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
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
|
/*
* (C) Copyright 2008-2011
* Graeme Russ, <graeme.russ@gmail.com>
*
* (C) Copyright 2002
* Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
*
* (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
*/
#include <common.h>
#include <command.h>
#include <asm/processor.h>
#include <asm/processor-flags.h>
#include <asm/interrupt.h>
#include <linux/compiler.h>
/*
* Constructor for a conventional segment GDT (or LDT) entry
* This is a macro so it can be used in initialisers
*/
#define GDT_ENTRY(flags, base, limit) \
((((base) & 0xff000000ULL) << (56-24)) | \
(((flags) & 0x0000f0ffULL) << 40) | \
(((limit) & 0x000f0000ULL) << (48-16)) | \
(((base) & 0x00ffffffULL) << 16) | \
(((limit) & 0x0000ffffULL)))
struct gdt_ptr {
u16 len;
u32 ptr;
} __packed;
static void load_ds(u32 segment)
{
asm volatile("movl %0, %%ds" : : "r" (segment * X86_GDT_ENTRY_SIZE));
}
static void load_es(u32 segment)
{
asm volatile("movl %0, %%es" : : "r" (segment * X86_GDT_ENTRY_SIZE));
}
static void load_fs(u32 segment)
{
asm volatile("movl %0, %%fs" : : "r" (segment * X86_GDT_ENTRY_SIZE));
}
static void load_gs(u32 segment)
{
asm volatile("movl %0, %%gs" : : "r" (segment * X86_GDT_ENTRY_SIZE));
}
static void load_ss(u32 segment)
{
asm volatile("movl %0, %%ss" : : "r" (segment * X86_GDT_ENTRY_SIZE));
}
static void load_gdt(const u64 *boot_gdt, u16 num_entries)
{
struct gdt_ptr gdt;
gdt.len = (num_entries * 8) - 1;
gdt.ptr = (u32)boot_gdt;
asm volatile("lgdtl %0\n" : : "m" (gdt));
}
void setup_gdt(gd_t *id, u64 *gdt_addr)
{
/* CS: code, read/execute, 4 GB, base 0 */
gdt_addr[X86_GDT_ENTRY_32BIT_CS] = GDT_ENTRY(0xc09b, 0, 0xfffff);
/* DS: data, read/write, 4 GB, base 0 */
gdt_addr[X86_GDT_ENTRY_32BIT_DS] = GDT_ENTRY(0xc093, 0, 0xfffff);
/* FS: data, read/write, 4 GB, base (Global Data Pointer) */
gdt_addr[X86_GDT_ENTRY_32BIT_FS] = GDT_ENTRY(0xc093, (ulong)id, 0xfffff);
/* 16-bit CS: code, read/execute, 64 kB, base 0 */
gdt_addr[X86_GDT_ENTRY_16BIT_CS] = GDT_ENTRY(0x109b, 0, 0x0ffff);
/* 16-bit DS: data, read/write, 64 kB, base 0 */
gdt_addr[X86_GDT_ENTRY_16BIT_DS] = GDT_ENTRY(0x1093, 0, 0x0ffff);
load_gdt(gdt_addr, X86_GDT_NUM_ENTRIES);
load_ds(X86_GDT_ENTRY_32BIT_DS);
load_es(X86_GDT_ENTRY_32BIT_DS);
load_gs(X86_GDT_ENTRY_32BIT_DS);
load_ss(X86_GDT_ENTRY_32BIT_DS);
load_fs(X86_GDT_ENTRY_32BIT_FS);
}
int x86_cpu_init_f(void)
{
const u32 em_rst = ~X86_CR0_EM;
const u32 mp_ne_set = X86_CR0_MP | X86_CR0_NE;
/* initialize FPU, reset EM, set MP and NE */
asm ("fninit\n" \
"movl %%cr0, %%eax\n" \
"andl %0, %%eax\n" \
"orl %1, %%eax\n" \
"movl %%eax, %%cr0\n" \
: : "i" (em_rst), "i" (mp_ne_set) : "eax");
return 0;
}
int cpu_init_f(void) __attribute__((weak, alias("x86_cpu_init_f")));
int x86_cpu_init_r(void)
{
/* Initialize core interrupt and exception functionality of CPU */
cpu_init_interrupts();
return 0;
}
int cpu_init_r(void) __attribute__((weak, alias("x86_cpu_init_r")));
void x86_enable_caches(void)
{
const u32 nw_cd_rst = ~(X86_CR0_NW | X86_CR0_CD);
/* turn on the cache and disable write through */
asm("movl %%cr0, %%eax\n"
"andl %0, %%eax\n"
"movl %%eax, %%cr0\n"
"wbinvd\n" : : "i" (nw_cd_rst) : "eax");
}
void enable_caches(void) __attribute__((weak, alias("x86_enable_caches")));
int x86_init_cache(void)
{
enable_caches();
return 0;
}
int init_cache(void) __attribute__((weak, alias("x86_init_cache")));
int do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
printf("resetting ...\n");
/* wait 50 ms */
udelay(50000);
disable_interrupts();
reset_cpu(0);
/*NOTREACHED*/
return 0;
}
void flush_cache(unsigned long dummy1, unsigned long dummy2)
{
asm("wbinvd\n");
}
void __attribute__ ((regparm(0))) generate_gpf(void);
/* segment 0x70 is an arbitrary segment which does not exist */
asm(".globl generate_gpf\n"
".hidden generate_gpf\n"
".type generate_gpf, @function\n"
"generate_gpf:\n"
"ljmp $0x70, $0x47114711\n");
void __reset_cpu(ulong addr)
{
printf("Resetting using x86 Triple Fault\n");
set_vector(13, generate_gpf); /* general protection fault handler */
set_vector(8, generate_gpf); /* double fault handler */
generate_gpf(); /* start the show */
}
void reset_cpu(ulong addr) __attribute__((weak, alias("__reset_cpu")));
|
