WSL2-Linux-Kernel/arch/powerpc/boot/main.c

312 строки
8.5 KiB
C

/*
* Copyright (C) Paul Mackerras 1997.
*
* Updates for PPC64 by Todd Inglett, Dave Engebretsen & Peter Bergner.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <stdarg.h>
#include <stddef.h>
#include "elf.h"
#include "page.h"
#include "string.h"
#include "stdio.h"
#include "ops.h"
#include "gunzip_util.h"
#include "flatdevtree.h"
extern void flush_cache(void *, unsigned long);
extern char _start[];
extern char __bss_start[];
extern char _end[];
extern char _vmlinux_start[];
extern char _vmlinux_end[];
extern char _initrd_start[];
extern char _initrd_end[];
extern char _dtb_start[];
extern char _dtb_end[];
static struct gunzip_state gzstate;
struct addr_range {
void *addr;
unsigned long size;
};
struct elf_info {
unsigned long loadsize;
unsigned long memsize;
unsigned long elfoffset;
};
typedef void (*kernel_entry_t)(unsigned long, unsigned long, void *);
#undef DEBUG
static int parse_elf64(void *hdr, struct elf_info *info)
{
Elf64_Ehdr *elf64 = hdr;
Elf64_Phdr *elf64ph;
unsigned int i;
if (!(elf64->e_ident[EI_MAG0] == ELFMAG0 &&
elf64->e_ident[EI_MAG1] == ELFMAG1 &&
elf64->e_ident[EI_MAG2] == ELFMAG2 &&
elf64->e_ident[EI_MAG3] == ELFMAG3 &&
elf64->e_ident[EI_CLASS] == ELFCLASS64 &&
elf64->e_ident[EI_DATA] == ELFDATA2MSB &&
elf64->e_type == ET_EXEC &&
elf64->e_machine == EM_PPC64))
return 0;
elf64ph = (Elf64_Phdr *)((unsigned long)elf64 +
(unsigned long)elf64->e_phoff);
for (i = 0; i < (unsigned int)elf64->e_phnum; i++, elf64ph++)
if (elf64ph->p_type == PT_LOAD)
break;
if (i >= (unsigned int)elf64->e_phnum)
return 0;
info->loadsize = (unsigned long)elf64ph->p_filesz;
info->memsize = (unsigned long)elf64ph->p_memsz;
info->elfoffset = (unsigned long)elf64ph->p_offset;
return 1;
}
static int parse_elf32(void *hdr, struct elf_info *info)
{
Elf32_Ehdr *elf32 = hdr;
Elf32_Phdr *elf32ph;
unsigned int i;
if (!(elf32->e_ident[EI_MAG0] == ELFMAG0 &&
elf32->e_ident[EI_MAG1] == ELFMAG1 &&
elf32->e_ident[EI_MAG2] == ELFMAG2 &&
elf32->e_ident[EI_MAG3] == ELFMAG3 &&
elf32->e_ident[EI_CLASS] == ELFCLASS32 &&
elf32->e_ident[EI_DATA] == ELFDATA2MSB &&
elf32->e_type == ET_EXEC &&
elf32->e_machine == EM_PPC))
return 0;
elf32ph = (Elf32_Phdr *) ((unsigned long)elf32 + elf32->e_phoff);
for (i = 0; i < elf32->e_phnum; i++, elf32ph++)
if (elf32ph->p_type == PT_LOAD)
break;
if (i >= elf32->e_phnum)
return 0;
info->loadsize = elf32ph->p_filesz;
info->memsize = elf32ph->p_memsz;
info->elfoffset = elf32ph->p_offset;
return 1;
}
static struct addr_range prep_kernel(void)
{
char elfheader[256];
void *vmlinuz_addr = _vmlinux_start;
unsigned long vmlinuz_size = _vmlinux_end - _vmlinux_start;
void *addr = 0;
struct elf_info ei;
int len;
/* gunzip the ELF header of the kernel */
gunzip_start(&gzstate, vmlinuz_addr, vmlinuz_size);
gunzip_exactly(&gzstate, elfheader, sizeof(elfheader));
if (!parse_elf64(elfheader, &ei) && !parse_elf32(elfheader, &ei)) {
printf("Error: not a valid PPC32 or PPC64 ELF file!\n\r");
exit();
}
if (platform_ops.image_hdr)
platform_ops.image_hdr(elfheader);
/* We need to alloc the memsize: gzip will expand the kernel
* text/data, then possible rubbish we don't care about. But
* the kernel bss must be claimed (it will be zero'd by the
* kernel itself)
*/
printf("Allocating 0x%lx bytes for kernel ...\n\r", ei.memsize);
if (platform_ops.vmlinux_alloc) {
addr = platform_ops.vmlinux_alloc(ei.memsize);
} else {
if ((unsigned long)_start < ei.memsize) {
printf("Insufficient memory for kernel at address 0!"
" (_start=%lx)\n\r", _start);
exit();
}
}
/* Finally, gunzip the kernel */
printf("gunzipping (0x%p <- 0x%p:0x%p)...", addr,
vmlinuz_addr, vmlinuz_addr+vmlinuz_size);
/* discard up to the actual load data */
gunzip_discard(&gzstate, ei.elfoffset - sizeof(elfheader));
len = gunzip_finish(&gzstate, addr, ei.memsize);
printf("done 0x%lx bytes\n\r", len);
flush_cache(addr, ei.loadsize);
return (struct addr_range){addr, ei.memsize};
}
static struct addr_range prep_initrd(struct addr_range vmlinux,
unsigned long initrd_addr,
unsigned long initrd_size)
{
void *devp;
u32 initrd_start, initrd_end;
/* If we have an image attached to us, it overrides anything
* supplied by the loader. */
if (_initrd_end > _initrd_start) {
printf("Attached initrd image at 0x%p-0x%p\n\r",
_initrd_start, _initrd_end);
initrd_addr = (unsigned long)_initrd_start;
initrd_size = _initrd_end - _initrd_start;
} else if (initrd_size > 0) {
printf("Using loader supplied ramdisk at 0x%lx-0x%lx\n\r",
initrd_addr, initrd_addr + initrd_size);
}
/* If there's no initrd at all, we're done */
if (! initrd_size)
return (struct addr_range){0, 0};
/*
* If the initrd is too low it will be clobbered when the
* kernel relocates to its final location. In this case,
* allocate a safer place and move it.
*/
if (initrd_addr < vmlinux.size) {
void *old_addr = (void *)initrd_addr;
printf("Allocating 0x%lx bytes for initrd ...\n\r",
initrd_size);
initrd_addr = (unsigned long)malloc(initrd_size);
if (! initrd_addr) {
printf("Can't allocate memory for initial "
"ramdisk !\n\r");
exit();
}
printf("Relocating initrd 0x%p <- 0x%p (0x%lx bytes)\n\r",
initrd_addr, old_addr, initrd_size);
memmove((void *)initrd_addr, old_addr, initrd_size);
}
printf("initrd head: 0x%lx\n\r", *((unsigned long *)initrd_addr));
/* Tell the kernel initrd address via device tree */
devp = finddevice("/chosen");
if (! devp) {
printf("Device tree has no chosen node!\n\r");
exit();
}
initrd_start = (u32)initrd_addr;
initrd_end = (u32)initrd_addr + initrd_size;
setprop(devp, "linux,initrd-start", &initrd_start,
sizeof(initrd_start));
setprop(devp, "linux,initrd-end", &initrd_end, sizeof(initrd_end));
return (struct addr_range){(void *)initrd_addr, initrd_size};
}
/* A buffer that may be edited by tools operating on a zImage binary so as to
* edit the command line passed to vmlinux (by setting /chosen/bootargs).
* The buffer is put in it's own section so that tools may locate it easier.
*/
static char builtin_cmdline[COMMAND_LINE_SIZE]
__attribute__((__section__("__builtin_cmdline")));
static void get_cmdline(char *buf, int size)
{
void *devp;
int len = strlen(builtin_cmdline);
buf[0] = '\0';
if (len > 0) { /* builtin_cmdline overrides dt's /chosen/bootargs */
len = min(len, size-1);
strncpy(buf, builtin_cmdline, len);
buf[len] = '\0';
}
else if ((devp = finddevice("/chosen")))
getprop(devp, "bootargs", buf, size);
}
static void set_cmdline(char *buf)
{
void *devp;
if ((devp = finddevice("/chosen")))
setprop(devp, "bootargs", buf, strlen(buf) + 1);
}
struct platform_ops platform_ops;
struct dt_ops dt_ops;
struct console_ops console_ops;
struct loader_info loader_info;
void start(void *sp)
{
struct addr_range vmlinux, initrd;
kernel_entry_t kentry;
char cmdline[COMMAND_LINE_SIZE];
unsigned long ft_addr = 0;
if (console_ops.open && (console_ops.open() < 0))
exit();
if (platform_ops.fixups)
platform_ops.fixups();
printf("\n\rzImage starting: loaded at 0x%p (sp: 0x%p)\n\r",
_start, sp);
vmlinux = prep_kernel();
initrd = prep_initrd(vmlinux, loader_info.initrd_addr,
loader_info.initrd_size);
/* If cmdline came from zimage wrapper or if we can edit the one
* in the dt, print it out and edit it, if possible.
*/
if ((strlen(builtin_cmdline) > 0) || console_ops.edit_cmdline) {
get_cmdline(cmdline, COMMAND_LINE_SIZE);
printf("\n\rLinux/PowerPC load: %s", cmdline);
if (console_ops.edit_cmdline)
console_ops.edit_cmdline(cmdline, COMMAND_LINE_SIZE);
printf("\n\r");
set_cmdline(cmdline);
}
printf("Finalizing device tree...");
if (dt_ops.finalize)
ft_addr = dt_ops.finalize();
if (ft_addr)
printf(" flat tree at 0x%lx\n\r", ft_addr);
else
printf(" using OF tree (promptr=%p)\n\r", loader_info.promptr);
if (console_ops.close)
console_ops.close();
kentry = (kernel_entry_t) vmlinux.addr;
if (ft_addr)
kentry(ft_addr, 0, NULL);
else
kentry((unsigned long)initrd.addr, initrd.size,
loader_info.promptr);
/* console closed so printf below may not work */
printf("Error: Linux kernel returned to zImage boot wrapper!\n\r");
exit();
}