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/* SPDX-License-Identifier: GPL-2.0+ */
/*
* Copyright (C) ASPEED Technology Inc.
*/
#include <asm/arch/scu_ast2500.h>
/* registers for low level init */
#define SCU_PROT_KEY 0x1e6e2000
#define SCU_VGA_HANDSHAKE 0x1e6e2040
#define SCU_HW_STRAP 0x1e6e2070
#define SCU_HW_STRAP_CLR 0x1e6e207c
#define WDT3_CTRL 0x1e78504c
.global lowlevel_init
lowlevel_init:
/* unlock SCU */
ldr r0, =SCU_PROT_KEY
ldr r1, =SCU_UNLOCK_VALUE
str r1, [r0]
/* set BMC FW as DRAM initializer */
ldr r0, =SCU_VGA_HANDSHAKE
ldr r1, [r0]
orr r1, #0x80
str r1, [r0]
/* set PERST# as LPC reset source if eSPI mode is enabled*/
ldr r0, =SCU_HW_STRAP
ldr r1, [r0]
tst r1, #(0x1 << 25)
ldrne r0, =SCU_HW_STRAP_CLR
movne r1, #(0x1 << 14)
strne r1, [r0]
/* disable WDT3 for SPI 3/4 bytes auto-detection */
ldr r0, =WDT3_CTRL
mov r1, #0x0
str r1, [r0]
mov pc, lr
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