create two partitions on your SD card. Please note that all data on the card will be lost upon completion of these steps.
  1. Unmount the partition if it was automounted by using the umount command.
    $ umount /dev/sdX1
  2. As root, run the fdisk utility on the drive.
    $ sudo fdisk /dev/sdX
  3. In fdisk, Delete the existing partition table and create a new one using the o command.
    Command (m for help): o
    Building a new DOS disklabel with disk identifier 0x8b025602.
    Changes will remain in memory only, until you decide to write them.
    After that, of course, the previous content won't be recoverable.
  4. Create a new primary partition using the n command. The first partition will be a FAT partition for storing the boot files. 64 MB is typically more than enough for this purpose.
    Command (m for help): n
    Partition type:
       p   primary (0 primary, 0 extended, 4 free)
       e   extended
    Select (default p): p
    Partition number (1-4, default 1): 1
    First sector (2048-30679039, default 2048):
    Using default value 2048
    Last sector, +sectors or +sizeK,M,G (2048-30679039, default 30679039): +64M
  5. Set the first partition as W95 FAT32 (LBA) using the t command and entering the Hex code c.
    Command (m for help): t
    Selected partition 1
    Hex code (type L to list codes): c

  6. Set the bootable flag on the first partition using the a command.

    Command (m for help): a
    Partition number (1-4): 1

  7. Create a second primary partition using the n command. This partition will be a linux partition for storing the root filesystem. It will fill the rest of the SD card.

    Command (m for help): n
    Command action
       e   extended
       p   primary partition (1-4)
    p
    Partition number (1-4, default 2): 2
    First sector (133120-30679039, default 133120):
    Using default value 18432
    Last sector, +sectors or +sizeK,M,G (133120-30679039, default 30679039):
    Using default value 30679039

  8. Verify that the partition table is correct by using the p command. It should look similar to the following:

    Command (m for help): p                                                         
                                                                                    
    Disk /dev/sdX: 15.7 GB, 15707668480 bytes
    64 heads, 32 sectors/track, 14980 cylinders, total 30679040 sectors
    Units = sectors of 1 * 512 = 512 bytes
    Sector size (logical/physical): 512 bytes / 512 bytes
    I/O size (minimum/optimal): 512 bytes / 512 bytes
    Disk identifier: 0x6eaae8f8

       Device Boot      Start         End      Blocks   Id  System
    /dev/sdX1   *        2048      133119       65536    c  W95 FAT32 (LBA)
    /dev/sdX2          133120    30679039    14773960   83  Linux

  9. This step will destroy all data on the SD Card - Write the partition table to the card using the w command.

    Command (m for help): w
    The partition table has been altered!

    Calling ioctl() to re-read partition table.

    WARNING: If you have created or modified any DOS 6.x
    partitions, please see the fdisk manual page for additional
    information.
    Syncing disks.

  10. Format the first partition of the SD card with a FAT filesystem using the mkfs.vfat tool.

    $ sudo /sbin/mkfs.vfat -n boot /dev/sdX1

  11. Format the second partition using an ext4 filesystem using the mkfs.ext4 tool.

    $ sudo /sbin/mkfs.ext4 -L rfs /dev/sdX2

Writing Boot Files to the SD Card

Once you have a properly partitioned SD card, you can then populate it with the boot files generated by Factory.

  1. The partitions are usually automounted under /media, but if not, you can use the mount command to mount the partition to an arbitrary location.

    $ sudo mount /dev/sdX1 /media/boot
    $ sudo mount /dev/sdX2 /media/rfs

  2. Copy the u-boot MLO and u-boot bootloader images into the vfat partition.

    $ sudo cp MLO /media/boot/
    $ sudo cp u-boot.img /media/boot/

  3. Copy the kernel image into the boot partition.

    $ sudo cp  uImage-4.14-ts-armv7l /media/boot/

  4. Copy the dtbfile, beaglebone_black.dtb into the boot partition.

    $ sudo cp  beaglebone_black.dtb /media/boot/

  5. As root, extract the rootfs.tar.gz archive to the ext4 partition.

    $ sudo tar xzf rootfs.tar.gz -C /media/rfs

  6. Unmount all partitions.

    $ sudo umount /dev/sdX1
    $ sudo umount /dev/sdX2

  7. Remove the card from the host machine, and insert it into the SD card slot on the BeagleBone Black.

  8. Hold down S2, then power up the board by removing power and reapplying it.

Set Environment Variables

You must set a few environment variables in order to boot the board from the SD card. This is done with the setenv and saveenv commands in U-Boot.

On the target, set the following environment variables:

Variable Value
bootargs console=ttyS0,115200 root=/dev/mmcblk0p2 rw rootwait
load_kernel fatload mmc :1 0x82000000 uImage-4.14-ts-armv7l
load_dtb fatload mmc :1 0x88000000 beaglebone_black.dtb
bootcmd mmc rescan\; run load_kernel load_dtb\; bootm 0x82000000 - 0x88000000

Example

> setenv bootargs console=ttyS0,115200 root=/dev/mmcblk0p2 rw rootwait
> setenv load_kernel fatload mmc :1 0x82000000 uImage-4.14-ts-armv7l
> setenv load_dtb fatload mmc :1 0x88000000 beaglebone_black.dtb
> setenv bootcmd mmc rescan\; run load_kernel load_dtb\; bootm 0x82000000 - 0x88000000
> saveenv

Load The Kernel

You can use the mmc subsystem to load the kernel from the SD card.

Example

> mmc rescan
> fatload mmc :1 0x82000000 uImage-4.14-ts-armv7l
reading uImage-4.14-ts-armv7l

3008612 bytes read

Load The Device Tree

You can use the mmc subsystem to load the device tree file (dtb) from the SD card.

Example

> mmc rescan
> fatload mmc :1 0x88000000 beaglebone_black.dtb
reading beaglebone_black.dtb

24612 bytes read

Boot the Kernel

The bootm command is used to boot the kernel. It loads the file that was previously loaded using the fatload command.

Example

> bootm 0x82000000 - 0x88000000
## Booting kernel from Legacy Image at 0x82000000 ..
   Image Name:   Linux-4.14
   Image Type:   ARM Linux Kernel Image (uncompressed)
   Data Size:    3008548 Bytes =  2.9 MB
   Load Address: 80008000
   Entry Point:  80008000
   Verifying Checksum ... OK
   Loading Kernel Image ... OK
## Flattened Device Tree blob at 0x88000000
   Booting using the fdt blob at 0x88000000
   Loading Kernel Image ... OK
OK

Additional Information

Factory Documentation