openwrt/upstream - upstream openwrt

	Commit message (Expand)	Author	Age	Files	Lines
*	tools/llvm-bpf: move tarball packing to target/llvm-bpf	Felix Fietkau	2021-11-22	1	-2/+7
*	build: make <subdir>/install opt-in, use it for target/ only	Felix Fietkau	2017-02-09	1	-0/+1
*	sdk: depend on linux/install	Jo-Philipp Wich	2016-11-04	1	-0/+1
*	target: do not make target//install depend on target//compile - removes one...	Felix Fietkau	2012-06-06	1	-4/+1
*	imagebuilder: fix parallel building (closes #11117)	Gabor Juhos	2012-03-13	1	-1/+4
*	Add a target (CONFIG_MAKE_CONFIG) that creates an exportable toolchain. The t...	Felix Fietkau	2009-11-14	1	-2/+2
*	some more build system cleanup	Felix Fietkau	2008-08-17	1	-1/+0
*	large improvement for parallel builds. works without V=99 now and without war...	Felix Fietkau	2008-06-09	1	-0/+1
*	fix a dependency bug	Felix Fietkau	2007-08-30	1	-5/+3
*	only build sdk and imagebuilder at target/install time	Felix Fietkau	2007-07-31	1	-2/+2
*	next round of cleanup, convert target/ - make -j works now ;)	Felix Fietkau	2007-07-30	1	-45/+13
*	don't run the image prereq check if the image directory does not exist	Felix Fietkau	2007-07-16	1	-1/+1
*	Rename 'refresh' to 'update' and make the new 'refresh' actually refresh all ...	Felix Fietkau	2007-06-04	1	-1/+1
*	implement quilt handling for the kernel tree ... and there was much rejoicing!	Felix Fietkau	2007-06-03	1	-1/+1
*	the default_subtargets template was a bad idea, since different makefiles req...	Felix Fietkau	2007-04-18	1	-1/+2
*	use default_subtargets in package/Makefile and target/Makefile	Felix Fietkau	2007-02-26	1	-11/+1
*	clean up a few things in image build makefiles and fix unnecessary grub rebuilds	Felix Fietkau	2007-02-25	1	-1/+1
*	Fix config checks for Image Builder and SDK - only build them when requested....	Felix Fietkau	2007-01-14	1	-1/+9
*	Add initial version of the new Image Builder It's still a bit rough in a few ...	Felix Fietkau	2007-01-10	1	-6/+8
*	move target/utils to tools/firmware-utils	Felix Fietkau	2006-12-06	1	-2/+1
*	move target/image/platform to target/linux/platform/image platform directorie...	Mike Baker	2006-11-28	1	-4/+7
*	add prereq checks for target/linux/* and target/image/*, check for fdisk for ...	Felix Fietkau	2006-11-18	1	-0/+4
*	leave out the ccache directory when copying the staging dir into the sdk (#843)	Felix Fietkau	2006-10-14	1	-1/+0
*	finally move buildroot-ng to trunk	Felix Fietkau	2016-03-20	1	-0/+49

/* * bootsect.S * * This is setup.S from the linux 2.6.9 source code, * with heavy cuts and changes for mbootpack * November 2004 Tim Deegan <tjd21@cl.cam.ac.uk> * * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of the * License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA * 02111-1307, USA. * * $Id: setup.S,v 1.4 2005/03/23 10:39:03 tjd21 Exp $ * */ #include "mbootpack.h" /* * setup.S Copyright (C) 1991, 1992 Linus Torvalds * * setup.s is responsible for getting the system data from the BIOS, * and putting them into the appropriate places in system memory. * both setup.s and system has been loaded by the bootblock. * * This code asks the bios for memory/disk/other parameters, and * puts them in a "safe" place: 0x90000-0x901FF, ie where the * boot-block used to be. It is then up to the protected mode * system to read them from there before the area is overwritten * for buffer-blocks. * * Move PS/2 aux init code to psaux.c * (troyer@saifr00.cfsat.Honeywell.COM) 03Oct92 * * some changes and additional features by Christoph Niemann, * March 1993/June 1994 (Christoph.Niemann@linux.org) * * add APM BIOS checking by Stephen Rothwell, May 1994 * (sfr@canb.auug.org.au) * * High load stuff, initrd support and position independency * by Hans Lermen & Werner Almesberger, February 1996 * <lermen@elserv.ffm.fgan.de>, <almesber@lrc.epfl.ch> * * Video handling moved to video.S by Martin Mares, March 1996 * <mj@k332.feld.cvut.cz> * * Extended memory detection scheme retwiddled by orc@pell.chi.il.us (david * parsons) to avoid loadlin confusion, July 1997 * * Transcribed from Intel (as86) -> AT&T (gas) by Chris Noe, May 1999. * <stiker@northlink.com> * * Fix to work around buggy BIOSes which dont use carry bit correctly * and/or report extended memory in CX/DX for e801h memory size detection * call. As a result the kernel got wrong figures. The int15/e801h docs * from Ralf Brown interrupt list seem to indicate AX/BX should be used * anyway. So to avoid breaking many machines (presumably there was a reason * to orginally use CX/DX instead of AX/BX), we do a kludge to see * if CX/DX have been changed in the e801 call and if so use AX/BX . * Michael Miller, April 2001 <michaelm@mjmm.org> * * New A20 code ported from SYSLINUX by H. Peter Anvin. AMD Elan bugfixes * by Robert Schwebel, December 2001 <robert@schwebel.de> */ /* #include <linux/config.h> #include <asm/segment.h> #include <linux/version.h> #include <linux/compile.h> #include <asm/boot.h> #include <asm/e820.h> #include <asm/page.h> */ /* Definitions that should have come from these includes */ #define DEF_INITSEG 0x9000 #define DEF_SYSSEG 0x1000 #define DEF_SETUPSEG 0x9020 #define DEF_SYSSIZE 0x7F00 #define NORMAL_VGA 0xffff #define EXTENDED_VGA 0xfffe #define ASK_VGA 0xfffd #define GDT_ENTRY_BOOT_CS 2 #define __BOOT_CS (GDT_ENTRY_BOOT_CS * 8) #define GDT_ENTRY_BOOT_DS (GDT_ENTRY_BOOT_CS + 1) #define __BOOT_DS (GDT_ENTRY_BOOT_DS * 8) #define __PAGE_OFFSET (0xC0000000) #define E820MAP 0x2d0 /* our map */ #define E820MAX 32 /* number of entries in E820MAP */ #define E820NR 0x1e8 /* # entries in E820MAP */ #define E820_RAM 1 #define E820_RESERVED 2 #define E820_ACPI 3 /* usable as RAM once ACPI tables have been read */ #define E820_NVS 4 #define __BIG_KERNEL__ /* Signature words to ensure LILO loaded us right */ #define SIG1 0xAA55 #define SIG2 0x5A5A INITSEG = DEF_INITSEG # 0x9000, we move boot here, out of the way SYSSEG = DEF_SYSSEG # 0x1000, system loaded at 0x10000 (65536). SETUPSEG = DEF_SETUPSEG # 0x9020, this is the current segment # ... and the former contents of CS DELTA_INITSEG = SETUPSEG - INITSEG # 0x0020 .code16 .globl _start, begtext, begdata, begbss, endtext, enddata, endbss .text begtext: .data begdata: .bss begbss: .text _start: start: jmp trampoline # This is the setup header, and it must start at %cs:2 (old 0x9020:2) .ascii "HdrS" # header signature .word 0x0203 # header version number (>= 0x0105) # or else old loadlin-1.5 will fail) realmode_swtch: .word 0, 0 # default_switch, SETUPSEG start_sys_seg: .word SYSSEG .word kernel_version # pointing to kernel version string # above section of header is compatible # with loadlin-1.5 (header v1.5). Don't # change it. type_of_loader: .byte 0 # = 0, old one (LILO, Loadlin, # Bootlin, SYSLX, bootsect...) # See Documentation/i386/boot.txt for # assigned ids # flags, unused bits must be zero (RFU) bit within loadflags loadflags: LOADED_HIGH = 1 # If set, the kernel is loaded high CAN_USE_HEAP = 0x80 # If set, the loader also has set # heap_end_ptr to tell how much # space behind setup.S can be used for # heap purposes. # Only the loader knows what is free #ifndef __BIG_KERNEL__ .byte 0 #else .byte LOADED_HIGH #endif setup_move_size: .word 0x8000 # size to move, when setup is not # loaded at 0x90000. We will move setup # to 0x90000 then just before jumping # into the kernel. However, only the # loader knows how much data behind # us also needs to be loaded. /* N.B. these next addresses are entirely ignored by this code -- it * assumes it was loaded with the 32bit code at 0x100000, and doesn't * touch the ramdisk. */ code32_start: # here loaders can put a different # start address for 32-bit code. #ifndef __BIG_KERNEL__ .long 0x1000 # 0x1000 = default for zImage #else .long 0x100000 # 0x100000 = default for big kernel #endif ramdisk_image: .long 0 # address of loaded ramdisk image # Here the loader puts the 32-bit # address where it loaded the image. # This only will be read by the kernel. ramdisk_size: .long 0 # its size in bytes bootsect_kludge: .long 0 # obsolete heap_end_ptr: .word modelist+1024 # (Header version 0x0201 or later) # space from here (exclusive) down to # end of setup code can be used by setup # for local heap purposes. pad1: .word 0 cmd_line_ptr: .long 0 # (Header version 0x0202 or later) # If nonzero, a 32-bit pointer # to the kernel command line. # The command line should be # located between the start of # setup and the end of low # memory (0xa0000), or it may # get overwritten before it # gets read. If this field is # used, there is no longer # anything magical about the # 0x90000 segment; the setup # can be located anywhere in # low memory 0x10000 or higher. ramdisk_max: .long (-__PAGE_OFFSET-(512 << 20)-1) & 0x7fffffff # (Header version 0x0203 or later) # The highest safe address for # the contents of an initrd /* Add more known locations: the image builder will overwrite * these with the entry point and MBI location for the multiboot kernel. * These offsets *must* match the definitions in buildimage.c */ entry_address: .long 0 # This will be offset 0x30 (0x230 from b'sect) mbi_address: .long 0 # This will be offset 0x34 /* Storage space for the size of memory */ highmem_size: .long 0 trampoline: call start_of_setup .space 1024 # End of setup header ##################################################### start_of_setup: # Bootlin depends on this being done early movw $0x01500, %ax movb $0x81, %dl int $0x13 #ifdef SAFE_RESET_DISK_CONTROLLER # Reset the disk controller. movw $0x0000, %ax movb $0x80, %dl int $0x13 #endif # Set %ds = %cs, we know that SETUPSEG = %cs at this point movw %cs, %ax # aka SETUPSEG movw %ax, %ds # Check signature at end of setup cmpw $SIG1, setup_sig1 jne bad_sig cmpw $SIG2, setup_sig2 jne bad_sig jmp good_sig1 # Routine to print asciiz string at ds:si prtstr: lodsb andb %al, %al jz fin call prtchr jmp prtstr fin: ret # Space printing prtsp2: call prtspc # Print double space prtspc: movb $0x20, %al # Print single space (note: fall-thru) # Part of above routine, this one just prints ascii al prtchr: pushw %ax pushw %cx movw $7,%bx movw $0x01, %cx movb $0x0e, %ah int $0x10 popw %cx popw %ax ret beep: movb $0x07, %al jmp prtchr no_sig_mess: .string "No setup signature found ..." good_sig1: jmp good_sig # We now have to find the rest of the setup code/data bad_sig: movw %cs, %ax # SETUPSEG subw $DELTA_INITSEG, %ax # INITSEG movw %ax, %ds xorb %bh, %bh movb (497), %bl # get setup sect from bootsect subw $4, %bx # LILO loads 4 sectors of setup shlw $8, %bx # convert to words (1sect=2^8 words) movw %bx, %cx shrw $3, %bx # convert to segment addw $SYSSEG, %bx movw %bx, %cs:start_sys_seg # Move rest of setup code/data to here movw $2048, %di # four sectors loaded by LILO subw %si, %si pushw %cs popw %es movw $SYSSEG, %ax movw %ax, %ds rep movsw movw %cs, %ax # aka SETUPSEG movw %ax, %ds cmpw $SIG1, setup_sig1 jne no_sig cmpw $SIG2, setup_sig2 jne no_sig jmp good_sig no_sig: lea no_sig_mess, %si call prtstr no_sig_loop: hlt jmp no_sig_loop mb_hello_mess1: .string "mboot" good_sig: lea mb_hello_mess1, %si call prtstr movw %cs, %ax # aka SETUPSEG subw $DELTA_INITSEG, %ax # aka INITSEG movw %ax, %ds # Check if an old loader tries to load a big-kernel testb $LOADED_HIGH, %cs:loadflags # Do we have a big kernel? jz loader_ok # No, no danger for old loaders. cmpb $0, %cs:type_of_loader # Do we have a loader that # can deal with us? jnz loader_ok # Yes, continue. pushw %cs # No, we have an old loader, popw %ds # die. lea loader_panic_mess, %si call prtstr jmp no_sig_loop loader_panic_mess: .string "Wrong loader, giving up..." loader_ok: # Get memory size (extended mem, kB) /* We'll be storing this in highmem_size, to be copied to the mbi */ # Try three different memory detection schemes. First, try # e820h, which lets us assemble a memory map, then try e801h, # which returns a 32-bit memory size, and finally 88h, which # returns 0-64m xorl %edx, %edx xorl %eax, %eax movl %eax, (0x1e0) movl %eax, highmem_size movb %al, (E820NR) # method E820H: # the memory map from hell. e820h returns memory classified into # a whole bunch of different types, and allows memory holes and # everything. We scan through this memory map and build a list # of the first 32 memory areas, which we return at [E820MAP]. # This is documented at http://www.acpi.info/, in the ACPI 2.0 specification. #define SMAP 0x534d4150 meme820: xorl %ebx, %ebx # continuation counter movw $E820MAP, %di # point into the whitelist # so we can have the bios # directly write into it. jmpe820: movl $0x0000e820, %eax # e820, upper word zeroed movl $SMAP, %edx # ascii 'SMAP' movl $20, %ecx # size of the e820rec pushw %ds # data record. popw %es int $0x15 # make the call jc bail820 # fall to e801 if it fails cmpl $SMAP, %eax # check the return is `SMAP' jne bail820 # fall to e801 if it fails # cmpl $1, 16(%di) # is this usable memory? # jne again820 # If this is usable memory, we save it by simply advancing %di by # sizeof(e820rec). # good820: movb (E820NR), %al # up to 32 entries cmpb $E820MAX, %al jnl bail820 incb (E820NR) movw %di, %ax addw $20, %ax movw %ax, %di again820: cmpl $0, %ebx # check to see if jne jmpe820 # %ebx is set to EOF /* Multiboot spec says high mem should be the address of the first * upper memory hole, minus 1 MB */ xorl %ebx, %ebx xorl %ecx, %ecx xorl %edx, %edx movw $E820MAP, %di # Start at the beginning calc_highmem_loop: cmpl $1, 16(%di) # is it usable memory? jnz calc_highmem_next cmpl $0, 4(%di) # is base < 4GB? jnz calc_highmem_next cmpl $0x100000, 0(%di) # is base <= 1MB? jg calc_highmem_next movl 8(%di), %ecx # Calculate base+length shrl $10, %ecx # in kilobytes movl 12(%di), %edx shll $22, %edx orl %edx, %ecx movl 0(%di), %edx shrl $10, %edx addl %edx, %ecx subl $1024, %ecx # - 1 MB cmpl %cs:highmem_size, %ecx jl calc_highmem_next movl %ecx, %cs:highmem_size calc_highmem_next: add $1, %bl add $20, %di cmp %bl, (E820NR) je calc_highmem_done jmp calc_highmem_loop calc_highmem_done: bail820: # method E801H: # memory size is in 1k chunksizes, to avoid confusing loadlin. meme801: stc # fix to work around buggy xorw %cx,%cx # BIOSes which dont clear/set xorw %dx,%dx # carry on pass/error of # e801h memory size call # or merely pass cx,dx though # without changing them. movw $0xe801, %ax int $0x15 jc mem88 cmpw $0x0, %cx # Kludge to handle BIOSes jne e801usecxdx # which report their extended cmpw $0x0, %dx # memory in AX/BX rather than jne e801usecxdx # CX/DX. The spec I have read movw %ax, %cx # seems to indicate AX/BX movw %bx, %dx # are more reasonable anyway... e801usecxdx: andl $0xffff, %edx # clear sign extend shll $6, %edx # and go from 64k to 1k chunks andl $0xffff, %ecx # clear sign extend addl %ecx, %edx cmpl %cs:highmem_size, %edx # store extended mem size jl mem88 # if it's bigger than movl %edx, %cs:highmem_size # what we already have # Ye Olde Traditional Methode. Returns the memory size (up to 16mb or # 64mb, depending on the bios) in ax. mem88: movb $0x88, %ah int $0x15 andl $0xffff, %eax # clear sign extend cmpl %cs:highmem_size, %eax # store extended mem size jl have_memsize # if it's bigger than movl %eax, %cs:highmem_size # what we already have have_memsize: /* Culled: HDD probes, APM, speedstep */ # Now we want to move to protected mode ... cmpw $0, %cs:realmode_swtch jz rmodeswtch_normal lcall *%cs:realmode_swtch jmp rmodeswtch_end rmodeswtch_normal: pushw %cs call default_switch rmodeswtch_end: /* Culled: code to take the 32bit entry address from the loader */ /* Culled: code to relocate non-bzImage kernels */ # then we load the segment descriptors movw %cs, %ax # aka SETUPSEG movw %ax, %ds # Check whether we need to be downward compatible with version <=201 cmpl $0, cmd_line_ptr jne end_move_self # loader uses version >=202 features cmpb $0x20, type_of_loader je end_move_self # bootsect loader, we know of it # Boot loader doesnt support boot protocol version 2.02. # If we have our code not at 0x90000, we need to move it there now. # We also then need to move the params behind it (commandline) # Because we would overwrite the code on the current IP, we move # it in two steps, jumping high after the first one. movw %cs, %ax cmpw $SETUPSEG, %ax je end_move_self cli # make sure we really have # interrupts disabled ! # because after this the stack # should not be used subw $DELTA_INITSEG, %ax # aka INITSEG movw %ss, %dx cmpw %ax, %dx jb move_self_1 addw $INITSEG, %dx subw %ax, %dx # this will go into %ss after # the move move_self_1: movw %ax, %ds movw $INITSEG, %ax # real INITSEG movw %ax, %es movw %cs:setup_move_size, %cx std # we have to move up, so we use # direction down because the # areas may overlap movw %cx, %di decw %di movw %di, %si subw $move_self_here+0x200, %cx rep movsb ljmp $SETUPSEG, $move_self_here move_self_here: movw $move_self_here+0x200, %cx rep movsb movw $SETUPSEG, %ax movw %ax, %ds movw %dx, %ss end_move_self: # now we are at the right place # # Enable A20. This is at the very best an annoying procedure. # A20 code ported from SYSLINUX 1.52-1.63 by H. Peter Anvin. # AMD Elan bug fix by Robert Schwebel. # #if defined(CONFIG_X86_ELAN) movb $0x02, %al # alternate A20 gate outb %al, $0x92 # this works on SC410/SC520 a20_elan_wait: call a20_test jz a20_elan_wait jmp a20_done #endif A20_TEST_LOOPS = 32 # Iterations per wait A20_ENABLE_LOOPS = 255 # Total loops to try #ifndef CONFIG_X86_VOYAGER a20_try_loop: # First, see if we are on a system with no A20 gate. a20_none: call a20_test jnz a20_done # Next, try the BIOS (INT 0x15, AX=0x2401) a20_bios: movw $0x2401, %ax pushfl # Be paranoid about flags int $0x15 popfl call a20_test jnz a20_done # Try enabling A20 through the keyboard controller #endif /* CONFIG_X86_VOYAGER */ a20_kbc: call empty_8042 #ifndef CONFIG_X86_VOYAGER call a20_test # Just in case the BIOS worked jnz a20_done # but had a delayed reaction. #endif movb $0xD1, %al # command write outb %al, $0x64 call empty_8042 movb $0xDF, %al # A20 on outb %al, $0x60 call empty_8042 #ifndef CONFIG_X86_VOYAGER # Wait until a20 really *is* enabled; it can take a fair amount of # time on certain systems; Toshiba Tecras are known to have this # problem. a20_kbc_wait: xorw %cx, %cx a20_kbc_wait_loop: call a20_test jnz a20_done loop a20_kbc_wait_loop # Final attempt: use "configuration port A" a20_fast: inb $0x92, %al # Configuration Port A orb $0x02, %al # "fast A20" version andb $0xFE, %al # don't accidentally reset outb %al, $0x92 # Wait for configuration port A to take effect a20_fast_wait: xorw %cx, %cx a20_fast_wait_loop: call a20_test jnz a20_done loop a20_fast_wait_loop # A20 is still not responding. Try frobbing it again. # decb (a20_tries) jnz a20_try_loop movw $a20_err_msg, %si call prtstr a20_die: hlt jmp a20_die a20_tries: .byte A20_ENABLE_LOOPS a20_err_msg: .ascii "linux: fatal error: A20 gate not responding!" .byte 13, 10, 0 # If we get here, all is good a20_done: #endif /* CONFIG_X86_VOYAGER */ /* Another print, to show protected mode and A20 are OK */ jmp mb_hello_mess2_end mb_hello_mess2: .string "pack " mb_hello_mess2_end: lea mb_hello_mess2, %si call prtstr # set up gdt and idt /* lidt idt_48 # load idt with 0,0 */ /* Multiboot kernels must set up their own IDT: leave this for now, * so we can print diagnostics */ xorl %eax, %eax # Compute gdt_base movw %ds, %ax # (Convert %ds:gdt to a linear ptr) shll $4, %eax addl $gdt, %eax movl %eax, (gdt_48+2) lgdt gdt_48 # load gdt with whatever is # appropriate # make sure any possible coprocessor is properly reset.. xorw %ax, %ax outb %al, $0xf0 call delay outb %al, $0xf1 call delay # well, that went ok, I hope. Now we mask all interrupts - the rest # is done in init_IRQ(). movb $0xFF, %al # mask all interrupts for now outb %al, $0xA1 call delay movb $0xFB, %al # mask all irq's but irq2 which outb %al, $0x21 # is cascaded # Well, that certainly wasn't fun :-(. Hopefully it works, and we don't # need no steenking BIOS anyway (except for the initial loading :-). # The BIOS-routine wants lots of unnecessary data, and it's less # "interesting" anyway. This is how REAL programmers do it. /* Tailor the jump below so the target is the 32bit trampoline code */ xorl %eax, %eax # Calculate movw %cs, %ax # the linear shll $4, %eax # address of addl $trampoline32, %eax # %cs:trampoline32 movl %eax, %cs:code32 # Stick it into the jmpi /* Load a 32-bit pointer to the entry address into %ecx */ xorl %ecx, %ecx # Calculate movw %cs, %cx # the linear shll $4, %ecx # address of addl $entry_address, %ecx # %cs:entry_address # Well, now's the time to actually move into protected mode. lea mb_ready_mess, %si call prtstr /* May as well load this IDT now */ lidt idt_48 xorl %eax, %eax movw $1, %ax # protected mode (PE) bit lmsw %ax # This is it! jmp flush_instr flush_instr: /* Set up segment registers */ movw $__BOOT_DS, %dx movw %dx, %ds movw %dx, %es movw %dx, %fs movw %dx, %gs movw %dx, %ss /* Trampoline expects this in %eax */ movl %ecx, %eax /* Jump to the 32-bit trampoline */ # NOTE: For high loaded big kernels we need a # jmpi 0x100000,__BOOT_CS # # but we yet haven't reloaded the CS register, so the default size # of the target offset still is 16 bit. # However, using an operand prefix (0x66), the CPU will properly # take our 48 bit far pointer. (INTeL 80386 Programmer's Reference # Manual, Mixing 16-bit and 32-bit code, page 16-6) .byte 0x66, 0xea # prefix + jmpi-opcode code32: .long 0x1000 # will be set to trampoline32 # by code above. .word __BOOT_CS # Here's a bunch of information about your current kernel.. kernel_version: .string "mbootpack changeling bzImage" mb_ready_mess: .ascii MBOOTPACK_VERSION_STRING .ascii "\r\n" .byte 0 # This is the default real mode switch routine. # to be called just before protected mode transition default_switch: cli # no interrupts allowed ! movb $0x80, %al # disable NMI for bootup # sequence outb %al, $0x70 lret #ifndef CONFIG_X86_VOYAGER # This routine tests whether or not A20 is enabled. If so, it # exits with zf = 0. # # The memory address used, 0x200, is the int $0x80 vector, which # should be safe. A20_TEST_ADDR = 4*0x80 a20_test: pushw %cx pushw %ax xorw %cx, %cx movw %cx, %fs # Low memory decw %cx movw %cx, %gs # High memory area movw $A20_TEST_LOOPS, %cx movw %fs:(A20_TEST_ADDR), %ax pushw %ax a20_test_wait: incw %ax movw %ax, %fs:(A20_TEST_ADDR) call delay # Serialize and make delay constant cmpw %gs:(A20_TEST_ADDR+0x10), %ax loope a20_test_wait popw %fs:(A20_TEST_ADDR) popw %ax popw %cx ret #endif /* CONFIG_X86_VOYAGER */ # This routine checks that the keyboard command queue is empty # (after emptying the output buffers) # # Some machines have delusions that the keyboard buffer is always full # with no keyboard attached... # # If there is no keyboard controller, we will usually get 0xff # to all the reads. With each IO taking a microsecond and # a timeout of 100,000 iterations, this can take about half a # second ("delay" == outb to port 0x80). That should be ok, # and should also be plenty of time for a real keyboard controller # to empty. # empty_8042: pushl %ecx movl $100000, %ecx empty_8042_loop: decl %ecx jz empty_8042_end_loop call delay inb $0x64, %al # 8042 status port testb $1, %al # output buffer? jz no_output call delay inb $0x60, %al # read it jmp empty_8042_loop no_output: testb $2, %al # is input buffer full? jnz empty_8042_loop # yes - loop empty_8042_end_loop: popl %ecx ret # Read the cmos clock. Return the seconds in al gettime: pushw %cx movb $0x02, %ah int $0x1a movb %dh, %al # %dh contains the seconds andb $0x0f, %al movb %dh, %ah movb $0x04, %cl shrb %cl, %ah aad popw %cx ret # Delay is needed after doing I/O delay: outb %al,$0x80 ret # Descriptor tables # # NOTE: The intel manual says gdt should be sixteen bytes aligned for # efficiency reasons. However, there are machines which are known not # to boot with misaligned GDTs, so alter this at your peril! If you alter # GDT_ENTRY_BOOT_CS (in asm/segment.h) remember to leave at least two # empty GDT entries (one for NULL and one reserved). # # NOTE: On some CPUs, the GDT must be 8 byte aligned. This is # true for the Voyager Quad CPU card which will not boot without # This directive. 16 byte aligment is recommended by intel. # /* The boot-time code segment is set at the jmpi above */ /* Dont change this without checking everything still matches */ .align 16 gdt: .fill GDT_ENTRY_BOOT_CS,8,0 .word 0xFFFF # 4Gb - (0x100000*0x1000 = 4Gb) .word 0 # base address = 0 .word 0x9A00 # code read/exec .word 0x00CF # granularity = 4096, 386 # (+5th nibble of limit) .word 0xFFFF # 4Gb - (0x100000*0x1000 = 4Gb) .word 0 # base address = 0 .word 0x9200 # data read/write .word 0x00CF # granularity = 4096, 386 # (+5th nibble of limit) gdt_end: .align 4 .word 0 # alignment byte idt_48: .word 0 # idt limit = 0 .word 0, 0 # idt base = 0L .word 0 # alignment byte gdt_48: .word gdt_end - gdt - 1 # gdt limit .word 0, 0 # gdt base (filled in later) # Include video setup & detection code /* #include "video.S" */ .code32 trampoline32: /* Here, %eax = 32-bit pointer to entry_address */ /* Check if the bootloader gave us a (non-empty) command line */ movl -8(%eax), %ebx # cmd_line_ptr cmpl $0, %ebx je no_cmd_line cmpb $0, 0(%ebx) je no_cmd_line /* Find the MBI command line */ movl %eax, %ecx # &entry_address addl $(begtext-entry_address), %ecx # --> start of setup subl $0x9200, %ecx # --> reloc offset movl %ecx, %esi # (copy offset) movl %ecx, %ebx # (copy offset) addl 4(%eax), %ecx # --> current addr of MBI addl 16(%ecx), %ebx # --> cur. addr of MB cmdline /* Overwrite the built-in MBI kernel command line */ movl -8(%eax), %ecx movl $0, %edi /* Give the kernel a 'self' word, that linux doesn't get */ movw $0x202E, 0(%ebx) # '. ' addl $0x2, %ebx cmd_line_copy: movb (%ecx, %edi), %dl movb %dl, (%ebx, %edi) inc %edi cmp $CMD_LINE_SPACE-3, %edi je cmd_line_copy_end cmpb $0x0, %dl jne cmd_line_copy cmd_line_copy_end: movb $0x0, (%ebx, %edi) subl $0x2, %ebx /* Look for '--' in the kernel command line */ cmd_line_scan: inc %ebx cmpb $0x0, 0(%ebx) je no_cmd_line cmpl $0x202D2D20, 0(%ebx) # ' -- ' jne cmd_line_scan /* Found it: terminate kernel's command line */ movb $0x0, 0(%ebx) inc %ebx /* Relocate address to where it will be moved to */ subl %esi, %ebx /* Is there a module 0? */ movl %esi, %ecx # Reloc offset addl 4(%eax), %ecx # --> current addr of MBI cmpl $0x0, 20(%ecx) # (check module count) je no_cmd_line /* Overwrite module 0's command line */ movl %esi, %edx # Reloc offset addl 24(%ecx), %edx # --> cur. add. of Module 0 movl %ebx, 8(%edx) # --> blat mod. 0's cmdline no_cmd_line: /* Relocate the MBI from after the setup code to its proper home * between the MBI pointer and 0xa000 */ movl %eax, %ecx # &entry_address addl $(begtext-entry_address), %ecx # --> start of setup subl $0x9200, %ecx # --> reloc offset addl 4(%eax), %ecx # --> current addr of MBI movl $0xa000, %ebx # End of MBI subl 4(%eax), %ebx # --> size of MBI movl %ebx, %edi movl 4(%eax), %ebx # Destination of MBI mbi_copy: dec %edi movb (%ecx, %edi), %dl movb %dl, (%ebx, %edi) cmp $0x0, %edi jne mbi_copy /* Copy memory size into MBI structure */ movl 4(%eax), %ebx # MBI pointer movl 8(%eax), %ecx # highmem_size movl %ecx, 8(%ebx) # --> mbi.mem_upper movl $0x280, %ecx movl %ecx, 4(%ebx) # --> mbi.mem_lower /* Set the MB_INFO_MEMORY bit */ orl $1, 0(%ebx) /* Recover the MBI pointer into %ebx */ movl 4(%eax), %ebx # MBI pointer /* Extract the load address into %ecx */ movl 0(%eax), %ecx /* Let the kernel know we're a multiboot loader */ movl $0x2BADB002, %eax /* Jump to the kernel address supplied */ jmp *%ecx # Setup signature -- must be last setup_sig1: .word SIG1 setup_sig2: .word SIG2 # After this point, there is some free space which is used by the video mode # handling code to store the temporary mode table (not used by the kernel). modelist: .text endtext: .data enddata: .bss endbss: