xref: /OK3568_Linux_fs/u-boot/arch/arm/cpu/sa1100/cpu.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  * (C) Copyright 2002
3*4882a593Smuzhiyun  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
4*4882a593Smuzhiyun  * Marius Groeger <mgroeger@sysgo.de>
5*4882a593Smuzhiyun  *
6*4882a593Smuzhiyun  * (C) Copyright 2002
7*4882a593Smuzhiyun  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
8*4882a593Smuzhiyun  * Alex Zuepke <azu@sysgo.de>
9*4882a593Smuzhiyun  *
10*4882a593Smuzhiyun  * SPDX-License-Identifier:	GPL-2.0+
11*4882a593Smuzhiyun  */
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun /*
14*4882a593Smuzhiyun  * CPU specific code
15*4882a593Smuzhiyun  */
16*4882a593Smuzhiyun 
17*4882a593Smuzhiyun #include <common.h>
18*4882a593Smuzhiyun #include <command.h>
19*4882a593Smuzhiyun #include <asm/system.h>
20*4882a593Smuzhiyun #include <asm/io.h>
21*4882a593Smuzhiyun 
22*4882a593Smuzhiyun static void cache_flush(void);
23*4882a593Smuzhiyun 
cleanup_before_linux(void)24*4882a593Smuzhiyun int cleanup_before_linux (void)
25*4882a593Smuzhiyun {
26*4882a593Smuzhiyun 	/*
27*4882a593Smuzhiyun 	 * this function is called just before we call linux
28*4882a593Smuzhiyun 	 * it prepares the processor for linux
29*4882a593Smuzhiyun 	 *
30*4882a593Smuzhiyun 	 * just disable everything that can disturb booting linux
31*4882a593Smuzhiyun 	 */
32*4882a593Smuzhiyun 
33*4882a593Smuzhiyun 	disable_interrupts ();
34*4882a593Smuzhiyun 
35*4882a593Smuzhiyun 	/* turn off I-cache */
36*4882a593Smuzhiyun 	icache_disable();
37*4882a593Smuzhiyun 	dcache_disable();
38*4882a593Smuzhiyun 
39*4882a593Smuzhiyun 	/* flush I-cache */
40*4882a593Smuzhiyun 	cache_flush();
41*4882a593Smuzhiyun 
42*4882a593Smuzhiyun 	return (0);
43*4882a593Smuzhiyun }
44*4882a593Smuzhiyun 
45*4882a593Smuzhiyun /* flush I/D-cache */
cache_flush(void)46*4882a593Smuzhiyun static void cache_flush (void)
47*4882a593Smuzhiyun {
48*4882a593Smuzhiyun 	unsigned long i = 0;
49*4882a593Smuzhiyun 
50*4882a593Smuzhiyun 	asm ("mcr p15, 0, %0, c7, c5, 0": :"r" (i));
51*4882a593Smuzhiyun }
52*4882a593Smuzhiyun 
53*4882a593Smuzhiyun #define RST_BASE 0x90030000
54*4882a593Smuzhiyun #define RSRR	0x00
55*4882a593Smuzhiyun #define RCSR	0x04
56*4882a593Smuzhiyun 
reset_cpu(ulong addr)57*4882a593Smuzhiyun __attribute__((noreturn)) void reset_cpu(ulong addr __attribute__((unused)))
58*4882a593Smuzhiyun {
59*4882a593Smuzhiyun 	/* repeat endlessly */
60*4882a593Smuzhiyun 	while (1) {
61*4882a593Smuzhiyun 		writel(0, RST_BASE + RCSR);
62*4882a593Smuzhiyun 		writel(1, RST_BASE + RSRR);
63*4882a593Smuzhiyun 	}
64*4882a593Smuzhiyun }
65