xref: /haiku/src/system/boot/platform/atari_m68k/start.cpp (revision c90684742e7361651849be4116d0e5de3a817194)
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 "toscalls.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 	//smp_init_other_cpus();
78 	//serial_cleanup();
79 	mmu_init_for_kernel();
80 	//smp_boot_other_cpus();
81 
82 #warning M68K: stop ints
83 
84 	dprintf("kernel entry at %lx\n",
85 		gKernelArgs.kernel_image.elf_header.e_entry);
86 
87 	asm volatile (
88 		"move.l	%0,%%sp;	"			// move stack out of way
89 		: : "m" (stackTop));
90 
91 	asm volatile (
92 		"or	#0x0700,%%sr; " : : );		// disable interrupts
93 
94 	asm volatile (
95 		"move.l  #0x0,-(%%sp); "		// we're the BSP cpu (0)
96 		"move.l 	%0,-(%%sp);	"		// kernel args
97 		"move.l 	#0x0,-(%%sp);"		// dummy retval for call to main
98 		"move.l 	%1,-(%%sp);	"		// this is the start address
99 		"rts;		"					// jump.
100 		: : "g" (args), "g" (gKernelArgs.kernel_image.elf_header.e_entry));
101 
102 	// Huston, we have a problem!
103 
104 	asm volatile (
105 		"and	#0xf8ff,%%sr; " : : );		// reenable interrupts
106 
107 	panic("kernel returned!\n");
108 
109 }
110 
111 
112 extern "C" void
113 platform_exit(void)
114 {
115 	// Terminate
116 	// TODO: Puntaes() instead ?
117 	Pterm0();
118 }
119 
120 
121 extern "C" void
122 _start(void)
123 {
124 	stage2_args args;
125 	Bconout(DEV_CON, 'H');
126 
127 	//asm("cld");			// Ain't nothing but a GCC thang.
128 	//asm("fninit");		// initialize floating point unit
129 
130 	clear_bss();
131 	Bconout(DEV_CON, 'A');
132 	call_ctors();
133 		// call C++ constructors before doing anything else
134 	Bconout(DEV_CON, 'I');
135 
136 	args.heap_size = HEAP_SIZE;
137 	args.arguments = NULL;
138 
139 	// so we can dprintf
140 	init_nat_features();
141 
142 	//serial_init();
143 	Bconout(DEV_CON, 'K');
144 	console_init();
145 	Bconout(DEV_CON, 'U');
146 	dprintf("membot   = %p\n", (void*)*TOSVAR_membot);
147 	dprintf("memtop   = %p\n", (void*)*TOSVAR_memtop);
148 	dprintf("v_bas_ad = %p\n", *TOSVAR_v_bas_ad);
149 	dprintf("phystop  = %p\n", (void*)*TOSVARphystop);
150 	dprintf("ramtop   = %p\n", (void*)*TOSVARramtop);
151 	cpu_init();
152 	mmu_init();
153 
154 	// wait a bit to give the user the opportunity to press a key
155 	spin(750000);
156 
157 	// reading the keyboard doesn't seem to work in graphics mode (maybe a bochs problem)
158 	sBootOptions = check_for_boot_keys();
159 	//if (sBootOptions & BOOT_OPTION_DEBUG_OUTPUT)
160 		//serial_enable();
161 
162 	//apm_init();
163 	//smp_init();
164 	main(&args);
165 }
166