arch/m68knommu/platform/68328/head-ram.S

   1 #include <linux/config.h>
   2
   3         .global __main
   4         .global __ram_start
   5         .global __ram_end
   6         .global __rom_start
   7         .global __rom_end
   8
   9         .global _rambase
  10         .global _ramstart
  11
  12         .global splash_bits
  13         .global _start
  14         .global _stext
  15
  16 #define DEBUG
  17 #define ROM_OFFSET 0x10C00000
  18 #define STACK_GAURD 0x10
  19
  20         .text
  21
  22 _start:
  23 _stext:
  24         movew   #0x2700, %sr            /* Exceptions off! */
  25
  26 #if 0
  27         /* Init chip registers.  uCsimm specific */
  28         moveb   #0x00,   0xfffffb0b     /* Watchdog off */
  29         moveb   #0x10,   0xfffff000     /* SCR */
  30
  31         movew   #0x2400, 0xfffff200     /* PLLCR */
  32         movew   #0x0123, 0xfffff202     /* PLLFSR */
  33
  34         moveb   #0x00,   0xfffff40b     /* enable chip select */
  35         moveb   #0x00,   0xfffff423     /* enable /DWE */
  36         moveb   #0x08,   0xfffffd0d     /* disable hardmap */
  37         moveb   #0x07,   0xfffffd0e     /* level 7 interrupt clear */
  38
  39         movew   #0x8600, 0xfffff100     /* FLASH at 0x10c00000 */
  40         movew   #0x018b, 0xfffff110     /* 2Meg, enable, 0ws */
  41
  42         movew   #0x8f00, 0xfffffc00     /* DRAM configuration */
  43         movew   #0x9667, 0xfffffc02     /* DRAM control */
  44         movew   #0x0000, 0xfffff106     /* DRAM at 0x00000000 */
  45         movew   #0x068f, 0xfffff116     /* 8Meg, enable, 0ws */
  46
  47         moveb   #0x40,   0xfffff300     /* IVR */
  48         movel   #0x007FFFFF, %d0        /* IMR */
  49         movel   %d0,     0xfffff304
  50
  51         moveb   0xfffff42b, %d0
  52         andb    #0xe0,   %d0
  53         moveb   %d0,     0xfffff42b
  54
  55         moveb   #0x08,   0xfffff907     /* Ignore CTS */
  56         movew   #0x010b, 0xfffff902     /* BAUD to 9600 */
  57         movew   #0xe100, 0xfffff900     /* enable */
  58 #endif
  59
  60         movew   #16384, %d0  /* PLL settle wait loop */
  61 L0:
  62         subw    #1, %d0
  63         bne     L0
  64 #ifdef DEBUG
  65         moveq   #70, %d7                /* 'F' */
  66         moveb   %d7,0xfffff907          /* No absolute addresses */
  67 pclp1:
  68         movew   0xfffff906, %d7
  69         andw    #0x2000, %d7
  70         beq     pclp1
  71 #endif /* DEBUG */
  72
  73 #ifdef CONFIG_RELOCATE
  74         /* Copy me to RAM */
  75         moveal  #__rom_start, %a0
  76         moveal  #__ram_start, %a1
  77         moveal  #_edata, %a2
  78
  79         /* Copy %a0 to %a1 until %a1 == %a2 */
  80 LD1:
  81         movel   %a0@+, %d0
  82         movel   %d0, %a1@+
  83         cmpal   %a1, %a2
  84         bhi     LD1
  85
  86 #ifdef DEBUG
  87         moveq   #74, %d7                /* 'J' */
  88         moveb   %d7,0xfffff907          /* No absolute addresses */
  89 pclp2:
  90         movew   0xfffff906, %d7
  91         andw    #0x2000, %d7
  92         beq     pclp2
  93 #endif /* DEBUG */
  94         /* jump into the RAM copy */
  95         jmp     ram_jump
  96 ram_jump:
  97
  98 #endif /* CONFIG_RELOCATE */
  99
 100 #ifdef DEBUG
 101         moveq   #82, %d7                /* 'R' */
 102         moveb   %d7,0xfffff907          /* No absolute addresses */
 103 pclp3:
 104         movew   0xfffff906, %d7
 105         andw    #0x2000, %d7
 106         beq     pclp3
 107 #endif /* DEBUG */
 108         moveal  #0x007ffff0, %ssp
 109         moveal  #_sbss, %a0
 110         moveal  #_ebss, %a1
 111
 112         /* Copy 0 to %a0 until %a0 >= %a1 */
 113 L1:
 114         movel   #0, %a0@+
 115         cmpal   %a0, %a1
 116         bhi     L1
 117
 118 #ifdef DEBUG
 119         moveq   #67, %d7                /* 'C' */
 120         jsr     putc
 121 #endif /* DEBUG */
 122
 123         pea     0
 124         pea     env
 125         pea     %sp@(4)
 126         pea     0
 127
 128 #ifdef DEBUG
 129         moveq   #70, %d7                /* 'F' */
 130         jsr     putc
 131 #endif /* DEBUG */
 132
 133 lp:
 134         jsr     start_kernel
 135         jmp lp
 136 _exit:
 137
 138         jmp     _exit
 139
 140 __main:
 141         /* nothing */
 142         rts
 143
 144 #ifdef DEBUG
 145 putc:
 146         moveb   %d7,0xfffff907
 147 pclp:
 148         movew   0xfffff906, %d7
 149         andw    #0x2000, %d7
 150         beq     pclp
 151         rts
 152 #endif /* DEBUG */
 153
 154         .data
 155
 156 /*
 157  *      Set up the usable of RAM stuff. Size of RAM is determined then
 158  *      an initial stack set up at the end.
 159  */
 160 .align 4
 161 _ramvec:
 162 .long   0
 163 _rambase:
 164 .long   0
 165 _ramstart:
 166 .long   0
 167 _ramend:
 168 .long   0
 169
 170 env:
 171         .long   0