mpboot.S revision 38888 
1193323Sed/*
2193323Sed * Copyright (c) 1995, Jack F. Vogel
3193323Sed * All rights reserved.
4193323Sed *
5193323Sed * Redistribution and use in source and binary forms, with or without
6193323Sed * modification, are permitted provided that the following conditions
7193323Sed * are met:
8193323Sed * 1. Redistributions of source code must retain the above copyright
9193323Sed *    notice, this list of conditions and the following disclaimer.
10193323Sed * 2. Redistributions in binary form must reproduce the above copyright
11193323Sed *    notice, this list of conditions and the following disclaimer in the
12251662Sdim *    documentation and/or other materials provided with the distribution.
13198090Srdivacky * 3. All advertising materials mentioning features or use of this software
14193323Sed *    must display the following acknowledgement:
15193323Sed *	This product includes software developed by Jack F. Vogel
16193323Sed * 4. The name of the developer may be used to endorse or promote products
17193323Sed *    derived from this software without specific prior written permission.
18193323Sed *
19193323Sed * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20198090Srdivacky * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21263508Sdim * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22249423Sdim * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23198090Srdivacky * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24193323Sed * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25249423Sdim * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26198090Srdivacky * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27193323Sed * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28193323Sed * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29193323Sed * SUCH DAMAGE.
30204792Srdivacky *
31204792Srdivacky * mpboot.s:	FreeBSD machine support for the Intel MP Spec
32204792Srdivacky *		multiprocessor systems.
33249423Sdim *
34198090Srdivacky *	$Id: mpboot.s,v 1.6 1997/10/10 09:44:05 peter Exp $
35193323Sed */
36193323Sed
37193323Sed#include "opt_vm86.h"
38193323Sed
39204792Srdivacky#include <machine/asmacros.h>		/* miscellaneous asm macros */
40193323Sed#include <machine/apic.h>
41#include <machine/specialreg.h>
42
43#include "assym.s"
44
45/*
46 * this code MUST be enabled here and in mp_machdep.c
47 * it follows the very early stages of AP boot by placing values in CMOS ram.
48 * it NORMALLY will never be needed and thus the primitive method for enabling.
49 *
50#define CHECK_POINTS
51 */
52
53#if defined(CHECK_POINTS)
54
55#define CMOS_REG	(0x70)
56#define CMOS_DATA	(0x71)
57
58#define CHECKPOINT(A,D)		\
59	movb	$(A),%al ;	\
60	outb	%al,$CMOS_REG ;	\
61	movb	$(D),%al ;	\
62	outb	%al,$CMOS_DATA
63
64#else
65
66#define CHECKPOINT(A,D)
67
68#endif /* CHECK_POINTS */
69
70
71/*
72 * the APs enter here from their trampoline code (bootMP, below)
73 */
74	.p2align 4
75
76NON_GPROF_ENTRY(MPentry)
77	CHECKPOINT(0x36, 3)
78	/* Now enable paging mode */
79	movl	_bootPTD-KERNBASE, %eax
80	movl	%eax,%cr3
81	movl	%cr0,%eax
82	orl	$CR0_PE|CR0_PG,%eax		/* enable paging */
83	movl	%eax,%cr0			/* let the games begin! */
84	movl	$_idlestack_top,%esp		/* boot stack end loc. */
85
86	pushl	$mp_begin			/* jump to high mem */
87	ret
88
89	/*
90	 * Wait for the booting CPU to signal startup
91	 */
92mp_begin:	/* now running relocated at KERNBASE */
93	CHECKPOINT(0x37, 4)
94	call	_init_secondary			/* load i386 tables */
95	CHECKPOINT(0x38, 5)
96
97#ifdef VM86
98	/*
99	 * If the [BSP] CPU has support for VME, turn it on.
100	 */
101	testl	$CPUID_VME, _cpu_feature	/* XXX WRONG! BSP! */
102	jz	1f
103	movl	%cr4, %eax
104	orl	$CR4_VME, %eax
105	movl	%eax, %cr4
1061:
107#endif
108
109	/* disable the APIC, just to be SURE */
110	movl	lapic_svr, %eax			/* get spurious vector reg. */
111	andl	$~APIC_SVR_SWEN, %eax		/* clear software enable bit */
112	movl	%eax, lapic_svr
113
114	/* signal our startup to the BSP */
115	movl	lapic_ver, %eax			/* our version reg contents */
116	movl	%eax, _cpu_apic_versions	/* into [ 0 ] */
117	incl	_mp_ncpus			/* signal BSP */
118
119	CHECKPOINT(0x39, 6)
120
121	/* wait till we can get into the kernel */
122	call	_boot_get_mplock
123
124	/* Now, let's prepare for some REAL WORK :-) */
125	call	_ap_init
126
127	call	_rel_mplock
1282:
129	cmpl	$0, CNAME(smp_started)	/* Wait for last AP to be ready */
130	jz	2b
131	call _get_mplock
132
133	/* let her rip! (loads new stack) */
134	jmp 	_cpu_switch
135
136/*
137 * This is the embedded trampoline or bootstrap that is
138 * copied into 'real-mode' low memory, it is where the
139 * secondary processor "wakes up". When it is executed
140 * the processor will eventually jump into the routine
141 * MPentry, which resides in normal kernel text above
142 * 1Meg.		-jackv
143 */
144
145#define data32	.byte 0x66
146#define addr32	.byte 0x67
147
148	.data
149	ALIGN_DATA				/* just to be sure */
150
151BOOTMP1:
152
153NON_GPROF_ENTRY(bootMP)
154	cli
155	CHECKPOINT(0x34, 1)
156	/* First guarantee a 'clean slate' */
157	data32
158	xorl	%eax, %eax
159	data32
160	movl	%eax, %ebx
161	data32
162	movl	%eax, %ecx
163	data32
164 	movl	%eax, %edx
165	data32
166	movl	%eax, %esi
167	data32
168	movl	%eax, %edi
169
170	/* set up data segments */
171	mov	%cs, %ax
172	mov	%ax, %ds
173	mov	%ax, %es
174	mov	%ax, %fs
175	mov	%ax, %gs
176	mov	%ax, %ss
177	mov	$(boot_stk-_bootMP), %sp
178
179	/* Now load the global descriptor table */
180	addr32
181	data32
182	/* XXX: sigh: lgdt	MP_GDTptr-_bootMP GAS BUG! */
183	.byte	0x0f, 0x01, 0x15		/* XXX hand assemble! */
184	.long	MP_GDTptr-_bootMP		/* XXX hand assemble! */
185
186	/* Enable protected mode */
187	data32
188	movl	%cr0, %eax
189	data32
190	orl	$CR0_PE, %eax
191	data32
192	movl	%eax, %cr0
193
194	/*
195	 * make intrasegment jump to flush the processor pipeline and
196	 * reload CS register
197	 */
198	data32
199	pushl	$0x18
200	data32
201	pushl	$(protmode-_bootMP)
202	data32
203	lret
204
205protmode:
206	CHECKPOINT(0x35, 2)
207
208	/*
209	 * we are NOW running for the first time with %eip
210	 * having the full physical address, BUT we still
211	 * are using a segment descriptor with the origin
212	 * not matching the booting kernel.
213	 *
214 	 * SO NOW... for the BIG Jump into kernel's segment
215	 * and physical text above 1 Meg.
216	 */
217	mov	$0x10, %ebx
218	movw	%bx, %ds
219	movw	%bx, %es
220	movw	%bx, %fs
221	movw	%bx, %gs
222	movw	%bx, %ss
223
224	.globl	_bigJump
225_bigJump:
226	/* this will be modified by mpInstallTramp() */
227	ljmp	$0x08, $0			/* far jmp to MPentry() */
228
229dead:	hlt /* We should never get here */
230	jmp	dead
231
232/*
233 * MP boot strap Global Descriptor Table
234 */
235	.p2align 4
236	.globl	_MP_GDT
237	.globl	_bootCodeSeg
238	.globl	_bootDataSeg
239_MP_GDT:
240
241nulldesc:		/* offset = 0x0 */
242
243	.word	0x0
244	.word	0x0
245	.byte	0x0
246	.byte	0x0
247	.byte	0x0
248	.byte	0x0
249
250kernelcode:		/* offset = 0x08 */
251
252	.word	0xffff	/* segment limit 0..15 */
253	.word	0x0000	/* segment base 0..15 */
254	.byte	0x0	/* segment base 16..23; set for 0K */
255	.byte	0x9f	/* flags; Type	*/
256	.byte	0xcf	/* flags; Limit	*/
257	.byte	0x0	/* segment base 24..32 */
258
259kerneldata:		/* offset = 0x10 */
260
261	.word	0xffff	/* segment limit 0..15 */
262	.word	0x0000	/* segment base 0..15 */
263	.byte	0x0	/* segment base 16..23; set for 0k */
264	.byte	0x93	/* flags; Type  */
265	.byte	0xcf	/* flags; Limit */
266	.byte	0x0	/* segment base 24..32 */
267
268bootcode:		/* offset = 0x18 */
269
270	.word	0xffff	/* segment limit 0..15 */
271_bootCodeSeg:		/* this will be modified by mpInstallTramp() */
272	.word	0x0000	/* segment base 0..15 */
273	.byte	0x00	/* segment base 16...23; set for 0x000xx000 */
274	.byte	0x9e	/* flags; Type  */
275	.byte	0xcf	/* flags; Limit */
276	.byte	0x0	/*segment base 24..32 */
277
278bootdata:		/* offset = 0x20 */
279
280	.word	0xffff
281_bootDataSeg:		/* this will be modified by mpInstallTramp() */
282	.word	0x0000	/* segment base 0..15 */
283	.byte	0x00	/* segment base 16...23; set for 0x000xx000 */
284	.byte	0x92
285	.byte	0xcf
286	.byte	0x0
287
288/*
289 * GDT pointer for the lgdt call
290 */
291	.globl	_mp_gdtbase
292
293MP_GDTptr:
294_mp_gdtlimit:
295	.word	0x0028
296_mp_gdtbase:		/* this will be modified by mpInstallTramp() */
297	.long	0
298
299	.space	0x100	/* space for boot_stk - 1st temporary stack */
300boot_stk:
301
302BOOTMP2:
303	.globl	_bootMP_size
304_bootMP_size:
305	.long	BOOTMP2 - BOOTMP1
306