xref: /titanic_41/usr/src/uts/i86pc/boot/boot_gdt.s (revision fc7a376ec44146b66b5d6bc4ed92ba311773e202)
1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22/*
23 * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27
28#if defined(__lint)
29#pragma pack(1)
30struct {
31	uint16_t limit_low;
32	uint16_t base_low;
33	uint8_t base_middle;
34	uint8_t attr;
35	uint8_t attr_and_limit;
36	uint8_t base_high;
37} global_descriptor_table[8];
38struct {
39	uint16_t limit;	/* sizeof (global_descriptor_table) - 1 */
40	void     *base;	/* &global_descriptor_table */
41} gdt_info;
42#pragma pack()
43
44#else	/* __lint */
45
46	.align 16
47	.data
48	/*
49	 * This must remain in sync with the entries in intel/sys/gdt.h; in
50	 * particular kmdb uses B64CODE_SEL or B32CODE_SEL in perpetuity for
51	 * its IDT entries (they're copied to the kernel's GDT in init_idt()).
52	 */
53
54global_descriptor_table:
55	.long   0
56	.long   0
57
58	/* GDT_B32DATA: 32 bit flat data descriptor */
59	.value  0xFFFF	/* segment limit 0..15 */
60	.value  0x0000	/* segment base 0..15 */
61	.byte   0x0	/* segment base 16..23 */
62	.byte   0x92	/* P = 1, read/write data */
63	.byte   0xCF	/* G=1, B=1, Limit (16..19)=1111 */
64	.byte   0x0	/* segment base 24..32 */
65
66	/* GDT_B32CODE 32 bit flat code descriptor */
67	.value  0xFFFF	/* segment limit 0..15 */
68	.value  0x0000	/* segment base 0..15 */
69	.byte   0x0	/* segment base 16..23 */
70	.byte   0x9A	/* P=1, code, exec, readable */
71	.byte   0xCF	/* G=1, D=1, Limit (16..19)=1111 */
72	.byte   0x0	/* segment base 24..32 */
73
74	/*
75	 * GDT_B16CODE 16 bit code descriptor for doing BIOS calls
76	 */
77	.value  0xFFFF	/* segment limit 0..15 */
78	.value  0x0000	/* segment base 0..15 */
79	.byte   0x0	/* segment base 16..23 */
80	.byte   0x9A	/* P=1, code, exec, readable */
81	.byte   0x0F	/* G=0, D=0, Limit (16..19)=1111 */
82	.byte   0x0	/* segment base 24..32 */
83
84	/*
85	 * GDT_B16DATA 16 bit data descriptor for doing BIOS calls
86	 */
87	.value  0xFFFF	/* segment limit 0..15 */
88	.value  0x0000	/* segment base 0..15 */
89	.byte   0x0	/* segment base 16..23 */
90	.byte   0x92	/* P = 1, read/write data */
91	.byte   0x4F	/* G=0, D=1, Limit (16..19)=1111 */
92	.byte   0x0	/* segment base 24..32 */
93
94	/* GDT_B64CODE: 64 bit flat code descriptor - only L bit has meaning */
95	.value  0xFFFF	/* segment limit 0..15 */
96	.value  0x0000	/* segment base 0..15 */
97	.byte   0x0	/* segment base 16..23 */
98	.byte   0x9A	/* P=1, code, exec, readable */
99	.byte   0xAF	/* G=1, D=0, L=1, Limit (16..19)=1111 */
100	.byte   0x0	/* segment base 24..32 */
101
102	/*
103	 * unused
104	 */
105	.long	0
106	.long	0
107
108        /*
109         * GDT_BGSTMP -- an entry for kmdb to use during boot
110         * the fast reboot code uses this entry for memory copies, too.
111         */
112	.value  0x0001	/* segment limit 0..15 */
113
114	.globl fake_cpu_gdt_base_0_15
115fake_cpu_gdt_base_0_15:
116
117	.value  0x0000	/* segment base 0..15 */
118
119	.globl fake_cpu_gdt_base_16_23
120fake_cpu_gdt_base_16_23:
121	.byte   0x0	/* segment base 16..23 */
122	.byte   0x9A	/* P=1, code, exec, readable */
123	.byte   0xC0	/* G=1, D=1, Limit (16..19)=0000 */
124
125	.globl fake_cpu_gdt_base_24_31
126fake_cpu_gdt_base_24_31:
127	.byte   0x0	/* segment base 24..32 */
128
129/	.long	0
130/	.long	0
131
132gdt_info:
133	.value	gdt_info - global_descriptor_table - 1
134	.long	global_descriptor_table
135	.long   0		/* needed for 64 bit */
136
137fake_cpu:
138	.4byte 0
139	.4byte 0
140	.4byte 0
141	.globl fake_cpu_ptr
142fake_cpu_ptr:
143	.4byte 0
144	.skip 0x6c0, 0
145
146#endif	/* __lint */
147