arch/arm-efika/kernel/kernel_startup.c

   1 /*
   2     Copyright © 1995-2010, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc:
   6     Lang: english
   7 */
   8
   9 #include <utility/tagitem.h>
  10 #include <proto/arossupport.h>
  11 #include <strings.h>
  12 #include <inttypes.h>
  13
  14 #include <aros/arm/cpucontext.h>
  15
  16 #include <kernel_base.h>
  17 #include <kernel_debug.h>
  18
  19 #define _STR(x) #x
  20 #define STR(x) _STR(x)
  21
  22 #define SYS_STACK_SIZE  (16384)
  23
  24 asm(".section .aros.init,\"ax\"\n\t"
  25     ".globl start\n\t"
  26     ".type start,%function\n"
  27     "start: ldr sp, tmp_stack_end   \n"     // Load address of top of stack pointer
  28     "       mov r4, r0              \n"
  29     "       bl  clear_bss           \n"     // clear bss regions
  30     "       mov r0, r4              \n"     // restore boot msg parameter
  31     "       cps #" STR(CPUMODE_SYSTEM) "\n"     // Enter System mode
  32     "       ldr sp, sys_stack_end   \n"     // Load system mode stack
  33     "       cps #" STR(CPUMODE_IRQ) "\n"
  34     "       ldr sp, irq_stack_end   \n"
  35     "       cps #" STR(CPUMODE_ABORT) "\n"
  36     "       ldr sp, abt_stack_end   \n"
  37     "       cps #" STR(CPUMODE_SUPERVISOR) "\n"
  38     "       ldr sp, svc_stack_end   \n"
  39     "       ldr pc, 2f              \n"     // jump to the kernel
  40     "1:     b   1b                  \n"     // we never return from here
  41     "2:     .word startup           \n"
  42     "tmp_stack_end: .word temporary + " STR(127*4) "\n"
  43     "sys_stack_end: .word sys_stack + " STR((SYS_STACK_SIZE - 4)) "\n"
  44     "svc_stack_end: .word svc_stack + " STR((SYS_STACK_SIZE - 4)) "\n"
  45     "irq_stack_end: .word irq_stack + " STR((SYS_STACK_SIZE - 4)) "\n"
  46     "abt_stack_end: .word abt_stack + " STR((SYS_STACK_SIZE - 4)) "\n"
  47 );
  48
  49 /*
  50  * Temporary stack for very early init. It's used only during clearing of
  51  * .bss sections in all modules. Rest of this space is occupied by TagItem
  52  * boot message. prepared by the bootstrap.
  53  */
  54 static union {
  55         uint32_t                stack[128];
  56         struct TagItem  tags[64];
  57 } temporary __attribute__((aligned(32),used,section(".data")));
  58
  59 static uint8_t sys_stack[SYS_STACK_SIZE] __attribute__((used,aligned(16)));
  60 static uint8_t svc_stack[SYS_STACK_SIZE] __attribute__((used,aligned(16)));
  61 static uint8_t abt_stack[SYS_STACK_SIZE] __attribute__((used,aligned(16)));
  62 static uint8_t irq_stack[SYS_STACK_SIZE] __attribute__((used,aligned(16)));
  63
  64 //static uint32_t * const sys_stack_end __attribute__((used,section(".aros.init"))) = &sys_stack[SYS_STACK_SIZE-1];
  65 //static uint32_t * const svc_stack_end __attribute__((used,section(".aros.init"))) = &svc_stack[SYS_STACK_SIZE-1];
  66 //static uint32_t * const abt_stack_end __attribute__((used,section(".aros.init"))) = &abt_stack[SYS_STACK_SIZE-1];
  67 //static uint32_t * const irq_stack_end __attribute__((used,section(".aros.init"))) = &irq_stack[SYS_STACK_SIZE-1];
  68
  69 //static uint32_t * const tmp_stack_end __attribute__((used,section(".aros.init"))) = &temporary.stack[128 - 1];
  70
  71 struct TagItem *BootMsg;
  72
  73 static void __used __attribute__((section(".aros.init"))) clear_bss(struct TagItem *msg)
  74 {
  75         struct TagItem *tag = LibFindTagItem(KRN_KernelBss, msg);
  76
  77         if (tag)
  78         {
  79                 struct KernelBSS *bss = (struct KernelBSS *)tag->ti_Data;
  80
  81                 if (bss)
  82                 {
  83                         __clear_bss(bss);
  84                 }
  85         }
  86 }
  87
  88 void startup(struct TagItem *tags)
  89 {
  90         bug("\n[KRN] AROS for EfikaMX built on %s starting...\n", __DATE__);
  91         bug("[KRN] BootMsg @ %08x\n", tags);
  92
  93         while(1);
  94 }