43 lines
951 B
ArmAsm
43 lines
951 B
ArmAsm
/*
|
|
* Utility functions for FEL mode.
|
|
*
|
|
* Copyright (c) 2015 Google, Inc
|
|
*
|
|
* SPDX-License-Identifier: GPL-2.0+
|
|
*/
|
|
|
|
#include <asm-offsets.h>
|
|
#include <config.h>
|
|
#include <asm/system.h>
|
|
#include <linux/linkage.h>
|
|
|
|
ENTRY(save_boot_params)
|
|
ldr r0, =fel_stash
|
|
str sp, [r0, #0]
|
|
str lr, [r0, #4]
|
|
mrs lr, cpsr @ Read CPSR
|
|
str lr, [r0, #8]
|
|
mrc p15, 0, lr, c1, c0, 0 @ Read CP15 SCTLR Register
|
|
str lr, [r0, #12]
|
|
mrc p15, 0, lr, c12, c0, 0 @ Read VBAR
|
|
str lr, [r0, #16]
|
|
mrc p15, 0, lr, c1, c0, 0 @ Read CP15 Control Register
|
|
str lr, [r0, #20]
|
|
b save_boot_params_ret
|
|
ENDPROC(save_boot_params)
|
|
|
|
ENTRY(return_to_fel)
|
|
mov sp, r0
|
|
mov lr, r1
|
|
ldr r0, =fel_stash
|
|
ldr r1, [r0, #20]
|
|
mcr p15, 0, r1, c1, c0, 0 @ Write CP15 Control Register
|
|
ldr r1, [r0, #16]
|
|
mcr p15, 0, r1, c12, c0, 0 @ Write VBAR
|
|
ldr r1, [r0, #12]
|
|
mcr p15, 0, r1, c1, c0, 0 @ Write CP15 SCTLR Register
|
|
ldr r1, [r0, #8]
|
|
msr cpsr, r1 @ Write CPSR
|
|
bx lr
|
|
ENDPROC(return_to_fel)
|