summaryrefslogtreecommitdiff
path: root/post/lib_powerpc/b.c
blob: 43b4c353078cc1541885abdf136ccd3addef9f16 (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
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
/*
 * (C) Copyright 2002
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>

/*
 * CPU test
 * Branch instructions:		b, bl, bc
 *
 * The first 2 instructions (b, bl) are verified by jumping
 * to a fixed address and checking whether control was transfered
 * to that very point. For the bl instruction the value of the
 * link register is checked as well (using mfspr).
 * To verify the bc instruction various combinations of the BI/BO
 * fields, the CTR and the condition register values are
 * checked. The list of such combinations is pre-built and
 * linked in U-Boot at build time.
 */

#include <post.h>
#include "cpu_asm.h"

#if CONFIG_POST & CONFIG_SYS_POST_CPU

extern void cpu_post_exec_11 (ulong *code, ulong *res, ulong op1);
extern void cpu_post_exec_31 (ulong *code, ulong *ctr, ulong *lr, ulong *jump,
    ulong cr);

static int cpu_post_test_bc (ulong cmd, ulong bo, ulong bi,
    int pjump, int decr, int link, ulong pctr, ulong cr)
{
    int ret = 0;
    ulong lr = 0;
    ulong ctr = pctr;
    ulong jump;

    unsigned long code[] =
    {
	ASM_MTCR(6),
	ASM_MFLR(6),
	ASM_MTCTR(3),
	ASM_MTLR(4),
	ASM_LI(5, 1),
	ASM_3O(cmd, bo, bi, 8),
	ASM_LI(5, 0),
	ASM_MFCTR(3),
	ASM_MFLR(4),
	ASM_MTLR(6),
	ASM_BLR,
    };

    cpu_post_exec_31 (code, &ctr, &lr, &jump, cr);

    if (ret == 0)
	ret = pjump == jump ? 0 : -1;
    if (ret == 0)
    {
	if (decr)
	    ret = pctr == ctr + 1 ? 0 : -1;
	else
	    ret = pctr == ctr ? 0 : -1;
    }
    if (ret == 0)
    {
	if (link)
	    ret = lr == (ulong) code + 24 ? 0 : -1;
	else
	    ret = lr == 0 ? 0 : -1;
    }

    return ret;
}

int cpu_post_test_b (void)
{
    int ret = 0;
    unsigned int i;
    int flag = disable_interrupts();

    if (ret == 0)
    {
	ulong code[] =
	{
	   ASM_MFLR(4),
	   ASM_MTLR(3),
	   ASM_B(4),
	   ASM_MFLR(3),
	   ASM_MTLR(4),
	   ASM_BLR,
	};
	ulong res;

	cpu_post_exec_11 (code, &res, 0);

	ret = res == 0 ? 0 : -1;

	if (ret != 0)
	{
	    post_log ("Error at b1 test !\n");
	}
    }

    if (ret == 0)
    {
	ulong code[] =
	{
	   ASM_MFLR(4),
	   ASM_MTLR(3),
	   ASM_BL(4),
	   ASM_MFLR(3),
	   ASM_MTLR(4),
	   ASM_BLR,
	};
	ulong res;

	cpu_post_exec_11 (code, &res, 0);

	ret = res == (ulong)code + 12 ? 0 : -1;

	if (ret != 0)
	{
	    post_log ("Error at b2 test !\n");
	}
    }

    if (ret == 0)
    {
	ulong cc, cd;
	int cond;
	ulong ctr;
	int link;

	i = 0;

	for (cc = 0; cc < 4 && ret == 0; cc++)
	{
	    for (cd = 0; cd < 4 && ret == 0; cd++)
	    {
		for (link = 0; link <= 1 && ret == 0; link++)
		{
		    for (cond = 0; cond <= 1 && ret == 0; cond++)
		    {
			for (ctr = 1; ctr <= 2 && ret == 0; ctr++)
			{
			    int decr = cd < 2;
			    int cr = cond ? 0x80000000 : 0x00000000;
			    int jumpc = cc >= 2 ||
					(cc == 0 && !cond) ||
					(cc == 1 && cond);
			    int jumpd = cd >= 2 ||
					(cd == 0 && ctr != 1) ||
					(cd == 1 && ctr == 1);
			    int jump = jumpc && jumpd;

			    ret = cpu_post_test_bc (link ? OP_BCL : OP_BC,
				(cc << 3) + (cd << 1), 0, jump, decr, link,
				ctr, cr);

			    if (ret != 0)
			    {
				post_log ("Error at b3 test %d !\n", i);
			    }

			    i++;
			}
		    }
		}
	    }
	}
    }

    if (flag)
	enable_interrupts();

    return ret;
}

#endif