sys/platform/pc32/i386/mpboot.s

   1 /*
   2  * Copyright (c) 1995, Jack F. Vogel
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   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.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by Jack F. Vogel
  16  * 4. The name of the developer may be used to endorse or promote products
  17  *    derived from this software without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  * mpboot.s:    FreeBSD machine support for the Intel MP Spec
  32  *              multiprocessor systems.
  33  *
  34  * $FreeBSD: src/sys/i386/i386/mpboot.s,v 1.13.2.3 2000/09/07 01:18:26 tegge Exp $
  35  * $DragonFly: src/sys/platform/pc32/i386/mpboot.s,v 1.11 2006/11/07 06:43:24 dillon Exp $
  36  */
  37
  38 #include <machine/asmacros.h>           /* miscellaneous asm macros */
  39 #include <machine_base/apic/apicreg.h>
  40 #include <machine/specialreg.h>
  41
  42 #include "assym.s"
  43
  44 /*
  45  * this code MUST be enabled here and in mp_machdep.c for debugging.
  46  * it follows the very early stages of AP boot by placing values in CMOS ram.
  47  * it NORMALLY will never be needed and thus the primitive method for enabling.
  48  *
  49  * WARNING!  DEFINING THIS OPTION MAY CAUSE THE CMOS CHECKSUM TO FAIL AND THE
  50  * BIOS MIGHT COMPLAIN.  ENABLE THIS OPTION FOR DEBUGGING THE BOOT PATH ONLY.
  51  *
  52 #define CHECK_POINTS
  53  */
  54
  55 #if defined(CHECK_POINTS)
  56
  57 #define CMOS_REG        (0x70)
  58 #define CMOS_DATA       (0x71)
  59
  60 #define CHECKPOINT(A,D)         \
  61         movb    $A,%al ;        \
  62         outb    %al,$CMOS_REG ; \
  63         movb    D,%al ;         \
  64         outb    %al,$CMOS_DATA
  65
  66 #else
  67
  68 #define CHECKPOINT(A,D)
  69
  70 #endif /* CHECK_POINTS */
  71
  72
  73 /*
  74  * The APs enter here from their trampoline code (bootMP, below)
  75  * NOTE: %fs is not setup until the call to init_secondary()!
  76  */
  77         .p2align 4
  78
  79 NON_GPROF_ENTRY(MPentry)
  80         CHECKPOINT(0x36, $3)
  81         /* Now enable paging mode */
  82         movl    IdlePTD-KERNBASE, %eax
  83         movl    %eax,%cr3
  84         movl    %cr0,%eax
  85         orl     $CR0_PE|CR0_PG,%eax             /* enable paging */
  86         movl    %eax,%cr0                       /* let the games begin! */
  87
  88         movl    bootSTK,%esp                    /* boot stack end loc. */
  89         pushl   $mp_begin                       /* jump to high mem */
  90         NON_GPROF_RET
  91
  92         /*
  93          * Wait for the booting CPU to signal startup
  94          */
  95 mp_begin:       /* now running relocated at KERNBASE */
  96         CHECKPOINT(0x37, $4)
  97         call    init_secondary                  /* load i386 tables */
  98         CHECKPOINT(0x38, $5)
  99
 100         /*
 101          * If the [BSP] CPU has support for VME, turn it on.
 102          */
 103         testl   $CPUID_VME, cpu_feature         /* XXX WRONG! BSP! */
 104         jz      1f
 105         movl    %cr4, %eax
 106         orl     $CR4_VME, %eax
 107         movl    %eax, %cr4
 108 1:
 109
 110         CHECKPOINT(0x39, $6)
 111
 112         /*
 113          * Execute the context restore function for the idlethread which
 114          * has conveniently been set as curthread.  Remember, %eax must
 115          * contain the target thread and %ebx must contain the originating
 116          * thread (which we just set the same since we have no originating
 117          * thread).  BSP/AP synchronization occurs in ap_init().  We do
 118          * not need to mess with the BGL for this because LWKT threads are
 119          * self-contained on each cpu (or, at least, the idlethread is!).
 120          */
 121         movl    PCPU(curthread),%eax
 122         movl    %eax,%ebx
 123         movl    TD_SP(%eax),%esp
 124         ret
 125
 126 /*
 127  * This is the embedded trampoline or bootstrap that is
 128  * copied into 'real-mode' low memory, it is where the
 129  * secondary processor "wakes up". When it is executed
 130  * the processor will eventually jump into the routine
 131  * MPentry, which resides in normal kernel text above
 132  * 1Meg.                -jackv
 133  */
 134
 135         .data
 136         ALIGN_DATA                              /* just to be sure */
 137
 138 BOOTMP1:
 139
 140 NON_GPROF_ENTRY(bootMP)
 141         .code16
 142         cli
 143         CHECKPOINT(0x34, $1)
 144         /* First guarantee a 'clean slate' */
 145         xorl    %eax, %eax
 146         movl    %eax, %ebx
 147         movl    %eax, %ecx
 148         movl    %eax, %edx
 149         movl    %eax, %esi
 150         movl    %eax, %edi
 151
 152         /* set up data segments */
 153         mov     %cs, %ax
 154         mov     %ax, %ds
 155         mov     %ax, %es
 156         mov     %ax, %fs
 157         mov     %ax, %gs
 158         mov     %ax, %ss
 159         mov     $(boot_stk - bootMP), %esp
 160
 161         /* Now load the global descriptor table */
 162         lgdt    MP_GDTptr - bootMP
 163
 164         /* Enable protected mode */
 165         movl    %cr0, %eax
 166         orl     $CR0_PE, %eax
 167         movl    %eax, %cr0
 168
 169         /*
 170          * make intrasegment jump to flush the processor pipeline and
 171          * reload CS register
 172          */
 173         pushl   $0x18
 174         pushl   $(protmode - bootMP)
 175         lretl
 176
 177        .code32
 178 protmode:
 179         CHECKPOINT(0x35, $2)
 180
 181         /*
 182          * we are NOW running for the first time with %eip
 183          * having the full physical address, BUT we still
 184          * are using a segment descriptor with the origin
 185          * not matching the booting kernel.
 186          *
 187          * SO NOW... for the BIG Jump into kernel's segment
 188          * and physical text above 1 Meg.
 189          */
 190         mov     $0x10, %ebx
 191         movw    %bx, %ds
 192         movw    %bx, %es
 193         movw    %bx, %fs
 194         movw    %bx, %gs
 195         movw    %bx, %ss
 196
 197         .globl  bigJump
 198 bigJump:
 199         /* this will be modified by mpInstallTramp() */
 200         ljmp    $0x08, $0                       /* far jmp to MPentry() */
 201
 202 dead:   hlt /* We should never get here */
 203         jmp     dead
 204
 205 /*
 206  * MP boot strap Global Descriptor Table
 207  */
 208         .p2align 4
 209         .globl  MP_GDT
 210         .globl  bootCodeSeg
 211         .globl  bootDataSeg
 212 MP_GDT:
 213
 214 nulldesc:               /* offset = 0x0 */
 215
 216         .word   0x0
 217         .word   0x0
 218         .byte   0x0
 219         .byte   0x0
 220         .byte   0x0
 221         .byte   0x0
 222
 223 kernelcode:             /* offset = 0x08 */
 224
 225         .word   0xffff  /* segment limit 0..15 */
 226         .word   0x0000  /* segment base 0..15 */
 227         .byte   0x0     /* segment base 16..23; set for 0K */
 228         .byte   0x9f    /* flags; Type  */
 229         .byte   0xcf    /* flags; Limit */
 230         .byte   0x0     /* segment base 24..32 */
 231
 232 kerneldata:             /* offset = 0x10 */
 233
 234         .word   0xffff  /* segment limit 0..15 */
 235         .word   0x0000  /* segment base 0..15 */
 236         .byte   0x0     /* segment base 16..23; set for 0k */
 237         .byte   0x93    /* flags; Type  */
 238         .byte   0xcf    /* flags; Limit */
 239         .byte   0x0     /* segment base 24..32 */
 240
 241 bootcode:               /* offset = 0x18 */
 242
 243         .word   0xffff  /* segment limit 0..15 */
 244 bootCodeSeg:            /* this will be modified by mpInstallTramp() */
 245         .word   0x0000  /* segment base 0..15 */
 246         .byte   0x00    /* segment base 16...23; set for 0x000xx000 */
 247         .byte   0x9e    /* flags; Type  */
 248         .byte   0xcf    /* flags; Limit */
 249         .byte   0x0     /*segment base 24..32 */
 250
 251 bootdata:               /* offset = 0x20 */
 252
 253         .word   0xffff
 254 bootDataSeg:            /* this will be modified by mpInstallTramp() */
 255         .word   0x0000  /* segment base 0..15 */
 256         .byte   0x00    /* segment base 16...23; set for 0x000xx000 */
 257         .byte   0x92
 258         .byte   0xcf
 259         .byte   0x0
 260
 261 /*
 262  * GDT pointer for the lgdt call
 263  */
 264         .globl  mp_gdtbase
 265
 266 MP_GDTptr:
 267 mp_gdtlimit:
 268         .word   0x0028
 269 mp_gdtbase:             /* this will be modified by mpInstallTramp() */
 270         .long   0
 271
 272         .space  0x100   /* space for boot_stk - 1st temporary stack */
 273 boot_stk:
 274
 275 BOOTMP2:
 276         .globl  bootMP_size
 277 bootMP_size:
 278         .long   BOOTMP2 - BOOTMP1
 279