diff options
Diffstat (limited to 'ArmPlatformPkg/Sec/Helper.S')
| -rw-r--r-- | ArmPlatformPkg/Sec/Helper.S | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/ArmPlatformPkg/Sec/Helper.S b/ArmPlatformPkg/Sec/Helper.S index da3b0e033b..61491b5655 100644 --- a/ArmPlatformPkg/Sec/Helper.S +++ b/ArmPlatformPkg/Sec/Helper.S @@ -19,6 +19,7 @@ GCC_ASM_EXPORT(monitor_vector_table) GCC_ASM_EXPORT(return_from_exception)
GCC_ASM_EXPORT(enter_monitor_mode)
GCC_ASM_EXPORT(copy_cpsr_into_spsr)
+GCC_ASM_EXPORT(set_non_secure_mode)
ASM_PFX(monitor_vector_table):
ldr pc, dead
@@ -68,6 +69,18 @@ ASM_PFX(copy_cpsr_into_spsr): msr spsr_cxsf, r0
bx lr
+# Set the Non Secure Mode
+ASM_PFX(set_non_secure_mode):
+ push { r1 }
+ and r0, r0, #0x1f @ Keep only the mode bits
+ mrs r1, spsr @ Read the spsr
+ bic r1, r1, #0x1f @ Clear all mode bits
+ orr r1, r1, r0
+ msr spsr_cxsf, r1 @ write back spsr (may have caused a mode switch)
+ isb
+ pop { r1 }
+ bx lr @ return (hopefully thumb-safe!)
+
dead:
b dead
|