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-rw-r--r--arch/x86/boot/Makefile5
-rw-r--r--arch/x86/boot/bioscall.S82
-rw-r--r--arch/x86/boot/boot.h48
-rw-r--r--arch/x86/boot/header.S2
-rw-r--r--arch/x86/boot/regs.c29
-rw-r--r--arch/x86/boot/setup.ld6
-rw-r--r--arch/x86/kernel/acpi/realmode/Makefile2
-rw-r--r--arch/x86/kernel/acpi/realmode/bioscall.S1
-rw-r--r--arch/x86/kernel/acpi/realmode/regs.c1
9 files changed, 172 insertions, 4 deletions
diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile
index 6633b6e7505a..658bc525cac7 100644
--- a/arch/x86/boot/Makefile
+++ b/arch/x86/boot/Makefile
@@ -26,9 +26,10 @@ targets := vmlinux.bin setup.bin setup.elf bzImage
targets += fdimage fdimage144 fdimage288 image.iso mtools.conf
subdir- := compressed
-setup-y += a20.o cmdline.o copy.o cpu.o cpucheck.o edd.o
+setup-y += a20.o bioscall.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 video-mode.o version.o
+setup-y += printf.o regs.o string.o tty.o video.o video-mode.o
+setup-y += version.o
setup-$(CONFIG_X86_APM_BOOT) += apm.o
# The link order of the video-*.o modules can matter. In particular,
diff --git a/arch/x86/boot/bioscall.S b/arch/x86/boot/bioscall.S
new file mode 100644
index 000000000000..22b4b3efb9f9
--- /dev/null
+++ b/arch/x86/boot/bioscall.S
@@ -0,0 +1,82 @@
+/* -----------------------------------------------------------------------
+ *
+ * Copyright 2009 Intel Corporation; author H. Peter Anvin
+ *
+ * This file is part of the Linux kernel, and is made available under
+ * the terms of the GNU General Public License version 2 or (at your
+ * option) any later version; incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * "Glove box" for BIOS calls. Avoids the constant problems with BIOSes
+ * touching memory they shouldn't be.
+ */
+
+ .code16
+ .text
+ .globl intcall
+ .type intcall, @function
+intcall:
+ /* Self-modify the INT instruction. Ugly, but works. */
+ cmpb %al, 3f
+ je 1f
+ movb %al, 3f
+ jmp 1f /* Synchronize pipeline */
+1:
+ /* Save state */
+ pushfl
+ pushw %fs
+ pushw %gs
+ pushal
+
+ /* Copy input state to stack frame */
+ subw $44, %sp
+ movw %dx, %si
+ movw %sp, %di
+ movw $11, %cx
+ rep; movsd
+
+ /* Pop full state from the stack */
+ popal
+ popw %gs
+ popw %fs
+ popw %es
+ popw %ds
+ popfl
+
+ /* Actual INT */
+ .byte 0xcd /* INT opcode */
+3: .byte 0
+
+ /* Push full state to the stack */
+ pushfl
+ pushw %ds
+ pushw %es
+ pushw %fs
+ pushw %gs
+ pushal
+
+ /* Re-establish C environment invariants */
+ cld
+ movzwl %sp, %esp
+ movw %cs, %ax
+ movw %ax, %ds
+ movw %ax, %es
+
+ /* Copy output state from stack frame */
+ movw 68(%esp), %di /* Original %cx == 3rd argument */
+ andw %di, %di
+ jz 4f
+ movw %sp, %si
+ movw $11, %cx
+ rep; movsd
+4: addw $44, %sp
+
+ /* Restore state and return */
+ popal
+ popw %gs
+ popw %fs
+ popfl
+ retl
+ .size intcall, .-intcall
diff --git a/arch/x86/boot/boot.h b/arch/x86/boot/boot.h
index 7b2692e897e5..98239d2658f2 100644
--- a/arch/x86/boot/boot.h
+++ b/arch/x86/boot/boot.h
@@ -2,6 +2,7 @@
*
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright 2007 rPath, Inc. - All Rights Reserved
+ * Copyright 2009 Intel Corporation; author H. Peter Anvin
*
* This file is part of the Linux kernel, and is made available under
* the terms of the GNU General Public License version 2.
@@ -26,6 +27,7 @@
#include <asm/setup.h>
#include "bitops.h"
#include <asm/cpufeature.h>
+#include <asm/processor-flags.h>
/* Useful macros */
#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
@@ -241,6 +243,49 @@ int enable_a20(void);
/* apm.c */
int query_apm_bios(void);
+/* bioscall.c */
+struct biosregs {
+ union {
+ struct {
+ u32 edi;
+ u32 esi;
+ u32 ebp;
+ u32 _esp;
+ u32 ebx;
+ u32 edx;
+ u32 ecx;
+ u32 eax;
+ u32 _fsgs;
+ u32 _dses;
+ u32 eflags;
+ };
+ struct {
+ u16 di, hdi;
+ u16 si, hsi;
+ u16 bp, hbp;
+ u16 _sp, _hsp;
+ u16 bx, hbx;
+ u16 dx, hdx;
+ u16 cx, hcx;
+ u16 ax, hax;
+ u16 gs, fs;
+ u16 es, ds;
+ u16 flags, hflags;
+ };
+ struct {
+ u8 dil, dih, edi2, edi3;
+ u8 sil, sih, esi2, esi3;
+ u8 bpl, bph, ebp2, ebp3;
+ u8 _spl, _sph, _esp2, _esp3;
+ u8 bl, bh, ebx2, ebx3;
+ u8 dl, dh, edx2, edx3;
+ u8 cl, ch, ecx2, ecx3;
+ u8 al, ah, eax2, eax3;
+ };
+ };
+};
+void intcall(u8 int_no, const struct biosregs *ireg, struct biosregs *oreg);
+
/* cmdline.c */
int cmdline_find_option(const char *option, char *buffer, int bufsize);
int cmdline_find_option_bool(const char *option);
@@ -279,6 +324,9 @@ int sprintf(char *buf, const char *fmt, ...);
int vsprintf(char *buf, const char *fmt, va_list args);
int printf(const char *fmt, ...);
+/* regs.c */
+void initregs(struct biosregs *regs);
+
/* string.c */
int strcmp(const char *str1, const char *str2);
size_t strnlen(const char *s, size_t maxlen);
diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S
index 5d84d1c74e4c..486d97fa7f4d 100644
--- a/arch/x86/boot/header.S
+++ b/arch/x86/boot/header.S
@@ -221,7 +221,7 @@ setup_data: .quad 0 # 64-bit physical pointer to
# End of setup header #####################################################
- .section ".inittext", "ax"
+ .section ".entrytext", "ax"
start_of_setup:
#ifdef SAFE_RESET_DISK_CONTROLLER
# Reset the disk controller.
diff --git a/arch/x86/boot/regs.c b/arch/x86/boot/regs.c
new file mode 100644
index 000000000000..958019b1cfa5
--- /dev/null
+++ b/arch/x86/boot/regs.c
@@ -0,0 +1,29 @@
+/* -----------------------------------------------------------------------
+ *
+ * Copyright 2009 Intel Corporation; author H. Peter Anvin
+ *
+ * This file is part of the Linux kernel, and is made available under
+ * the terms of the GNU General Public License version 2 or (at your
+ * option) any later version; incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * Simple helper function for initializing a register set.
+ *
+ * Note that this sets EFLAGS_CF in the input register set; this
+ * makes it easier to catch functions which do nothing but don't
+ * explicitly set CF.
+ */
+
+#include "boot.h"
+
+void initregs(struct biosregs *reg)
+{
+ memset(reg, 0, sizeof *reg);
+ reg->eflags |= X86_EFLAGS_CF;
+ reg->ds = ds();
+ reg->es = ds();
+ reg->fs = fs();
+ reg->gs = gs();
+}
diff --git a/arch/x86/boot/setup.ld b/arch/x86/boot/setup.ld
index bb8dc2de7969..0f6ec455a2b1 100644
--- a/arch/x86/boot/setup.ld
+++ b/arch/x86/boot/setup.ld
@@ -15,8 +15,11 @@ SECTIONS
. = 497;
.header : { *(.header) }
+ .entrytext : { *(.entrytext) }
.inittext : { *(.inittext) }
.initdata : { *(.initdata) }
+ __end_init = .;
+
.text : { *(.text) }
.text32 : { *(.text32) }
@@ -52,4 +55,7 @@ SECTIONS
. = ASSERT(_end <= 0x8000, "Setup too big!");
. = ASSERT(hdr == 0x1f1, "The setup header has the wrong offset!");
+ /* Necessary for the very-old-loader check to work... */
+ . = ASSERT(__end_init <= 5*512, "init sections too big!");
+
}
diff --git a/arch/x86/kernel/acpi/realmode/Makefile b/arch/x86/kernel/acpi/realmode/Makefile
index 1c31cc0e9def..167bc16ce0e5 100644
--- a/arch/x86/kernel/acpi/realmode/Makefile
+++ b/arch/x86/kernel/acpi/realmode/Makefile
@@ -9,7 +9,7 @@
always := wakeup.bin
targets := wakeup.elf wakeup.lds
-wakeup-y += wakeup.o wakemain.o video-mode.o copy.o
+wakeup-y += wakeup.o wakemain.o video-mode.o copy.o bioscall.o regs.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.
diff --git a/arch/x86/kernel/acpi/realmode/bioscall.S b/arch/x86/kernel/acpi/realmode/bioscall.S
new file mode 100644
index 000000000000..f51eb0bb56ce
--- /dev/null
+++ b/arch/x86/kernel/acpi/realmode/bioscall.S
@@ -0,0 +1 @@
+#include "../../../boot/bioscall.S"
diff --git a/arch/x86/kernel/acpi/realmode/regs.c b/arch/x86/kernel/acpi/realmode/regs.c
new file mode 100644
index 000000000000..6206033ba202
--- /dev/null
+++ b/arch/x86/kernel/acpi/realmode/regs.c
@@ -0,0 +1 @@
+#include "../../../boot/regs.c"