mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-27 07:20:11 +00:00
41bdb6e20c
2001-07-06 Paul Eggert <eggert@twinsun.com> * manual/argp.texi: Remove ignored LGPL copyright notice; it's not appropriate for documentation anyway. * manual/libc-texinfo.sh: "Library General Public License" -> "Lesser General Public License". 2001-07-06 Andreas Jaeger <aj@suse.de> * All files under GPL/LGPL version 2: Place under LGPL version 2.1.
322 lines
8.7 KiB
ArmAsm
322 lines
8.7 KiB
ArmAsm
/* Copyright (C) 1994, 1997 Free Software Foundation, Inc.
|
|
Contributed by Joel Sherrill (jsherril@redstone-emh2.army.mil),
|
|
On-Line Applications Research Corporation.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library 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
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, write to the Free
|
|
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
|
|
02111-1307 USA. */
|
|
|
|
/* entry.s
|
|
*
|
|
* This file contains the entry point for the application.
|
|
* The name of this entry point is compiler dependent.
|
|
* It jumps to the BSP which is responsible for performing
|
|
* all initialization.
|
|
*
|
|
*/
|
|
|
|
.data
|
|
.global _Do_Load_IDT
|
|
.global _Do_Load_GDT
|
|
|
|
.text
|
|
.global start # GNU default entry point
|
|
.global _establish_stack
|
|
|
|
.global _bsp_start
|
|
.global _load_segments
|
|
.global __exit
|
|
|
|
start:
|
|
nop
|
|
cli # DISABLE INTERRUPTS!!!
|
|
#
|
|
# Load the segment registers
|
|
#
|
|
# NOTE: Upon return, gs will contain the segment descriptor for
|
|
# a segment which maps directly to all of physical memory.
|
|
#
|
|
jmp _load_segments # load board dependent segments
|
|
|
|
#
|
|
# Set up the stack
|
|
#
|
|
|
|
_establish_stack:
|
|
|
|
movl $stack_end,%esp # set stack pointer
|
|
movl $stack_end,%ebp # set base pointer
|
|
|
|
#
|
|
# Zero out the BSS segment
|
|
#
|
|
zero_bss:
|
|
cld # make direction flag count up
|
|
movl $_end,%ecx # find end of .bss
|
|
movl $_bss_start,%edi # edi = beginning of .bss
|
|
subl %edi,%ecx # ecx = size of .bss in bytes
|
|
shrl $2,%ecx # size of .bss in longs
|
|
xorl %eax,%eax # value to clear out memory
|
|
repne # while ecx != 0
|
|
stosl # clear a long in the bss
|
|
|
|
#
|
|
# Set the C heap information for malloc
|
|
#
|
|
movl $heap_size,___C_heap_size # set ___C_heap_size
|
|
movl $heap_memory,___C_heap_start # set ___C_heap_start
|
|
|
|
#
|
|
# Copy the Global Descriptor Table to our space
|
|
#
|
|
|
|
sgdt _Original_GDTR # save original GDT
|
|
movzwl _Original_GDTR_limit,%ecx # size of GDT in bytes; limit
|
|
# is 8192 entries * 8 bytes per
|
|
|
|
# make ds:esi point to the original GDT
|
|
|
|
movl _Original_GDTR_base,%esi
|
|
push %ds # save ds
|
|
movw %gs,%ax
|
|
movw %ax,%ds
|
|
|
|
# make es:edi point to the new (our copy) GDT
|
|
movl $_Global_descriptor_table,%edi
|
|
|
|
rep
|
|
movsb # copy the GDT (ds:esi -> es:edi)
|
|
|
|
pop %ds # restore ds
|
|
|
|
# Build and load new contents of GDTR
|
|
movw _Original_GDTR_limit,%ecx # set new limit
|
|
movw %cx,_New_GDTR_limit
|
|
|
|
push $_Global_descriptor_table
|
|
push %es
|
|
call _Logical_to_physical
|
|
addl $6,%esp
|
|
movl %eax,_New_GDTR_base # set new base
|
|
|
|
cmpb $0,_Do_Load_GDT # Should the new GDT be loaded?
|
|
je no_gdt_load # NO, then branch
|
|
lgdt _New_GDTR # load the new GDT
|
|
no_gdt_load:
|
|
|
|
#
|
|
# Copy the Interrupt Descriptor Table to our space
|
|
#
|
|
|
|
sidt _Original_IDTR # save original IDT
|
|
movzwl _Original_IDTR_limit,%ecx # size of IDT in bytes; limit
|
|
# is 256 entries * 8 bytes per
|
|
|
|
|
|
# make ds:esi point to the original IDT
|
|
movl _Original_IDTR_base,%esi
|
|
|
|
push %ds # save ds
|
|
movw %gs,%ax
|
|
movw %ax,%ds
|
|
|
|
# make es:edi point to the new (our copy) IDT
|
|
movl $_Interrupt_descriptor_table,%edi
|
|
|
|
rep
|
|
movsb # copy the IDT (ds:esi -> es:edi)
|
|
pop %ds # restore ds
|
|
|
|
# Build and load new contents of IDTR
|
|
movw _Original_IDTR_limit,%ecx # set new limit
|
|
movw %cx,_New_IDTR_limit
|
|
|
|
push $_Interrupt_descriptor_table
|
|
push %es
|
|
call _Logical_to_physical
|
|
addl $6,%esp
|
|
movl %eax,_New_IDTR_base # set new base
|
|
|
|
cmpb $0,_Do_Load_IDT # Should the new IDT be loaded?
|
|
je no_idt_load # NO, then branch
|
|
lidt _New_IDTR # load the new IDT
|
|
no_idt_load:
|
|
|
|
#
|
|
# Initialize the i387.
|
|
#
|
|
# Using the NO WAIT form of the instruction insures that if
|
|
# it is not present the board will not lock up or get an
|
|
# exception.
|
|
#
|
|
|
|
fninit # MUST USE NO-WAIT FORM
|
|
|
|
call __Board_Initialize # initialize the board
|
|
|
|
pushl $0 # envp = NULL
|
|
pushl $0 # argv = NULL
|
|
pushl $0 # argc = NULL
|
|
call ___libc_init # initialize the library and
|
|
# call main
|
|
addl $12,%esp
|
|
|
|
pushl $0 # argc = NULL
|
|
call __exit # call the Board specific exit
|
|
addl $4,%esp
|
|
|
|
#
|
|
# Clean up
|
|
#
|
|
|
|
|
|
.global _Bsp_cleanup
|
|
|
|
.global _return_to_monitor
|
|
|
|
_Bsp_cleanup:
|
|
cmpb $0,_Do_Load_IDT # Was the new IDT loaded?
|
|
je no_idt_restore # NO, then branch
|
|
lidt _Original_IDTR # restore the new IDT
|
|
no_idt_restore:
|
|
|
|
cmpb $0,_Do_Load_GDT # Was the new GDT loaded?
|
|
je no_gdt_restore # NO, then branch
|
|
lgdt _Original_GDTR # restore the new GDT
|
|
no_gdt_restore:
|
|
jmp _return_to_monitor
|
|
|
|
#
|
|
# void *Logical_to_physical(
|
|
# rtems_unsigned16 segment,
|
|
# void *address
|
|
# );
|
|
#
|
|
# Returns thirty-two bit physical address for segment:address.
|
|
#
|
|
|
|
.global _Logical_to_physical
|
|
|
|
.set SEGMENT_ARG, 4
|
|
.set ADDRESS_ARG, 8
|
|
|
|
_Logical_to_physical:
|
|
|
|
xorl %eax,%eax # clear eax
|
|
movzwl SEGMENT_ARG(%esp),%ecx # ecx = segment value
|
|
movl $_Global_descriptor_table,%edx # edx = address of our GDT
|
|
addl %ecx,%edx # edx = address of desired entry
|
|
movb 7(%edx),%ah # ah = base 31:24
|
|
movb 4(%edx),%al # al = base 23:16
|
|
shll $16,%eax # move ax into correct bits
|
|
movw 2(%edx),%ax # ax = base 0:15
|
|
movl ADDRESS_ARG(%esp),%ecx # ecx = address to convert
|
|
addl %eax,%ecx # ecx = physical address equivalent
|
|
movl %ecx,%eax # eax = ecx
|
|
ret
|
|
|
|
#
|
|
# void *Physical_to_logical(
|
|
# rtems_unsigned16 segment,
|
|
# void *address
|
|
# );
|
|
#
|
|
# Returns thirty-two bit physical address for segment:address.
|
|
#
|
|
|
|
.global _Physical_to_logical
|
|
|
|
#.set SEGMENT_ARG, 4
|
|
#.set ADDRESS_ARG, 8 -- use sets from above
|
|
|
|
_Physical_to_logical:
|
|
|
|
xorl %eax,%eax # clear eax
|
|
movzwl SEGMENT_ARG(%esp),%ecx # ecx = segment value
|
|
movl $_Global_descriptor_table,%edx # edx = address of our GDT
|
|
addl %ecx,%edx # edx = address of desired entry
|
|
movb 7(%edx),%ah # ah = base 31:24
|
|
movb 4(%edx),%al # al = base 23:16
|
|
shll $16,%eax # move ax into correct bits
|
|
movw 2(%edx),%ax # ax = base 0:15
|
|
movl ADDRESS_ARG(%esp),%ecx # ecx = address to convert
|
|
subl %eax,%ecx # ecx = logical address equivalent
|
|
movl %ecx,%eax # eax = ecx
|
|
ret
|
|
|
|
|
|
/*
|
|
* Data Declarations. Start with a macro which helps declare space.
|
|
*/
|
|
|
|
.bss
|
|
|
|
#define DECLARE_SPACE(_name,_space,_align) \
|
|
.globl _name ; \
|
|
.align _align ; \
|
|
_name##: .space _space
|
|
|
|
#define DECLARE_LABEL(_name) \
|
|
.globl _name ; \
|
|
_name##:
|
|
|
|
#define DECLARE_PTR(_name) DECLARE_SPACE(_name,4,2)
|
|
#define DECLARE_U32(_name) DECLARE_SPACE(_name,4,2)
|
|
#define DECLARE_U16(_name) DECLARE_SPACE(_name,2,1)
|
|
|
|
/*
|
|
* Require environment stuff
|
|
*/
|
|
|
|
DECLARE_LABEL(_environ)
|
|
DECLARE_PTR(environ)
|
|
|
|
DECLARE_LABEL(_errno)
|
|
DECLARE_U32(errno)
|
|
|
|
/*
|
|
* Miscellaneous Variables used to restore the CPU state.
|
|
*
|
|
* Start with a macro to declare the space for the contents of
|
|
* a Descriptor Table register.
|
|
*/
|
|
|
|
#define DECLARE_DTR_SPACE(_name) \
|
|
.global _name ; \
|
|
.align 4 ; \
|
|
_name##: ; \
|
|
_name##_limit: .space 2 ; \
|
|
_name##_base: .space 4
|
|
|
|
DECLARE_SPACE(_Interrupt_descriptor_table,256*8,4)
|
|
DECLARE_SPACE(_Global_descriptor_table,8192*8,4)
|
|
|
|
DECLARE_DTR_SPACE(_Original_IDTR)
|
|
DECLARE_DTR_SPACE(_New_IDTR)
|
|
DECLARE_DTR_SPACE(_Original_GDTR)
|
|
DECLARE_DTR_SPACE(_New_GDTR)
|
|
|
|
DECLARE_SPACE(_Physical_base_of_ds,4,4)
|
|
DECLARE_SPACE(_Physical_base_of_cs,4,4)
|
|
|
|
/*
|
|
* Stack Size and Space
|
|
*/
|
|
|
|
.set stack_size, 0x20000
|
|
|
|
DECLARE_SPACE(stack_memory,stack_size,4)
|
|
DECLARE_LABEL(stack_end)
|