debug/programs/trigger.S

   1 #include "../../env/encoding.h"
   2
   3 #undef MCONTROL_TYPE
   4 #undef MCONTROL_DMODE
   5 #ifdef __riscv64
   6 # define MCONTROL_TYPE    (0xf<<(64-4))
   7 # define MCONTROL_DMODE   (1<<(64-5))
   8 #else
   9 # define MCONTROL_TYPE    (0xf<<(32-4))
  10 # define MCONTROL_DMODE   (1<<(32-5))
  11 #endif
  12
  13         .global         main
  14
  15         .section        .text
  16 main:
  17
  18         la      a0, data
  19         li      t0, 0
  20 just_before_read_loop:
  21         li      t2, 16
  22 read_loop:
  23         lw      t1, 0(a0)
  24         addi    t0, t0, 1
  25         addi    a0, a0, 4
  26         blt     t0, t2, read_loop
  27
  28         la      a0, data
  29 just_before_write_loop:
  30         li      t0, 1
  31 write_loop:
  32         sw      t0, 0(a0)
  33         addi    t0, t0, 1
  34         addi    a0, a0, 4
  35         blt     t0, t2, write_loop
  36
  37         j       main_exit
  38
  39 write_valid:
  40         li      t0, 0
  41         li      t2, MCONTROL_DMODE
  42         li      t3, MCONTROL_TYPE
  43 write_valid_loop:
  44         csrw    CSR_TSELECT, t0
  45         csrr    t1, CSR_TSELECT
  46         bne     t0, t1, main_exit
  47         addi    t0, t0, 1
  48         csrr    t1, CSR_TDATA1
  49         and     t4, t1, t3
  50         beqz    t4, main_error  # type is 0
  51         and     t1, t1, t2
  52         bnez    t1, write_valid_loop
  53         # Found an entry with dmode=0
  54         csrw    CSR_TDATA1, zero        # this should succeed
  55
  56 write_invalid:
  57         li      t0, 0
  58         li      t2, MCONTROL_DMODE
  59         li      t3, MCONTROL_TYPE
  60 write_invalid_loop:
  61         csrw    CSR_TSELECT, t0
  62         csrr    t1, CSR_TSELECT
  63         bne     t0, t1, main_exit
  64         addi    t0, t0, 1
  65         csrr    t1, CSR_TDATA1
  66         and     t4, t1, t3
  67         beqz    t4, main_error  # type is 0
  68         and     t1, t1, t2
  69         beqz    t1, write_invalid_loop
  70         # Found an entry with dmode=1
  71 write_invalid_illegal:
  72         csrw    CSR_TDATA1, zero        # this should fail
  73
  74
  75 main_exit:
  76         li      a0, 0
  77         j       _exit
  78
  79 main_error:
  80         li      a0, 1
  81         j       _exit
  82
  83         .data
  84 data:   .word   0x40
  85         .word   0x41
  86         .word   0x42
  87         .word   0x43
  88         .word   0x44
  89         .word   0x45
  90         .word   0x46
  91         .word   0x47
  92         .word   0x48
  93         .word   0x49
  94         .word   0x4a
  95         .word   0x4b
  96         .word   0x4c
  97         .word   0x4d
  98         .word   0x4e
  99         .word   0x4f