Embedded Linux Development Using Yocto Project Cookbook - Second Edition

How it works...

Let's have a look at the linux-wandboard_4.1-2.0.x.bb recipe:

include linux-wandboard.inc                                                       
                                                                                 
DEPENDS += "lzop-native bc-native"                                               
                                                                                 
SRCBRANCH = "4.1-2.0.x-imx"                                                      
SRCREV = "0d698de42426a92e3ba47071f11960aeb91eb349"                              
                                                                                 
COMPATIBLE_MACHINE = "(wandboard)"    

The first interesting thing is the inclusion of linux-wandboard.inc, which we will look into later on.

Then it declares two package dependencies, lzop-native and bc-native. The native part tells us that these are used in the host system, so they are used during the Linux kernel build process. The lzop tool is used to create the CPIO compressed files needed in the initramfs system, which is a system that boots from a memory-based root filesystem, and bc was introduced to avoid a Perl kernel ...