aboutsummaryrefslogtreecommitdiff
path: root/cpu/mpc5xx/cpu.c
blob: cc695118e043a4c4aff42d0657940037e37928fc (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
153
154
/*
 * (C) Copyright 2003
 * Martin Winistoerfer, martinwinistoerfer@gmx.ch.
 *
 * 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,
 */

/*
 * File:		cpu.c
 *
 * Discription:		Some cpu specific function for watchdog,
 *                      cpu version test, clock setting ...
 *
 */


#include <common.h>
#include <watchdog.h>
#include <command.h>
#include <mpc5xx.h>


#if (defined(CONFIG_MPC555))
#  define	ID_STR	"MPC555/556"

/*
 * Check version of cpu with Processor Version Register (PVR)
 */
static int check_cpu_version (long clock, uint pvr, uint immr)
{
    char buf[32];
	/* The highest 16 bits should be 0x0002 for a MPC555/556 */
	if ((pvr >> 16) == 0x0002) {
		printf (" " ID_STR " Version %x", (pvr >> 16));
		printf (" at %s MHz:", strmhz (buf, clock));
	} else {
		printf ("Not supported cpu version");
		return -1;
	}
	return 0;
}
#endif /* CONFIG_MPC555 */


/*
 * Check version of mpc5xx
 */
int checkcpu (void)
{
	DECLARE_GLOBAL_DATA_PTR;

	ulong clock = gd->cpu_clk;
	uint immr = get_immr (0);	/* Return full IMMR contents */
	uint pvr = get_pvr ();		/* Retrieve PVR register */

	puts ("CPU:   ");

	return check_cpu_version (clock, pvr, immr);
}

/*
 * Called by macro WATCHDOG_RESET
 */
#if defined(CONFIG_WATCHDOG)
void watchdog_reset (void)
{
	int re_enable = disable_interrupts ();

	reset_5xx_watchdog ((immap_t *) CFG_IMMR);
	if (re_enable)
		enable_interrupts ();
}

/*
 * Will clear software reset
 */
void reset_5xx_watchdog (volatile immap_t * immr)
{
	/* Use the MPC5xx Internal Watchdog */
	immr->im_siu_conf.sc_swsr = 0x556c;	/* Prevent SW time-out */
	immr->im_siu_conf.sc_swsr = 0xaa39;
}

#endif /* CONFIG_WATCHDOG */


/*
 * Get timebase clock frequency
 */
unsigned long get_tbclk (void)
{
	DECLARE_GLOBAL_DATA_PTR;
	volatile immap_t *immr = (volatile immap_t *) CFG_IMMR;
	ulong oscclk, factor;

	if (immr->im_clkrst.car_sccr & SCCR_TBS) {
		return (gd->cpu_clk / 16);
	}

	factor = (((CFG_PLPRCR) & PLPRCR_MF_MSK) >> PLPRCR_MF_SHIFT) + 1;

	oscclk = gd->cpu_clk / factor;

	if ((immr->im_clkrst.car_sccr & SCCR_RTSEL) == 0 || factor > 2) {
		return (oscclk / 4);
	}
	return (oscclk / 16);
}


/*
 * Reset board
 */
int do_reset (cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
{
	ulong addr;

	/* Interrupts off, enable reset */
	__asm__ volatile	("  mtspr	81, %r0		\n\t"
				 "  mfmsr	%r3		\n\t"
				 "  rlwinm	%r31,%r3,0,25,23\n\t"
				 "  mtmsr	%r31		\n\t");
	/*
	 * Trying to execute the next instruction at a non-existing address
	 * should cause a machine check, resulting in reset
	 */
#ifdef CFG_RESET_ADDRESS
	addr = CFG_RESET_ADDRESS;
#else
	/*
	 * note: when CFG_MONITOR_BASE points to a RAM address, CFG_MONITOR_BASE         * - sizeof (ulong) is usually a valid address. Better pick an address
	 * known to be invalid on your system and assign it to CFG_RESET_ADDRESS.
	 * "(ulong)-1" used to be a good choice for many systems...
	 */
	addr = CFG_MONITOR_BASE - sizeof (ulong);
#endif
	((void (*) (void)) addr) ();
	return 1;
}