bi_tag 44 arch/powerpc/boot/redboot-83xx.c if (bd.bi_tag != 0x42444944) bi_tag 42 arch/powerpc/boot/redboot-8xx.c if (bd.bi_tag != 0x42444944) bi_tag 20 arch/powerpc/boot/redboot.h unsigned int bi_tag; /* Should be 0x42444944 "BDID" */