litex/soc/cores/cpu/vexriscv_smp/crt0.S

   1 .global main
   2 .global isr
   3 .global _start
   4
   5 .global smp_lottery_target
   6 .global smp_lottery_lock
   7 .global smp_lottery_args
   8 .global smp_slave
   9
  10 _start:
  11   j crt_init
  12   nop
  13   nop
  14   nop
  15   nop
  16   nop
  17   nop
  18   nop
  19
  20 .global  trap_entry
  21 trap_entry:
  22   sw x1,  - 1*4(sp)
  23   sw x5,  - 2*4(sp)
  24   sw x6,  - 3*4(sp)
  25   sw x7,  - 4*4(sp)
  26   sw x10, - 5*4(sp)
  27   sw x11, - 6*4(sp)
  28   sw x12, - 7*4(sp)
  29   sw x13, - 8*4(sp)
  30   sw x14, - 9*4(sp)
  31   sw x15, -10*4(sp)
  32   sw x16, -11*4(sp)
  33   sw x17, -12*4(sp)
  34   sw x28, -13*4(sp)
  35   sw x29, -14*4(sp)
  36   sw x30, -15*4(sp)
  37   sw x31, -16*4(sp)
  38   addi sp,sp,-16*4
  39   call isr
  40   lw x1 , 15*4(sp)
  41   lw x5,  14*4(sp)
  42   lw x6,  13*4(sp)
  43   lw x7,  12*4(sp)
  44   lw x10, 11*4(sp)
  45   lw x11, 10*4(sp)
  46   lw x12,  9*4(sp)
  47   lw x13,  8*4(sp)
  48   lw x14,  7*4(sp)
  49   lw x15,  6*4(sp)
  50   lw x16,  5*4(sp)
  51   lw x17,  4*4(sp)
  52   lw x28,  3*4(sp)
  53   lw x29,  2*4(sp)
  54   lw x30,  1*4(sp)
  55   lw x31,  0*4(sp)
  56   addi sp,sp,16*4
  57   mret
  58   .text
  59
  60 crt_init:
  61   la sp, _fstack + 4
  62   la a0, trap_entry
  63   csrw mtvec, a0
  64   sw x0, smp_lottery_lock, a1
  65
  66 data_init:
  67   la a0, _fdata
  68   la a1, _edata
  69   la a2, _fdata_rom
  70 data_loop:
  71   beq a0,a1,data_done
  72   lw a3,0(a2)
  73   sw a3,0(a0)
  74   add a0,a0,4
  75   add a2,a2,4
  76   j data_loop
  77 data_done:
  78
  79 smp_tyranny:
  80   csrr a0, mhartid
  81   beqz a0, bss_init
  82   call smp_slave
  83
  84
  85
  86 bss_init:
  87   la a0, _fbss
  88   la a1, _ebss
  89 bss_loop:
  90   beq a0,a1,bss_done
  91   sw zero,0(a0)
  92   add a0,a0,4
  93   j bss_loop
  94 bss_done:
  95
  96   call main
  97 infinit_loop:
  98   j infinit_loop
  99
 100
 101
 102 //Initialized to avoid having them set to zero by BSS clear
 103 .bss
 104   smp_lottery_target: .word 0
 105   smp_lottery_args:   .word 0; .word 0; .word 0
 106   smp_lottery_lock:   .word 0
 107