Modifying the kernel command line

Changing the kernel command line will be illustrated with an example.

The kernel command line is at a fixed offset from the start of the DDR address range.

We have chosen this offset to be 0x1000.

On the C6474, C6455 and C6457 the kernel command line is at 0x80001000 and on the C6472 the command line is at 0xe0001000.

Assuming that we load a little endian C6474 kernel image into the DDR we will see the following at a memory location 0x80001000 The addresses can be modified from CCS to change the command line. Notice that the nfsroot=158.218.100.25:/opt/min-root-c6x



Obviously this will change from machine to machine and we can change the location. For this illustration i have a copy of the NFS filesystem in /opt/min-root-new directory so nfsroot will change to 158.218.100.25:/opt/min-root-new

This can be changed as shown below





Similarly we can change other kernel boot parameters. For example we let the EVM obtain an IP address from the DHCP server. If we want to assign a static IP address to the EVM we can poke the memory location after ip= and insert a static IP address of our choice.

After making a change to the kernel command line we should be able to boot up a released kernel image.

NOTE:

An alternative to manipulate memory byte values in the CCS memory browser is to use the java script shown in following steps:

1. Create a text file in the directory where ccs5 is installed, e.g. C:\Program File\Texas Instruments\, containing the expected command line info. 2. Select CCS menu View->scripting console 3. In the script console, type

loadRaw ( ,0," ",32,false)

4. Text file content will be displayed in Memory Browser at.