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 * Copyright 2020 Joyent, Inc. 27 * Copyright 2022 Oxide Computer Company 28 */ 29 30 31/* 32 * The boot GDT must remain in sync with the entries in intel/sys/segments.h; in 33 * particular kmdb uses B64CODE_SEL or B32CODE_SEL in perpetuity for its IDT 34 * entries (they're copied to the kernel's GDT in init_idt()). 35 * 36 * The GDT is effectively an array of user_desc_t entries. 37 */ 38 39 .align 16 40 .data 41 42global_descriptor_table: 43 .long 0 44 .long 0 45 46 /* GDT_B32DATA: 32 bit flat data descriptor */ 47 .value 0xFFFF /* segment limit 0..15 */ 48 .value 0x0000 /* segment base 0..15 */ 49 .byte 0x0 /* segment base 16..23 */ 50 .byte 0x92 /* P = 1, read/write data */ 51 .byte 0xCF /* G=1, B=1, Limit (16..19)=1111 */ 52 .byte 0x0 /* segment base 24..32 */ 53 54 /* GDT_B32CODE 32 bit flat code descriptor */ 55 .value 0xFFFF /* segment limit 0..15 */ 56 .value 0x0000 /* segment base 0..15 */ 57 .byte 0x0 /* segment base 16..23 */ 58 .byte 0x9A /* P=1, code, exec, readable */ 59 .byte 0xCF /* G=1, D=1, Limit (16..19)=1111 */ 60 .byte 0x0 /* segment base 24..32 */ 61 62 /* 63 * GDT_B16CODE 16 bit code descriptor for doing BIOS calls 64 */ 65 .value 0xFFFF /* segment limit 0..15 */ 66 .value 0x0000 /* segment base 0..15 */ 67 .byte 0x0 /* segment base 16..23 */ 68 .byte 0x9A /* P=1, code, exec, readable */ 69 .byte 0x0F /* G=0, D=0, Limit (16..19)=1111 */ 70 .byte 0x0 /* segment base 24..32 */ 71 72 /* 73 * GDT_B16DATA 16 bit data descriptor for doing BIOS calls 74 * XXX: Note that this sets the B flag, which is not supposed to be 75 * set for a 16-bit data segment that is not expand-down (Intel SDM 76 * vol 3A sec 3.4.5). AMD does not seem to care (AMD APM vol 2 sec 77 * 2.7.4). It is likely this is here for use with stack segments, 78 * where it effects 32-bit operations. Conceivably, we could be more 79 * conservative and specify a 16-bit stack segment, but leave it for 80 * now. 81 */ 82 .value 0xFFFF /* segment limit 0..15 */ 83 .value 0x0000 /* segment base 0..15 */ 84 .byte 0x0 /* segment base 16..23 */ 85 .byte 0x92 /* P = 1, read/write data */ 86 .byte 0x4F /* G=0, B=1, Limit (16..19)=1111 */ 87 .byte 0x0 /* segment base 24..32 */ 88 89 /* GDT_B64CODE: 64 bit flat code descriptor - only L bit has meaning */ 90 .value 0xFFFF /* segment limit 0..15 */ 91 .value 0x0000 /* segment base 0..15 */ 92 .byte 0x0 /* segment base 16..23 */ 93 .byte 0x9A /* P=1, code, exec, readable */ 94 .byte 0xAF /* G=1, D=0, L=1, Limit (16..19)=1111 */ 95 .byte 0x0 /* segment base 24..32 */ 96 97 /* 98 * unused 99 */ 100 .long 0 101 .long 0 102 103 /* 104 * GDT_BGSTMP -- an entry for kmdb to use during boot 105 * the fast reboot code uses this entry for memory copies, too. 106 */ 107 .value 0x0001 /* segment limit 0..15 */ 108 109 .globl fake_cpu_gdt_base_0_15 110fake_cpu_gdt_base_0_15: 111 112 .value 0x0000 /* segment base 0..15 */ 113 114 .globl fake_cpu_gdt_base_16_23 115fake_cpu_gdt_base_16_23: 116 .byte 0x0 /* segment base 16..23 */ 117 .byte 0x9A /* P=1, code, exec, readable */ 118 .byte 0xC0 /* G=1, D=1, Limit (16..19)=0000 */ 119 120 .globl fake_cpu_gdt_base_24_31 121fake_cpu_gdt_base_24_31: 122 .byte 0x0 /* segment base 24..32 */ 123 124/ .long 0 125/ .long 0 126 127 128/* 129 * This is a desctbr_t. 130 */ 131gdt_info: 132 .value gdt_info - global_descriptor_table - 1 133 .long global_descriptor_table 134 .long 0 /* needed for 64 bit */ 135 136fake_cpu: 137 .4byte 0 138 .4byte 0 139 .4byte 0 140 .globl fake_cpu_ptr 141fake_cpu_ptr: 142 .4byte 0 143 .skip 0x6c0, 0 144 145