2 * Copyright (c) 1995 Jack F. Vogel
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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17 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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26 * mpboot.s: FreeBSD machine support for the Intel MP Spec
27 * multiprocessor systems.
34 #include <machine/asmacros.h> /* miscellaneous asm macros */
35 #include <x86/apicreg.h>
36 #include <machine/specialreg.h>
41 * this code MUST be enabled here and in mp_machdep.c
42 * it follows the very early stages of AP boot by placing values in CMOS ram.
43 * it NORMALLY will never be needed and thus the primitive method for enabling.
48 #if defined(CHECK_POINTS)
50 #define CMOS_REG (0x70)
51 #define CMOS_DATA (0x71)
53 #define CHECKPOINT(A,D) \
55 outb %al,$CMOS_REG ; \
61 #define CHECKPOINT(A,D)
63 #endif /* CHECK_POINTS */
67 * the APs enter here from their trampoline code (bootMP, below)
71 NON_GPROF_ENTRY(MPentry)
74 * Enable features on this processor. We don't support SMP on
75 * CPUs older than a Pentium, so we know that we can use the cpuid
79 cpuid /* Retrieve features */
83 orl $CR4_PSE,%eax /* Enable PSE */
87 orl $CR4_PGE,%eax /* Enable PGE */
91 orl $CR4_VME,%eax /* Enable VME */
95 /* Now enable paging mode */
96 #if defined(PAE) || defined(PAE_TABLES)
107 orl $CR0_PE|CR0_PG,%eax /* enable paging */
108 movl %eax,%cr0 /* let the games begin! */
109 movl bootSTK,%esp /* boot stack end loc. */
111 pushl $mp_begin /* jump to high mem */
115 * Wait for the booting CPU to signal startup
117 mp_begin: /* now running relocated at KERNBASE */
119 call init_secondary /* load i386 tables */
122 * This is the embedded trampoline or bootstrap that is
123 * copied into 'real-mode' low memory, it is where the
124 * secondary processor "wakes up". When it is executed
125 * the processor will eventually jump into the routine
126 * MPentry, which resides in normal kernel text above
131 ALIGN_DATA /* just to be sure */
135 NON_GPROF_ENTRY(bootMP)
139 /* First guarantee a 'clean slate' */
147 /* set up data segments */
154 mov $(boot_stk-bootMP), %esp
156 /* Now load the global descriptor table */
157 lgdt MP_GDTptr-bootMP
159 /* Enable protected mode */
165 * make intrasegment jump to flush the processor pipeline and
169 pushl $(protmode-bootMP)
177 * we are NOW running for the first time with %eip
178 * having the full physical address, BUT we still
179 * are using a segment descriptor with the origin
180 * not matching the booting kernel.
182 * SO NOW... for the BIG Jump into kernel's segment
183 * and physical text above 1 Meg.
194 /* this will be modified by mpInstallTramp() */
195 ljmp $0x08, $0 /* far jmp to MPentry() */
197 dead: hlt /* We should never get here */
201 * MP boot strap Global Descriptor Table
209 nulldesc: /* offset = 0x0 */
218 kernelcode: /* offset = 0x08 */
220 .word 0xffff /* segment limit 0..15 */
221 .word 0x0000 /* segment base 0..15 */
222 .byte 0x0 /* segment base 16..23; set for 0K */
223 .byte 0x9f /* flags; Type */
224 .byte 0xcf /* flags; Limit */
225 .byte 0x0 /* segment base 24..32 */
227 kerneldata: /* offset = 0x10 */
229 .word 0xffff /* segment limit 0..15 */
230 .word 0x0000 /* segment base 0..15 */
231 .byte 0x0 /* segment base 16..23; set for 0k */
232 .byte 0x93 /* flags; Type */
233 .byte 0xcf /* flags; Limit */
234 .byte 0x0 /* segment base 24..32 */
236 bootcode: /* offset = 0x18 */
238 .word 0xffff /* segment limit 0..15 */
239 bootCodeSeg: /* this will be modified by mpInstallTramp() */
240 .word 0x0000 /* segment base 0..15 */
241 .byte 0x00 /* segment base 16...23; set for 0x000xx000 */
242 .byte 0x9e /* flags; Type */
243 .byte 0xcf /* flags; Limit */
244 .byte 0x0 /*segment base 24..32 */
246 bootdata: /* offset = 0x20 */
249 bootDataSeg: /* this will be modified by mpInstallTramp() */
250 .word 0x0000 /* segment base 0..15 */
251 .byte 0x00 /* segment base 16...23; set for 0x000xx000 */
257 * GDT pointer for the lgdt call
264 mp_gdtbase: /* this will be modified by mpInstallTramp() */
267 .space 0x100 /* space for boot_stk - 1st temporary stack */
273 .long BOOTMP2 - BOOTMP1