1/*
2 * Copyright (c) 2003-2005 The Regents of The University of Michigan
3 * Copyright (c) 2007 MIPS Technologies, Inc.
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are
8 * met: redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer;
10 * redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution;
13 * neither the name of the copyright holders nor the names of its
14 * contributors may be used to endorse or promote products derived from
15 * this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
20 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
21 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
23 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 *
29 * Authors: Gabe Black
30 * Korey Sewell
31 * Jaidev Patwardhan
32 */
33
34#include "arch/mips/faults.hh"
35#include "arch/mips/pra_constants.hh"
36#include "base/trace.hh"
37#include "cpu/base.hh"
38#include "cpu/thread_context.hh"
39#include "debug/MipsPRA.hh"
40
41#if !FULL_SYSTEM
42#include "mem/page_table.hh"
43#include "sim/process.hh"
44#endif
45
46namespace MipsISA
47{
48
49typedef MipsFaultBase::FaultVals FaultVals;
50
51template <> FaultVals MipsFault<MachineCheckFault>::vals =
52 { "Machine Check", 0x0401 };
53
54template <> FaultVals MipsFault<ResetFault>::vals =
55#if FULL_SYSTEM
56 { "Reset Fault", 0xBFC00000};
57#else
58 { "Reset Fault", 0x001};
59#endif
60
61template <> FaultVals MipsFault<AddressErrorFault>::vals =
62 { "Address Error", 0x0180 };
63
64template <> FaultVals MipsFault<SystemCallFault>::vals =
65 { "Syscall", 0x0180 };
66
67template <> FaultVals MipsFault<CoprocessorUnusableFault>::vals =
68 { "Coprocessor Unusable Fault", 0x180 };
69
70template <> FaultVals MipsFault<ReservedInstructionFault>::vals =
71 { "Reserved Instruction Fault", 0x0180 };
72
73template <> FaultVals MipsFault<ThreadFault>::vals =
74 { "Thread Fault", 0x00F1 };
75
76template <> FaultVals MipsFault<IntegerOverflowFault>::vals =
77 { "Integer Overflow Exception", 0x180 };
78
79template <> FaultVals MipsFault<InterruptFault>::vals =
80 { "interrupt", 0x0180 };
81
82template <> FaultVals MipsFault<TrapFault>::vals =
83 { "Trap", 0x0180 };
84
85template <> FaultVals MipsFault<BreakpointFault>::vals =
86 { "Breakpoint", 0x0180 };
87
88template <> FaultVals MipsFault<TlbInvalidFault>::vals =
89 { "Invalid TLB Entry Exception", 0x0180 };
90
91template <> FaultVals MipsFault<TlbRefillFault>::vals =
92 { "TLB Refill Exception", 0x0180 };
93
94template <> FaultVals MipsFault<TLBModifiedFault>::vals =
95 { "TLB Modified Exception", 0x0180 };
96
97template <> FaultVals MipsFault<DspStateDisabledFault>::vals =
98 { "DSP Disabled Fault", 0x001a };
99
100void
101MipsFaultBase::setExceptionState(ThreadContext *tc, uint8_t excCode)
102{
103 // modify SRS Ctl - Save CSS, put ESS into CSS
104 StatusReg status = tc->readMiscReg(MISCREG_STATUS);
105 if (status.exl != 1 && status.bev != 1) {
106 // SRS Ctl is modified only if Status_EXL and Status_BEV are not set
107 SRSCtlReg srsCtl = tc->readMiscReg(MISCREG_SRSCTL);
108 srsCtl.pss = srsCtl.css;
109 srsCtl.css = srsCtl.ess;
110 tc->setMiscRegNoEffect(MISCREG_SRSCTL, srsCtl);
111 }
112
113 // set EXL bit (don't care if it is already set!)
114 status.exl = 1;
115 tc->setMiscRegNoEffect(MISCREG_STATUS, status);
116
117 // write EPC
118 PCState pc = tc->pcState();
119 DPRINTF(MipsPRA, "PC: %s\n", pc);
120 bool delay_slot = pc.pc() + sizeof(MachInst) != pc.npc();
121 tc->setMiscRegNoEffect(MISCREG_EPC,
122 pc.pc() - delay_slot ? sizeof(MachInst) : 0);
123
124 // Set Cause_EXCCODE field
125 CauseReg cause = tc->readMiscReg(MISCREG_CAUSE);
126 cause.excCode = excCode;
127 cause.bd = delay_slot ? 1 : 0;
128 cause.ce = 0;
129 tc->setMiscRegNoEffect(MISCREG_CAUSE, cause);
130}
131
132#if FULL_SYSTEM
133void
134MipsFaultBase::setHandlerPC(Addr HandlerBase, ThreadContext *tc)
135{
136 tc->setPC(HandlerBase);
137 tc->setNextPC(HandlerBase + sizeof(MachInst));
138 tc->setNextNPC(HandlerBase + 2 * sizeof(MachInst));
139}
140
141void
142IntegerOverflowFault::invoke(ThreadContext *tc, StaticInstPtr inst)
143{
144 DPRINTF(MipsPRA, "%s encountered.\n", name());
145 setExceptionState(tc, 0xC);
146
147 // Set new PC
148 Addr HandlerBase;
149 StatusReg status = tc->readMiscReg(MISCREG_STATUS);
150 // Here, the handler is dependent on BEV, which is not modified by
151 // setExceptionState()
152 if (!status.bev) {
153 // See MIPS ARM Vol 3, Revision 2, Page 38
154 HandlerBase = vect() + tc->readMiscReg(MISCREG_EBASE);
155 } else {
156 HandlerBase = 0xBFC00200;
157 }
158 setHandlerPC(HandlerBase, tc);
159}
160
161void
162TrapFault::invoke(ThreadContext *tc, StaticInstPtr inst)
163{
164 DPRINTF(MipsPRA, "%s encountered.\n", name());
165 setExceptionState(tc, 0xD);
166
167 // Set new PC
168 Addr HandlerBase;
169 // Offset 0x180 - General Exception Vector
170 HandlerBase = vect() + tc->readMiscReg(MISCREG_EBASE);
171 setHandlerPC(HandlerBase, tc);
172}
173
174void
175BreakpointFault::invoke(ThreadContext *tc, StaticInstPtr inst)
176{
177 setExceptionState(tc, 0x9);
178
179 // Set new PC
180 Addr HandlerBase;
181 // Offset 0x180 - General Exception Vector
182 HandlerBase = vect() + tc->readMiscReg(MISCREG_EBASE);
183 setHandlerPC(HandlerBase, tc);
184}
185
186void
187TlbInvalidFault::invoke(ThreadContext *tc, StaticInstPtr inst)
188{
189 DPRINTF(MipsPRA, "%s encountered.\n", name());
190 setExceptionState(tc, store ? 0x3 : 0x2);
191
192 tc->setMiscRegNoEffect(MISCREG_BADVADDR, badVAddr);
193 EntryHiReg entryHi = tc->readMiscReg(MISCREG_ENTRYHI);
194 entryHi.asid = entryHiAsid;
195 entryHi.vpn2 = entryHiVPN2;
196 entryHi.vpn2x = entryHiVPN2X;
197 tc->setMiscRegNoEffect(MISCREG_ENTRYHI, entryHi);
198
199 ContextReg context = tc->readMiscReg(MISCREG_CONTEXT);
200 context.badVPN2 = contextBadVPN2;
201 tc->setMiscRegNoEffect(MISCREG_CONTEXT, context);
202
203 // Set new PC
204 Addr HandlerBase;
205 // Offset 0x180 - General Exception Vector
206 HandlerBase = vect() + tc->readMiscReg(MISCREG_EBASE);
207 setHandlerPC(HandlerBase, tc);
208}
209
210void
211AddressErrorFault::invoke(ThreadContext *tc, StaticInstPtr inst)
212{
213 DPRINTF(MipsPRA, "%s encountered.\n", name());
214 setExceptionState(tc, store ? 0x5 : 0x4);
215 tc->setMiscRegNoEffect(MISCREG_BADVADDR, vaddr);
216
217 // Set new PC
218 Addr HandlerBase;
219 // Offset 0x180 - General Exception Vector
220 HandlerBase = vect() + tc->readMiscReg(MISCREG_EBASE);
221 setHandlerPC(HandlerBase, tc);
222}
223
224void
225TlbRefillFault::invoke(ThreadContext *tc, StaticInstPtr inst)
226{
227 DPRINTF(MipsPRA, "%s encountered (%x).\n", name(), MISCREG_BADVADDR);
228 setExceptionState(tc, store ? 0x3 : 0x2);
229
230 Addr HandlerBase;
231 tc->setMiscRegNoEffect(MISCREG_BADVADDR, badVAddr);
232 EntryHiReg entryHi = tc->readMiscReg(MISCREG_ENTRYHI);
233 entryHi.asid = entryHiAsid;
234 entryHi.vpn2 = entryHiVPN2;
235 entryHi.vpn2x = entryHiVPN2X;
236 tc->setMiscRegNoEffect(MISCREG_ENTRYHI, entryHi);
237 ContextReg context = tc->readMiscReg(MISCREG_CONTEXT);
238 context.badVPN2 = contextBadVPN2;
239 tc->setMiscRegNoEffect(MISCREG_CONTEXT, context);
240
241 StatusReg status = tc->readMiscReg(MISCREG_STATUS);
242 // Since handler depends on EXL bit, must check EXL bit before setting it!!
243 // See MIPS ARM Vol 3, Revision 2, Page 38
244 if (status.exl == 1) {
245 // Offset 0x180 - General Exception Vector
246 HandlerBase = vect() + tc->readMiscReg(MISCREG_EBASE);
247 } else {
248 // Offset 0x000
249 HandlerBase = tc->readMiscReg(MISCREG_EBASE);
250 }
251 setHandlerPC(HandlerBase, tc);
252}
253
254void
255TLBModifiedFault::invoke(ThreadContext *tc, StaticInstPtr inst)
256{
257 DPRINTF(MipsPRA, "%s encountered.\n", name());
258 tc->setMiscRegNoEffect(MISCREG_BADVADDR, badVAddr);
259 EntryHiReg entryHi = tc->readMiscReg(MISCREG_ENTRYHI);
260 entryHi.asid = entryHiAsid;
261 entryHi.vpn2 = entryHiVPN2;
262 entryHi.vpn2x = entryHiVPN2X;
263 tc->setMiscRegNoEffect(MISCREG_ENTRYHI, entryHi);
264
265 ContextReg context = tc->readMiscReg(MISCREG_CONTEXT);
266 context.badVPN2 = contextBadVPN2;
267 tc->setMiscRegNoEffect(MISCREG_CONTEXT, context);
268
269 // Set new PC
270 Addr HandlerBase;
271 // Offset 0x180 - General Exception Vector
272 HandlerBase = vect() + tc->readMiscReg(MISCREG_EBASE);
273 setExceptionState(tc, 0x1);
274 setHandlerPC(HandlerBase, tc);
275
276}
277
278void
279SystemCallFault::invoke(ThreadContext *tc, StaticInstPtr inst)
280{
281 DPRINTF(MipsPRA, "%s encountered.\n", name());
282 setExceptionState(tc, 0x8);
283
284 // Set new PC
285 Addr HandlerBase;
286 // Offset 0x180 - General Exception Vector
287 HandlerBase = vect() + tc->readMiscReg(MISCREG_EBASE);
288 setHandlerPC(HandlerBase, tc);
289}
290
291void
292InterruptFault::invoke(ThreadContext *tc, StaticInstPtr inst)
293{
294#if FULL_SYSTEM
295 DPRINTF(MipsPRA, "%s encountered.\n", name());
296 setExceptionState(tc, 0x0A);
297 Addr HandlerBase;
298
299 CauseReg cause = tc->readMiscRegNoEffect(MISCREG_CAUSE);
300 if (cause.iv) {
301 // Offset 200 for release 2
302 HandlerBase = 0x20 + vect() + tc->readMiscRegNoEffect(MISCREG_EBASE);
303 } else {
304 //Ofset at 180 for release 1
305 HandlerBase = vect() + tc->readMiscRegNoEffect(MISCREG_EBASE);
306 }
307
308 setHandlerPC(HandlerBase, tc);
309#endif
310}
311
312#endif // FULL_SYSTEM
313
314void
315ResetFault::invoke(ThreadContext *tc, StaticInstPtr inst)
316{
317#if FULL_SYSTEM
318 DPRINTF(MipsPRA, "%s encountered.\n", name());
319 /* All reset activity must be invoked from here */
320 tc->setPC(vect());
321 tc->setNextPC(vect() + sizeof(MachInst));
322 tc->setNextNPC(vect() + sizeof(MachInst) + sizeof(MachInst));
323 DPRINTF(MipsPRA, "ResetFault::invoke : PC set to %x", tc->readPC());
324#endif
325
326 // Set Coprocessor 1 (Floating Point) To Usable
327 StatusReg status = tc->readMiscRegNoEffect(MISCREG_STATUS);
328 status.cu.cu1 = 1;
329 tc->setMiscReg(MISCREG_STATUS, status);
330}
331
332void
333ReservedInstructionFault::invoke(ThreadContext *tc, StaticInstPtr inst)
334{
335#if FULL_SYSTEM
336 DPRINTF(MipsPRA, "%s encountered.\n", name());
337 setExceptionState(tc, 0x0A);
338 Addr HandlerBase;
339 // Offset 0x180 - General Exception Vector
340 HandlerBase = vect() + tc->readMiscRegNoEffect(MISCREG_EBASE);
341 setHandlerPC(HandlerBase, tc);
342#else
343 panic("%s encountered.\n", name());
344#endif
345}
346
347void
348ThreadFault::invoke(ThreadContext *tc, StaticInstPtr inst)
349{
350 DPRINTF(MipsPRA, "%s encountered.\n", name());
351 panic("%s encountered.\n", name());
352}
353
354void
355DspStateDisabledFault::invoke(ThreadContext *tc, StaticInstPtr inst)
356{
357 DPRINTF(MipsPRA, "%s encountered.\n", name());
358 panic("%s encountered.\n", name());
359}
360
361void
362CoprocessorUnusableFault::invoke(ThreadContext *tc, StaticInstPtr inst)
363{
364#if FULL_SYSTEM
365 DPRINTF(MipsPRA, "%s encountered.\n", name());
366 setExceptionState(tc, 0xb);
367 // The ID of the coprocessor causing the exception is stored in
368 // CoprocessorUnusableFault::coProcID
369 CauseReg cause = tc->readMiscReg(MISCREG_CAUSE);
370 cause.ce = coProcID;
371 tc->setMiscRegNoEffect(MISCREG_CAUSE, cause);
372
373 Addr HandlerBase;
374 // Offset 0x180 - General Exception Vector
375 HandlerBase = vect() + tc->readMiscReg(MISCREG_EBASE);
376 setHandlerPC(HandlerBase, tc);
377
378#else
379 warn("%s (CP%d) encountered.\n", name(), coProcID);
380#endif
381}
382
383} // namespace MipsISA
384