From 98360be0fefd58bf27df03c47d887dd676a31d73 Mon Sep 17 00:00:00 2001 From: Sascha Hauer Date: Tue, 17 Jun 2014 10:27:03 +0200 Subject: Documentation: remove doxygen documentation The doxygen documentation is long outdated. Remove it. It will be replaced with sphinx based documentation later. Signed-off-by: Sascha Hauer --- arch/x86/mach-x86.dox | 128 -------------------------------------------------- 1 file changed, 128 deletions(-) delete mode 100644 arch/x86/mach-x86.dox (limited to 'arch/x86/mach-x86.dox') diff --git a/arch/x86/mach-x86.dox b/arch/x86/mach-x86.dox deleted file mode 100644 index 661e905bac..0000000000 --- a/arch/x86/mach-x86.dox +++ /dev/null @@ -1,128 +0,0 @@ -/* This document is intended to provide the developer with information - * how to integrate a new CPU (MACH) into this part of the barebox tree - */ - -/** @page dev_x86_mach barebox on x86 at runtime - -@section mach_x86_memory_layout barebox's memory layout (BIOS based) - -@a barebox uses the following memory layout at runtime when it still depends -on some kind of BIOS function: - -@verbatim - Addresses ------------------------- - - seg:off flat - -xxxx:xxxx 0x01xxxxxx end of barebox's malloc area - . . -xxxx:xxxx 0x01000000 start of barebox's malloc area - . . - . . (used while loading a Linux kernel of type 'bzImage') - . . -xxxx:xxxx 0x00100000 start of extended memory and malloc area - . . - . . (the big hole) - . . -9000:ffff 0x0009ffff end of expected real mode memory - . . - . . (used while loading a Linux kernel of type 'bzImage') - . . -9000:0000 0x00090000 end of used lower real mode memory - . . - . . - . . Flat mode stack (about 32 kiB) - . . bss - . . Data - . . Text -0000:7e00 0x00007e00 Real and flat mode barebox code -0000:7c00 0x00007c00 MBR initial boot loader code -0000:7a00 0x00007a00 location of the indirect sector (while booting only) - below: real mode stack -@endverbatim - -@note The start address of 0x0000:7c000 is a fixed one, defined by the BIOS. -So, for a BIOS based @a barebox this address can't be changed. - -While the @a barebox code is runnung in flat mode, all interrupts are disabled. -But in the CPU only. All other interrupt settings are still valid. This is -required to be able to call real mode code from inside @a barebox flat mode -code. Thats why not the PIC is touched nor the IDT. - -@todo Add some notes about drive numbers used by the BIOS. They may change -if one change orders in the BIOS setup. Drive orders and numbers may be -different at BIOS runtime and Linux runtime! But these numbers are required -at BIOS runtime for booting and the persistant environment storage. - -@attention Currently there is a 4 GiB limit for the disk sizes! - -@section mach_x86_image_layout barebox's image layout - -@a barebox's binary image layout - -@verbatim - Offset Content - - 0x????? - . 32 bit barebox code - . - . 16 bit bootstrap code, BIOS calling code - 0x00400 - 0x003ff - . indirect sector - 0x00200 - 0x001ff - . MBR - 0x00000 -@endverbatim - -The "indirect sector" is a free area in the image where the sector information -gets stored when this image will be written to a boot media. This information -is required to load all parts of the image from the boot media at runtime. - -The image gets installed in two ways onto the boot media, depending on the -need for a persistant storage. - -@subsection mach_x86_drive_layout_wops barebox's boot media layout without persistant storage - -In this case @a barebox's persistant storage is anywhere: - -@verbatim - Sector Content ---------------------------- - X start of first partition - . - ? end of the binary image - . 32 bit barebox code - 2 16 bit bootstrap code, BIOS calling code - 1 indirect sector - 0 MBR, Partition table, boot code -@endverbatim - -@subsection mach_x86_drive_layout_wps barebox's boot media layout with persistant storage - -@a barebox's persistant storage is part of the boot media (more -space required in front of the first partition) and interferes with the -boot loader image itself: - -@verbatim - Sector Content ---------------------------- - X start of first partition - . - n+? end of the binary image - . 32 bit barebox code - n+2 16 bit bootstrap code, BIOS calling code - n+1 indirect sector - n end of persistant environment storage - . - 1 start of persistant environment storage - 0 MBR, Partition table, boot code -@endverbatim - -The information where the persistant storage is located is also stored into -the MBR at specific locations by @p setupmbr. The @a barebox runtime will use -it to load and store all environment relevant data. - -*/ -- cgit v1.2.3