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
198
199
200
201
202
203
204
205
206
207
208
|
/*
* This file is part of the coreboot project.
*
* Copyright (C) 2000,2007 Ronald G. Minnich <rminnich@gmail.com>
* Copyright (C) 2007-2008 coresystems GmbH
* Copyright (C) 2012 Kyösti Mälkki <kyosti.malkki@gmail.com>
*
* 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; version 2 of the License.
*
* 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.
*/
#include <cpu/x86/mtrr.h>
#include <cpu/x86/cache.h>
#include <cpu/x86/post_code.h>
#define CACHE_AS_RAM_SIZE CONFIG_DCACHE_RAM_SIZE
#define CACHE_AS_RAM_BASE CONFIG_DCACHE_RAM_BASE
.code32
_cache_as_ram_setup:
/* Save the BIST result. */
movl %eax, %ebp
cache_as_ram:
post_code(0x20)
/* Send INIT IPI to all excluding ourself. */
movl $0x000C4500, %eax
movl $0xFEE00300, %esi
movl %eax, (%esi)
/* All CPUs need to be in Wait for SIPI state */
wait_for_sipi:
movl (%esi), %eax
bt $12, %eax
jc wait_for_sipi
post_code(0x22)
/* Clear/disable fixed MTRRs */
mov $fixed_mtrr_list_size, %ebx
xor %eax, %eax
xor %edx, %edx
clear_fixed_mtrr:
add $-2, %ebx
movzwl fixed_mtrr_list(%ebx), %ecx
wrmsr
jnz clear_fixed_mtrr
/* Figure put how many MTRRs we have, and clear them out */
mov $MTRR_CAP_MSR, %ecx
rdmsr
movzb %al, %ebx /* Number of variable MTRRs */
mov $MTRR_PHYS_BASE(0), %ecx
xor %eax, %eax
xor %edx, %edx
clear_var_mtrr:
wrmsr
inc %ecx
wrmsr
inc %ecx
dec %ebx
jnz clear_var_mtrr
post_code(0x22)
/* Configure the default memory type to uncacheable. */
movl $MTRR_DEF_TYPE_MSR, %ecx
rdmsr
andl $(~0x00000cff), %eax
wrmsr
/* Determine CPU_ADDR_BITS and load PHYSMASK high word to %edx. */
movl $0x80000008, %eax
cpuid
movb %al, %cl
sub $32, %cl
movl $1, %edx
shl %cl, %edx
subl $1, %edx
/* Preload high word of address mask (in %edx) for Variable
MTRRs 0 and 1. */
addrsize_set_high:
xorl %eax, %eax
movl $MTRR_PHYS_MASK(0), %ecx
wrmsr
movl $MTRR_PHYS_MASK(1), %ecx
wrmsr
post_code(0x23)
/* Set Cache-as-RAM base address. */
movl $(MTRR_PHYS_BASE(0)), %ecx
movl $(CACHE_AS_RAM_BASE | MTRR_TYPE_WRBACK), %eax
xorl %edx, %edx
wrmsr
post_code(0x24)
/* Set Cache-as-RAM mask. */
movl $(MTRR_PHYS_MASK(0)), %ecx
rdmsr
movl $(~(CACHE_AS_RAM_SIZE - 1) | MTRR_PHYS_MASK_VALID), %eax
wrmsr
post_code(0x25)
/* Enable MTRR. */
movl $MTRR_DEF_TYPE_MSR, %ecx
rdmsr
orl $MTRR_DEF_TYPE_EN, %eax
wrmsr
/* Enable L2 cache. */
movl $0x11e, %ecx
rdmsr
orl $(1 << 8), %eax
wrmsr
/* Enable cache (CR0.CD = 0, CR0.NW = 0). */
movl %cr0, %eax
andl $(~(CR0_CacheDisable | CR0_NoWriteThrough)), %eax
invd
movl %eax, %cr0
/* Clear the cache memory region. This will also fill up the cache. */
movl $CACHE_AS_RAM_BASE, %esi
movl %esi, %edi
movl $(CACHE_AS_RAM_SIZE >> 2), %ecx
xorl %eax, %eax
rep stosl
post_code(0x26)
/* Enable Cache-as-RAM mode by disabling cache. */
movl %cr0, %eax
orl $CR0_CacheDisable, %eax
movl %eax, %cr0
/* Enable cache for our code in Flash because we do XIP here */
movl $MTRR_PHYS_BASE(1), %ecx
xorl %edx, %edx
/*
* IMPORTANT: The following calculation _must_ be done at runtime. See
* https://www.coreboot.org/pipermail/coreboot/2010-October/060855.html
*/
movl $_program, %eax
andl $(~(CONFIG_XIP_ROM_SIZE - 1)), %eax
orl $MTRR_TYPE_WRPROT, %eax
wrmsr
movl $MTRR_PHYS_MASK(1), %ecx
rdmsr
movl $(~(CONFIG_XIP_ROM_SIZE - 1) | MTRR_PHYS_MASK_VALID), %eax
wrmsr
post_code(0x28)
/* Enable cache. */
movl %cr0, %eax
andl $(~(CR0_CacheDisable | CR0_NoWriteThrough)), %eax
movl %eax, %cr0
/* Setup the stack. */
movl $(CONFIG_DCACHE_RAM_BASE + CONFIG_DCACHE_RAM_SIZE), %eax
movl %eax, %esp
/* Align the stack 16 bytes */
andl $0xfffffff0, %esp
/* Account for pushing the BIST result */
subl $12, %esp
/* Restore the BIST result. */
movl %ebp, %eax
movl %esp, %ebp
pushl %eax
before_romstage:
post_code(0x29)
/* Call romstage.c main function. */
call romstage_main
/* Should never see this postcode */
post_code(POST_DEAD_CODE)
.Lhlt:
hlt
jmp .Lhlt
fixed_mtrr_list:
.word MTRR_FIX_64K_00000
.word MTRR_FIX_16K_80000
.word MTRR_FIX_16K_A0000
.word MTRR_FIX_4K_C0000
.word MTRR_FIX_4K_C8000
.word MTRR_FIX_4K_D0000
.word MTRR_FIX_4K_D8000
.word MTRR_FIX_4K_E0000
.word MTRR_FIX_4K_E8000
.word MTRR_FIX_4K_F0000
.word MTRR_FIX_4K_F8000
fixed_mtrr_list_size = . - fixed_mtrr_list
_cache_as_ram_setup_end:
|