diff options
Diffstat (limited to 'arch/arm/cpu/armv7/sunxi/fel_utils.S')
| -rw-r--r-- | arch/arm/cpu/armv7/sunxi/fel_utils.S | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/arch/arm/cpu/armv7/sunxi/fel_utils.S b/arch/arm/cpu/armv7/sunxi/fel_utils.S new file mode 100644 index 0000000000..bf0033552d --- /dev/null +++ b/arch/arm/cpu/armv7/sunxi/fel_utils.S @@ -0,0 +1,42 @@ +/* + * 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) |