[367] | 1 | /* |
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| 2 | * hal_witch.S - CPU context switch function for TSAR-MIPS32 |
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| 3 | * |
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| 4 | * Author Alain Greiner (2016) |
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| 5 | * |
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| 6 | * Copyright (c) UPMC Sorbonne Universites |
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| 7 | * |
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| 8 | * This file is part of ALMOS-MKH. |
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| 9 | * |
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| 10 | * ALMOS-MKH.is free software; you can redistribute it and/or modify it |
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| 11 | * under the terms of the GNU General Public License as published by |
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| 12 | * the Free Software Foundation; version 2.0 of the License. |
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| 13 | * |
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| 14 | * ALMOS-MKH.is distributed in the hope that it will be useful, but |
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| 15 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 17 | * General Public License for more details. |
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| 18 | * |
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| 19 | * You should have received a copy of the GNU General Public License |
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| 20 | * along with ALMOS-MKH.; if not, write to the Free Software Foundation, |
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| 21 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
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| 22 | */ |
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| 23 | |
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| 24 | #--------------------------------------------------------------------------------- |
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| 25 | # This code makes the following assumptions: |
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| 26 | # - register $4 contains a pointer on the old thread context. |
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| 27 | # - register $5 contains a pointer on the new thread context. |
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| 28 | # When the switch is completed, it jumps to address contained in register $31 |
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| 29 | # of the new context. |
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| 30 | #--------------------------------------------------------------------------------- |
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| 31 | |
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| 32 | .section .text , "ax" , @progbits |
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| 33 | |
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| 34 | .ent hal_do_switch |
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| 35 | .globl hal_do_switch |
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| 36 | |
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| 37 | .set noat |
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| 38 | .set noreorder |
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| 39 | |
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| 40 | hal_do_switch: |
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| 41 | |
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| 42 | move $26, $4 /* $26 <= ctx_old */ |
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| 43 | |
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| 44 | mfc0 $27, $14 |
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| 45 | sw $27, 0*4($26) /* save c0_epc to slot 0 */ |
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| 46 | |
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| 47 | sw $1, 1*4($26) |
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| 48 | sw $2, 2*4($26) |
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| 49 | sw $3, 3*4($26) |
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| 50 | sw $4, 4*4($26) |
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| 51 | sw $5, 5*4($26) |
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| 52 | sw $6, 6*4($26) |
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| 53 | sw $7, 7*4($26) |
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| 54 | |
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| 55 | sw $8, 8*4($26) |
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| 56 | sw $9, 9*4($26) |
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| 57 | sw $10, 10*4($26) |
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| 58 | sw $11, 11*4($26) |
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| 59 | sw $12, 12*4($26) |
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| 60 | sw $13, 13*4($26) |
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| 61 | sw $14, 14*4($26) |
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| 62 | sw $15, 15*4($26) |
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| 63 | |
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| 64 | sw $16, 16*4($26) |
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| 65 | sw $17, 17*4($26) |
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| 66 | sw $18, 18*4($26) |
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| 67 | sw $19, 19*4($26) |
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| 68 | sw $20, 20*4($26) |
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| 69 | sw $21, 21*4($26) |
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| 70 | sw $22, 22*4($26) |
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| 71 | sw $23, 23*4($26) |
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| 72 | |
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| 73 | sw $24, 24*4($26) |
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| 74 | sw $25, 25*4($26) |
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| 75 | |
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| 76 | mfhi $27 |
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| 77 | sw $27, 26*4($26) /* save hi to slot 26 */ |
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| 78 | mflo $27 |
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| 79 | sw $27, 27*4($26) /* save lo to slot 27 */ |
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| 80 | |
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| 81 | sw $28, 28*4($26) |
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| 82 | sw $29, 29*4($26) |
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| 83 | sw $30, 30*4($26) |
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| 84 | sw $31, 31*4($26) |
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| 85 | |
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| 86 | mfc2 $27, $0 |
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| 87 | sw $27, 32*4($26) /* save c2_ptpr to slot 32 */ |
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| 88 | mfc2 $27, $1 |
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| 89 | sw $27, 33*4($26) /* save c2_mode to slot 33 */ |
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| 90 | |
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| 91 | mfc0 $27, $12 |
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| 92 | sw $27, 34*4($26) /* save c0_sr to slot 34 */ |
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| 93 | mfc0 $27, $4, 2 |
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| 94 | sw $27, 35*4($26) /* save c0_th to slot 35 */ |
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| 95 | |
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| 96 | sync |
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| 97 | |
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| 98 | move $26, $5 /* $26 <= ctx_new */ |
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| 99 | |
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| 100 | lw $27, 0*4($26) |
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| 101 | mtc0 $27, $14 /* restore C0_epc from slot 0 */ |
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| 102 | |
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| 103 | lw $1, 1*4($26) |
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| 104 | lw $2, 2*4($26) |
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| 105 | lw $3, 3*4($26) |
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| 106 | lw $4, 4*4($26) |
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| 107 | lw $5, 5*4($26) |
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| 108 | lw $6, 6*4($26) |
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| 109 | lw $7, 7*4($26) |
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| 110 | |
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| 111 | lw $8, 8*4($26) |
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| 112 | lw $9, 9*4($26) |
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| 113 | lw $10, 10*4($26) |
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| 114 | lw $11, 11*4($26) |
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| 115 | lw $12, 12*4($26) |
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| 116 | lw $13, 13*4($26) |
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| 117 | lw $14, 14*4($26) |
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| 118 | lw $15, 15*4($26) |
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| 119 | |
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| 120 | lw $16, 16*4($26) |
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| 121 | lw $17, 17*4($26) |
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| 122 | lw $18, 18*4($26) |
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| 123 | lw $19, 19*4($26) |
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| 124 | lw $20, 20*4($26) |
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| 125 | lw $21, 21*4($26) |
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| 126 | lw $22, 22*4($26) |
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| 127 | lw $23, 23*4($26) |
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| 128 | |
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| 129 | lw $24, 24*4($26) |
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| 130 | lw $25, 25*4($26) |
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| 131 | |
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| 132 | lw $27, 26*4($26) |
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| 133 | mthi $27 /* restore hi from slot 26 */ |
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| 134 | lw $27, 27*4($26) |
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| 135 | mtlo $27 /* restote lo from slot 27 */ |
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| 136 | |
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| 137 | lw $28, 28*4($26) |
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| 138 | lw $29, 29*4($26) |
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| 139 | lw $30, 30*4($26) |
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| 140 | lw $31, 31*4($26) |
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| 141 | |
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| 142 | lw $27, 32*4($26) |
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| 143 | mtc2 $27, $0 /* restore c2_ptpr from slot 32 */ |
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| 144 | lw $27, 33*4($26) |
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| 145 | mtc2 $27, $1 /* restore c2_mode from slot 33 */ |
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| 146 | |
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| 147 | lw $27, 34*4($26) |
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| 148 | mtc0 $27, $12 /* restore c0_sr from slot 34 */ |
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| 149 | lw $27, 35*4($26) |
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| 150 | mtc0 $27, $4, 2 /* restore co_th from slot 35 */ |
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| 151 | |
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| 152 | jr $31 /* return to caller */ |
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| 153 | nop |
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| 154 | |
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| 155 | .set reorder |
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| 156 | .set at |
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| 157 | |
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| 158 | .end hal_do_switch |
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| 159 | |
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