xref: /haiku/src/system/boot/platform/amiga_m68k/start.cpp (revision 3a2a3367dc9bec2a5fbcd4ac849da6ac65e74e79)
1 /*
2  * Copyright 2003-2010, Axel Dörfler, axeld@pinc-software.de.
3  * Copyright 2008, François Revol, revol@free.fr. All rights reserved.
4  * Distributed under the terms of the MIT License.
5  */
6 
7 
8 #include <KernelExport.h>
9 #include <boot/platform.h>
10 #include <boot/heap.h>
11 #include <boot/stage2.h>
12 #include <arch/cpu.h>
13 
14 #include <string.h>
15 
16 #include "console.h"
17 #include "cpu.h"
18 #include "mmu.h"
19 #include "keyboard.h"
20 #include "rom_calls.h"
21 
22 
23 #define HEAP_SIZE 65536
24 
25 // GCC defined globals
26 extern void (*__ctor_list)(void);
27 extern void (*__ctor_end)(void);
28 extern uint8 __bss_start;
29 extern uint8 _end;
30 
31 extern "C" int main(stage2_args *args);
32 extern "C" void _start(void);
33 
34 
35 static uint32 sBootOptions;
36 
37 
38 static void
39 clear_bss(void)
40 {
41 	memset(&__bss_start, 0, &_end - &__bss_start);
42 }
43 
44 
45 static void
46 call_ctors(void)
47 {
48 	void (**f)(void);
49 
50 	for (f = &__ctor_list; f < &__ctor_end; f++) {
51 		(**f)();
52 	}
53 }
54 
55 
56 extern "C" uint32
57 platform_boot_options(void)
58 {
59 #if 0
60 	if (!gKernelArgs.fb.enabled)
61 		sBootOptions |= check_for_boot_keys();
62 #endif
63 	return sBootOptions;
64 }
65 
66 
67 extern "C" void
68 platform_start_kernel(void)
69 {
70 	static struct kernel_args *args = &gKernelArgs;
71 		// something goes wrong when we pass &gKernelArgs directly
72 		// to the assembler inline below - might be a bug in GCC
73 		// or I don't see something important...
74 	addr_t stackTop
75 		= gKernelArgs.cpu_kstack[0].start + gKernelArgs.cpu_kstack[0].size;
76 
77 	preloaded_elf32_image *image = static_cast<preloaded_elf32_image *>(
78 		gKernelArgs.kernel_image);
79 
80 	//smp_init_other_cpus();
81 	//serial_cleanup();
82 	mmu_init_for_kernel();
83 	//smp_boot_other_cpus();
84 
85 #warning M68K: stop ints
86 
87 	dprintf("kernel entry at %lx\n", image->elf_header.e_entry);
88 
89 	asm volatile (
90 		"move.l	%0,%%sp;	"			// move stack out of way
91 		: : "m" (stackTop));
92 
93 	asm volatile (
94 		"or	#0x0700,%%sr; " : : );		// disable interrupts
95 
96 	asm volatile (
97 		"move.l  #0x0,-(%%sp); "		// we're the BSP cpu (0)
98 		"move.l 	%0,-(%%sp);	"		// kernel args
99 		"move.l 	#0x0,-(%%sp);"		// dummy retval for call to main
100 		"move.l 	%1,-(%%sp);	"		// this is the start address
101 		"rts;		"					// jump.
102 		: : "g" (args), "g" (image->elf_header.e_entry));
103 
104 	// Huston, we have a problem!
105 
106 	asm volatile (
107 		"and	#0xf8ff,%%sr; " : : );		// reenable interrupts
108 
109 	panic("kernel returned!\n");
110 
111 }
112 
113 
114 extern "C" void
115 platform_exit(void)
116 {
117 	ColdReboot();
118 	// Terminate
119 	//TODO
120 	while (true) {}
121 }
122 
123 extern "C" void
124 _start(void)
125 {
126 	stage2_args args;
127 
128 	//asm("cld");			// Ain't nothing but a GCC thang.
129 	//asm("fninit");		// initialize floating point unit
130 
131 	clear_bss();
132 	call_ctors();
133 		// call C++ constructors before doing anything else
134 
135 	args.heap_size = HEAP_SIZE;
136 	args.arguments = NULL;
137 
138 	//serial_init();
139 	console_init();
140 	dprintf("ramtop   = %p\n", NULL);
141 	cpu_init();
142 	mmu_init();
143 
144 	// wait a bit to give the user the opportunity to press a key
145 	spin(750000);
146 
147 	// reading the keyboard doesn't seem to work in graphics mode (maybe a bochs problem)
148 	sBootOptions = check_for_boot_keys();
149 	//if (sBootOptions & BOOT_OPTION_DEBUG_OUTPUT)
150 		//serial_enable();
151 
152 	//apm_init();
153 	//smp_init();
154 	main(&args);
155 }
156