COM iMX25 Bootloader U-Boot

FAQ

Downloads

Console commands

NAND Flash

Nand Flash Read

nand read <SDRAM address> <NAND Flash address> <Bytes>

Example: nand read 80000000 400000 b40000

Description: Copies 11,25MByte from NAND Flash address 0x40_0000 to SDRAM address 0x8000_0000

Nand Flash Erase

nand erase <Block base address> <Bytes>

Example: nand erase 400000 40000

Description: Deletes NAND Flash content from address 0x40_0000 to 0x43_FFFF

Note: The Bytes information needs to be block size aligned!

Nand Flash Write

nand write <SDRAM address> <NAND Flash address> <Bytes>

Example: nand write 80000000 400000 b40000

Description: Cpoies 11,25MByte from SDRAM address 0x8000_0000 to NAND Flash address 0x40_0000

Note: The Bytes information needs to be page size aligned!

Show bad NAND Flash blocks

nand bad

Description: Shows the bad NAND Flash blocks.

Show NAND FLash content

nand dump <NAND Flash address>

Example: nand dump 400000

Description: Shows the content of the specified NAND Flash block

LCD contoller

Show LCD controller settings

lcdinfo

Example:

 Display Resolution: 800 x 480 pixels
 Display Type:       Active Color Display
 Pixel Clock:        22 MHz
 Bits per Pixel:     16 Bits/Pixel
 Pixel Polarity:     Active High
 VSYNC Polarity:     Active Low
 HSYNC Polarity:     Active Low
 Clock Polarity:     Pos. Edge
 Output En Polarity: Active High
 HSYNC Puls Width:   64 Clock Cycles
 HSYNC Back Porch:   86 Clock Cycles
 HSYNC Front Porch:  42 Clock Cycles
 VSYNC Puls Width:   2 Line Cycles
 VSYNC Back Porch:   33 Line Cycles
 VSYNC Front Porch:  10 Line Cycles

GPIO's

Show DHCOM GPIO settings

gpioinfo

Example:

 GPIO_A: Direction = Input
         State     = 0
 GPIO_B: Direction = Input
         State     = 0
 GPIO_C: Direction = Input
         State     = 0
 GPIO_D: Direction = Input
         State     = 0
 GPIO_E: Direction = Input
         State     = 1
 GPIO_F: Direction = Input
         State     = 1
 GPIO_G: Direction = Output
         State     = 1
 GPIO_H: Direction = Input
         State     = 1
 GPIO_I: Direction = Input
         State     = 1
 GPIO_J: Direction = Input
         State     = 1
 GPIO_K: Direction = Input
         State     = 0

SD/MMC Card

Switch between MicroSD and SD Slot

mmcswitch <Slot number>

Example: mmcswitch 2

Description: Switch between SD/MMC Slots: 1 --> SD/MMC Slot, 2 --> MicroSD Slot

Initialize SD/MMC Card

mmcinit

Description: Initialize new inserted SD Card

Filesystem

Show Filesystem information

fatinfo <interface> <device>

Example: fatinfo mmc 1

Interface: MMC
 Device 1: Vendor: Man 094150 Snr 266e068c Rev: 1.0 Prod: AF UD
           Type: Removable Hard Disk
           Capacity: 121.2 MB = 0.1 GB (248320 x 512)
 Partition 1: Filesystem: FAT16 "NO NAME    "

List files

fatls <interface> <device> <directory>

Example 1: fatls mmc 1

Example 2: fatls mmc 1 /folder

Load Files from SD Card to SDRAM

fatload <interface> <device> <SDRAM address> <directory+filename>

Example 1: fatload mmc 1 80100000 nk.gz

Example 2: fatload mmc 1 80100000 /folder/nk.gz

Ethernet

Load File via TFTP to SDRAM

tftp <SDRAM address> <directory+filename>

Example: tftp 80100000 nk.gz

Example TFTP Server: "Winagents TFTP Server Manager"

Note: For TFTP download it is necessary to config the ENV variables "ipaddr" and "serverip"

Ping

ping <IP address>

Example: ping 192.168.55.32

Read PHY register via MII interface

mii dump <PHY address> <PHY register>

Example: mii dump 1 0

Description: Shows PHY control register content.

Environment

Show ENV variables

printenv

bootdelay=0
baudrate=38400
ipaddr=192.168.55.230
serverip=192.168.55.36
gatewayip=192.168.55.36
netmask=255.255.255.0
frias=5
kernel=uImage
bootargs=console=ttymxc0,115200 root=/dev/mmcblk0p2
nandbootwince=update;bootwince 00200000
splashimage=0x000c0000
save_ENV_to_flash=setenv ENVinFlash 1; saveenv
ENVinFlash=1
ethaddr=00:04:a3:34:b6:0d
ethact=FEC0
winceimagetype=nk.gz
winceimagesize=00ba55ee
loadaddr=00200000
bootcmd=run nandbootwince
filesize=212050
Environment size: 449/262140 bytes

Set ENV variables

setenv <ENV name> <ENV value>

Example: setenv ipaddr 192.168.55.2

Note: If you need to edit "bootcmd" it is necessary to insert ";" between the unique commands. You can enter ";" at the command line with "\;".

Save ENV variables

saveenv

Update

Note: See also Bootloader subitem Flash Update.

iMX25_update.bmp file

update

Description: Starts Flash update with "iMX25_update.bmp" file.

Command line

update <type> [filename]

Type:

wince = WinCE image update (default file names nk.gz or nk.bin) + ENV update

linux = Linux image update (default file name uImage) + ENV update (default script file name uImage.env)

flash = Complete flash image update

bootloader = Bootloader update (default file name u-boot.bin)

splash = Bootbitmap update (default file name splash.bmp)

settings = Settings block update (default file name settings.bin)

I2C

List available devices

i2c probe

Valid chip addresses: 00 57 6F
0x5F = DHCOM i.MX25 Core Module EEPROM
0x6F = DHCOM i.MX25 Core Module Real Time Clock

Read

i2c md <I2C address> <I2C register> <Bytes>

Example: i2c md 57 0 10

Description: Reads 10 Bytes from the offset 0.

Write

i2c mw <I2C address> <I2C register> <Value> <Bytes>

Example: i2c mw 57 0 aa 5

Description: Writes 0xaa to 5 Bytes from the offset 0.

OS Boot

WinCE

bootwince <Image address> [debug]

Example: bootwince 200000

Description: The address 0x20_0000 specifies NAND Flash image address. The image is loaded from NAND flash to SDRAM. Next to that u-boot starts WinCE. The "debug" option make sure that the image wouldn't be started after uncompressing.

Note: The Image address could also be an SDRAM address. But it is necessary to copy the Image (via tftp or nand flash commands) to the SDRAM before calling "bootwince".

bootwince tftp

Note: The ENV variables "loadaddr" and "bootfile" needs to be set before calling the command. For *.gz image types the "loadaddr" should be set to 0x8290_0000 and for *.bin images the address should be 0x8100_0000.

Linux

bootm <Kernel address> [arg]

Note: When booting a Linux kernel,‘arg' can be the address of an initrd image.

Unzip

unzip <source address> <destination address>

Example: unzip 82900000 80100000

Note: The unzip command is supporting the gzip file format.

Bitmap

Information

bmp info <Bitmap address>

Image size    : 800 x 480
Bits per pixel: 8
Compression   : 0

Display

bmp display <Bitmap SDRAM address> [x y]

Memory

Display

md[.b, .w, .l] <address> [count]

Example: md.b 80100000 100

Write

mw[.b, .w, .l] <address> <value> [count]

Example: mw.b 80100000 aa 100

Description: Writes the value 0xaa to the next 0x100 bytes from the address 0x8010_0000.

Copy

cp[.b, .w, .l] <source> <destination> <count>

Hardware settings

The Hardware settings could be configured via the DHCOM settings file in flash memory. The file contains the following settings:

Settings Block description:

Settings Name:	Description:	Unit:
VALIDATION_ID	"DH"
DISPLAY_ID	unique ID of Display	user defined

Settings Name: Description: Unit:

VALIDATION_ID = „DH“

DISPLAY_ID = unique ID of Display

LENGTH = Length of the settings block

X_RESOLUTION = Display x resolution pixel

Y_RESOLUTION = Display y resolution pixel

PIXEL_CLOCK = Pixel clock kHz

LCD_CONFIG_REG = LCD Configuration Register à see description

HSW = Horizontal synchronization pulse width pixel clocks

VSW = Vertical synchronisation pulse width line clocks

HFP = Horizontal front porch pixel clocks

HBP = Horizontal back porch pixel clocks

VFP = Vertical front porch line clocks

VBP = Vertical back porch line clocks

DATALINES = count of datalines number of datalines

ACB = AC Bias frequency

ACBI = AC Bias transitions per interrupt

GPIO_DIR = DHCOM GPIO default direction register à see description

GPIO_STATE = DHCOM GPIO default state register à see description

HW_CONFIG_REG = Hardware Configuration Register à see description

Flash Update

The follwing updates are possible with the Bootloader:

Bootloader
Splashimage
Settings
Linux image
WinCE image

Overview

Modes

Automatically Update

(Supported from U-Boot v1.10.0.0 or higher)

Is called after the start of the bootloader. The functionality tries to update the flash content via the DHupdate.ini file. The update mechanism is searching for the update files on the specified storage devices. The update devices must be defined at the settings block (Please have a look at Hardware settings). With the DHupdate.ini file you have the possibility to run more then one updates, e.g. OS image and settings block.

Command line Update

Instruction: "update"
(Supported from U-Boot v1.10.0.0 or higher)

The functionality tries to update the flash content via the DHupdate.ini file. In contrast to Automatically Update the update mechanism is searching on every available storage device for the update files.
Instruction: "update <type> [filename]"
(Supported from U-Boot v1.5.0.0 or higher)

The functionality doesn't use the DHupdate.ini file. It allows only one update and the update mechanism is searching on every available storage device for the update files. With the <type> parameter you have to specify the update type.
The <type> parameter could be specified as follows:
wince = WinCE image update + ENV update

linux = Linux image update + ENV update

Note: If you run linux update, u-boot searches also for an update ENV script. This script modifies the ENV for Linux. The name of the script must be the image name with the ending .env. You can also run an update without an script file. In this case u-boot only updates the image and the ENV remains unchanged.

bootloader = Bootloader update

Note: The ENV in Flash memory is created on the first start of u-boot. If you run a bootloader update and the ENV at the new bootloader has changed, the ENV in Flash memory remains unchanged with the bootloader update. But you could delete the ENV block in flash memory before the update, then u-boot will create the new default ENV at the next start after the bootloader update.

splash = Bootbitmap update

settings = Settings block update

Note: Please have a look at Hardware settings.
The [filename] parameter could be used to specify a non default filename. The default filenames are:
wince = default file names nk.gz or nk.bin

linux = default file name uImage + default script file name uImage.env

bootloader = default file name u-boot.bin

splash = default file name splash.bmp

settings = default file name settings.bin

DHupdate.ini file

The DHupdate.ini file is a text file, which describes the user specified update mechanism.

For DHupdate.ini File Example, please have a look at the Please have a look at Download area.

Note: It is necessary to use UNIX End Of Line conversion!!!

Update progress LED description:

The LED GPIO is activated as soon as update has started. This takes roughly 6 - 8 seconds. If the update was finished without an error, the LED GPIO is deactivated. If an error occurs during the update the LED GPIO begins blinking.

LED error code:

1 LED blinking interval = DHupdate.ini File error (Wrong file content or no valid file found)

2 LED blinking interval = Necessary File for Update not found

3 LED blinking interval = Flash write or erase error

4 LED blinking interval = Wrong OS Image type (e.g. no WinCE *.gz or *.bin file)

5 LED blinking interval = Specified file not valid (e.g. linux *.env file)