summaryrefslogtreecommitdiffstats
path: root/arch/mips/kernel/relocate_kernel.S
blob: 43d2d78d3287dfbfa52ad7fb1a52f6571d9deaa3 (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
183
184
185
186
/*
 * relocate_kernel.S for kexec
 * Created by <nschichan@corp.free.fr> on Thu Oct 12 17:49:57 2006
 *
 * This source code is licensed under the GNU General Public License,
 * Version 2.  See the file COPYING for more details.
 */

#include <asm/asm.h>
#include <asm/asmmacro.h>
#include <asm/regdef.h>
#include <asm/mipsregs.h>
#include <asm/stackframe.h>
#include <asm/addrspace.h>

LEAF(relocate_new_kernel)
	PTR_L a0,	arg0
	PTR_L a1,	arg1
	PTR_L a2,	arg2
	PTR_L a3,	arg3

	PTR_L		s0, kexec_indirection_page
	PTR_L		s1, kexec_start_address

process_entry:
	PTR_L		s2, (s0)
	PTR_ADD		s0, s0, SZREG

	/* destination page */
	and		s3, s2, 0x1
	beq		s3, zero, 1f
	and		s4, s2, ~0x1	/* store destination addr in s4 */
	b		process_entry

1:
	/* indirection page, update s0	*/
	and		s3, s2, 0x2
	beq		s3, zero, 1f
	and		s0, s2, ~0x2
	b		process_entry

1:
	/* done page */
	and		s3, s2, 0x4
	beq		s3, zero, 1f
	b		done
1:
	/* source page */
	and		s3, s2, 0x8
	beq		s3, zero, process_entry
	and		s2, s2, ~0x8
	li		s6, (1 << _PAGE_SHIFT) / SZREG

copy_word:
	/* copy page word by word */
	REG_L		s5, (s2)
	REG_S		s5, (s4)
	PTR_ADD		s4, s4, SZREG
	PTR_ADD		s2, s2, SZREG
	LONG_SUB	s6, s6, 1
	beq		s6, zero, process_entry
	b		copy_word
	b		process_entry

done:
#ifdef CONFIG_SMP
	/* kexec_flag reset is signal to other CPUs what kernel
	   was moved to it's location. Note - we need relocated address
	   of kexec_flag.  */

	bal		1f
 1:	move		t1,ra;
	PTR_LA		t2,1b
	PTR_LA		t0,kexec_flag
	PTR_SUB		t0,t0,t2;
	PTR_ADD		t0,t1,t0;
	LONG_S		zero,(t0)
#endif

#ifdef CONFIG_CPU_CAVIUM_OCTEON
	/* We need to flush I-cache before jumping to new kernel.
	 * Unfortunatelly, this code is cpu-specific.
	 */
	.set push
	.set noreorder
	syncw
	syncw
	synci		0($0)
	.set pop
#else
	sync
#endif
	/* jump to kexec_start_address */
	j		s1
	END(relocate_new_kernel)

#ifdef CONFIG_SMP
/*
 * Other CPUs should wait until code is relocated and
 * then start at entry (?) point.
 */
LEAF(kexec_smp_wait)
	PTR_L		a0, s_arg0
	PTR_L		a1, s_arg1
	PTR_L		a2, s_arg2
	PTR_L		a3, s_arg3
	PTR_L		s1, kexec_start_address

	/* Non-relocated address works for args and kexec_start_address ( old
	 * kernel is not overwritten). But we need relocated address of
	 * kexec_flag.
	 */

	bal		1f
1:	move		t1,ra;
	PTR_LA		t2,1b
	PTR_LA		t0,kexec_flag
	PTR_SUB		t0,t0,t2;
	PTR_ADD		t0,t1,t0;

1:	LONG_L		s0, (t0)
	bne		s0, zero,1b

#ifdef CONFIG_CPU_CAVIUM_OCTEON
	.set push
	.set noreorder
	synci		0($0)
	.set pop
#else
	sync
#endif
	j		s1
	END(kexec_smp_wait)
#endif

#ifdef __mips64
       /* all PTR's must be aligned to 8 byte in 64-bit mode */
       .align  3
#endif

/* All parameters to new kernel are passed in registers a0-a3.
 * kexec_args[0..3] are uses to prepare register values.
 */

kexec_args:
	EXPORT(kexec_args)
arg0:	PTR		0x0
arg1:	PTR		0x0
arg2:	PTR		0x0
arg3:	PTR		0x0
	.size	kexec_args,PTRSIZE*4

#ifdef CONFIG_SMP
/*
 * Secondary CPUs may have different kernel parameters in
 * their registers a0-a3. secondary_kexec_args[0..3] are used
 * to prepare register values.
 */
secondary_kexec_args:
	EXPORT(secondary_kexec_args)
s_arg0: PTR		0x0
s_arg1: PTR		0x0
s_arg2: PTR		0x0
s_arg3: PTR		0x0
	.size	secondary_kexec_args,PTRSIZE*4
kexec_flag:
	LONG		0x1

#endif

kexec_start_address:
	EXPORT(kexec_start_address)
	PTR		0x0
	.size		kexec_start_address, PTRSIZE

kexec_indirection_page:
	EXPORT(kexec_indirection_page)
	PTR		0
	.size		kexec_indirection_page, PTRSIZE

relocate_new_kernel_end:

relocate_new_kernel_size:
	EXPORT(relocate_new_kernel_size)
	PTR		relocate_new_kernel_end - relocate_new_kernel
	.size		relocate_new_kernel_size, PTRSIZE