x86bios.c revision 197475 
1/*-
2 * Written by paradox <ddkprog@yahoo.com>
3 * Public domain.
4 */
5
6#include <sys/cdefs.h>
7__FBSDID("$FreeBSD: head/sys/compat/x86bios/x86bios.c 197475 2009-09-24 22:42:35Z jkim $");
8
9#include "opt_x86bios.h"
10
11#include <sys/param.h>
12#include <sys/kernel.h>
13#include <sys/lock.h>
14#include <sys/module.h>
15#include <sys/mutex.h>
16
17#include <vm/vm.h>
18#include <vm/pmap.h>
19
20#include <machine/cpufunc.h>
21
22#include <contrib/x86emu/x86emu.h>
23#include <contrib/x86emu/x86emu_regs.h>
24#include <compat/x86bios/x86bios.h>
25
26u_char *pbiosMem = NULL;
27static u_char *pbiosStack = NULL;
28
29int busySegMap[5];
30
31static struct x86emu x86bios_emu;
32
33static struct mtx x86bios_lock;
34
35static uint8_t
36x86bios_emu_inb(struct x86emu *emu, uint16_t port)
37{
38
39	if (port == 0xb2) /* APM scratch register */
40		return (0);
41	if (port >= 0x80 && port < 0x88) /* POST status register */
42		return (0);
43	return (inb(port));
44}
45
46static uint16_t
47x86bios_emu_inw(struct x86emu *emu, uint16_t port)
48{
49
50	if (port >= 0x80 && port < 0x88) /* POST status register */
51		return (0);
52	return (inw(port));
53}
54
55static uint32_t
56x86bios_emu_inl(struct x86emu *emu, uint16_t port)
57{
58
59	if (port >= 0x80 && port < 0x88) /* POST status register */
60		return (0);
61	return (inl(port));
62}
63
64static void
65x86bios_emu_outb(struct x86emu *emu, uint16_t port, uint8_t val)
66{
67
68	if (port == 0xb2) /* APM scratch register */
69		return;
70	if (port >= 0x80 && port < 0x88) /* POST status register */
71		return;
72	outb(port, val);
73}
74
75static void
76x86bios_emu_outw(struct x86emu *emu, uint16_t port, uint16_t val)
77{
78
79	if (port >= 0x80 && port < 0x88) /* POST status register */
80		return;
81	outw(port, val);
82}
83
84static void
85x86bios_emu_outl(struct x86emu *emu, uint16_t port, uint32_t val)
86{
87
88	if (port >= 0x80 && port < 0x88) /* POST status register */
89		return;
90	outl(port, val);
91}
92
93void
94x86bios_intr(struct x86regs *regs, int intno)
95{
96
97	if (intno < 0 || intno > 255)
98		return;
99
100	if (bootverbose)
101		printf("Calling real mode int 0x%x "
102		    "(ax=0x%04x bx=0x%04x cx=0x%04x dx=0x%04x)\n",
103		    intno, regs->R_AX, regs->R_BX, regs->R_CX, regs->R_DX);
104
105	mtx_lock_spin(&x86bios_lock);
106
107	memcpy(&x86bios_emu.x86, regs, sizeof(*regs));
108	x86emu_exec_intr(&x86bios_emu, intno);
109	memcpy(regs, &x86bios_emu.x86, sizeof(*regs));
110
111	mtx_unlock_spin(&x86bios_lock);
112
113	if (bootverbose)
114		printf("Exiting real mode int 0x%x "
115		    "(ax=0x%04x bx=0x%04x cx=0x%04x dx=0x%04x)\n",
116		    intno, regs->R_AX, regs->R_BX, regs->R_CX, regs->R_DX);
117}
118
119void *
120x86bios_offset(uint32_t offs)
121{
122
123	return (pbiosMem + offs);
124}
125
126static void
127x86bios_init(void *arg __unused)
128{
129	int offs;
130
131	mtx_init(&x86bios_lock, "x86bios lock", NULL, MTX_SPIN);
132
133	/* Can pbiosMem be NULL here? */
134	pbiosMem = pmap_mapbios(0x0, MAPPED_MEMORY_SIZE);
135
136	memset(&x86bios_emu, 0, sizeof(x86bios_emu));
137	x86emu_init_default(&x86bios_emu);
138
139	x86bios_emu.emu_inb = x86bios_emu_inb;
140	x86bios_emu.emu_inw = x86bios_emu_inw;
141	x86bios_emu.emu_inl = x86bios_emu_inl;
142	x86bios_emu.emu_outb = x86bios_emu_outb;
143	x86bios_emu.emu_outw = x86bios_emu_outw;
144	x86bios_emu.emu_outl = x86bios_emu_outl;
145
146	x86bios_emu.mem_base = (char *)pbiosMem;
147	x86bios_emu.mem_size = 1024 * 1024;
148
149	memset(busySegMap, 0, sizeof(busySegMap));
150
151	pbiosStack = x86bios_alloc(1, &offs);
152}
153
154static void
155x86bios_uninit(void *arg __unused)
156{
157
158	x86bios_free(pbiosStack, 1);
159
160	if (pbiosMem)
161		pmap_unmapdev((vm_offset_t)pbiosMem,
162		    MAPPED_MEMORY_SIZE);
163
164	mtx_destroy(&x86bios_lock);
165}
166
167static int
168x86bios_modevent(module_t mod __unused, int type, void *data __unused)
169{
170	int err = 0;
171
172	switch (type) {
173	case MOD_LOAD:
174		x86bios_init(NULL);
175		break;
176	case MOD_UNLOAD:
177		x86bios_uninit(NULL);
178		break;
179	default:
180		err = ENOTSUP;
181		break;
182	}
183
184	return (err);
185}
186
187static moduledata_t x86bios_mod = {
188	"x86bios",
189	x86bios_modevent,
190	NULL,
191};
192
193DECLARE_MODULE(x86bios, x86bios_mod, SI_SUB_CPU, SI_ORDER_ANY);
194MODULE_VERSION(x86bios, 1);
195