3
* Supports bzImage, zImage and Image format.
5
* Based on work by Steve Gehlbach.
6
* Portions are taken from mkelfImage.
8
* 2003-09 by SONE Takeshi
12
#include "kernel/kernel.h"
13
#include "libopenbios/bindings.h"
14
#include "libopenbios/sys_info.h"
21
#define strtoull_with_suffix strtol
23
#define LINUX_PARAM_LOC 0x90000
24
#define COMMAND_LINE_LOC 0x91000
25
#define GDT_LOC 0x92000
26
#define STACK_LOC 0x93000
28
#define E820MAX 32 /* number of entries in E820MAP */
30
unsigned long long addr; /* start of memory segment */
31
unsigned long long size; /* size of memory segment */
32
unsigned long type; /* type of memory segment */
34
#define E820_RESERVED 2
35
#define E820_ACPI 3 /* usable as RAM once ACPI tables have been read */
39
/* The header of Linux/i386 kernel */
41
uint8_t reserved1[0x1f1]; /* 0x000 */
42
uint8_t setup_sects; /* 0x1f1 */
43
uint16_t root_flags; /* 0x1f2 */
44
uint8_t reserved2[6]; /* 0x1f4 */
45
uint16_t vid_mode; /* 0x1fa */
46
uint16_t root_dev; /* 0x1fc */
47
uint16_t boot_sector_magic; /* 0x1fe */
49
uint8_t reserved3[2]; /* 0x200 */
50
uint8_t header_magic[4]; /* 0x202 */
51
uint16_t protocol_version; /* 0x206 */
52
uint32_t realmode_swtch; /* 0x208 */
53
uint16_t start_sys; /* 0x20c */
54
uint16_t kver_addr; /* 0x20e */
55
uint8_t type_of_loader; /* 0x210 */
56
uint8_t loadflags; /* 0x211 */
57
uint16_t setup_move_size; /* 0x212 */
58
uint32_t code32_start; /* 0x214 */
59
uint32_t ramdisk_image; /* 0x218 */
60
uint32_t ramdisk_size; /* 0x21c */
61
uint8_t reserved4[4]; /* 0x220 */
63
uint16_t heap_end_ptr; /* 0x224 */
64
uint8_t reserved5[2]; /* 0x226 */
66
uint32_t cmd_line_ptr; /* 0x228 */
68
uint32_t initrd_addr_max; /* 0x22c */
69
} __attribute__ ((packed));
72
/* Paramters passed to 32-bit part of Linux
73
* This is another view of the structure above.. */
75
uint8_t orig_x; /* 0x00 */
76
uint8_t orig_y; /* 0x01 */
77
uint16_t ext_mem_k; /* 0x02 -- EXT_MEM_K sits here */
78
uint16_t orig_video_page; /* 0x04 */
79
uint8_t orig_video_mode; /* 0x06 */
80
uint8_t orig_video_cols; /* 0x07 */
81
uint16_t unused2; /* 0x08 */
82
uint16_t orig_video_ega_bx; /* 0x0a */
83
uint16_t unused3; /* 0x0c */
84
uint8_t orig_video_lines; /* 0x0e */
85
uint8_t orig_video_isVGA; /* 0x0f */
86
uint16_t orig_video_points; /* 0x10 */
88
/* VESA graphic mode -- linear frame buffer */
89
uint16_t lfb_width; /* 0x12 */
90
uint16_t lfb_height; /* 0x14 */
91
uint16_t lfb_depth; /* 0x16 */
92
uint32_t lfb_base; /* 0x18 */
93
uint32_t lfb_size; /* 0x1c */
94
uint16_t cl_magic; /* 0x20 */
95
#define CL_MAGIC_VALUE 0xA33F
96
uint16_t cl_offset; /* 0x22 */
97
uint16_t lfb_linelength; /* 0x24 */
98
uint8_t red_size; /* 0x26 */
99
uint8_t red_pos; /* 0x27 */
100
uint8_t green_size; /* 0x28 */
101
uint8_t green_pos; /* 0x29 */
102
uint8_t blue_size; /* 0x2a */
103
uint8_t blue_pos; /* 0x2b */
104
uint8_t rsvd_size; /* 0x2c */
105
uint8_t rsvd_pos; /* 0x2d */
106
uint16_t vesapm_seg; /* 0x2e */
107
uint16_t vesapm_off; /* 0x30 */
108
uint16_t pages; /* 0x32 */
109
uint8_t reserved4[12]; /* 0x34 -- 0x3f reserved for future expansion */
111
//struct apm_bios_info apm_bios_info; /* 0x40 */
112
uint8_t apm_bios_info[0x40];
113
//struct drive_info_struct drive_info; /* 0x80 */
114
uint8_t drive_info[0x20];
115
//struct sys_desc_table sys_desc_table; /* 0xa0 */
116
uint8_t sys_desc_table[0x140];
117
uint32_t alt_mem_k; /* 0x1e0 */
118
uint8_t reserved5[4]; /* 0x1e4 */
119
uint8_t e820_map_nr; /* 0x1e8 */
120
uint8_t reserved6[9]; /* 0x1e9 */
121
uint16_t mount_root_rdonly; /* 0x1f2 */
122
uint8_t reserved7[4]; /* 0x1f4 */
123
uint16_t ramdisk_flags; /* 0x1f8 */
124
#define RAMDISK_IMAGE_START_MASK 0x07FF
125
#define RAMDISK_PROMPT_FLAG 0x8000
126
#define RAMDISK_LOAD_FLAG 0x4000
127
uint8_t reserved8[2]; /* 0x1fa */
128
uint16_t orig_root_dev; /* 0x1fc */
129
uint8_t reserved9[1]; /* 0x1fe */
130
uint8_t aux_device_info; /* 0x1ff */
131
uint8_t reserved10[2]; /* 0x200 */
132
uint8_t param_block_signature[4]; /* 0x202 */
133
uint16_t param_block_version; /* 0x206 */
134
uint8_t reserved11[8]; /* 0x208 */
135
uint8_t loader_type; /* 0x210 */
136
#define LOADER_TYPE_LOADLIN 1
137
#define LOADER_TYPE_BOOTSECT_LOADER 2
138
#define LOADER_TYPE_SYSLINUX 3
139
#define LOADER_TYPE_ETHERBOOT 4
140
#define LOADER_TYPE_KERNEL 5
141
uint8_t loader_flags; /* 0x211 */
142
uint8_t reserved12[2]; /* 0x212 */
143
uint32_t kernel_start; /* 0x214 */
144
uint32_t initrd_start; /* 0x218 */
145
uint32_t initrd_size; /* 0x21c */
146
uint8_t reserved12_5[8]; /* 0x220 */
147
uint32_t cmd_line_ptr; /* 0x228 */
148
uint8_t reserved13[164]; /* 0x22c */
149
struct e820entry e820_map[E820MAX]; /* 0x2d0 */
150
uint8_t reserved16[688]; /* 0x550 */
151
#define COMMAND_LINE_SIZE 256
152
/* Command line is copied here by 32-bit i386/kernel/head.S.
153
* So I will follow the boot protocol, rather than putting it
154
* directly here. --ts1 */
155
uint8_t command_line[COMMAND_LINE_SIZE]; /* 0x800 */
156
uint8_t reserved17[1792]; /* 0x900 - 0x1000 */
159
uint64_t forced_memsize;
161
/* Load the first part the file and check if it's Linux */
162
static uint32_t load_linux_header(struct linux_header *hdr)
167
if (lfile_read(hdr, sizeof *hdr) != sizeof *hdr) {
168
debug("Can't read Linux header\n");
171
if (hdr->boot_sector_magic != 0xaa55) {
172
debug("Not a Linux kernel image\n");
176
/* Linux is found. Print some information */
177
if (memcmp(hdr->header_magic, "HdrS", 4) != 0) {
178
/* This may be floppy disk image or something.
179
* Perform a simple (incomplete) sanity check. */
180
if (hdr->setup_sects >= 16
181
|| file_size() - (hdr->setup_sects<<9) >= 512<<10) {
182
debug("This looks like a bootdisk image but not like Linux...\n");
186
printf("Possible very old Linux");
187
/* This kernel does not even have a protocol version.
188
* Force the value. */
189
hdr->protocol_version = 0; /* pre-2.00 */
191
printf("Found Linux");
192
if (hdr->protocol_version >= 0x200 && hdr->kver_addr) {
194
file_seek(hdr->kver_addr + 0x200);
195
if (lfile_read(kver, sizeof kver) != 0) {
197
printf(" version %s", kver);
200
debug(" (protocol %#x)", hdr->protocol_version);
202
if (hdr->protocol_version >= 0x200) {
203
debug(" (loadflags %#x)", hdr->loadflags);
204
load_high = hdr->loadflags & 1;
208
kern_addr = 0x100000;
210
printf(" zImage or Image");
218
/* Set up parameters for 32-bit kernel */
220
init_linux_params(struct linux_params *params, struct linux_header *hdr)
222
debug("Setting up parameters at %#lx\n", virt_to_phys(params));
223
memset(params, 0, sizeof *params);
225
/* Copy some useful values from header */
226
params->mount_root_rdonly = hdr->root_flags;
227
params->orig_root_dev = hdr->root_dev;
230
* This assumes we have VGA in standard 80x25 text mode,
231
* just like our vga.c does.
232
* Cursor position is filled later to allow some more printf's. */
233
params->orig_video_mode = 3;
234
params->orig_video_cols = 80;
235
params->orig_video_lines = 25;
236
params->orig_video_isVGA = 1;
237
params->orig_video_points = 16;
239
params->loader_type = 0xff; /* Unregistered Linux loader */
244
set_memory_size(struct linux_params *params, struct sys_info *info)
249
struct e820entry *linux_map;
250
struct memrange *filo_map;
252
linux_map = params->e820_map;
253
filo_map = info->memrange;
254
for (i = 0; i < info->n_memranges; i++, linux_map++, filo_map++) {
256
/* Convert to BIOS e820 style */
257
linux_map->addr = filo_map->base;
258
linux_map->size = filo_map->size;
259
linux_map->type = E820_RAM;
260
debug("%016Lx - %016Lx\n", linux_map->addr,
261
linux_map->addr + linux_map->size);
262
params->e820_map_nr = i+1;
265
/* Find out top of RAM. XXX This ignores hole above 1MB */
266
end = filo_map->base + filo_map->size;
267
if (end < (1ULL << 32)) { /* don't count memory above 4GB */
269
ramtop = (uint32_t) end;
272
debug("ramtop=%#x\n", ramtop);
273
/* Size of memory above 1MB in KB */
274
params->alt_mem_k = (ramtop - (1<<20)) >> 10;
275
/* old style, 64MB max */
276
if (ramtop >= (64<<20))
277
params->ext_mem_k = (63<<10);
279
params->ext_mem_k = params->alt_mem_k;
280
debug("ext_mem_k=%d, alt_mem_k=%d\n", params->ext_mem_k, params->alt_mem_k);
285
* Some parameters, like initrd=<file>, are not passed to kernel,
286
* we are responsible to process them.
287
* Parameters for kernel are copied to kern_cmdline. Returns name of initrd.
289
static char *parse_command_line(const char *orig_cmdline, char *kern_cmdline)
291
const char *start, *sep, *end, *val;
307
debug("original command line: \"%s\"\n", orig_cmdline);
308
debug("kernel command line at %#lx\n", virt_to_phys(kern_cmdline));
310
start = orig_cmdline;
311
while (*start == ' ')
314
end = strchr(start, ' ');
316
end = start + strlen(start);
317
sep = strchr(start, '=');
318
if (!sep || sep > end)
321
if (len >= sizeof(name))
322
len = sizeof(name) - 1;
323
memcpy(name, start, len);
334
/* Only initrd= and mem= are handled here. vga= is not,
335
* which I believe is a paramter to the realmode part of Linux,
336
* which we don't execute. */
337
if (strcmp(name, "initrd") == 0) {
339
printf("Missing filename to initrd parameter\n");
341
initrd = malloc(len + 1);
342
memcpy(initrd, val, len);
344
debug("initrd=%s\n", initrd);
346
/* Don't pass this to kernel */
348
} else if (strcmp(name, "mem") == 0) {
350
printf("Missing value for mem parameter\n");
352
forced_memsize = strtoull_with_suffix(val, (char**)&val, 0);
353
if (forced_memsize == 0)
354
printf("Invalid mem option, ignored\n");
356
printf("Garbage after mem=<size>, ignored\n");
359
debug("mem=%Lu\n", forced_memsize);
361
/* mem= is for both loader and kernel */
367
/* Copy to kernel command line buffer */
369
kern_cmdline[k_len++] = ' '; /* put separator */
371
if (k_len + len >= COMMAND_LINE_SIZE) {
372
len = COMMAND_LINE_SIZE - k_len - 1;
374
printf("Kernel command line is too long; truncated to "
375
"%d bytes\n", COMMAND_LINE_SIZE-1);
379
memcpy(kern_cmdline + k_len, start, len);
384
while (*start == ' ')
387
kern_cmdline[k_len] = 0;
388
debug("kernel command line (%d bytes): \"%s\"\n", k_len, kern_cmdline);
393
/* Set command line location */
394
static void set_command_line_loc(struct linux_params *params,
395
struct linux_header *hdr)
397
if (hdr->protocol_version >= 0x202) {
399
params->cmd_line_ptr = COMMAND_LINE_LOC;
402
params->cl_magic = CL_MAGIC_VALUE;
403
params->cl_offset = COMMAND_LINE_LOC - LINUX_PARAM_LOC;
407
/* Load 32-bit part of kernel */
408
static int load_linux_kernel(struct linux_header *hdr, uint32_t kern_addr)
410
uint32_t kern_offset, kern_size;
412
if (hdr->setup_sects == 0)
413
hdr->setup_sects = 4;
414
kern_offset = (hdr->setup_sects + 1) * 512;
415
file_seek(kern_offset);
416
kern_size = file_size() - kern_offset;
417
debug("offset=%#x addr=%#x size=%#x\n", kern_offset, kern_addr, kern_size);
421
printf("Attempt to load up to end of device as kernel; "
422
"specify the image size\n");
427
printf("Loading kernel... ");
428
if (lfile_read(phys_to_virt(kern_addr), kern_size) != kern_size) {
429
printf("Can't read kernel\n");
437
static int load_initrd(struct linux_header *hdr, struct sys_info *info,
438
uint32_t kern_end, struct linux_params *params, const char *initrd_file)
441
uint32_t start, end, size;
443
extern char _start[], _end[];
445
if (!file_open(initrd_file)) {
446
printf("Can't open initrd: %s\n", initrd_file);
452
printf("Attempt to load up to end of device as initrd; "
453
"specify the image size\n");
461
/* Find out the kernel's restriction on how high the initrd can be
463
if (hdr->protocol_version >= 0x203)
464
max = hdr->initrd_addr_max;
466
max = 0x38000000; /* Hardcoded value for older kernels */
468
/* FILO itself is at the top of RAM. (relocated)
469
* So, try putting initrd just below us. */
470
end = virt_to_phys(_start);
474
/* If "mem=" option is given, we have to put the initrd within
475
* the specified range. */
476
if (forced_memsize) {
477
forced = forced_memsize;
480
/* If the "mem=" is lower, it's easy */
484
/* Otherwise, see if we can put it above us */
485
if (virt_to_phys(_end) + size <= forced)
486
end = forced; /* Ok */
491
start &= ~0xfff; /* page align */
494
debug("start=%#x end=%#x\n", start, end);
496
if (start < kern_end) {
497
printf("Initrd is too big to fit in memory\n");
501
printf("Loading initrd... ");
502
if (lfile_read(phys_to_virt(start), size) != size) {
503
printf("Can't read initrd\n");
508
params->initrd_start = start;
509
params->initrd_size = size;
514
static void hardware_setup(void)
519
/* Make sure any coprocessor is properly reset.. */
523
/* we're getting screwed again and again by this problem of the 8259.
524
* so we're going to leave this lying around for inclusion into
525
* crt0.S on an as-needed basis.
527
* well, that went ok, I hope. Now we have to reprogram the interrupts :-(
528
* we put them right after the intel-reserved hardware interrupts, at
529
* int 0x20-0x2F. There they won't mess up anything. Sadly IBM really
530
* messed this up with the original PC, and they haven't been able to
531
* rectify it afterwards. Thus the bios puts interrupts at 0x08-0x0f,
532
* which is used for the internal hardware interrupts as well. We just
533
* have to reprogram the 8259's, and it isn't fun.
536
outb(0x11, 0x20); /* initialization sequence to 8259A-1 */
537
outb(0x11, 0xA0); /* and to 8259A-2 */
539
outb(0x20, 0x21); /* start of hardware int's (0x20) */
540
outb(0x28, 0xA1); /* start of hardware int's 2 (0x28) */
542
outb(0x04, 0x21); /* 8259-1 is master */
543
outb(0x02, 0xA1); /* 8259-2 is slave */
545
outb(0x01, 0x21); /* 8086 mode for both */
548
outb(0xFF, 0xA1); /* mask off all interrupts for now */
549
outb(0xFB, 0x21); /* mask all irq's but irq2 which is cascaded */
553
static int start_linux(uint32_t kern_addr, struct linux_params *params)
555
struct segment_desc *linux_gdt;
557
//extern int cursor_x, cursor_y;
559
ctx = init_context(phys_to_virt(STACK_LOC), 4096, 0);
561
/* Linux expects GDT being in low memory */
562
linux_gdt = phys_to_virt(GDT_LOC);
563
memset(linux_gdt, 0, 13*sizeof(struct segment_desc));
564
/* Normal kernel code/data segments */
565
linux_gdt[2] = gdt[FLAT_CODE];
566
linux_gdt[3] = gdt[FLAT_DATA];
567
/* 2.6 kernel uses 12 and 13, but head.S uses backward-compatible
568
* segments (2 and 3), so it SHOULD not be a problem.
569
* However, some distro kernels (eg. RH9) with backported threading
570
* patch use 12 and 13 also when booting... */
571
linux_gdt[12] = gdt[FLAT_CODE];
572
linux_gdt[13] = gdt[FLAT_DATA];
573
ctx->gdt_base = GDT_LOC;
574
ctx->gdt_limit = 14*8-1;
582
/* Parameter location */
583
ctx->esi = virt_to_phys(params);
586
ctx->eip = kern_addr;
588
debug("eip=%#x\n", kern_addr);
589
printf("Jumping to entry point...\n");
592
/* Update VGA cursor position.
593
* This must be here because the printf changes the value! */
594
params->orig_x = cursor_x;
595
params->orig_y = cursor_y;
599
ctx = switch_to(ctx);
601
/* It's impossible but... */
602
printf("Returned with eax=%#x\n", ctx->eax);
607
int linux_load(struct sys_info *info, const char *file, const char *cmdline)
609
struct linux_header hdr;
610
struct linux_params *params;
611
uint32_t kern_addr, kern_size;
612
char *initrd_file = 0;
614
if (!file_open(file))
617
kern_addr = load_linux_header(&hdr);
619
return LOADER_NOT_SUPPORT;
621
params = phys_to_virt(LINUX_PARAM_LOC);
622
init_linux_params(params, &hdr);
623
set_memory_size(params, info);
624
initrd_file = parse_command_line(cmdline, phys_to_virt(COMMAND_LINE_LOC));
625
set_command_line_loc(params, &hdr);
627
kern_size = load_linux_kernel(&hdr, kern_addr);
628
if (kern_size == 0) {
635
if (load_initrd(&hdr, info, kern_addr+kern_size, params, initrd_file)
645
start_linux(kern_addr, params);