apbootstrap.s

Version: - FREEBSD - FREEBSD-13-STABLE - FREEBSD-13-0 - FREEBSD-12-STABLE - FREEBSD-12-0 - FREEBSD-11-STABLE - FREEBSD-11-0 - FREEBSD-10-STABLE - FREEBSD-10-0 - FREEBSD-9-STABLE - FREEBSD-9-0 - FREEBSD-8-STABLE - FREEBSD-8-0 - FREEBSD-7-STABLE - FREEBSD-7-0 - FREEBSD-6-STABLE - FREEBSD-6-0 - FREEBSD-5-STABLE - FREEBSD-5-0 - FREEBSD-4-STABLE - FREEBSD-3-STABLE - FREEBSD22 - l41 - OPENBSD - linux-2.6 - MK84 - PLAN9 - xnu-8792
SearchContext: - none - 3 - 10

    1 /*
    2  * Start an Application Processor. This must be placed on a 4KB boundary
    3  * somewhere in the 1st MB of conventional memory (APBOOTSTRAP). However,
    4  * due to some shortcuts below it's restricted further to within the 1st
    5  * 64KB. The AP starts in real-mode, with
    6  *   CS selector set to the startup memory address/16;
    7  *   CS base set to startup memory address;
    8  *   CS limit set to 64KB;
    9  *   CPL and IP set to 0.
   10  */
   11 #include "mem.h"
   12 
   13 #define NOP             BYTE $0x90              /* NOP */
   14 #define LGDT(gdtptr)    BYTE $0x0F;             /* LGDT */                      \
   15                         BYTE $0x01; BYTE $0x16;                                 \
   16                         WORD $gdtptr
   17 #define FARJUMP16(s, o) BYTE $0xEA;             /* far jump to ptr16:16 */      \
   18                         WORD $o; WORD $s;                                       \
   19                         NOP; NOP; NOP
   20 #define FARJUMP32(s, o) BYTE $0x66;             /* far jump to ptr32:16 */      \
   21                         BYTE $0xEA; LONG $o; WORD $s
   22 
   23 #define DELAY           BYTE $0xEB;             /* JMP .+2 */                   \
   24                         BYTE $0x00
   25 #define INVD            BYTE $0x0F; BYTE $0x08
   26 #define WBINVD          BYTE $0x0F; BYTE $0x09
   27 
   28 /*
   29  * Macros for calculating offsets within the page directory base
   30  * and page tables. Note that these are assembler-specific hence
   31  * the '<<2'.
   32  */
   33 #define PDO(a)          (((((a))>>22) & 0x03FF)<<2)
   34 #define PTO(a)          (((((a))>>12) & 0x03FF)<<2)
   35 
   36 TEXT apbootstrap(SB), $0
   37         FARJUMP16(0, _apbootstrap(SB))
   38 TEXT _apvector(SB), $0                          /* address APBOOTSTRAP+0x08 */
   39         LONG $0
   40 TEXT _appdb(SB), $0                             /* address APBOOTSTRAP+0x0C */
   41         LONG $0
   42 TEXT _apapic(SB), $0                            /* address APBOOTSTRAP+0x10 */
   43         LONG $0
   44 TEXT _apbootstrap(SB), $0                       /* address APBOOTSTRAP+0x14 */
   45         MOVW    CS, AX
   46         MOVW    AX, DS                          /* initialise DS */
   47 
   48         LGDT(gdtptr(SB))                        /* load a basic gdt */
   49 
   50         MOVL    CR0, AX
   51         ORL     $1, AX
   52         MOVL    AX, CR0                         /* turn on protected mode */
   53         DELAY                                   /* JMP .+2 */
   54 
   55         BYTE $0xB8; WORD $SELECTOR(1, SELGDT, 0)/* MOVW $SELECTOR(1, SELGDT, 0), AX */
   56         MOVW    AX, DS
   57         MOVW    AX, ES
   58         MOVW    AX, FS
   59         MOVW    AX, GS
   60         MOVW    AX, SS
   61 
   62         FARJUMP32(SELECTOR(2, SELGDT, 0), _ap32-KZERO(SB))
   63 
   64 /*
   65  * For Pentiums and higher, the code that enables paging must come from
   66  * pages that are identity mapped. 
   67  * To this end double map KZERO at virtual 0 and undo the mapping once virtual
   68  * nirvana has been obtained.
   69  */
   70 TEXT _ap32(SB), $0
   71         MOVL    _appdb-KZERO(SB), CX            /* physical address of PDB */
   72         MOVL    (PDO(KZERO))(CX), DX            /* double-map KZERO at 0 */
   73         MOVL    DX, (PDO(0))(CX)
   74         MOVL    CX, CR3                         /* load and flush the mmu */
   75 
   76         MOVL    CR0, DX
   77         ORL     $0x80010000, DX                 /* PG|WP */
   78         ANDL    $~0x6000000A, DX                /* ~(CD|NW|TS|MP) */
   79 
   80         MOVL    $_appg(SB), AX
   81         MOVL    DX, CR0                         /* turn on paging */
   82         JMP*    AX
   83 
   84 TEXT _appg(SB), $0
   85         MOVL    CX, AX                          /* physical address of PDB */
   86         ORL     $KZERO, AX
   87         MOVL    $0, (PDO(0))(AX)                /* undo double-map of KZERO at 0 */
   88         MOVL    CX, CR3                         /* load and flush the mmu */
   89 
   90         MOVL    $(MACHADDR+MACHSIZE-4), SP
   91 
   92         MOVL    $0, AX
   93         PUSHL   AX
   94         POPFL
   95 
   96         MOVL    _apapic(SB), AX
   97         MOVL    AX, (SP)
   98         MOVL    _apvector(SB), AX
   99         CALL*   AX
  100 _aphalt:
  101         HLT
  102         JMP     _aphalt
  103 
  104 TEXT gdt(SB), $0
  105         LONG $0x0000; LONG $0
  106         LONG $0xFFFF; LONG $(SEGG|SEGB|(0xF<<16)|SEGP|SEGPL(0)|SEGDATA|SEGW)
  107         LONG $0xFFFF; LONG $(SEGG|SEGD|(0xF<<16)|SEGP|SEGPL(0)|SEGEXEC|SEGR)
  108 TEXT gdtptr(SB), $0
  109         WORD    $(3*8-1)
  110         LONG    $gdt-KZERO(SB)

Cache object: a73da83ef7133bfc573adfb313e784c1

[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.

FreeBSD/Linux Kernel Cross Reference sys/pc/apbootstrap.s

FreeBSD/Linux Kernel Cross Reference
sys/pc/apbootstrap.s