1 /*
2 * Copyright (c) 2019 Intel Corporation
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #include <zephyr/kernel.h>
8 #include <string.h>
9 #include <zephyr/arch/x86/multiboot.h>
10 #include <zephyr/arch/x86/memmap.h>
11
12 struct multiboot_info multiboot_info;
13
14 #ifdef CONFIG_DYNAMIC_BOOTARGS
15 __pinned_noinit char multiboot_cmdline[CONFIG_BOOTARGS_ARGS_BUFFER_SIZE];
16
get_bootargs(void)17 const char *get_bootargs(void)
18 {
19 return multiboot_cmdline;
20 }
21 #endif /* CONFIG_DYNAMIC_BOOTARGS */
22
23 /*
24 * called very early in the boot process to fetch data out of the multiboot
25 * info struct. we need to grab the relevant data before any dynamic memory
26 * allocation takes place, lest the struct itself or any data it points to
27 * be overwritten before we read it.
28 */
29
clear_memmap(int index)30 static inline void clear_memmap(int index)
31 {
32 while (index < CONFIG_X86_MEMMAP_ENTRIES) {
33 x86_memmap[index].type = X86_MEMMAP_ENTRY_UNUSED;
34 ++index;
35 }
36 }
37
z_multiboot_init(struct multiboot_info * info_pa)38 void z_multiboot_init(struct multiboot_info *info_pa)
39 {
40 struct multiboot_info *info;
41
42 #if defined(CONFIG_ARCH_MAPS_ALL_RAM) || !defined(CONFIG_X86_MMU)
43 /*
44 * Since the struct from bootloader resides in memory
45 * and all memory is mapped, there is no need to
46 * manually map it before accessing.
47 *
48 * Without MMU, all memory are identity-mapped already
49 * so there is no need to map them again.
50 */
51 info = info_pa;
52 #else
53 k_mem_map_phys_bare((uint8_t **)&info, POINTER_TO_UINT(info_pa),
54 sizeof(*info_pa), K_MEM_CACHE_NONE);
55 #endif /* CONFIG_ARCH_MAPS_ALL_RAM */
56
57 if (info == NULL) {
58 return;
59 }
60
61 memcpy(&multiboot_info, info, sizeof(*info));
62
63 #ifdef CONFIG_MULTIBOOT_MEMMAP
64 /*
65 * If the extended map (basically, the equivalent of
66 * the BIOS E820 map) is available, then use that.
67 */
68
69 if ((info->flags & MULTIBOOT_INFO_FLAGS_MMAP) &&
70 (x86_memmap_source < X86_MEMMAP_SOURCE_MULTIBOOT_MMAP)) {
71 uintptr_t address;
72 uintptr_t address_end;
73 struct multiboot_mmap *mmap;
74 int index = 0;
75 uint32_t type;
76
77 #if defined(CONFIG_ARCH_MAPS_ALL_RAM) || !defined(CONFIG_X86_MMU)
78 address = info->mmap_addr;
79 #else
80 uint8_t *address_va;
81
82 k_mem_map_phys_bare(&address_va, info->mmap_addr, info->mmap_length,
83 K_MEM_CACHE_NONE);
84
85 address = POINTER_TO_UINT(address_va);
86 #endif /* CONFIG_ARCH_MAPS_ALL_RAM */
87
88 address_end = address + info->mmap_length;
89
90 while ((address < address_end) &&
91 (index < CONFIG_X86_MEMMAP_ENTRIES)) {
92 mmap = UINT_TO_POINTER(address);
93
94 x86_memmap[index].base = mmap->base;
95 x86_memmap[index].length = mmap->length;
96
97 switch (mmap->type) {
98 case MULTIBOOT_MMAP_RAM:
99 type = X86_MEMMAP_ENTRY_RAM;
100 break;
101 case MULTIBOOT_MMAP_ACPI:
102 type = X86_MEMMAP_ENTRY_ACPI;
103 break;
104 case MULTIBOOT_MMAP_NVS:
105 type = X86_MEMMAP_ENTRY_NVS;
106 break;
107 case MULTIBOOT_MMAP_DEFECTIVE:
108 type = X86_MEMMAP_ENTRY_DEFECTIVE;
109 break;
110 default:
111 type = X86_MEMMAP_ENTRY_UNKNOWN;
112 }
113
114 x86_memmap[index].type = type;
115 ++index;
116 address += mmap->size + sizeof(mmap->size);
117 }
118
119 x86_memmap_source = X86_MEMMAP_SOURCE_MULTIBOOT_MMAP;
120 clear_memmap(index);
121 }
122
123 /* If no extended map is available, fall back to the basic map. */
124
125 if ((info->flags & MULTIBOOT_INFO_FLAGS_MEM) &&
126 (x86_memmap_source < X86_MEMMAP_SOURCE_MULTIBOOT_MEM)) {
127 x86_memmap[0].base = 0;
128 x86_memmap[0].length = info->mem_lower * 1024ULL;
129 x86_memmap[0].type = X86_MEMMAP_ENTRY_RAM;
130
131 if (CONFIG_X86_MEMMAP_ENTRIES > 1) {
132 x86_memmap[1].base = 1048576U; /* 1MB */
133 x86_memmap[1].length = info->mem_upper * 1024ULL;
134 x86_memmap[1].type = X86_MEMMAP_ENTRY_RAM;
135 clear_memmap(2);
136 }
137
138 x86_memmap_source = X86_MEMMAP_SOURCE_MULTIBOOT_MEM;
139 }
140 #endif /* CONFIG_MULTIBOOT_MEMMAP */
141 }
142
