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Use the new x86 setup code for i386
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This patch hooks the new x86 setup code into the Makefile machinery.  It
also adapts boot/tools/build.c to a two-file (as opposed to three-file)
universe, and simplifies it substantially.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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H. Peter Anvin authored and Linus Torvalds committed Jul 12, 2007
1 parent f2d98ae commit 4fd0696
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Showing 3 changed files with 118 additions and 97 deletions.
48 changes: 41 additions & 7 deletions arch/i386/boot/Makefile
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Original file line number Diff line number Diff line change
Expand Up @@ -25,40 +25,74 @@ SVGA_MODE := -DSVGA_MODE=NORMAL_VGA

#RAMDISK := -DRAMDISK=512

targets := vmlinux.bin bootsect bootsect.o \
setup setup.o zImage bzImage
targets := vmlinux.bin setup.bin setup.elf zImage bzImage
subdir- := compressed

setup-y += a20.o apm.o cmdline.o copy.o cpu.o cpucheck.o edd.o
setup-y += header.o main.o mca.o memory.o pm.o pmjump.o
setup-y += printf.o string.o tty.o video.o version.o voyager.o

# The link order of the video-*.o modules can matter. In particular,
# video-vga.o *must* be listed first, followed by video-vesa.o.
# Hardware-specific drivers should follow in the order they should be
# probed, and video-bios.o should typically be last.
setup-y += video-vga.o
setup-y += video-vesa.o
setup-y += video-bios.o

hostprogs-y := tools/build

HOSTCFLAGS_build.o := $(LINUXINCLUDE)

# ---------------------------------------------------------------------------

# How to compile the 16-bit code. Note we always compile for -march=i386,
# that way we can complain to the user if the CPU is insufficient.
cflags-i386 :=
cflags-x86_64 := -m32
CFLAGS := $(LINUXINCLUDE) -g -Os -D_SETUP -D__KERNEL__ \
$(cflags-$(ARCH)) \
-Wall -Wstrict-prototypes \
-march=i386 -mregparm=3 \
-include $(srctree)/$(src)/code16gcc.h \
-fno-strict-aliasing -fomit-frame-pointer \
$(call cc-option, -ffreestanding) \
$(call cc-option, -fno-toplevel-reorder,\
$(call cc-option, -fno-unit-at-a-time)) \
$(call cc-option, -fno-stack-protector) \
$(call cc-option, -mpreferred-stack-boundary=2)
AFLAGS := $(CFLAGS) -D__ASSEMBLY__

$(obj)/zImage: IMAGE_OFFSET := 0x1000
$(obj)/zImage: EXTRA_AFLAGS := $(SVGA_MODE) $(RAMDISK)
$(obj)/bzImage: IMAGE_OFFSET := 0x100000
$(obj)/bzImage: EXTRA_CFLAGS := -D__BIG_KERNEL__
$(obj)/bzImage: EXTRA_AFLAGS := $(SVGA_MODE) $(RAMDISK) -D__BIG_KERNEL__
$(obj)/bzImage: BUILDFLAGS := -b

quiet_cmd_image = BUILD $@
cmd_image = $(obj)/tools/build $(BUILDFLAGS) $(obj)/bootsect $(obj)/setup \
cmd_image = $(obj)/tools/build $(BUILDFLAGS) $(obj)/setup.bin \
$(obj)/vmlinux.bin $(ROOT_DEV) > $@

$(obj)/zImage $(obj)/bzImage: $(obj)/bootsect $(obj)/setup \
$(obj)/zImage $(obj)/bzImage: $(obj)/setup.bin \
$(obj)/vmlinux.bin $(obj)/tools/build FORCE
$(call if_changed,image)
@echo 'Kernel: $@ is ready' ' (#'`cat .version`')'

$(obj)/vmlinux.bin: $(obj)/compressed/vmlinux FORCE
$(call if_changed,objcopy)

LDFLAGS_bootsect := -Ttext 0x0 -s --oformat binary
LDFLAGS_setup := -Ttext 0x0 -s --oformat binary -e begtext
SETUP_OBJS = $(addprefix $(obj)/,$(setup-y))

$(obj)/setup $(obj)/bootsect: %: %.o FORCE
LDFLAGS_setup.elf := -T
$(obj)/setup.elf: $(src)/setup.ld $(SETUP_OBJS) FORCE
$(call if_changed,ld)

OBJCOPYFLAGS_setup.bin := -O binary

$(obj)/setup.bin: $(obj)/setup.elf FORCE
$(call if_changed,objcopy)

$(obj)/compressed/vmlinux: FORCE
$(Q)$(MAKE) $(build)=$(obj)/compressed IMAGE_OFFSET=$(IMAGE_OFFSET) $@

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7 changes: 6 additions & 1 deletion arch/i386/boot/compressed/Makefile
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Original file line number Diff line number Diff line change
Expand Up @@ -9,9 +9,14 @@ targets := vmlinux vmlinux.bin vmlinux.bin.gz head.o misc.o piggy.o \
EXTRA_AFLAGS := -traditional

LDFLAGS_vmlinux := -T
CFLAGS_misc.o += -fPIC
hostprogs-y := relocs

CFLAGS := -m32 -D__KERNEL__ $(LINUX_INCLUDE) -O2 \
-fno-strict-aliasing -fPIC \
$(call cc-option,-ffreestanding) \
$(call cc-option,-fno-stack-protector)
LDFLAGS := -m elf_i386

$(obj)/vmlinux: $(src)/vmlinux.lds $(obj)/head.o $(obj)/misc.o $(obj)/piggy.o FORCE
$(call if_changed,ld)
@:
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160 changes: 71 additions & 89 deletions arch/i386/boot/tools/build.c
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Original file line number Diff line number Diff line change
@@ -1,13 +1,12 @@
/*
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright (C) 1997 Martin Mares
* Copyright (C) 2007 H. Peter Anvin
*/

/*
* This file builds a disk-image from three different files:
*
* - bootsect: compatibility mbr which prints an error message if
* someone tries to boot the kernel directly.
* - setup: 8086 machine code, sets up system parm
* - system: 80386 code for actual system
*
Expand All @@ -21,6 +20,7 @@
* High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
* Cross compiling fixes by Gertjan van Wingerde, July 1996
* Rewritten by Martin Mares, April 1997
* Substantially overhauled by H. Peter Anvin, April 2007
*/

#include <stdio.h>
Expand All @@ -32,23 +32,25 @@
#include <sys/sysmacros.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <asm/boot.h>

typedef unsigned char byte;
typedef unsigned short word;
typedef unsigned long u32;
typedef unsigned char u8;
typedef unsigned short u16;
typedef unsigned long u32;

#define DEFAULT_MAJOR_ROOT 0
#define DEFAULT_MINOR_ROOT 0

/* Minimal number of setup sectors (see also bootsect.S) */
#define SETUP_SECTS 4
/* Minimal number of setup sectors */
#define SETUP_SECT_MIN 5
#define SETUP_SECT_MAX 64

byte buf[1024];
int fd;
/* This must be large enough to hold the entire setup */
u8 buf[SETUP_SECT_MAX*512];
int is_big_kernel;

void die(const char * str, ...)
static void die(const char * str, ...)
{
va_list args;
va_start(args, str);
Expand All @@ -57,43 +59,40 @@ void die(const char * str, ...)
exit(1);
}

void file_open(const char *name)
static void usage(void)
{
if ((fd = open(name, O_RDONLY, 0)) < 0)
die("Unable to open `%s': %m", name);
}

void usage(void)
{
die("Usage: build [-b] bootsect setup system [rootdev] [> image]");
die("Usage: build [-b] setup system [rootdev] [> image]");
}

int main(int argc, char ** argv)
{
unsigned int i, sz, setup_sectors;
int c;
u32 sys_size;
byte major_root, minor_root;
u8 major_root, minor_root;
struct stat sb;
FILE *file;
int fd;
void *kernel;

if (argc > 2 && !strcmp(argv[1], "-b"))
{
is_big_kernel = 1;
argc--, argv++;
}
if ((argc < 4) || (argc > 5))
if ((argc < 3) || (argc > 4))
usage();
if (argc > 4) {
if (!strcmp(argv[4], "CURRENT")) {
if (argc > 3) {
if (!strcmp(argv[3], "CURRENT")) {
if (stat("/", &sb)) {
perror("/");
die("Couldn't stat /");
}
major_root = major(sb.st_dev);
minor_root = minor(sb.st_dev);
} else if (strcmp(argv[4], "FLOPPY")) {
if (stat(argv[4], &sb)) {
perror(argv[4]);
} else if (strcmp(argv[3], "FLOPPY")) {
if (stat(argv[3], &sb)) {
perror(argv[3]);
die("Couldn't stat root device.");
}
major_root = major(sb.st_rdev);
Expand All @@ -108,79 +107,62 @@ int main(int argc, char ** argv)
}
fprintf(stderr, "Root device is (%d, %d)\n", major_root, minor_root);

file_open(argv[1]);
i = read(fd, buf, sizeof(buf));
fprintf(stderr,"Boot sector %d bytes.\n",i);
if (i != 512)
die("Boot block must be exactly 512 bytes");
/* Copy the setup code */
file = fopen(argv[1], "r");
if (!file)
die("Unable to open `%s': %m", argv[1]);
c = fread(buf, 1, sizeof(buf), file);
if (ferror(file))
die("read-error on `setup'");
if (c < 1024)
die("The setup must be at least 1024 bytes");
if (buf[510] != 0x55 || buf[511] != 0xaa)
die("Boot block hasn't got boot flag (0xAA55)");
fclose(file);

/* Pad unused space with zeros */
setup_sectors = (c + 511) / 512;
if (setup_sectors < SETUP_SECT_MIN)
setup_sectors = SETUP_SECT_MIN;
i = setup_sectors*512;
memset(buf+c, 0, i-c);

/* Set the default root device */
buf[508] = minor_root;
buf[509] = major_root;
if (write(1, buf, 512) != 512)
die("Write call failed");
close (fd);

file_open(argv[2]); /* Copy the setup code */
for (i=0 ; (c=read(fd, buf, sizeof(buf)))>0 ; i+=c )
if (write(1, buf, c) != c)
die("Write call failed");
if (c != 0)
die("read-error on `setup'");
close (fd);

setup_sectors = (i + 511) / 512; /* Pad unused space with zeros */
/* for compatibility with ancient versions of LILO. */
if (setup_sectors < SETUP_SECTS)
setup_sectors = SETUP_SECTS;
fprintf(stderr, "Setup is %d bytes.\n", i);
memset(buf, 0, sizeof(buf));
while (i < setup_sectors * 512) {
c = setup_sectors * 512 - i;
if (c > sizeof(buf))
c = sizeof(buf);
if (write(1, buf, c) != c)
die("Write call failed");
i += c;
}

file_open(argv[3]);
if (fstat (fd, &sb))
die("Unable to stat `%s': %m", argv[3]);
fprintf(stderr, "Setup is %d bytes (padded to %d bytes).\n", c, i);

/* Open and stat the kernel file */
fd = open(argv[2], O_RDONLY);
if (fd < 0)
die("Unable to open `%s': %m", argv[2]);
if (fstat(fd, &sb))
die("Unable to stat `%s': %m", argv[2]);
sz = sb.st_size;
fprintf (stderr, "System is %d kB\n", sz/1024);
fprintf (stderr, "System is %d kB\n", (sz+1023)/1024);
kernel = mmap(NULL, sz, PROT_READ, MAP_SHARED, fd, 0);
if (kernel == MAP_FAILED)
die("Unable to mmap '%s': %m", argv[2]);
sys_size = (sz + 15) / 16;
if (!is_big_kernel && sys_size > DEF_SYSSIZE)
die("System is too big. Try using bzImage or modules.");
while (sz > 0) {
int l, n;

l = (sz > sizeof(buf)) ? sizeof(buf) : sz;
if ((n=read(fd, buf, l)) != l) {
if (n < 0)
die("Error reading %s: %m", argv[3]);
else
die("%s: Unexpected EOF", argv[3]);
}
if (write(1, buf, l) != l)
die("Write failed");
sz -= l;
}

/* Patch the setup code with the appropriate size parameters */
buf[0x1f1] = setup_sectors-1;
buf[0x1f4] = sys_size;
buf[0x1f5] = sys_size >> 8;
buf[0x1f6] = sys_size >> 16;
buf[0x1f7] = sys_size >> 24;

if (fwrite(buf, 1, i, stdout) != i)
die("Writing setup failed");

/* Copy the kernel code */
if (fwrite(kernel, 1, sz, stdout) != sz)
die("Writing kernel failed");
close(fd);

if (lseek(1, 497, SEEK_SET) != 497) /* Write sizes to the bootsector */
die("Output: seek failed");
buf[0] = setup_sectors;
if (write(1, buf, 1) != 1)
die("Write of setup sector count failed");
if (lseek(1, 500, SEEK_SET) != 500)
die("Output: seek failed");
buf[0] = (sys_size & 0xff);
buf[1] = ((sys_size >> 8) & 0xff);
buf[2] = ((sys_size >> 16) & 0xff);
buf[3] = ((sys_size >> 24) & 0xff);
if (write(1, buf, 4) != 4)
die("Write of image length failed");

return 0; /* Everything is OK */
/* Everything is OK */
return 0;
}

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