uboot下ARMv8 EL切换

#include 
#include 
#include 
#include 
ENTRY(armv8_switch_to_el2)
 switch_el x6, 1f, 0f, 0f
0:
 cmp x5, #ES_TO_AARCH64
 b.eq 2f
 /*
  * When loading 32-bit kernel, it will jump
  * to secure firmware again, and never return.
  */
 bl armv8_el2_to_aarch32
2:
 /*
  * x4 is kernel entry point or switch_to_el1
  * if CONFIG_ARMV8_SWITCH_TO_EL1 is defined.
         * When running in EL2 now, jump to the
  * address saved in x4.
  */
 br x4
1: armv8_switch_to_el2_m x4, x5, x6
ENDPROC(armv8_switch_to_el2)
ENTRY(armv8_switch_to_el1)
 switch_el x6, 0f, 1f, 0f
0:
 /* x4 is kernel entry point. When running in EL1
  * now, jump to the address saved in x4.
  */
 br x4
1: armv8_switch_to_el1_m x4, x5, x6
ENDPROC(armv8_switch_to_el1)
WEAK(armv8_el2_to_aarch32)
 ret
ENDPROC(armv8_el2_to_aarch32)