Rev 227 | Rev 317 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 1 | jermar | 1 | /* |
| 2 | * Copyright (C) 2001-2004 Jakub Jermar |
||
| 3 | * All rights reserved. |
||
| 4 | * |
||
| 5 | * Redistribution and use in source and binary forms, with or without |
||
| 6 | * modification, are permitted provided that the following conditions |
||
| 7 | * are met: |
||
| 8 | * |
||
| 9 | * - Redistributions of source code must retain the above copyright |
||
| 10 | * notice, this list of conditions and the following disclaimer. |
||
| 11 | * - Redistributions in binary form must reproduce the above copyright |
||
| 12 | * notice, this list of conditions and the following disclaimer in the |
||
| 13 | * documentation and/or other materials provided with the distribution. |
||
| 14 | * - The name of the author may not be used to endorse or promote products |
||
| 15 | * derived from this software without specific prior written permission. |
||
| 16 | * |
||
| 17 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
||
| 18 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||
| 19 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
||
| 20 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
||
| 21 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||
| 22 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
||
| 23 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
||
| 24 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
||
| 25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
||
| 26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||
| 27 | */ |
||
| 28 | |||
| 29 | #include <arch/exception.h> |
||
| 195 | vana | 30 | #include <arch/interrupt.h> |
| 1 | jermar | 31 | #include <panic.h> |
| 32 | #include <arch/cp0.h> |
||
| 33 | #include <arch/types.h> |
||
| 34 | #include <arch.h> |
||
| 227 | jermar | 35 | #include <debug.h> |
| 1 | jermar | 36 | |
| 37 | void exception(void) |
||
| 38 | { |
||
| 39 | int excno; |
||
| 40 | __u32 epc; |
||
| 123 | decky | 41 | __u32 epc_shift = 0; |
| 213 | jermar | 42 | |
| 227 | jermar | 43 | ASSERT(CPU != NULL); |
| 44 | |||
| 213 | jermar | 45 | /* |
| 46 | * NOTE ON OPERATION ORDERING |
||
| 47 | * |
||
| 48 | * On entry, cpu_priority_high() must be called before exception bit is cleared. |
||
| 49 | * On exit, exception bit must be set before cpu_priority_restore() is called. |
||
| 50 | */ |
||
| 51 | |||
| 313 | palkovsky | 52 | cpu_priority_high(); |
| 1 | jermar | 53 | epc = cp0_epc_read(); |
| 313 | palkovsky | 54 | cp0_status_write(cp0_status_read() & ~ (cp0_status_exl_exception_bit | |
| 55 | cp0_status_um_bit)); |
||
| 1 | jermar | 56 | |
| 15 | jermar | 57 | if (THREAD) { |
| 58 | THREAD->saved_epc = epc; |
||
| 1 | jermar | 59 | } |
| 60 | /* decode exception number and process the exception */ |
||
| 123 | decky | 61 | switch (excno = (cp0_cause_read() >> 2) & 0x1f) { |
| 62 | case EXC_Int: |
||
| 63 | interrupt(); |
||
| 64 | break; |
||
| 1 | jermar | 65 | case EXC_TLBL: |
| 123 | decky | 66 | case EXC_TLBS: |
| 67 | tlb_invalid(); |
||
| 68 | break; |
||
| 69 | case EXC_Mod: |
||
| 70 | panic("unhandled TLB Modification Exception\n"); |
||
| 71 | break; |
||
| 72 | case EXC_AdEL: |
||
| 73 | panic("unhandled Address Error Exception - load or instruction fetch\n"); |
||
| 74 | break; |
||
| 75 | case EXC_AdES: |
||
| 76 | panic("unhandled Address Error Exception - store\n"); |
||
| 77 | break; |
||
| 78 | case EXC_IBE: |
||
| 79 | panic("unhandled Bus Error Exception - fetch instruction\n"); |
||
| 80 | break; |
||
| 81 | case EXC_DBE: |
||
| 82 | panic("unhandled Bus Error Exception - data reference: load or store\n"); |
||
| 83 | break; |
||
| 84 | case EXC_Bp: |
||
| 85 | /* it is necessary to not re-execute BREAK instruction after returning from Exception handler |
||
| 86 | (see page 138 in R4000 Manual for more information) */ |
||
| 87 | epc_shift = 4; |
||
| 88 | break; |
||
| 89 | case EXC_RI: |
||
| 90 | panic("unhandled Reserved Instruction Exception\n"); |
||
| 91 | break; |
||
| 92 | case EXC_CpU: |
||
| 93 | panic("unhandled Coprocessor Unusable Exception\n"); |
||
| 94 | break; |
||
| 95 | case EXC_Ov: |
||
| 96 | panic("unhandled Arithmetic Overflow Exception\n"); |
||
| 97 | break; |
||
| 98 | case EXC_Tr: |
||
| 99 | panic("unhandled Trap Exception\n"); |
||
| 100 | break; |
||
| 101 | case EXC_VCEI: |
||
| 102 | panic("unhandled Virtual Coherency Exception - instruction\n"); |
||
| 103 | break; |
||
| 104 | case EXC_FPE: |
||
| 105 | panic("unhandled Floating-Point Exception\n"); |
||
| 106 | break; |
||
| 107 | case EXC_WATCH: |
||
| 108 | panic("unhandled reference to WatchHi/WatchLo address\n"); |
||
| 109 | break; |
||
| 110 | case EXC_VCED: |
||
| 111 | panic("unhandled Virtual Coherency Exception - data\n"); |
||
| 112 | break; |
||
| 113 | default: |
||
| 114 | panic("unhandled exception %d\n", excno); |
||
| 1 | jermar | 115 | } |
| 116 | |||
| 313 | palkovsky | 117 | if (THREAD) |
| 15 | jermar | 118 | epc = THREAD->saved_epc; |
| 313 | palkovsky | 119 | |
| 120 | /* Raise EXL bit before epc_write, so that we support |
||
| 121 | * properly nested exceptions |
||
| 122 | */ |
||
| 123 | cp0_status_write(cp0_status_read() | cp0_status_exl_exception_bit); |
||
| 123 | decky | 124 | cp0_epc_write(epc + epc_shift); |
| 1 | jermar | 125 | } |