52 lines
1.2 KiB
ArmAsm
52 lines
1.2 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-or-later */
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/***************************************************************************
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* Copyright (C) 2015 Tomas Vanek *
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* vanekt@fbl.cz *
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***************************************************************************/
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/*
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Disable watchdog for Kinetis Kx and KVx
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Parameters:
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r0 ... WDOG base (in)
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Used instruction set should work on both Cortex-M4 and M0+
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*/
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.text
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.syntax unified
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.cpu cortex-m0
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.thumb
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/* WDOG registers offsets */
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WDOG_STCTRLH = 0
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WDOG_UNLOCK = 0x0e
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WDOG_KEY1 = 0xc520
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WDOG_KEY2 = 0xd928
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.thumb_func
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start:
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/* WDOG_UNLOCK = 0xC520 */
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ldr r2, =WDOG_KEY1
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strh r2, [r0, WDOG_UNLOCK]
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/* WDOG_UNLOCK = 0xD928 */
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ldr r2, =WDOG_KEY2
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strh r2, [r0, WDOG_UNLOCK]
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/* WDOG_STCTRLH clear bit 0 */
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movs r4, #1
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ldrh r2, [r0, WDOG_STCTRLH]
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bics r2, r4
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strh r2, [r0, WDOG_STCTRLH]
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/* OpenOCD checks exit point address. Jump to the very end. */
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b done
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.pool
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/* Avoid padding at .text segment end. Otherwise exit point check fails. */
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.skip ( . - start + 2) & 2, 0
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done:
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bkpt #0
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.end
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