diff options
| author | Rusty Russell <rusty@rustcorp.com.au> | 2007-10-21 16:41:33 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-10-22 08:13:17 -0700 |
| commit | e5371ac566b6794f2125393b6850909de9e16f58 (patch) | |
| tree | ac08bad552ebfb1f0deb55f88230369f236b8ac0 /Documentation/i386/boot.txt | |
| parent | 55b70a0300b873c0ec7ea6e33752af56f41250ce (diff) | |
update boot spec to 2.07
Updates for version 2.07 of the boot protocol. This includes:
load_flags.KEEP_SEGMENTS- flag to request/inhibit segment reloads
hardware_subarch - what subarchitecture we're booting under
hardware_subarch_data - per-architecture data
The intention of these changes is to make booting a paravirtualized
kernel work via the normal Linux boot protocol.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'Documentation/i386/boot.txt')
| -rw-r--r-- | Documentation/i386/boot.txt | 34 |
1 files changed, 33 insertions, 1 deletions
diff --git a/Documentation/i386/boot.txt b/Documentation/i386/boot.txt index 35985b34d5a..2f75e750e4f 100644 --- a/Documentation/i386/boot.txt +++ b/Documentation/i386/boot.txt @@ -168,6 +168,8 @@ Offset Proto Name Meaning 0234/1 2.05+ relocatable_kernel Whether kernel is relocatable or not 0235/3 N/A pad2 Unused 0238/4 2.06+ cmdline_size Maximum size of the kernel command line +023C/4 2.07+ hardware_subarch Hardware subarchitecture +0240/8 2.07+ hardware_subarch_data Subarchitecture-specific data (1) For backwards compatibility, if the setup_sects field contains 0, the real value is 4. @@ -204,7 +206,7 @@ boot loaders can ignore those fields. The byte order of all fields is littleendian (this is x86, after all.) -Field name: setup_secs +Field name: setup_sects Type: read Offset/size: 0x1f1/1 Protocol: ALL @@ -356,6 +358,13 @@ Protocol: 2.00+ - If 0, the protected-mode code is loaded at 0x10000. - If 1, the protected-mode code is loaded at 0x100000. + Bit 6 (write): KEEP_SEGMENTS + Protocol: 2.07+ + - if 0, reload the segment registers in the 32bit entry point. + - if 1, do not reload the segment registers in the 32bit entry point. + Assume that %cs %ds %ss %es are all set to flat segments with + a base of 0 (or the equivalent for their environment). + Bit 7 (write): CAN_USE_HEAP Set this bit to 1 to indicate that the value entered in the heap_end_ptr is valid. If this field is clear, some setup code @@ -480,6 +489,29 @@ Protocol: 2.06+ cmdline_size characters. With protocol version 2.05 and earlier, the maximum size was 255. +Field name: hardware_subarch +Type: write +Offset/size: 0x23c/4 +Protocol: 2.07+ + + In a paravirtualized environment the hardware low level architectural + pieces such as interrupt handling, page table handling, and + accessing process control registers needs to be done differently. + + This field allows the bootloader to inform the kernel we are in one + one of those environments. + + 0x00000000 The default x86/PC environment + 0x00000001 lguest + 0x00000002 Xen + +Field name: hardware_subarch_data +Type: write +Offset/size: 0x240/8 +Protocol: 2.07+ + + A pointer to data that is specific to hardware subarch + **** THE KERNEL COMMAND LINE |