Rev 213 | Rev 313 | 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; |
1 | jermar | 42 | pri_t pri; |
213 | jermar | 43 | |
227 | jermar | 44 | ASSERT(CPU != NULL); |
45 | |||
213 | jermar | 46 | /* |
47 | * NOTE ON OPERATION ORDERING |
||
48 | * |
||
49 | * On entry, cpu_priority_high() must be called before exception bit is cleared. |
||
50 | * On exit, exception bit must be set before cpu_priority_restore() is called. |
||
51 | */ |
||
52 | |||
1 | jermar | 53 | pri = cpu_priority_high(); |
54 | epc = cp0_epc_read(); |
||
55 | cp0_status_write(cp0_status_read() & ~ cp0_status_exl_exception_bit); |
||
56 | |||
15 | jermar | 57 | if (THREAD) { |
58 | THREAD->saved_pri = pri; |
||
59 | THREAD->saved_epc = epc; |
||
1 | jermar | 60 | } |
61 | /* decode exception number and process the exception */ |
||
123 | decky | 62 | switch (excno = (cp0_cause_read() >> 2) & 0x1f) { |
63 | case EXC_Int: |
||
64 | interrupt(); |
||
65 | break; |
||
1 | jermar | 66 | case EXC_TLBL: |
123 | decky | 67 | case EXC_TLBS: |
68 | tlb_invalid(); |
||
69 | break; |
||
70 | case EXC_Mod: |
||
71 | panic("unhandled TLB Modification Exception\n"); |
||
72 | break; |
||
73 | case EXC_AdEL: |
||
74 | panic("unhandled Address Error Exception - load or instruction fetch\n"); |
||
75 | break; |
||
76 | case EXC_AdES: |
||
77 | panic("unhandled Address Error Exception - store\n"); |
||
78 | break; |
||
79 | case EXC_IBE: |
||
80 | panic("unhandled Bus Error Exception - fetch instruction\n"); |
||
81 | break; |
||
82 | case EXC_DBE: |
||
83 | panic("unhandled Bus Error Exception - data reference: load or store\n"); |
||
84 | break; |
||
85 | case EXC_Bp: |
||
86 | /* it is necessary to not re-execute BREAK instruction after returning from Exception handler |
||
87 | (see page 138 in R4000 Manual for more information) */ |
||
88 | epc_shift = 4; |
||
89 | break; |
||
90 | case EXC_RI: |
||
91 | panic("unhandled Reserved Instruction Exception\n"); |
||
92 | break; |
||
93 | case EXC_CpU: |
||
94 | panic("unhandled Coprocessor Unusable Exception\n"); |
||
95 | break; |
||
96 | case EXC_Ov: |
||
97 | panic("unhandled Arithmetic Overflow Exception\n"); |
||
98 | break; |
||
99 | case EXC_Tr: |
||
100 | panic("unhandled Trap Exception\n"); |
||
101 | break; |
||
102 | case EXC_VCEI: |
||
103 | panic("unhandled Virtual Coherency Exception - instruction\n"); |
||
104 | break; |
||
105 | case EXC_FPE: |
||
106 | panic("unhandled Floating-Point Exception\n"); |
||
107 | break; |
||
108 | case EXC_WATCH: |
||
109 | panic("unhandled reference to WatchHi/WatchLo address\n"); |
||
110 | break; |
||
111 | case EXC_VCED: |
||
112 | panic("unhandled Virtual Coherency Exception - data\n"); |
||
113 | break; |
||
114 | default: |
||
115 | panic("unhandled exception %d\n", excno); |
||
1 | jermar | 116 | } |
117 | |||
15 | jermar | 118 | if (THREAD) { |
119 | pri = THREAD->saved_pri; |
||
120 | epc = THREAD->saved_epc; |
||
1 | jermar | 121 | } |
122 | |||
123 | decky | 123 | cp0_epc_write(epc + epc_shift); |
1 | jermar | 124 | cp0_status_write(cp0_status_read() | cp0_status_exl_exception_bit); |
125 | cpu_priority_restore(pri); |
||
126 | } |