x86: doc: move x86-generic documentation from Doc/x86/i386

The boot protocol, USB legacy support, and zero-page documentation is
common to the x86 platform, not i386-specific.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 31 insertions, 0 deletions

diff --git a/Documentation/x86/zero-page.txt b/Documentation/x86/zero-page.txt
new file mode 100644
index 000000000000..169ad423a3d1
--- /dev/null
+++ b/Documentation/x86/zero-page.txt
@@ -0,0 +1,31 @@
+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:
+
+  include/asm-x86/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)
+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)
+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_map (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)
+290/040 ALL     edd_mbr_sig_buffer EDD MBR signatures
+2D0/A00 ALL     e820_map        E820 memory map table
+                                (array of struct e820entry)
+D00/1EC ALL     eddbuf          EDD data (array of struct edd_info)