1 | #
|
---|
2 | # Copyright (c) 2005 Martin Decky
|
---|
3 | # All rights reserved.
|
---|
4 | #
|
---|
5 | # Redistribution and use in source and binary forms, with or without
|
---|
6 | # modification, are permitted provided that the following conditions
|
---|
7 | # are met:
|
---|
8 | #
|
---|
9 | # - Redistributions of source code must retain the above copyright
|
---|
10 | # notice, this list of conditions and the following disclaimer.
|
---|
11 | # - Redistributions in binary form must reproduce the above copyright
|
---|
12 | # notice, this list of conditions and the following disclaimer in the
|
---|
13 | # documentation and/or other materials provided with the distribution.
|
---|
14 | # - The name of the author may not be used to endorse or promote products
|
---|
15 | # derived from this software without specific prior written permission.
|
---|
16 | #
|
---|
17 | # THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
|
---|
18 | # IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
---|
19 | # OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
|
---|
20 | # IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
|
---|
21 | # INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
|
---|
22 | # NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
---|
23 | # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
---|
24 | # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
---|
25 | # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
|
---|
26 | # THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
---|
27 | #
|
---|
28 |
|
---|
29 | #include <abi/asmtool.h>
|
---|
30 |
|
---|
31 | INTEL_CPUID_STANDARD = 1
|
---|
32 | INTEL_SEP = 11
|
---|
33 |
|
---|
34 | .text
|
---|
35 |
|
---|
36 | .org 0
|
---|
37 |
|
---|
38 | ## User-space task entry point
|
---|
39 | #
|
---|
40 | # %edi contains the PCB pointer
|
---|
41 | #
|
---|
42 | SYMBOL(_start)
|
---|
43 | mov %ss, %ax
|
---|
44 | mov %ax, %ds
|
---|
45 | mov %ax, %es
|
---|
46 | mov %ax, %fs
|
---|
47 | # Do not set %gs, it contains descriptor that can see TLS
|
---|
48 |
|
---|
49 | #ifndef PROCESSOR_i486
|
---|
50 | # Detect the mechanism used for making syscalls
|
---|
51 | movl $(INTEL_CPUID_STANDARD), %eax
|
---|
52 | cpuid
|
---|
53 | bt $(INTEL_SEP), %edx
|
---|
54 | jnc 0f
|
---|
55 | leal __syscall_fast_func, %eax
|
---|
56 | movl $__syscall_fast, (%eax)
|
---|
57 | 0:
|
---|
58 | #endif
|
---|
59 |
|
---|
60 | #
|
---|
61 | # Create the first stack frame.
|
---|
62 | #
|
---|
63 | pushl $0
|
---|
64 | pushl $0
|
---|
65 | movl %esp, %ebp
|
---|
66 |
|
---|
67 | # Pass the PCB pointer to __c_start as the first argument
|
---|
68 | pushl %edi
|
---|
69 | call __c_start
|
---|