# for more details.
#
# Copyright (C) 1994 by Linus Torvalds
+# Changed by many, many contributors over the years.
#
# ROOT_DEV specifies the default root-device when making the image.
# This can be either FLOPPY, CURRENT, /dev/xxxx or empty, in which case
# the default of FLOPPY is used by 'build'.
-ROOT_DEV := CURRENT
+ROOT_DEV := CURRENT
# If you want to preset the SVGA mode, uncomment the next line and
# set SVGA_MODE to whatever number you want.
# Set it to -DSVGA_MODE=NORMAL_VGA if you just want the EGA/VGA mode.
# The number is the same as you would ordinarily press at bootup.
-SVGA_MODE := -DSVGA_MODE=NORMAL_VGA
+SVGA_MODE := -DSVGA_MODE=NORMAL_VGA
-# If you want the RAM disk device, define this to be the size in blocks.
-
-#RAMDISK := -DRAMDISK=512
-
-targets := vmlinux.bin setup.bin setup.elf zImage bzImage
+targets := vmlinux.bin setup.bin setup.elf bzImage
subdir- := compressed
setup-y += a20.o cmdline.o copy.o cpu.o cpucheck.o edd.o
KBUILD_CFLAGS += $(call cc-option,-m32)
KBUILD_AFLAGS := $(KBUILD_CFLAGS) -D__ASSEMBLY__
-$(obj)/zImage: asflags-y := $(SVGA_MODE) $(RAMDISK)
-$(obj)/bzImage: ccflags-y := -D__BIG_KERNEL__
-$(obj)/bzImage: asflags-y := $(SVGA_MODE) $(RAMDISK) -D__BIG_KERNEL__
-$(obj)/bzImage: BUILDFLAGS := -b
+$(obj)/bzImage: asflags-y := $(SVGA_MODE)
quiet_cmd_image = BUILD $@
-cmd_image = $(obj)/tools/build $(BUILDFLAGS) $(obj)/setup.bin \
- $(obj)/vmlinux.bin $(ROOT_DEV) > $@
+cmd_image = $(obj)/tools/build $(obj)/setup.bin $(obj)/vmlinux.bin \
+ $(ROOT_DEV) > $@
-$(obj)/zImage $(obj)/bzImage: $(obj)/setup.bin \
- $(obj)/vmlinux.bin $(obj)/tools/build FORCE
+$(obj)/bzImage: $(obj)/setup.bin $(obj)/vmlinux.bin $(obj)/tools/build FORCE
$(call if_changed,image)
@echo 'Kernel: $@ is ready' ' (#'`cat .version`')'
#include "boot.h"
#include "offsets.h"
-SETUPSECTS = 4 /* default nr of setup-sectors */
BOOTSEG = 0x07C0 /* original address of boot-sector */
-SYSSEG = DEF_SYSSEG /* system loaded at 0x10000 (65536) */
-SYSSIZE = DEF_SYSSIZE /* system size: # of 16-byte clicks */
- /* to be loaded */
-ROOT_DEV = 0 /* ROOT_DEV is now written by "build" */
+SYSSEG = 0x1000 /* historical load address >> 4 */
#ifndef SVGA_MODE
#define SVGA_MODE ASK_VGA
.section ".header", "a"
.globl hdr
hdr:
-setup_sects: .byte SETUPSECTS
+setup_sects: .byte 0 /* Filled in by build.c */
root_flags: .word ROOT_RDONLY
-syssize: .long SYSSIZE
-ram_size: .word RAMDISK
+syssize: .long 0 /* Filled in by build.c */
+ram_size: .word 0 /* Obsolete */
vid_mode: .word SVGA_MODE
-root_dev: .word ROOT_DEV
+root_dev: .word 0 /* Filled in by build.c */
boot_flag: .word 0xAA55
# offset 512, entry point
# or else old loadlin-1.5 will fail)
.globl realmode_swtch
realmode_swtch: .word 0, 0 # default_switch, SETUPSEG
-start_sys_seg: .word SYSSEG
+start_sys_seg: .word SYSSEG # obsolete and meaningless, but just
+ # in case something decided to "use" it
.word kernel_version-512 # pointing to kernel version string
# above section of header is compatible
# with loadlin-1.5 (header v1.5). Don't
# change it.
-type_of_loader: .byte 0 # = 0, old one (LILO, Loadlin,
- # Bootlin, SYSLX, bootsect...)
+type_of_loader: .byte 0 # 0 means ancient bootloader, newer
+ # bootloaders know to change this.
# See Documentation/i386/boot.txt for
# assigned ids
# space behind setup.S can be used for
# heap purposes.
# Only the loader knows what is free
-#ifndef __BIG_KERNEL__
- .byte 0
-#else
.byte LOADED_HIGH
-#endif
setup_move_size: .word 0x8000 # size to move, when setup is not
# loaded at 0x90000. We will move setup
code32_start: # here loaders can put a different
# start address for 32-bit code.
-#ifndef __BIG_KERNEL__
- .long 0x1000 # 0x1000 = default for zImage
-#else
.long 0x100000 # 0x100000 = default for big kernel
-#endif
ramdisk_image: .long 0 # address of loaded ramdisk image
# Here the loader puts the 32-bit
}
}
-/*
- * A zImage kernel is loaded at 0x10000 but wants to run at 0x1000.
- * A bzImage kernel is loaded and runs at 0x100000.
- */
-static void move_kernel_around(void)
-{
- /* Note: rely on the compile-time option here rather than
- the LOADED_HIGH flag. The Qemu kernel loader unconditionally
- sets the loadflags to zero. */
-#ifndef __BIG_KERNEL__
- u16 dst_seg, src_seg;
- u32 syssize;
-
- dst_seg = 0x1000 >> 4;
- src_seg = 0x10000 >> 4;
- syssize = boot_params.hdr.syssize; /* Size in 16-byte paragraphs */
-
- while (syssize) {
- int paras = (syssize >= 0x1000) ? 0x1000 : syssize;
- int dwords = paras << 2;
-
- asm volatile("pushw %%es ; "
- "pushw %%ds ; "
- "movw %1,%%es ; "
- "movw %2,%%ds ; "
- "xorw %%di,%%di ; "
- "xorw %%si,%%si ; "
- "rep;movsl ; "
- "popw %%ds ; "
- "popw %%es"
- : "+c" (dwords)
- : "r" (dst_seg), "r" (src_seg)
- : "esi", "edi");
-
- syssize -= paras;
- dst_seg += paras;
- src_seg += paras;
- }
-#endif
-}
-
/*
* Disable all interrupts at the legacy PIC.
*/
/* Hook before leaving real mode, also disables interrupts */
realmode_switch_hook();
- /* Move the kernel/setup to their final resting places */
- move_kernel_around();
-
/* Enable the A20 gate */
if (enable_a20()) {
puts("A20 gate not responding, unable to boot...\n");
static void usage(void)
{
- die("Usage: build [-b] setup system [rootdev] [> image]");
+ die("Usage: build setup system [rootdev] [> image]");
}
int main(int argc, char ** argv)
void *kernel;
u32 crc = 0xffffffffUL;
- if (argc > 2 && !strcmp(argv[1], "-b"))
- {
- is_big_kernel = 1;
- argc--, argv++;
- }
if ((argc < 3) || (argc > 4))
usage();
if (argc > 3) {
die("Unable to mmap '%s': %m", argv[2]);
/* Number of 16-byte paragraphs, including space for a 4-byte CRC */
sys_size = (sz + 15 + 4) / 16;
- if (!is_big_kernel && sys_size > DEF_SYSSIZE)
- die("System is too big. Try using bzImage or modules.");
/* Patch the setup code with the appropriate size parameters */
buf[0x1f1] = setup_sectors-1;
#ifndef _ASM_X86_BOOT_H
#define _ASM_X86_BOOT_H
-/* Don't touch these, unless you really know what you're doing. */
-#define DEF_SYSSEG 0x1000
-#define DEF_SYSSIZE 0x7F00
-
/* Internal svga startup constants */
#define NORMAL_VGA 0xffff /* 80x25 mode */
#define EXTENDED_VGA 0xfffe /* 80x50 mode */