Dear list, In u-boot-2011.12/arch/powerpc/cpu/mpc85xx/cpu_init_early.c , line 151 void cpu_init_early_f(void) { ... invalidate_tlb(1); ... } The tlb1 has beening invalidated int the line 151, but I don't know when it was validated again. It makes me feel very confused, please help me. Best regards, Xu Yang