/*
* Definitions and wrapper functions for kernel decompressor
*
* (C) 2017 Helge Deller <[email protected]>
*/
#include <linux/uaccess.h>
#include <linux/elf.h>
#include <asm/unaligned.h>
#include <asm/page.h>
#include "sizes.h"
/*
* gzip declarations
*/
#define STATIC static
#undef memmove
#define memmove memmove
#define memzero(s, n) memset((s), 0, (n))
#define malloc malloc_gzip
#define free free_gzip
/* Symbols defined by linker scripts */
extern char input_data[];
extern int input_len;
/* output_len is inserted by the linker possibly at an unaligned address */
extern char output_len;
extern char _text, _end;
extern char _bss, _ebss;
extern char _startcode_end;
extern void startup_continue(void *entry, unsigned long cmdline,
unsigned long rd_start, unsigned long rd_end) __noreturn;
void error(char *m) __noreturn;
static unsigned long free_mem_ptr;
static unsigned long free_mem_end_ptr;
#ifdef CONFIG_KERNEL_GZIP
#include "../../../../lib/decompress_inflate.c"
#endif
#ifdef CONFIG_KERNEL_BZIP2
#include "../../../../lib/decompress_bunzip2.c"
#endif
#ifdef CONFIG_KERNEL_LZ4
#include "../../../../lib/decompress_unlz4.c"
#endif
#ifdef CONFIG_KERNEL_LZMA
#include "../../../../lib/decompress_unlzma.c"
#endif
#ifdef CONFIG_KERNEL_LZO
#include "../../../../lib/decompress_unlzo.c"
#endif
#ifdef CONFIG_KERNEL_XZ
#include "../../../../lib/decompress_unxz.c"
#endif
void *memmove(void *dest, const void *src, size_t n)
{
const char *s = src;
char *d = dest;
if (d <= s) {
while (n--)
*d++ = *s++;
} else {
d += n;
s += n;
while (n--)
*--d = *--s;
}
return dest;
}
void *memset(void *s, int c, size_t count)
{
char *xs = (char *)s;
while (count--)
*xs++ = c;
return s;
}
void *memcpy(void *d, const void *s, size_t len)
{
char *dest = (char *)d;
const char *source = (const char *)s;
while (len--)
*dest++ = *source++;
return d;
}
size_t strlen(const char *s)
{
const char *sc;
for (sc = s; *sc != '\0'; ++sc)
;
return sc - s;
}
char *strchr(const char *s, int c)
{
while (*s) {
if (*s == (char)c)
return (char *)s;
++s;
}
return NULL;
}
static int puts(const char *s)
{
const char *nuline = s;
while ((nuline = strchr(s, '\n')) != NULL) {
if (nuline != s)
pdc_iodc_print(s, nuline - s);
pdc_iodc_print("\r\n", 2);
s = nuline + 1;
}
if (*s != '\0')
pdc_iodc_print(s, strlen(s));
return 0;
}
static int putchar(int c)
{
char buf[2];
buf[0] = c;
buf[1] = '\0';
puts(buf);
return c;
}
void __noreturn error(char *x)
{
if (x) puts(x);
puts("\n -- System halted\n");
while (1) /* wait forever */
;
}
static int print_num(unsigned long num, int base)
{
const char hex[] = "0123456789abcdef";
char str[40];
int i = sizeof(str)-1;
str[i--] = '\0';
do {
str[i--] = hex[num % base];
num = num / base;
} while (num);
if (base == 16) {
str[i--] = 'x';
str[i] = '0';
} else i++;
puts(&str[i]);
return 0;
}
static int printf(const char *fmt, ...)
{
va_list args;
int i = 0;
va_start(args, fmt);
while (fmt[i]) {
if (fmt[i] != '%') {
put:
putchar(fmt[i++]);
continue;
}
if (fmt[++i] == '%')
goto put;
print_num(va_arg(args, unsigned long),
fmt[i] == 'x' ? 16:10);
++i;
}
va_end(args);
return 0;
}
/* helper functions for libgcc */
void abort(void)
{
error("aborted.");
}
#undef malloc
static void *malloc(size_t size)
{
return malloc_gzip(size);
}
#undef free
static void free(void *ptr)
{
return free_gzip(ptr);
}
static void flush_data_cache(char *start, unsigned long length)
{
char *end = start + length;
do {
asm volatile("fdc 0(%0)" : : "r" (start));
asm volatile("fic 0(%%sr0,%0)" : : "r" (start));
start += 16;
} while (start < end);
asm volatile("fdc 0(%0)" : : "r" (end));
asm ("sync");
}
static void parse_elf(void *output)
{
#ifdef CONFIG_64BIT
Elf64_Ehdr ehdr;
Elf64_Phdr *phdrs, *phdr;
#else
Elf32_Ehdr ehdr;
Elf32_Phdr *phdrs, *phdr;
#endif
void *dest;
int i;
memcpy(&ehdr, output, sizeof(ehdr));
if (ehdr.e_ident[EI_MAG0] != ELFMAG0 ||
ehdr.e_ident[EI_MAG1] != ELFMAG1 ||
ehdr.e_ident[EI_MAG2] != ELFMAG2 ||
ehdr.e_ident[EI_MAG3] != ELFMAG3) {
error("Kernel is not a valid ELF file");
return;
}
#ifdef DEBUG
printf("Parsing ELF... ");
#endif
phdrs = malloc(sizeof(*phdrs) * ehdr.e_phnum);
if (!phdrs)
error("Failed to allocate space for phdrs");
memcpy(phdrs, output + ehdr.e_phoff, sizeof(*phdrs) * ehdr.e_phnum);
for (i = 0; i < ehdr.e_phnum; i++) {
phdr = &phdrs[i];
switch (phdr->p_type) {
case PT_LOAD:
dest = (void *)((unsigned long) phdr->p_paddr &
(__PAGE_OFFSET_DEFAULT-1));
memmove(dest, output + phdr->p_offset, phdr->p_filesz);
break;
default:
break;
}
}
free(phdrs);
}
asmlinkage unsigned long __visible decompress_kernel(unsigned int started_wide,
unsigned int command_line,
const unsigned int rd_start,
const unsigned int rd_end)
{
char *output;
unsigned long vmlinux_addr, vmlinux_len;
unsigned long kernel_addr, kernel_len;
#ifdef CONFIG_64BIT
parisc_narrow_firmware = 0;
#endif
set_firmware_width_unlocked();
putchar('D'); /* if you get this D and no more, string storage */
/* in $GLOBAL$ is wrong or %dp is wrong */
puts("ecompressing Linux... ");
/* where the final bits are stored */
kernel_addr = KERNEL_BINARY_TEXT_START;
kernel_len = __pa(SZ_end) - __pa(SZparisc_kernel_start);
if ((unsigned long) &_startcode_end > kernel_addr)
error("Bootcode overlaps kernel code");
/*
* Calculate addr to where the vmlinux ELF file shall be decompressed.
* Assembly code in head.S positioned the stack directly behind bss, so
* leave 2 MB for the stack.
*/
vmlinux_addr = (unsigned long) &_ebss + 2*1024*1024;
vmlinux_len = get_unaligned_le32(&output_len);
output = (char *) vmlinux_addr;
/*
* Initialize free_mem_ptr and free_mem_end_ptr.
*/
free_mem_ptr = vmlinux_addr + vmlinux_len;
/* Limit memory for bootoader to 1GB */
#define ARTIFICIAL_LIMIT (1*1024*1024*1024)
free_mem_end_ptr = PAGE0->imm_max_mem;
if (free_mem_end_ptr > ARTIFICIAL_LIMIT)
free_mem_end_ptr = ARTIFICIAL_LIMIT;
#ifdef CONFIG_BLK_DEV_INITRD
/* if we have ramdisk this is at end of memory */
if (rd_start && rd_start < free_mem_end_ptr)
free_mem_end_ptr = rd_start;
#endif
if (free_mem_ptr >= free_mem_end_ptr) {
int free_ram;
free_ram = (free_mem_ptr >> 20) + 1;
if (free_ram < 32)
free_ram = 32;
printf("\nKernel requires at least %d MB RAM.\n",
free_ram);
error(NULL);
}
#ifdef DEBUG
printf("\n");
printf("startcode_end = %x\n", &_startcode_end);
printf("commandline = %x\n", command_line);
printf("rd_start = %x\n", rd_start);
printf("rd_end = %x\n", rd_end);
printf("free_ptr = %x\n", free_mem_ptr);
printf("free_ptr_end = %x\n", free_mem_end_ptr);
printf("input_data = %x\n", input_data);
printf("input_len = %x\n", input_len);
printf("output = %x\n", output);
printf("output_len = %x\n", vmlinux_len);
printf("kernel_addr = %x\n", kernel_addr);
printf("kernel_len = %x\n", kernel_len);
#endif
__decompress(input_data, input_len, NULL, NULL,
output, 0, NULL, error);
parse_elf(output);
output = (char *) kernel_addr;
flush_data_cache(output, kernel_len);
printf("done.\nBooting the kernel.\n");
return (unsigned long) output;
}
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