Linux Kit Quickstart

phyCORE-i.MX35 Getting More Involved

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Select I2C Hardware Bus support.

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Check IMX I2C interface.

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Save your configuration and exit the configuration tool.

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Type:

make ARCH=arm CROSS_COMPILE=arm-1136jfs-linuxgnueabi- uImage

The kernel sources will be compiled and the new kernel will be built. This will take a few minutes. The new kernel will be written to

arch/arm/boot/uImage.

If the process of building the kernel stops with an error, check the values of both ARCH and CROSS_COMPILE.

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Close the terminal window.

In this section you learned how to configure and compile a new kernel.

Now you can add new features to your kernel, or remove features you do not need.

Writing the Kernel into the Target’s Flash

In this passage you will find a description on how to write the newly created kernel into the phyCORE-i.MX35’s flash memory. Before the kernel can be written into the flash, the target will have to download the kernel from a TFTP server. This will be done from the command line of the boot loader.

The kernel will be copied into target’s RAM.

Then you will have to erase the part of the flash where you want to copy the kernel image to. Finally the kernel is written from the RAM to the flash.

In the default configuration you will find four partitions on the target: The first partition contains the boot loader, the second is used to store the boot

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phyCORE-i.MX35 Quick Start Instructions loader settings, the third partition stores the Linux kernel, and the fourth contains the root file system.

The four partitions have the following address ranges:

0xa0000000 - 0xa003ffff (U-Boot)

0xa0040000 - 0xa005ffff (U-Boot Environment)

0xa0060000 - 0xa025ffff (Linux Kernel)

0xa0260000 - 0xa1ffffff (Linux Root File System)

You should never erase the U-Boot partition. If this partition is erased, you won’t be able to start your target anymore.

Refer to the chapter “Installing Linux on the phyCORE-

i.MX35”

for detailed information on how to restore your U-

Boot partition in such a case.

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First open a new terminal window if it is not opened yet.

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Copy the new kernel image to the /tftpboot directory and exit:

cp ~/linux-*/arch/arm/boot/uImage /tftpboot; exit

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Open Microcom and press the RESET button on the target.

You will see the output “Hit any key to stop autoboot.”

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Press any key to stop autoboot.

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phyCORE-i.MX35 Getting More Involved

You can download the kernel from the TFTP server to the target’s

RAM, erase the required flash area, and write the kernel from the

RAM into the flash with just one simple command: update_kernel.

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Type the following command to check your U-Boot settings:

edit /env/config

You will see the configuration file which holds U-Boot’s environment variables.

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phyCORE-i.MX35 Quick Start Instructions

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Make sure that the following values are set in the configuration file: eth0.ipaddr=192.168.3.11 eth0.netmask=255.255.0.0 eth0.serverip=192.168.3.10

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Type CTRL-D to save the settings to the file.

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If you made any changes to the U-Boot environment, type save to write these changes to the U-Boot environment partition, and then press the target’s RESET button. The phyCORE-i.MX35 reboots with the new settings applied. Again, press any key to stop autoboot.

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Type update_kernel nor uImage to download the kernel using TFTP and write it into the target’s flash. The copy process can take up to a minute.

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Press the RESET button on the target to restart the phyCORE-i.MX35 with the new kernel. The target will boot the newly created kernel.

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Close Microcom when the target has successfully finished with booting the kernel and mounting the root file system.

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