xref: /openbmc/u-boot/arch/arm/cpu/arm920t/ep93xx/cpu.c (revision 0649cd0d)
1 /*
2  * Cirrus Logic EP93xx CPU-specific support.
3  *
4  * Copyright (C) 2009 Matthias Kaehlcke <matthias@kaehlcke.net>
5  *
6  * Copyright (C) 2004, 2005
7  * Cory T. Tusar, Videon Central, Inc., <ctusar@videon-central.com>
8  *
9  * SPDX-License-Identifier:	GPL-2.0+
10  */
11 
12 #include <common.h>
13 #include <asm/arch/ep93xx.h>
14 #include <asm/io.h>
15 
16 /* We reset the CPU by generating a 1-->0 transition on DeviceCfg bit 31. */
17 extern void reset_cpu(ulong addr)
18 {
19 	struct syscon_regs *syscon = (struct syscon_regs *)SYSCON_BASE;
20 	uint32_t value;
21 
22 	/* Unlock DeviceCfg and set SWRST */
23 	writel(0xAA, &syscon->sysswlock);
24 	value = readl(&syscon->devicecfg);
25 	value |= SYSCON_DEVICECFG_SWRST;
26 	writel(value, &syscon->devicecfg);
27 
28 	/* Unlock DeviceCfg and clear SWRST */
29 	writel(0xAA, &syscon->sysswlock);
30 	value = readl(&syscon->devicecfg);
31 	value &= ~SYSCON_DEVICECFG_SWRST;
32 	writel(value, &syscon->devicecfg);
33 
34 	/* Dying... */
35 	while (1)
36 		; /* noop */
37 }
38