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diff --git a/Documentation/i386/IO-APIC.txt b/Documentation/i386/IO-APIC.txt
new file mode 100644
index 000000000000..435e69e6e9aa
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+++ b/Documentation/i386/IO-APIC.txt
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+Most (all) Intel-MP compliant SMP boards have the so-called 'IO-APIC',
+which is an enhanced interrupt controller, it enables us to route
+hardware interrupts to multiple CPUs, or to CPU groups.
+
+Linux supports all variants of compliant SMP boards, including ones with
+multiple IO-APICs. (multiple IO-APICs are used in high-end servers to
+distribute IRQ load further).
+
+There are (a few) known breakages in certain older boards, which bugs are
+usually worked around by the kernel. If your MP-compliant SMP board does
+not boot Linux, then consult the linux-smp mailing list archives first.
+
+If your box boots fine with enabled IO-APIC IRQs, then your
+/proc/interrupts will look like this one:
+
+   ---------------------------->
+  hell:~> cat /proc/interrupts
+             CPU0
+    0:    1360293    IO-APIC-edge  timer
+    1:          4    IO-APIC-edge  keyboard
+    2:          0          XT-PIC  cascade
+   13:          1          XT-PIC  fpu
+   14:       1448    IO-APIC-edge  ide0
+   16:      28232   IO-APIC-level  Intel EtherExpress Pro 10/100 Ethernet
+   17:      51304   IO-APIC-level  eth0
+  NMI:          0
+  ERR:          0
+  hell:~>
+  <----------------------------
+
+some interrupts are still listed as 'XT PIC', but this is not a problem,
+none of those IRQ sources is performance-critical.
+
+
+in the unlikely case that your board does not create a working mp-table,
+you can use the pirq= boot parameter to 'hand-construct' IRQ entries. This
+is nontrivial though and cannot be automated. One sample /etc/lilo.conf
+entry:
+
+        append="pirq=15,11,10"
+
+the actual numbers depend on your system, on your PCI cards and on their
+PCI slot position. Usually PCI slots are 'daisy chained' before they are
+connected to the PCI chipset IRQ routing facility (the incoming PIRQ1-4
+lines):
+
+               ,-.        ,-.        ,-.        ,-.        ,-.
+     PIRQ4 ----| |-.    ,-| |-.    ,-| |-.    ,-| |--------| |
+               |S|  \  /  |S|  \  /  |S|  \  /  |S|        |S|
+     PIRQ3 ----|l|-. `/---|l|-. `/---|l|-. `/---|l|--------|l|
+               |o|  \/    |o|  \/    |o|  \/    |o|        |o|
+     PIRQ2 ----|t|-./`----|t|-./`----|t|-./`----|t|--------|t|
+               |1| /\     |2| /\     |3| /\     |4|        |5|
+     PIRQ1 ----| |-  `----| |-  `----| |-  `----| |--------| |
+               `-'        `-'        `-'        `-'        `-'
+
+every PCI card emits a PCI IRQ, which can be INTA,INTB,INTC,INTD:
+
+                               ,-.
+                         INTD--| |
+                               |S|
+                         INTC--|l|
+                               |o|
+                         INTB--|t|
+                               |x|
+                         INTA--| |
+                               `-'
+
+These INTA-D PCI IRQs are always 'local to the card', their real meaning
+depends on which slot they are in. If you look at the daisy chaining diagram,
+a card in slot4, issuing INTA IRQ, it will end up as a signal on PIRQ2 of
+the PCI chipset. Most cards issue INTA, this creates optimal distribution
+between the PIRQ lines. (distributing IRQ sources properly is not a
+necessity, PCI IRQs can be shared at will, but it's a good for performance
+to have non shared interrupts). Slot5 should be used for videocards, they
+do not use interrupts normally, thus they are not daisy chained either.
+
+so if you have your SCSI card (IRQ11) in Slot1, Tulip card (IRQ9) in
+Slot2, then you'll have to specify this pirq= line:
+
+        append="pirq=11,9"
+
+the following script tries to figure out such a default pirq= line from
+your PCI configuration:
+
+        echo -n pirq=; echo `scanpci | grep T_L | cut -c56-` | sed 's/ /,/g'
+
+note that this script wont work if you have skipped a few slots or if your
+board does not do default daisy-chaining. (or the IO-APIC has the PIRQ pins
+connected in some strange way). E.g. if in the above case you have your SCSI
+card (IRQ11) in Slot3, and have Slot1 empty:
+
+        append="pirq=0,9,11"
+
+[value '0' is a generic 'placeholder', reserved for empty (or non-IRQ emitting)
+slots.]
+
+generally, it's always possible to find out the correct pirq= settings, just
+permute all IRQ numbers properly ... it will take some time though. An
+'incorrect' pirq line will cause the booting process to hang, or a device
+won't function properly (if it's inserted as eg. a module).
+
+If you have 2 PCI buses, then you can use up to 8 pirq values. Although such
+boards tend to have a good configuration.
+
+Be prepared that it might happen that you need some strange pirq line:
+
+        append="pirq=0,0,0,0,0,0,9,11"
+
+use smart try-and-err techniques to find out the correct pirq line ...
+
+good luck and mail to linux-smp@vger.kernel.org or
+linux-kernel@vger.kernel.org if you have any problems that are not covered
+by this document.
+
+-- mingo
+
diff --git a/Documentation/i386/boot.txt b/Documentation/i386/boot.txt
new file mode 100644
index 000000000000..1c48f0eba6fb
--- /dev/null
+++ b/Documentation/i386/boot.txt
@@ -0,0 +1,441 @@
+                     THE LINUX/I386 BOOT PROTOCOL
+                     ----------------------------
+
+                    H. Peter Anvin <hpa@zytor.com>
+                        Last update 2002-01-01
+
+On the i386 platform, the Linux kernel uses a rather complicated boot
+convention.  This has evolved partially due to historical aspects, as
+well as the desire in the early days to have the kernel itself be a
+bootable image, the complicated PC memory model and due to changed
+expectations in the PC industry caused by the effective demise of
+real-mode DOS as a mainstream operating system.
+
+Currently, four versions of the Linux/i386 boot protocol exist.
+
+Old kernels:    zImage/Image support only.  Some very early kernels
+                may not even support a command line.
+
+Protocol 2.00:  (Kernel 1.3.73) Added bzImage and initrd support, as
+                well as a formalized way to communicate between the
+                boot loader and the kernel.  setup.S made relocatable,
+                although the traditional setup area still assumed
+                writable.
+
+Protocol 2.01:  (Kernel 1.3.76) Added a heap overrun warning.
+
+Protocol 2.02:  (Kernel 2.4.0-test3-pre3) New command line protocol.
+                Lower the conventional memory ceiling.  No overwrite
+                of the traditional setup area, thus making booting
+                safe for systems which use the EBDA from SMM or 32-bit
+                BIOS entry points.  zImage deprecated but still
+                supported.
+
+Protocol 2.03:  (Kernel 2.4.18-pre1) Explicitly makes the highest possible
+                initrd address available to the bootloader.
+
+
+**** MEMORY LAYOUT
+
+The traditional memory map for the kernel loader, used for Image or
+zImage kernels, typically looks like:
+
+        |                        |
+0A0000  +------------------------+
+        |  Reserved for BIOS     |      Do not use.  Reserved for BIOS EBDA.
+09A000  +------------------------+
+        |  Stack/heap/cmdline    |      For use by the kernel real-mode code.
+098000  +------------------------+      
+        |  Kernel setup          |      The kernel real-mode code.
+090200  +------------------------+
+        |  Kernel boot sector    |      The kernel legacy boot sector.
+090000  +------------------------+
+        |  Protected-mode kernel |      The bulk of the kernel image.
+010000  +------------------------+
+        |  Boot loader           |      <- Boot sector entry point 0000:7C00
+001000  +------------------------+
+        |  Reserved for MBR/BIOS |
+000800  +------------------------+
+        |  Typically used by MBR |
+000600  +------------------------+ 
+        |  BIOS use only         |
+000000  +------------------------+
+
+
+When using bzImage, the protected-mode kernel was relocated to
+0x100000 ("high memory"), and the kernel real-mode block (boot sector,
+setup, and stack/heap) was made relocatable to any address between
+0x10000 and end of low memory.  Unfortunately, in protocols 2.00 and
+2.01 the command line is still required to live in the 0x9XXXX memory
+range, and that memory range is still overwritten by the early kernel.
+The 2.02 protocol resolves that problem.
+
+It is desirable to keep the "memory ceiling" -- the highest point in
+low memory touched by the boot loader -- as low as possible, since
+some newer BIOSes have begun to allocate some rather large amounts of
+memory, called the Extended BIOS Data Area, near the top of low
+memory.  The boot loader should use the "INT 12h" BIOS call to verify
+how much low memory is available.
+
+Unfortunately, if INT 12h reports that the amount of memory is too
+low, there is usually nothing the boot loader can do but to report an
+error to the user.  The boot loader should therefore be designed to
+take up as little space in low memory as it reasonably can.  For
+zImage or old bzImage kernels, which need data written into the
+0x90000 segment, the boot loader should make sure not to use memory
+above the 0x9A000 point; too many BIOSes will break above that point.
+
+
+**** THE REAL-MODE KERNEL HEADER
+
+In the following text, and anywhere in the kernel boot sequence, "a
+sector" refers to 512 bytes.  It is independent of the actual sector
+size of the underlying medium.
+
+The first step in loading a Linux kernel should be to load the
+real-mode code (boot sector and setup code) and then examine the
+following header at offset 0x01f1.  The real-mode code can total up to
+32K, although the boot loader may choose to load only the first two
+sectors (1K) and then examine the bootup sector size.
+
+The header looks like:
+
+Offset  Proto   Name            Meaning
+/Size
+
+01F1/1  ALL     setup_sects     The size of the setup in sectors
+01F2/2  ALL     root_flags      If set, the root is mounted readonly
+01F4/2  ALL     syssize         DO NOT USE - for bootsect.S use only
+01F6/2  ALL     swap_dev        DO NOT USE - obsolete
+01F8/2  ALL     ram_size        DO NOT USE - for bootsect.S use only
+01FA/2  ALL     vid_mode        Video mode control
+01FC/2  ALL     root_dev        Default root device number
+01FE/2  ALL     boot_flag       0xAA55 magic number
+0200/2  2.00+   jump            Jump instruction
+0202/4  2.00+   header          Magic signature "HdrS"
+0206/2  2.00+   version         Boot protocol version supported
+0208/4  2.00+   realmode_swtch  Boot loader hook (see below)
+020C/2  2.00+   start_sys       The load-low segment (0x1000) (obsolete)
+020E/2  2.00+   kernel_version  Pointer to kernel version string
+0210/1  2.00+   type_of_loader  Boot loader identifier
+0211/1  2.00+   loadflags       Boot protocol option flags
+0212/2  2.00+   setup_move_size Move to high memory size (used with hooks)
+0214/4  2.00+   code32_start    Boot loader hook (see below)
+0218/4  2.00+   ramdisk_image   initrd load address (set by boot loader)
+021C/4  2.00+   ramdisk_size    initrd size (set by boot loader)
+0220/4  2.00+   bootsect_kludge DO NOT USE - for bootsect.S use only
+0224/2  2.01+   heap_end_ptr    Free memory after setup end
+0226/2  N/A     pad1            Unused
+0228/4  2.02+   cmd_line_ptr    32-bit pointer to the kernel command line
+022C/4  2.03+   initrd_addr_max Highest legal initrd address
+
+For backwards compatibility, if the setup_sects field contains 0, the
+real value is 4.
+
+If the "HdrS" (0x53726448) magic number is not found at offset 0x202,
+the boot protocol version is "old".  Loading an old kernel, the
+following parameters should be assumed:
+
+        Image type = zImage
+        initrd not supported
+        Real-mode kernel must be located at 0x90000.
+
+Otherwise, the "version" field contains the protocol version,
+e.g. protocol version 2.01 will contain 0x0201 in this field.  When
+setting fields in the header, you must make sure only to set fields
+supported by the protocol version in use.
+
+The "kernel_version" field, if set to a nonzero value, contains a
+pointer to a null-terminated human-readable kernel version number
+string, less 0x200.  This can be used to display the kernel version to
+the user.  This value should be less than (0x200*setup_sects).  For
+example, if this value is set to 0x1c00, the kernel version number
+string can be found at offset 0x1e00 in the kernel file.  This is a
+valid value if and only if the "setup_sects" field contains the value
+14 or higher.
+
+Most boot loaders will simply load the kernel at its target address
+directly.  Such boot loaders do not need to worry about filling in
+most of the fields in the header.  The following fields should be
+filled out, however:
+
+  vid_mode:
+        Please see the section on SPECIAL COMMAND LINE OPTIONS.
+
+  type_of_loader:
+        If your boot loader has an assigned id (see table below), enter
+        0xTV here, where T is an identifier for the boot loader and V is
+        a version number.  Otherwise, enter 0xFF here.
+
+        Assigned boot loader ids:
+        0  LILO
+        1  Loadlin
+        2  bootsect-loader
+        3  SYSLINUX
+        4  EtherBoot
+        5  ELILO
+        7  GRuB
+        8  U-BOOT
+
+        Please contact <hpa@zytor.com> if you need a bootloader ID
+        value assigned.
+
+  loadflags, heap_end_ptr:
+        If the protocol version is 2.01 or higher, enter the
+        offset limit of the setup heap into heap_end_ptr and set the
+        0x80 bit (CAN_USE_HEAP) of loadflags.  heap_end_ptr appears to
+        be relative to the start of setup (offset 0x0200).
+
+  setup_move_size: 
+        When using protocol 2.00 or 2.01, if the real mode
+        kernel is not loaded at 0x90000, it gets moved there later in
+        the loading sequence.  Fill in this field if you want
+        additional data (such as the kernel command line) moved in
+        addition to the real-mode kernel itself.
+
+  ramdisk_image, ramdisk_size:
+        If your boot loader has loaded an initial ramdisk (initrd),
+        set ramdisk_image to the 32-bit pointer to the ramdisk data
+        and the ramdisk_size to the size of the ramdisk data.
+
+        The initrd should typically be located as high in memory as
+        possible, as it may otherwise get overwritten by the early
+        kernel initialization sequence.  However, it must never be
+        located above the address specified in the initrd_addr_max
+        field.  The initrd should be at least 4K page aligned.
+
+  cmd_line_ptr:
+        If the protocol version is 2.02 or higher, this is a 32-bit
+        pointer to the kernel command line.  The kernel command line
+        can be located anywhere between the end of setup and 0xA0000.
+        Fill in this field even if your boot loader does not support a
+        command line, in which case you can point this to an empty
+        string (or better yet, to the string "auto".)  If this field
+        is left at zero, the kernel will assume that your boot loader
+        does not support the 2.02+ protocol.
+
+  ramdisk_max:
+        The maximum address that may be occupied by the initrd
+        contents.  For boot protocols 2.02 or earlier, this field is
+        not present, and the maximum address is 0x37FFFFFF.  (This
+        address is defined as the address of the highest safe byte, so
+        if your ramdisk is exactly 131072 bytes long and this field is
+        0x37FFFFFF, you can start your ramdisk at 0x37FE0000.)
+
+
+**** THE KERNEL COMMAND LINE
+
+The kernel command line has become an important way for the boot
+loader to communicate with the kernel.  Some of its options are also
+relevant to the boot loader itself, see "special command line options"
+below.
+
+The kernel command line is a null-terminated string up to 255
+characters long, plus the final null.
+
+If the boot protocol version is 2.02 or later, the address of the
+kernel command line is given by the header field cmd_line_ptr (see
+above.)
+
+If the protocol version is *not* 2.02 or higher, the kernel
+command line is entered using the following protocol:
+
+        At offset 0x0020 (word), "cmd_line_magic", enter the magic
+        number 0xA33F.
+
+        At offset 0x0022 (word), "cmd_line_offset", enter the offset
+        of the kernel command line (relative to the start of the
+        real-mode kernel).
+        
+        The kernel command line *must* be within the memory region
+        covered by setup_move_size, so you may need to adjust this
+        field.
+
+
+**** SAMPLE BOOT CONFIGURATION
+
+As a sample configuration, assume the following layout of the real
+mode segment:
+
+        0x0000-0x7FFF   Real mode kernel
+        0x8000-0x8FFF   Stack and heap
+        0x9000-0x90FF   Kernel command line
+
+Such a boot loader should enter the following fields in the header:
+
+        unsigned long base_ptr; /* base address for real-mode segment */
+
+        if ( setup_sects == 0 ) {
+                setup_sects = 4;
+        }
+
+        if ( protocol >= 0x0200 ) {
+                type_of_loader = <type code>;
+                if ( loading_initrd ) {
+                        ramdisk_image = <initrd_address>;
+                        ramdisk_size = <initrd_size>;
+                }
+                if ( protocol >= 0x0201 ) {
+                        heap_end_ptr = 0x9000 - 0x200;
+                        loadflags |= 0x80; /* CAN_USE_HEAP */
+                }
+                if ( protocol >= 0x0202 ) {
+                        cmd_line_ptr = base_ptr + 0x9000;
+                } else {
+                        cmd_line_magic  = 0xA33F;
+                        cmd_line_offset = 0x9000;
+                        setup_move_size = 0x9100;
+                }
+        } else {
+                /* Very old kernel */
+
+                cmd_line_magic  = 0xA33F;
+                cmd_line_offset = 0x9000;
+
+                /* A very old kernel MUST have its real-mode code
+                   loaded at 0x90000 */
+
+                if ( base_ptr != 0x90000 ) {
+                        /* Copy the real-mode kernel */
+                        memcpy(0x90000, base_ptr, (setup_sects+1)*512);
+                        /* Copy the command line */
+                        memcpy(0x99000, base_ptr+0x9000, 256);
+
+                        base_ptr = 0x90000;              /* Relocated */
+                }
+
+                /* It is recommended to clear memory up to the 32K mark */
+                memset(0x90000 + (setup_sects+1)*512, 0,
+                       (64-(setup_sects+1))*512);
+        }
+
+
+**** LOADING THE REST OF THE KERNEL
+
+The non-real-mode kernel starts at offset (setup_sects+1)*512 in the
+kernel file (again, if setup_sects == 0 the real value is 4.)  It
+should be loaded at address 0x10000 for Image/zImage kernels and
+0x100000 for bzImage kernels.
+
+The kernel is a bzImage kernel if the protocol >= 2.00 and the 0x01
+bit (LOAD_HIGH) in the loadflags field is set:
+
+        is_bzImage = (protocol >= 0x0200) && (loadflags & 0x01);
+        load_address = is_bzImage ? 0x100000 : 0x10000;
+
+Note that Image/zImage kernels can be up to 512K in size, and thus use
+the entire 0x10000-0x90000 range of memory.  This means it is pretty
+much a requirement for these kernels to load the real-mode part at
+0x90000.  bzImage kernels allow much more flexibility.
+
+
+**** SPECIAL COMMAND LINE OPTIONS
+
+If the command line provided by the boot loader is entered by the
+user, the user may expect the following command line options to work.
+They should normally not be deleted from the kernel command line even
+though not all of them are actually meaningful to the kernel.  Boot
+loader authors who need additional command line options for the boot
+loader itself should get them registered in
+Documentation/kernel-parameters.txt to make sure they will not
+conflict with actual kernel options now or in the future.
+
+  vga=<mode>
+        <mode> here is either an integer (in C notation, either
+        decimal, octal, or hexadecimal) or one of the strings
+        "normal" (meaning 0xFFFF), "ext" (meaning 0xFFFE) or "ask"
+        (meaning 0xFFFD).  This value should be entered into the
+        vid_mode field, as it is used by the kernel before the command
+        line is parsed.
+
+  mem=<size>
+        <size> is an integer in C notation optionally followed by K, M
+        or G (meaning << 10, << 20 or << 30).  This specifies the end
+        of memory to the kernel. This affects the possible placement
+        of an initrd, since an initrd should be placed near end of
+        memory.  Note that this is an option to *both* the kernel and
+        the bootloader!
+
+  initrd=<file>
+        An initrd should be loaded.  The meaning of <file> is
+        obviously bootloader-dependent, and some boot loaders
+        (e.g. LILO) do not have such a command.
+
+In addition, some boot loaders add the following options to the
+user-specified command line:
+
+  BOOT_IMAGE=<file>
+        The boot image which was loaded.  Again, the meaning of <file>
+        is obviously bootloader-dependent.
+
+  auto
+        The kernel was booted without explicit user intervention.
+
+If these options are added by the boot loader, it is highly
+recommended that they are located *first*, before the user-specified
+or configuration-specified command line.  Otherwise, "init=/bin/sh"
+gets confused by the "auto" option.
+
+
+**** RUNNING THE KERNEL
+
+The kernel is started by jumping to the kernel entry point, which is
+located at *segment* offset 0x20 from the start of the real mode
+kernel.  This means that if you loaded your real-mode kernel code at
+0x90000, the kernel entry point is 9020:0000.
+
+At entry, ds = es = ss should point to the start of the real-mode
+kernel code (0x9000 if the code is loaded at 0x90000), sp should be
+set up properly, normally pointing to the top of the heap, and
+interrupts should be disabled.  Furthermore, to guard against bugs in
+the kernel, it is recommended that the boot loader sets fs = gs = ds =
+es = ss.
+
+In our example from above, we would do:
+
+        /* Note: in the case of the "old" kernel protocol, base_ptr must
+           be == 0x90000 at this point; see the previous sample code */
+
+        seg = base_ptr >> 4;
+
+        cli();  /* Enter with interrupts disabled! */
+
+        /* Set up the real-mode kernel stack */
+        _SS = seg;
+        _SP = 0x9000;   /* Load SP immediately after loading SS! */
+
+        _DS = _ES = _FS = _GS = seg;
+        jmp_far(seg+0x20, 0);   /* Run the kernel */
+
+If your boot sector accesses a floppy drive, it is recommended to
+switch off the floppy motor before running the kernel, since the
+kernel boot leaves interrupts off and thus the motor will not be
+switched off, especially if the loaded kernel has the floppy driver as
+a demand-loaded module!
+
+
+**** ADVANCED BOOT TIME HOOKS
+
+If the boot loader runs in a particularly hostile environment (such as
+LOADLIN, which runs under DOS) it may be impossible to follow the
+standard memory location requirements.  Such a boot loader may use the
+following hooks that, if set, are invoked by the kernel at the
+appropriate time.  The use of these hooks should probably be
+considered an absolutely last resort!
+
+IMPORTANT: All the hooks are required to preserve %esp, %ebp, %esi and
+%edi across invocation.
+
+  realmode_swtch:
+        A 16-bit real mode far subroutine invoked immediately before
+        entering protected mode.  The default routine disables NMI, so
+        your routine should probably do so, too.
+
+  code32_start:
+        A 32-bit flat-mode routine *jumped* to immediately after the
+        transition to protected mode, but before the kernel is
+        uncompressed.  No segments, except CS, are set up; you should
+        set them up to KERNEL_DS (0x18) yourself.
+
+        After completing your hook, you should jump to the address
+        that was in this field before your boot loader overwrote it.
diff --git a/Documentation/i386/usb-legacy-support.txt b/Documentation/i386/usb-legacy-support.txt
new file mode 100644
index 000000000000..1894cdfc69d9
--- /dev/null
+++ b/Documentation/i386/usb-legacy-support.txt
@@ -0,0 +1,44 @@
+USB Legacy support
+~~~~~~~~~~~~~~~~~~
+
+Vojtech Pavlik <vojtech@suse.cz>, January 2004
+
+
+Also known as "USB Keyboard" or "USB Mouse support" in the BIOS Setup is a
+feature that allows one to use the USB mouse and keyboard as if they were
+their classic PS/2 counterparts.  This means one can use an USB keyboard to
+type in LILO for example.
+
+It has several drawbacks, though:
+
+1) On some machines, the emulated PS/2 mouse takes over even when no USB
+   mouse is present and a real PS/2 mouse is present.  In that case the extra
+   features (wheel, extra buttons, touchpad mode) of the real PS/2 mouse may
+   not be available.
+
+2) If CONFIG_HIGHMEM64G is enabled, the PS/2 mouse emulation can cause
+   system crashes, because the SMM BIOS is not expecting to be in PAE mode.
+   The Intel E7505 is a typical machine where this happens.
+
+3) If AMD64 64-bit mode is enabled, again system crashes often happen,
+   because the SMM BIOS isn't expecting the CPU to be in 64-bit mode.  The
+   BIOS manufacturers only test with Windows, and Windows doesn't do 64-bit
+   yet.
+
+Solutions:
+
+Problem 1) can be solved by loading the USB drivers prior to loading the
+PS/2 mouse driver. Since the PS/2 mouse driver is in 2.6 compiled into
+the kernel unconditionally, this means the USB drivers need to be
+compiled-in, too.
+
+Problem 2) can currently only be solved by either disabling HIGHMEM64G
+in the kernel config or USB Legacy support in the BIOS. A BIOS update
+could help, but so far no such update exists.
+
+Problem 3) is usually fixed by a BIOS update. Check the board
+manufacturers web site. If an update is not available, disable USB
+Legacy support in the BIOS. If this alone doesn't help, try also adding
+idle=poll on the kernel command line. The BIOS may be entering the SMM
+on the HLT instruction as well.
+
diff --git a/Documentation/i386/zero-page.txt b/Documentation/i386/zero-page.txt
new file mode 100644
index 000000000000..67c053a099ed
--- /dev/null
+++ b/Documentation/i386/zero-page.txt
@@ -0,0 +1,84 @@
+Summary of boot_params layout (kernel point of view)
+     ( collected by Hans Lermen and Martin Mares )
+ 
+The contents of boot_params are used to pass parameters from the
+16-bit realmode code of the kernel to the 32-bit part. References/settings
+to it mainly are in:
+
+  arch/i386/boot/setup.S
+  arch/i386/boot/video.S
+  arch/i386/kernel/head.S
+  arch/i386/kernel/setup.c
+ 
+
+Offset  Type            Description
+------  ----            -----------
+    0   32 bytes        struct screen_info, SCREEN_INFO
+                        ATTENTION, overlaps the following !!!
+    2   unsigned short  EXT_MEM_K, extended memory size in Kb (from int 0x15)
+ 0x20   unsigned short  CL_MAGIC, commandline magic number (=0xA33F)
+ 0x22   unsigned short  CL_OFFSET, commandline offset
+                        Address of commandline is calculated:
+                          0x90000 + contents of CL_OFFSET
+                        (only taken, when CL_MAGIC = 0xA33F)
+ 0x40   20 bytes        struct apm_bios_info, APM_BIOS_INFO
+ 0x60   16 bytes        Intel SpeedStep (IST) BIOS support information
+ 0x80   16 bytes        hd0-disk-parameter from intvector 0x41
+ 0x90   16 bytes        hd1-disk-parameter from intvector 0x46
+
+ 0xa0   16 bytes        System description table truncated to 16 bytes.
+                        ( struct sys_desc_table_struct )
+ 0xb0 - 0x13f           Free. Add more parameters here if you really need them.
+ 0x140- 0x1be           EDID_INFO Video mode setup
+
+0x1c4   unsigned long   EFI system table pointer
+0x1c8   unsigned long   EFI memory descriptor size
+0x1cc   unsigned long   EFI memory descriptor version
+0x1d0   unsigned long   EFI memory descriptor map pointer
+0x1d4   unsigned long   EFI memory descriptor map size
+0x1e0   unsigned long   ALT_MEM_K, alternative mem check, in Kb
+0x1e8   char            number of entries in E820MAP (below)
+0x1e9   unsigned char   number of entries in EDDBUF (below)
+0x1ea   unsigned char   number of entries in EDD_MBR_SIG_BUFFER (below)
+0x1f1   char            size of setup.S, number of sectors
+0x1f2   unsigned short  MOUNT_ROOT_RDONLY (if !=0)
+0x1f4   unsigned short  size of compressed kernel-part in the
+                        (b)zImage-file (in 16 byte units, rounded up)
+0x1f6   unsigned short  swap_dev (unused AFAIK)
+0x1f8   unsigned short  RAMDISK_FLAGS
+0x1fa   unsigned short  VGA-Mode (old one)
+0x1fc   unsigned short  ORIG_ROOT_DEV (high=Major, low=minor)
+0x1ff   char            AUX_DEVICE_INFO
+
+0x200   short jump to start of setup code aka "reserved" field.
+0x202   4 bytes         Signature for SETUP-header, ="HdrS"
+0x206   unsigned short  Version number of header format
+                        Current version is 0x0201...
+0x208   8 bytes         (used by setup.S for communication with boot loaders,
+                         look there)
+0x210   char            LOADER_TYPE, = 0, old one
+                        else it is set by the loader:
+                        0xTV: T=0 for LILO
+                                1 for Loadlin
+                                2 for bootsect-loader
+                                3 for SYSLINUX
+                                4 for ETHERBOOT
+                                V = version
+0x211   char            loadflags:
+                        bit0 = 1: kernel is loaded high (bzImage)
+                        bit7 = 1: Heap and pointer (see below) set by boot
+                                  loader.
+0x212   unsigned short  (setup.S)
+0x214   unsigned long   KERNEL_START, where the loader started the kernel
+0x218   unsigned long   INITRD_START, address of loaded ramdisk image
+0x21c   unsigned long   INITRD_SIZE, size in bytes of ramdisk image
+0x220   4 bytes         (setup.S)
+0x224   unsigned short  setup.S heap end pointer
+0x226   unsigned short  zero_pad
+0x228   unsigned long   cmd_line_ptr
+0x22c   unsigned long   ramdisk_max
+0x230   16 bytes        trampoline
+0x290 - 0x2cf           EDD_MBR_SIG_BUFFER (edd.S)
+0x2d0 - 0x600           E820MAP
+0x600 - 0x7ff           EDDBUF (edd.S) for disk signature read sector
+0x600 - 0x7eb           EDDBUF (edd.S) for edd data