xref: /openbmc/u-boot/arch/arm/cpu/sa1100/cpu.c (revision d66ff4ba)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2002
4  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
5  * Marius Groeger <mgroeger@sysgo.de>
6  *
7  * (C) Copyright 2002
8  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
9  * Alex Zuepke <azu@sysgo.de>
10  */
11 
12 /*
13  * CPU specific code
14  */
15 
16 #include <common.h>
17 #include <command.h>
18 #include <asm/system.h>
19 #include <asm/io.h>
20 
21 static void cache_flush(void);
22 
23 int cleanup_before_linux (void)
24 {
25 	/*
26 	 * this function is called just before we call linux
27 	 * it prepares the processor for linux
28 	 *
29 	 * just disable everything that can disturb booting linux
30 	 */
31 
32 	disable_interrupts ();
33 
34 	/* turn off I-cache */
35 	icache_disable();
36 	dcache_disable();
37 
38 	/* flush I-cache */
39 	cache_flush();
40 
41 	return (0);
42 }
43 
44 /* flush I/D-cache */
45 static void cache_flush (void)
46 {
47 	unsigned long i = 0;
48 
49 	asm ("mcr p15, 0, %0, c7, c5, 0": :"r" (i));
50 }
51 
52 #define RST_BASE 0x90030000
53 #define RSRR	0x00
54 #define RCSR	0x04
55 
56 __attribute__((noreturn)) void reset_cpu(ulong addr __attribute__((unused)))
57 {
58 	/* repeat endlessly */
59 	while (1) {
60 		writel(0, RST_BASE + RCSR);
61 		writel(1, RST_BASE + RSRR);
62 	}
63 }
64