@@ -359,6 +359,7 @@ executable header.
* Console header tags::
* Module alignment tag::
* EFI boot services tag::
+* Relocatable header tag::
@end menu
@@ -685,6 +686,47 @@ u32 | size = 8 |
This tag indicates that payload supports starting without
terminating boot services.
+@node Relocatable header tag
+@subsection Relocatable header tag
+
+@example
+@group
+ +-------------------+
+u16 | type = 10 |
+u16 | flags |
+u32 | size = 24 |
+u32 | min_addr |
+u32 | max_addr |
+u32 | align |
+u32 | preference |
+ +-------------------+
+@end group
+@end example
+
+This tag indicates that image is relocatable.
+
+The meaning of each field is as follows:
+
+@table @code
+@item min_addr
+Lowest possible physical address at which image should be loaded.
+The bootloader cannot load any part of image below this address.
+
+@item max_addr
+Highest possible physical address at which loaded image should end.
+The bootloader cannot load any part of image above this address.
+
+@item align
+Image alignment in memory, e.g. 4096.
+
+@item preference
+It contains load address placement suggestion for boot loader.
+Boot loader should follow it. @samp{0} means none, @samp{1} means
+load image at lowest possible address but not lower than min_addr
+and @samp{2} means load image at highest possible address but not
+higher than max_addr.
+@end table
+
@node Machine state
@section MIPS machine state
@@ -1316,6 +1358,20 @@ u64 | pointer |
This tag contains pointer to EFI amd64 image handle.
Usually it is boot loader image handle.
+@subsection Image load base physical address
+@example
+@group
+ +-------------------+
+u32 | type = 21 |
+u32 | size = 12 |
+u32 | load_base_addr |
+ +-------------------+
+@end group
+@end example
+
+This tag contains image load base physical address. It is
+provided only if image has relocatable header tag.
+
@node Examples
@chapter Examples
@@ -62,6 +62,7 @@
#define MULTIBOOT_TAG_TYPE_EFI_BS 18
#define MULTIBOOT_TAG_TYPE_EFI32_IH 19
#define MULTIBOOT_TAG_TYPE_EFI64_IH 20
+#define MULTIBOOT_TAG_TYPE_LOAD_BASE_ADDR 21
#define MULTIBOOT_HEADER_TAG_END 0
#define MULTIBOOT_HEADER_TAG_INFORMATION_REQUEST 1
@@ -73,11 +74,16 @@
#define MULTIBOOT_HEADER_TAG_EFI_BS 7
#define MULTIBOOT_HEADER_TAG_ENTRY_ADDRESS_EFI32 8
#define MULTIBOOT_HEADER_TAG_ENTRY_ADDRESS_EFI64 9
+#define MULTIBOOT_HEADER_TAG_RELOCATABLE 10
#define MULTIBOOT_ARCHITECTURE_I386 0
#define MULTIBOOT_ARCHITECTURE_MIPS32 4
#define MULTIBOOT_HEADER_TAG_OPTIONAL 1
+#define MULTIBOOT_LOAD_PREFERENCE_NONE 0
+#define MULTIBOOT_LOAD_PREFERENCE_LOW 1
+#define MULTIBOOT_LOAD_PREFERENCE_HIGH 2
+
#define MULTIBOOT_CONSOLE_FLAGS_CONSOLE_REQUIRED 1
#define MULTIBOOT_CONSOLE_FLAGS_EGA_TEXT_SUPPORTED 2
@@ -162,6 +168,17 @@ struct multiboot_header_tag_module_align
multiboot_uint32_t size;
};
+struct multiboot_header_tag_relocatable
+{
+ multiboot_uint16_t type;
+ multiboot_uint16_t flags;
+ multiboot_uint32_t size;
+ multiboot_uint32_t min_addr;
+ multiboot_uint32_t max_addr;
+ multiboot_uint32_t align;
+ multiboot_uint32_t preference;
+};
+
struct multiboot_color
{
multiboot_uint8_t red;
@@ -388,6 +405,13 @@ struct multiboot_tag_efi64_ih
multiboot_uint64_t pointer;
};
+struct multiboot_tag_load_base_addr
+{
+ multiboot_uint32_t type;
+ multiboot_uint32_t size;
+ multiboot_uint32_t load_base_addr;
+};
+
#endif /* ! ASM_FILE */
#endif /* ! MULTIBOOT_HEADER */
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com> --- v2 - suggestions/fixes: - add missing the articles (suggested by Andrew Cooper), - various minor cleanups and fixes (suggested by Andrew Cooper). --- doc/multiboot.texi | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++ doc/multiboot2.h | 24 ++++++++++++++++++++++ 2 files changed, 80 insertions(+)