just an idea:
code_ref => 'linux_3.2.40_13q3_uni' should look like -> code_ref => ['linux_3.2.40_13q3_uni']

for that you have to do something like this:
${${$hash{'image'}}{'linux_axp_lpae'}}{'code_ref'}=@{'linux_3.2.40_13q_uni'};