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
|
/* SPDX-License-Identifier: GPL-2.0-only */
#if ENV_X86
#include <cpu/x86/pae.h>
#else
#define memset_pae(a, b, c, d, e) 0
#define PAE_PGTL_ALIGN 0
#define PAE_PGTL_SIZE 0
#define PAE_VMEM_ALIGN 0
#define PAE_VMEM_SIZE 0
#endif
#include <memrange.h>
#include <bootmem.h>
#include <bootstate.h>
#include <symbols.h>
#include <console/console.h>
#include <arch/memory_clear.h>
#include <string.h>
#include <security/memory/memory.h>
#include <cbmem.h>
#include <acpi/acpi.h>
#include <drivers/efi/capsules.h>
/* Helper to find free space for memset_pae. */
static uintptr_t get_free_memory_range(struct memranges *mem,
const resource_t align,
const resource_t size)
{
const struct range_entry *r;
/* Find a spot for virtual memory address */
memranges_each_entry(r, mem) {
if (range_entry_tag(r) != BM_MEM_RAM)
continue;
if (ALIGN_UP(range_entry_base(r) + size, align) + size >
range_entry_end(r))
continue;
return ALIGN_UP(range_entry_base(r) + size, align);
}
printk(BIOS_ERR, "%s: Couldn't find free memory range\n", __func__);
return 0;
}
/*
* Clears all memory regions marked as BM_MEM_RAM.
* Uses memset_pae if the memory region can't be accessed by memset and
* architecture is x86.
*
* @return 0 on success, 1 on error
*/
static void clear_memory(void *unused)
{
const struct range_entry *r;
struct memranges mem;
uintptr_t pgtbl, vmem_addr;
if (acpi_is_wakeup_s3())
return;
/* Process capsules before clearing memory and only if not waking up from S3. */
efi_parse_capsules();
if (!security_clear_dram_request())
return;
/* FSP1.0 is marked as MMIO and won't appear here */
memranges_init(&mem, IORESOURCE_MEM | IORESOURCE_FIXED |
IORESOURCE_STORED | IORESOURCE_ASSIGNED |
IORESOURCE_CACHEABLE,
IORESOURCE_MEM | IORESOURCE_FIXED |
IORESOURCE_STORED | IORESOURCE_ASSIGNED |
IORESOURCE_CACHEABLE,
BM_MEM_RAM);
/* Add reserved entries */
void *baseptr;
size_t size;
/* Only skip CBMEM, stage program, stack and heap are included there. */
if (cbmem_get_region(&baseptr, &size))
die("Could not find cbmem region");
memranges_insert(&mem, (uintptr_t)baseptr, size, BM_MEM_TABLE);
if (ENV_X86) {
/* Find space for PAE enabled memset */
pgtbl = get_free_memory_range(&mem, PAE_PGTL_ALIGN, PAE_PGTL_SIZE);
/* Don't touch page tables while clearing */
memranges_insert(&mem, pgtbl, PAE_PGTL_SIZE, BM_MEM_TABLE);
vmem_addr = get_free_memory_range(&mem, PAE_VMEM_ALIGN, PAE_VMEM_SIZE);
printk(BIOS_SPEW, "%s: pgtbl at %p, virt memory at %p\n",
__func__, (void *)pgtbl, (void *)vmem_addr);
}
/* Now clear all usable DRAM */
memranges_each_entry(r, &mem) {
if (range_entry_tag(r) != BM_MEM_RAM)
continue;
printk(BIOS_DEBUG, "%s: Clearing DRAM %016llx-%016llx\n",
__func__, range_entry_base(r), range_entry_end(r));
/* Does regular memset work? */
if (sizeof(resource_t) == sizeof(void *) ||
!(range_entry_end(r) >> (sizeof(void *) * 8))) {
/* fastpath */
memset((void *)(uintptr_t)range_entry_base(r), 0,
range_entry_size(r));
}
/* Use PAE if available */
else if (ENV_X86) {
if (memset_pae(range_entry_base(r), 0,
range_entry_size(r), (void *)pgtbl,
(void *)vmem_addr))
printk(BIOS_ERR, "%s: Failed to memset "
"memory\n", __func__);
} else {
printk(BIOS_ERR, "%s: Failed to memset memory\n",
__func__);
}
}
if (ENV_X86) {
/* Clear previously skipped memory reserved for pagetables */
printk(BIOS_DEBUG, "%s: Clearing DRAM %016lx-%016lx\n",
__func__, pgtbl, pgtbl + PAE_PGTL_SIZE);
memset((void *)pgtbl, 0, PAE_PGTL_SIZE);
}
memranges_teardown(&mem);
}
/* After DEV_INIT as MTRRs needs to be configured on x86 */
BOOT_STATE_INIT_ENTRY(BS_DEV_INIT, BS_ON_EXIT, clear_memory, NULL);
|
