summaryrefslogtreecommitdiff
path: root/cpu/pxa/cpu.c
blob: 6a3c24dedab399adf1003688d63f777a663cb1db (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
/*
 * (C) Copyright 2002
 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
 * Marius Groeger <mgroeger@sysgo.de>
 *
 * (C) Copyright 2002
 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
 * Alex Zuepke <azu@sysgo.de>
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 */

/*
 * CPU specific code
 */

#include <common.h>
#include <command.h>

int cpu_init (void)
{
	/*
	 * setup up stack if necessary
	 */
/*

  FIXME: the stack is _below_ the uboot code!!

#ifdef CONFIG_USE_IRQ
	IRQ_STACK_START = _armboot_end +
			CONFIG_STACKSIZE + CONFIG_STACKSIZE_IRQ - 4;
	FIQ_STACK_START = IRQ_STACK_START + CONFIG_STACKSIZE_FIQ;
	_armboot_real_end = FIQ_STACK_START + 4;
#else
	_armboot_real_end = _armboot_end + CONFIG_STACKSIZE;
#endif
*/
	return (0);
}

int cleanup_before_linux (void)
{
	/*
	 * this function is called just before we call linux
	 * it prepares the processor for linux
	 *
	 * just disable everything that can disturb booting linux
	 */

	unsigned long i;

	disable_interrupts ();

	/* turn off I-cache */
	asm ("mrc p15, 0, %0, c1, c0, 0":"=r" (i));
	i &= ~0x1000;
	asm ("mcr p15, 0, %0, c1, c0, 0": :"r" (i));

	/* flush I-cache */
	asm ("mcr p15, 0, %0, c7, c5, 0": :"r" (i));

	return (0);
}

int do_reset (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
{
	extern void reset_cpu (ulong addr);

	printf ("reseting ...\n");

	udelay (50000);				/* wait 50 ms */
	disable_interrupts ();
	reset_cpu (0);

	/*NOTREACHED*/
	return (0);
}

/* taken from blob */
void icache_enable (void)
{
	register u32 i;

	/* read control register */
	asm ("mrc p15, 0, %0, c1, c0, 0":"=r" (i));

	/* set i-cache */
	i |= 0x1000;

	/* write back to control register */
	asm ("mcr p15, 0, %0, c1, c0, 0": :"r" (i));
}

void icache_disable (void)
{
	register u32 i;

	/* read control register */
	asm ("mrc p15, 0, %0, c1, c0, 0":"=r" (i));

	/* clear i-cache */
	i &= ~0x1000;

	/* write back to control register */
	asm ("mcr p15, 0, %0, c1, c0, 0": :"r" (i));

	/* flush i-cache */
	asm ("mcr p15, 0, %0, c7, c5, 0": :"r" (i));
}

int icache_status (void)
{
	register u32 i;

	/* read control register */
	asm ("mrc p15, 0, %0, c1, c0, 0":"=r" (i));

	/* return bit */
	return (i & 0x1000);
}

/* we will never enable dcache, because we have to setup MMU first */
void dcache_enable (void)
{
	return;
}

void dcache_disable (void)
{
	return;
}

int dcache_status (void)
{
	return 0;					/* always off */
}