| paul@68 | 1 | /* |
| paul@68 | 2 | * Handler routines. |
| paul@68 | 3 | * |
| paul@91 | 4 | * Copyright (C) 2015 Nicholas FitzRoy-Dale <wzdd.code@lardcave.net> |
| paul@110 | 5 | * Copyright (C) 2015, 2016 Paul Boddie <paul@boddie.org.uk> |
| paul@68 | 6 | * |
| paul@68 | 7 | * This program is free software: you can redistribute it and/or modify |
| paul@68 | 8 | * it under the terms of the GNU General Public License as published by |
| paul@68 | 9 | * the Free Software Foundation, either version 3 of the License, or |
| paul@68 | 10 | * (at your option) any later version. |
| paul@68 | 11 | * |
| paul@68 | 12 | * This program is distributed in the hope that it will be useful, |
| paul@68 | 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| paul@68 | 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| paul@68 | 15 | * GNU General Public License for more details. |
| paul@68 | 16 | * |
| paul@68 | 17 | * You should have received a copy of the GNU General Public License |
| paul@68 | 18 | * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| paul@68 | 19 | */ |
| paul@68 | 20 | |
| paul@68 | 21 | .text |
| paul@114 | 22 | .extern tlb_handle |
| paul@68 | 23 | .extern irq_handle |
| paul@133 | 24 | .extern current_stack_pointer |
| paul@133 | 25 | .extern current_task |
| paul@114 | 26 | .globl tlb_handler |
| paul@86 | 27 | .globl interrupt_handler |
| paul@68 | 28 | .set noreorder |
| paul@68 | 29 | .set noat |
| paul@68 | 30 | |
| paul@114 | 31 | tlb_handler: |
| paul@127 | 32 | /* gp should have been set in the entrypoint. */ |
| paul@127 | 33 | |
| paul@114 | 34 | jal save_state |
| paul@114 | 35 | nop |
| paul@114 | 36 | |
| paul@114 | 37 | /* Invoke the handler. */ |
| paul@114 | 38 | |
| paul@114 | 39 | jal tlb_handle |
| paul@114 | 40 | nop |
| paul@114 | 41 | |
| paul@114 | 42 | j load_and_return |
| paul@114 | 43 | nop |
| paul@114 | 44 | |
| paul@86 | 45 | interrupt_handler: |
| paul@127 | 46 | /* gp should have been set in the entrypoint. */ |
| paul@127 | 47 | |
| paul@114 | 48 | jal save_state |
| paul@114 | 49 | nop |
| paul@114 | 50 | |
| paul@133 | 51 | /* Record the stack pointer. */ |
| paul@133 | 52 | |
| paul@133 | 53 | la $k0, current_stack_pointer |
| paul@133 | 54 | sw $sp, 0($k0) |
| paul@133 | 55 | |
| paul@114 | 56 | /* Invoke the handler. */ |
| paul@114 | 57 | |
| paul@114 | 58 | jal irq_handle |
| paul@114 | 59 | nop |
| paul@114 | 60 | |
| paul@133 | 61 | /* Switch the stack pointer. */ |
| paul@133 | 62 | |
| paul@133 | 63 | la $k0, current_stack_pointer |
| paul@133 | 64 | lw $sp, 0($k0) |
| paul@133 | 65 | |
| paul@133 | 66 | /* Set the current task ASID. */ |
| paul@133 | 67 | |
| paul@133 | 68 | la $k0, current_task |
| paul@133 | 69 | lw $k1, 0($k0) |
| paul@133 | 70 | mtc0 $k1, $10 /* CP0_ENTRYHI */ |
| paul@133 | 71 | nop |
| paul@133 | 72 | |
| paul@114 | 73 | j load_and_return |
| paul@114 | 74 | nop |
| paul@114 | 75 | |
| paul@114 | 76 | save_state: |
| paul@86 | 77 | sw $at, -4($sp) |
| paul@86 | 78 | sw $v0, -8($sp) |
| paul@86 | 79 | sw $v1, -12($sp) |
| paul@86 | 80 | sw $a0, -16($sp) |
| paul@86 | 81 | sw $a1, -20($sp) |
| paul@86 | 82 | sw $a2, -24($sp) |
| paul@86 | 83 | sw $a3, -28($sp) |
| paul@86 | 84 | sw $t0, -32($sp) |
| paul@86 | 85 | sw $t1, -36($sp) |
| paul@86 | 86 | sw $t2, -40($sp) |
| paul@86 | 87 | sw $t3, -44($sp) |
| paul@86 | 88 | sw $t4, -48($sp) |
| paul@86 | 89 | sw $t5, -52($sp) |
| paul@86 | 90 | sw $t6, -56($sp) |
| paul@86 | 91 | sw $t7, -60($sp) |
| paul@86 | 92 | sw $s0, -64($sp) |
| paul@86 | 93 | sw $s1, -68($sp) |
| paul@86 | 94 | sw $s2, -72($sp) |
| paul@86 | 95 | sw $s3, -76($sp) |
| paul@86 | 96 | sw $s4, -80($sp) |
| paul@86 | 97 | sw $s5, -84($sp) |
| paul@86 | 98 | sw $s6, -88($sp) |
| paul@86 | 99 | sw $s7, -92($sp) |
| paul@86 | 100 | sw $t8, -96($sp) |
| paul@127 | 101 | /* sw $t9, -100($sp) */ |
| paul@127 | 102 | /* sw $gp, -104($sp) */ |
| paul@86 | 103 | sw $fp, -108($sp) |
| paul@114 | 104 | /* sw $ra, -112($sp) */ |
| paul@68 | 105 | |
| paul@110 | 106 | mfc0 $k0, $14 /* CP0_EPC */ |
| paul@110 | 107 | nop |
| paul@110 | 108 | sw $k0, -116($sp) |
| paul@110 | 109 | |
| paul@110 | 110 | addi $sp, $sp, -120 |
| paul@114 | 111 | j $ra |
| paul@114 | 112 | nop |
| paul@71 | 113 | |
| paul@114 | 114 | load_and_return: |
| paul@68 | 115 | |
| paul@110 | 116 | addi $sp, $sp, 120 |
| paul@68 | 117 | |
| paul@86 | 118 | lw $at, -4($sp) |
| paul@86 | 119 | lw $v0, -8($sp) |
| paul@86 | 120 | lw $v1, -12($sp) |
| paul@86 | 121 | lw $a0, -16($sp) |
| paul@86 | 122 | lw $a1, -20($sp) |
| paul@86 | 123 | lw $a2, -24($sp) |
| paul@86 | 124 | lw $a3, -28($sp) |
| paul@86 | 125 | lw $t0, -32($sp) |
| paul@86 | 126 | lw $t1, -36($sp) |
| paul@86 | 127 | lw $t2, -40($sp) |
| paul@86 | 128 | lw $t3, -44($sp) |
| paul@86 | 129 | lw $t4, -48($sp) |
| paul@86 | 130 | lw $t5, -52($sp) |
| paul@86 | 131 | lw $t6, -56($sp) |
| paul@86 | 132 | lw $t7, -60($sp) |
| paul@86 | 133 | lw $s0, -64($sp) |
| paul@86 | 134 | lw $s1, -68($sp) |
| paul@86 | 135 | lw $s2, -72($sp) |
| paul@86 | 136 | lw $s3, -76($sp) |
| paul@86 | 137 | lw $s4, -80($sp) |
| paul@86 | 138 | lw $s5, -84($sp) |
| paul@86 | 139 | lw $s6, -88($sp) |
| paul@86 | 140 | lw $s7, -92($sp) |
| paul@86 | 141 | lw $t8, -96($sp) |
| paul@86 | 142 | lw $t9, -100($sp) |
| paul@86 | 143 | lw $gp, -104($sp) |
| paul@86 | 144 | lw $fp, -108($sp) |
| paul@86 | 145 | lw $ra, -112($sp) |
| paul@86 | 146 | |
| paul@110 | 147 | lw $k0, -116($sp) |
| paul@110 | 148 | mtc0 $k0, $14 /* CP0_EPC */ |
| paul@110 | 149 | nop |
| paul@110 | 150 | |
| paul@110 | 151 | lw $k0, -120($sp) |
| paul@110 | 152 | mtc0 $k0, $12 /* CP0_STATUS */ |
| paul@110 | 153 | nop |
| paul@110 | 154 | |
| paul@86 | 155 | eret |
| paul@86 | 156 | nop |
| paul@68 | 157 | |
| paul@68 | 158 | .set reorder |
| paul@68 | 159 | .set at |
