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
|
/*
* This file is part of the coreboot project.
*
* Copyright (C) 2005 Yinghai Lu
*
* 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 <console/console.h>
#include <cpu/cpu.h>
#include <cpu/x86/pae.h>
#include <string.h>
static void paging_off(void)
{
__asm__ __volatile__ (
/* Disable paging */
"movl %%cr0, %%eax\n\t"
"andl $0x7FFFFFFF, %%eax\n\t"
"movl %%eax, %%cr0\n\t"
/* Disable pae */
"movl %%cr4, %%eax\n\t"
"andl $0xFFFFFFDF, %%eax\n\t"
"movl %%eax, %%cr4\n\t"
:
:
: "eax"
);
}
static void paging_on(void *pdp)
{
__asm__ __volatile__(
/* Load the page table address */
"movl %0, %%cr3\n\t"
/* Enable pae */
"movl %%cr4, %%eax\n\t"
"orl $0x00000020, %%eax\n\t"
"movl %%eax, %%cr4\n\t"
/* Enable paging */
"movl %%cr0, %%eax\n\t"
"orl $0x80000000, %%eax\n\t"
"movl %%eax, %%cr0\n\t"
:
: "r" (pdp)
: "eax"
);
}
void *map_2M_page(unsigned long page)
{
struct pde {
uint32_t addr_lo;
uint32_t addr_hi;
} __attribute__ ((packed));
struct pg_table {
struct pde pd[2048];
struct pde pdp[512];
} __attribute__ ((packed));
static struct pg_table pgtbl[CONFIG_MAX_CPUS] __attribute__ ((aligned(4096)));
static unsigned long mapped_window[CONFIG_MAX_CPUS];
unsigned long index;
unsigned long window;
void *result;
int i;
index = cpu_index();
if (index >= CONFIG_MAX_CPUS) {
return MAPPING_ERROR;
}
window = page >> 10;
if (window != mapped_window[index]) {
paging_off();
if (window > 1) {
struct pde *pd, *pdp;
/* Point the page directory pointers at the page directories */
memset(&pgtbl[index].pdp, 0, sizeof(pgtbl[index].pdp));
pd = pgtbl[index].pd;
pdp = pgtbl[index].pdp;
pdp[0].addr_lo = ((uint32_t)&pd[512*0])|1;
pdp[1].addr_lo = ((uint32_t)&pd[512*1])|1;
pdp[2].addr_lo = ((uint32_t)&pd[512*2])|1;
pdp[3].addr_lo = ((uint32_t)&pd[512*3])|1;
/* The first half of the page table is identity mapped */
for (i = 0; i < 1024; i++) {
pd[i].addr_lo = ((i & 0x3ff) << 21) | 0xE3;
pd[i].addr_hi = 0;
}
/* The second half of the page table holds the mapped page */
for (i = 1024; i < 2048; i++) {
pd[i].addr_lo = ((window & 1) << 31) | ((i & 0x3ff) << 21) | 0xE3;
pd[i].addr_hi = (window >> 1);
}
paging_on(pdp);
}
mapped_window[index] = window;
}
if (window == 0) {
result = (void *)(page << 21);
} else {
result = (void *)(0x80000000 | ((page & 0x3ff) << 21));
}
return result;
}
|