From ee287587dafd77fd211e50637561224605c214b4 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Wed, 14 Jan 2009 16:07:38 -0800 Subject: bzip2/lzma: update boot protocol specification Impact: documentation Update the boot protocol specification to include the currently supported file formats and their magic numbers. Signed-off-by: H. Peter Anvin --- Documentation/x86/boot.txt | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'Documentation/x86/boot.txt') diff --git a/Documentation/x86/boot.txt b/Documentation/x86/boot.txt index fcdc62b3c3d..9ac70ffe2b7 100644 --- a/Documentation/x86/boot.txt +++ b/Documentation/x86/boot.txt @@ -542,7 +542,10 @@ Protocol: 2.08+ The payload may be compressed. The format of both the compressed and uncompressed data should be determined using the standard magic - numbers. Currently only gzip compressed ELF is used. + numbers. The currently supported compression formats are gzip + (magic numbers 1F 8B or 1F 9E), bzip2 (magic number 42 5A) and LZMA + (magic number 5D 00). The uncompressed payload is currently always ELF + (magic number 7F 45 4C 46). Field name: payload_length Type: read -- cgit v1.2.3 From e56d0cfe7790fd3218ae4f6aae1335547fea8763 Mon Sep 17 00:00:00 2001 From: Baodong Chen Date: Thu, 8 Jan 2009 19:24:29 +0800 Subject: Documentation/x86/boot.txt: modify fieldname Modify field names to the right ones: - start_sys was changed to start_sys_seg - iinitrd_addr_max was changed to ramdisk_max - pad2 was changed to pad2 and pad3 - readmode_swtch was changed to realmode_swtch Signed-off-by: Baodong Chen <[email]chenbdchenbd@gmail.com[email]> Acked-by: Jiri Kosina Signed-off-by: Ingo Molnar --- Documentation/x86/boot.txt | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) (limited to 'Documentation/x86/boot.txt') diff --git a/Documentation/x86/boot.txt b/Documentation/x86/boot.txt index 7b4596ac412..12299697b7c 100644 --- a/Documentation/x86/boot.txt +++ b/Documentation/x86/boot.txt @@ -158,7 +158,7 @@ Offset Proto Name Meaning 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) +020C/2 2.00+ start_sys_seg 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 @@ -170,10 +170,11 @@ Offset Proto Name Meaning 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 +022C/4 2.03+ ramdisk_max Highest legal initrd address 0230/4 2.05+ kernel_alignment Physical addr alignment required for kernel 0234/1 2.05+ relocatable_kernel Whether kernel is relocatable or not -0235/3 N/A pad2 Unused +0235/1 N/A pad2 Unused +0236/2 N/A pad3 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 @@ -299,14 +300,14 @@ Protocol: 2.00+ e.g. 0x0204 for version 2.04, and 0x0a11 for a hypothetical version 10.17. -Field name: readmode_swtch +Field name: realmode_swtch Type: modify (optional) Offset/size: 0x208/4 Protocol: 2.00+ Boot loader hook (see ADVANCED BOOT LOADER HOOKS below.) -Field name: start_sys +Field name: start_sys_seg Type: read Offset/size: 0x20c/2 Protocol: 2.00+ @@ -468,7 +469,7 @@ Protocol: 2.02+ zero, the kernel will assume that your boot loader does not support the 2.02+ protocol. -Field name: initrd_addr_max +Field name: ramdisk_max Type: read Offset/size: 0x22c/4 Protocol: 2.03+ -- cgit v1.2.3