LXR linux/arch/m68k/kernel/sun3-head.S

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#include <linux/linkage.h>
   3#include <linux/init.h>
   4
   5#include <asm/entry.h>
   6#include <asm/page.h>
   7#include <asm/contregs.h>
   8#include <asm/sun3-head.h>
   9
  10PSL_HIGHIPL     = 0x2700
  11NBSG            = 0x20000
  12ICACHE_ONLY     = 0x00000009
  13CACHES_OFF      = 0x00000008    | actually a clear and disable --m
  14#define MAS_STACK INT_STACK
  15ROOT_TABLE_SIZE = 128
  16PAGESIZE        = 8192
  17SUN3_INVALID_PMEG = 255
  18.globl bootup_user_stack
  19.globl bootup_kernel_stack
  20.globl pg0
  21.globl swapper_pg_dir
  22.globl kernel_pmd_table
  23.globl availmem
  24.global m68k_pgtable_cachemode
  25.global kpt
  26| todo: all these should be in bss!
  27swapper_pg_dir:                .skip 0x2000
  28pg0:                           .skip 0x2000
  29kernel_pmd_table:              .skip 0x2000
  30
  31.globl kernel_pg_dir
  32.equ    kernel_pg_dir,kernel_pmd_table
  33
  34        __HEAD
  35ENTRY(_stext)
  36ENTRY(_start)
  37
  38/* Firstly, disable interrupts and set up function codes. */
  39        movew   #PSL_HIGHIPL, %sr
  40        moveq   #FC_CONTROL, %d0
  41        movec   %d0, %sfc
  42        movec   %d0, %dfc
  43
  44/* Make sure we're in context zero. */
  45        moveq   #0, %d0
  46        movsb   %d0, AC_CONTEXT
  47
  48/* map everything the bootloader left us into high memory, clean up the
  49   excess later */
  50        lea     (AC_SEGMAP+0),%a0
  51        lea     (AC_SEGMAP+KERNBASE),%a1
  521:
  53        movsb   %a0@, %d1
  54        movsb   %d1, %a1@
  55        cmpib   #SUN3_INVALID_PMEG, %d1
  56        beq     2f
  57        addl    #NBSG,%a0
  58        addl    #NBSG,%a1
  59        jmp     1b
  60
  612:
  62
  63/* Disable caches and jump to high code. */
  64        moveq   #ICACHE_ONLY,%d0        | Cache disabled until we're ready to enable it
  65        movc    %d0, %cacr      |   is this the right value? (yes --m)
  66        jmp     1f:l
  67
  68/* Following code executes at high addresses (0xE000xxx). */
  691:      lea     init_task,%curptr                       | get initial thread...
  70        lea     init_thread_union+THREAD_SIZE,%sp       | ...and its stack.
  71
  72/* Point MSP at an invalid page to trap if it's used. --m */
  73        movl    #(PAGESIZE),%d0
  74        movc    %d0,%msp
  75        moveq   #-1,%d0
  76        movsb   %d0,(AC_SEGMAP+0x0)
  77
  78        jbsr    sun3_init
  79
  80        jbsr    base_trap_init
  81
  82        jbsr    start_kernel
  83        trap    #15
  84
  85        .data
  86        .even
  87kpt:
  88        .long 0
  89availmem:
  90        .long 0
  91| todo: remove next two. --m
  92is_medusa:
  93        .long 0
  94m68k_pgtable_cachemode:
  95        .long 0
  96
  97