以下代码来自testasecca的boot-patch for 89712 http://ttestasecca.free.fr/cdb89712/patch/boot_patch cdb89712/kernel/arch/boot/compressed/misc.c
int hermit_linux_cmdfunc(int argc, char *argv[]) {
struct tag *tag = (struct tag *) LINUX_PARAM_ADDRESS;
/* zero param block */
memzero (tag, LINUX_PARAM_SIZE);
/* set up core tag */
tag->hdr.tag = ATAG_CORE;
tag->hdr.size = tag_size(tag_core); tag->u.core.flags = 0;
tag->u.core.pagesize = 0x1000;
tag->u.core.rootdev = MKDEV(MTD_MAJOR, MTD_MINOR);
/* 16 MB of SDRAM at 0xc0000000 */ tag = tag_next(tag);
tag->hdr.tag = ATAG_MEM;
tag->hdr.size = tag_size(tag_mem32); tag->u.mem.size = DRAM1_SIZE >> 12; tag->u.mem.start = DRAM1_START;
/* an initial ramdisk image in flash at 0x00700000 */
/* tag = tag_next(tag);
tag->hdr.tag = ATAG_INITRD;
tag->hdr.size = tag_size(tag_initrd);
tag->u.initrd.start = INITRD_LOAD_ADDRESS; tag->u.initrd.size = INITRD_SIZE; */ /* the command line arguments */
/* if (argc > 1) {
tag = tag_next(tag);
tag->hdr.tag = ATAG_CMDLINE;
tag->hdr.size = (COMMAND_LINE_SIZE + 3 + sizeof(struct tag_header)) >> 2;
{
const unsigned char *src; unsigned char *dst;
dst = tag->u.cmdline.cmdline;
memzero (dst, COMMAND_LINE_SIZE); while (--argc > 0) { src = *++argv;
hprintf (\ while (*src)
*dst++ = *src++; *dst++ = ' '; }
*--dst = '\\0'; } }
*/
tag = tag_next(tag); tag->hdr.tag = 0; tag->hdr.size = 0;
/* branch to kernel image */ __asm__ volatile (
\
\ \
\ \ \
// \ );
/* never get here */ return 0; }
以下来自VIVI/lib/boot_kernel.c
static void setup_linux_param(ulong param_base) { struct param_struct *params = (struct param_struct *)param_base; char *linux_cmd; printk(\ memset(params, 0, sizeof(struct param_struct)); /* 2??à?á ??áà?? μé °íμé.. 3-μe°? °??èà?à?·? ′??? ??ào °í.. */ params->u1.s.page_size = LINUX_PAGE_SIZE; params->u1.s.nr_pages = (DRAM_SIZE >> LINUX_PAGE_SHIFT);
#if 0
#endif
params->u1.s.page_size = LINUX_PAGE_SIZE;
params->u1.s.nr_pages = (dram_size >> LINUX_PAGE_SHIFT); params->u1.s.ramdisk_size = 0; params->u1.s.rootdev = rootdev; params->u1.s.flags = 0; /* TODO */
/* If use ramdisk */ /*
params->u1.s.initrd_start = ?; params->u1.s.initrd_size = ?; params->u1.s.rd_start = ?; */
}
/* set linux command line */
linux_cmd = get_linux_cmd_line(); if (linux_cmd == NULL) { printk(\} else { memcpy(params->commandline, linux_cmd, strlen(linux_cmd) + 1); printk(\ }
附录 struct param_struct解释 asm-arm/setup.h
/* This is the old deprecated way to pass parameters to the kernel */
struct param_struct { union { struct {
unsigned long page_size; /* 0 */ unsigned long nr_pages; /* 4 */ unsigned long ramdisk_size; /* 8 */ unsigned long flags; /* 12 */ #define FLAG_READONLY 1 #define FLAG_RDLOAD 4 #define FLAG_RDPROMPT 8
unsigned long rootdev; /* 16 */ unsigned long video_num_cols; /* 20 */ unsigned long video_num_rows; /* 24 */ unsigned long video_x; /* 28 */ unsigned long video_y; /* 32 */
unsigned long memc_control_reg; /* 36 */ unsigned char sounddefault; /* 40 */ unsigned char adfsdrives; /* 41 */ unsigned char bytes_per_char_h; /* 42 */ unsigned char bytes_per_char_v; /* 43 */ unsigned long pages_in_bank[4]; /* 44 */ unsigned long pages_in_vram; /* 60 */ unsigned long initrd_start; /* 64 */ unsigned long initrd_size; /* 68 */ unsigned long rd_start; /* 72 */ unsigned long system_rev; /* 76 */ unsigned long system_serial_low; /* 80 */ unsigned long system_serial_high; /* 84 */ unsigned long mem_fclk_21285; /* 88 */ } s;
char unused[256]; } u1; union {
char paths[8][128]; struct {
unsigned long magic;
char n[1024 - sizeof(unsigned long)]; } s; } u2;
char commandline[COMMAND_LINE_SIZE]; };
Kernel initialisation parameters on ARM Linux ---------------------------------------------
The following document describes the kernel initialisation parameter structure, otherwise known as 'struct param_struct' which is used for most ARM Linux architectures.
This structure is used to pass initialisation parameters from the kernel loader to the Linux kernel proper, and may be short lived through the kernel initialisation process. As a general rule, it
should not be referenced outside of arch/arm/kernel/setup.c:setup_arch().
There are a lot of parameters listed in there, and they are described below:
page_size
This parameter must be set to the page size of the machine, and will be checked by the kernel.
nr_pages
This is the total number of pages of memory in the system. If the memory is banked, then this should contain the total number of pages in the system.
If the system contains separate VRAM, this value should not include this information.
ramdisk_size
This is now obsolete, and should not be used.
flags
Various kernel flags, including: bit 0 - 1 = mount root read only bit 1 - unused
bit 2 - 0 = load ramdisk
bit 3 - 0 = prompt for ramdisk
rootdev
major/minor number pair of device to mount as the root filesystem.
video_num_cols video_num_rows
These two together describe the character size of the dummy console, or VGA console character size. They should not be used for any other purpose.
It's generally a good idea to set these to be either standard VGA, or the equivalent character size of your fbcon display. This then allows all the bootup messages to be displayed correctly.
video_x video_y
This describes the character position of cursor on VGA console, and is otherwise unused. (should not used for other console types, and should not be used for other purposes).
memc_control_reg
MEMC chip control register for Acorn Archimedes and Acorn A5000 based machines. May be used differently by different architectures.
sounddefault
Default sound setting on Acorn machines. May be used differently by different architectures.
adfsdrives
Number of ADFS/MFM disks. May be used differently by different architectures.
bytes_per_char_h bytes_per_char_v
These are now obsolete, and should not be used.
pages_in_bank[4]
Number of pages in each bank of the systems memory (used for RiscPC). This is intended to be used on systems where the physical memory is non-contiguous from the processors point of view.
pages_in_vram
Number of pages in VRAM (used on Acorn RiscPC). This value may also be used by loaders if the size of the video RAM can't be obtained from the hardware.
initrd_start initrd_size
