1 /* Support for Multiboot */
2
3 #include "config.h"
4 #include "asm/io.h"
5 #include "libopenbios/sys_info.h"
6 #include "multiboot.h"
7
8 #ifdef CONFIG_DEBUG_BOOT
9 #define debug printk
10 #else
11 #define debug(x...)
12 #endif
13
14 struct mbheader {
15 unsigned int magic, flags, checksum;
16 };
17
18 const struct mbheader multiboot_header
19 __attribute__((section (".hdr"))) =
20 {
21 MULTIBOOT_HEADER_MAGIC,
22 MULTIBOOT_HEADER_FLAGS,
23 -(MULTIBOOT_HEADER_MAGIC + MULTIBOOT_HEADER_FLAGS)
24 };
25
26 /* Multiboot information structure, provided by loader to us */
27
28 struct multiboot_mmap {
29 unsigned entry_size;
30 unsigned base_lo, base_hi;
31 unsigned size_lo, size_hi;
32 unsigned type;
33 };
34
35 #define MULTIBOOT_MEM_VALID 0x01
36 #define MULTIBOOT_BOOT_DEV_VALID 0x02
37 #define MULTIBOOT_CMDLINE_VALID 0x04
38 #define MULTIBOOT_MODS_VALID 0x08
39 #define MULTIBOOT_AOUT_SYMS_VALID 0x10
40 #define MULTIBOOT_ELF_SYMS_VALID 0x20
41 #define MULTIBOOT_MMAP_VALID 0x40
42
43 void collect_multiboot_info(struct sys_info *info);
collect_multiboot_info(struct sys_info * info)44 void collect_multiboot_info(struct sys_info *info)
45 {
46 struct multiboot_info *mbinfo;
47 struct multiboot_mmap *mbmem;
48 unsigned mbcount, mbaddr;
49 int i;
50 struct memrange *mmap;
51 int mmap_count;
52 module_t *mod;
53
54 if (info->boot_type != 0x2BADB002)
55 return;
56
57 debug("Using Multiboot information at %#lx\n", info->boot_data);
58
59 mbinfo = phys_to_virt(info->boot_data);
60
61 if (mbinfo->mods_count != 1) {
62 printk("multiboot: no dictionary\n");
63 return;
64 }
65
66 mod = (module_t *) mbinfo->mods_addr;
67 info->dict_start=(unsigned long *)mod->mod_start;
68 info->dict_end=(unsigned long *)mod->mod_end;
69 debug("multiboot: dictionary at %p-%p\n",
70 info->dict_start, info->dict_end);
71
72 if (mbinfo->flags & MULTIBOOT_MMAP_VALID) {
73 /* convert mmap records */
74 mbmem = phys_to_virt(mbinfo->mmap_addr);
75 mbcount = mbinfo->mmap_length / (mbmem->entry_size + 4);
76 mmap = malloc(mbcount * sizeof(struct memrange));
77 mmap_count = 0;
78 mbaddr = mbinfo->mmap_addr;
79 for (i = 0; i < mbcount; i++) {
80 mbmem = phys_to_virt(mbaddr);
81 debug("%08x%08x %08x%08x (%d)\n",
82 mbmem->base_hi,
83 mbmem->base_lo,
84 mbmem->size_hi,
85 mbmem->size_lo,
86 mbmem->type);
87 if (mbmem->type == 1) { /* Only normal RAM */
88 mmap[mmap_count].base = mbmem->base_lo
89 + (((unsigned long long) mbmem->base_hi) << 32);
90 mmap[mmap_count].size = mbmem->size_lo
91 + (((unsigned long long) mbmem->size_hi) << 32);
92 mmap_count++;
93 }
94 mbaddr += mbmem->entry_size + 4;
95 if (mbaddr >= mbinfo->mmap_addr + mbinfo->mmap_length)
96 break;
97 }
98 /* simple sanity check - there should be at least 2 RAM segments
99 * (base 640k and extended) */
100 if (mmap_count >= 2)
101 goto got_it;
102
103 printk("Multiboot mmap is broken\n");
104 free(mmap);
105 /* fall back to mem_lower/mem_upper */
106 }
107
108 if (mbinfo->flags & MULTIBOOT_MEM_VALID) {
109 /* use mem_lower and mem_upper */
110 mmap_count = 2;
111 mmap = malloc(2 * sizeof(*mmap));
112 mmap[0].base = 0;
113 mmap[0].size = mbinfo->mem_lower << 10;
114 mmap[1].base = 1 << 20; /* 1MB */
115 mmap[1].size = mbinfo->mem_upper << 10;
116 goto got_it;
117 }
118
119 printk("Can't get memory information from Multiboot\n");
120 return;
121
122 got_it:
123 info->memrange = mmap;
124 info->n_memranges = mmap_count;
125
126 return;
127 }
128