summaryrefslogtreecommitdiffstats
path: root/Documentation/x86/zero-page.txt
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /Documentation/x86/zero-page.txt
parentInitial commit. (diff)
downloadlinux-c109f8d9e922037b3fa45f46d78384d49db8ad76.tar.xz
linux-c109f8d9e922037b3fa45f46d78384d49db8ad76.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'Documentation/x86/zero-page.txt')
-rw-r--r--Documentation/x86/zero-page.txt40
1 files changed, 40 insertions, 0 deletions
diff --git a/Documentation/x86/zero-page.txt b/Documentation/x86/zero-page.txt
new file mode 100644
index 000000000..97b7adbce
--- /dev/null
+++ b/Documentation/x86/zero-page.txt
@@ -0,0 +1,40 @@
+The additional fields in struct boot_params as a part of 32-bit boot
+protocol of kernel. These should be filled by bootloader or 16-bit
+real-mode setup code of the kernel. References/settings to it mainly
+are in:
+
+ arch/x86/include/uapi/asm/bootparam.h
+
+
+Offset Proto Name Meaning
+/Size
+
+000/040 ALL screen_info Text mode or frame buffer information
+ (struct screen_info)
+040/014 ALL apm_bios_info APM BIOS information (struct apm_bios_info)
+058/008 ALL tboot_addr Physical address of tboot shared page
+060/010 ALL ist_info Intel SpeedStep (IST) BIOS support information
+ (struct ist_info)
+080/010 ALL hd0_info hd0 disk parameter, OBSOLETE!!
+090/010 ALL hd1_info hd1 disk parameter, OBSOLETE!!
+0A0/010 ALL sys_desc_table System description table (struct sys_desc_table),
+ OBSOLETE!!
+0B0/010 ALL olpc_ofw_header OLPC's OpenFirmware CIF and friends
+0C0/004 ALL ext_ramdisk_image ramdisk_image high 32bits
+0C4/004 ALL ext_ramdisk_size ramdisk_size high 32bits
+0C8/004 ALL ext_cmd_line_ptr cmd_line_ptr high 32bits
+140/080 ALL edid_info Video mode setup (struct edid_info)
+1C0/020 ALL efi_info EFI 32 information (struct efi_info)
+1E0/004 ALL alk_mem_k Alternative mem check, in KB
+1E4/004 ALL scratch Scratch field for the kernel setup code
+1E8/001 ALL e820_entries Number of entries in e820_table (below)
+1E9/001 ALL eddbuf_entries Number of entries in eddbuf (below)
+1EA/001 ALL edd_mbr_sig_buf_entries Number of entries in edd_mbr_sig_buffer
+ (below)
+1EB/001 ALL kbd_status Numlock is enabled
+1EC/001 ALL secure_boot Secure boot is enabled in the firmware
+1EF/001 ALL sentinel Used to detect broken bootloaders
+290/040 ALL edd_mbr_sig_buffer EDD MBR signatures
+2D0/A00 ALL e820_table E820 memory map table
+ (array of struct e820_entry)
+D00/1EC ALL eddbuf EDD data (array of struct edd_info)