isa.cc revision 8059 
1/*
2 * Copyright (c) 2009 The Regents of The University of Michigan
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 are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * 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
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Gabe Black
29 */
30
31#include "arch/mips/isa.hh"
32#include "arch/mips/mt_constants.hh"
33#include "arch/mips/mt.hh"
34#include "arch/mips/pra_constants.hh"
35#include "base/bitfield.hh"
36#include "cpu/base.hh"
37#include "cpu/thread_context.hh"
38
39namespace MipsISA
40{
41
42std::string
43ISA::miscRegNames[NumMiscRegs] =
44{
45    "Index", "MVPControl", "MVPConf0", "MVPConf1", "", "", "", "",
46    "Random", "VPEControl", "VPEConf0", "VPEConf1",
47        "YQMask", "VPESchedule", "VPEScheFBack", "VPEOpt",
48    "EntryLo0", "TCStatus", "TCBind", "TCRestart",
49        "TCHalt", "TCContext", "TCSchedule", "TCScheFBack",
50    "EntryLo1", "", "", "", "", "", "", "",
51    "Context", "ContextConfig", "", "", "", "", "", "",
52    "PageMask", "PageGrain", "", "", "", "", "", "",
53    "Wired", "SRSConf0", "SRCConf1", "SRSConf2",
54        "SRSConf3", "SRSConf4", "", "",
55    "HWREna", "", "", "", "", "", "", "",
56    "BadVAddr", "", "", "", "", "", "", "",
57    "Count", "", "", "", "", "", "", "",
58    "EntryHi", "", "", "", "", "", "", "",
59    "Compare", "", "", "", "", "", "", "",
60    "Status", "IntCtl", "SRSCtl", "SRSMap", "", "", "", "",
61    "Cause", "", "", "", "", "", "", "",
62    "EPC", "", "", "", "", "", "", "",
63    "PRId", "EBase", "", "", "", "", "", "",
64    "Config", "Config1", "Config2", "Config3", "", "", "", "",
65    "LLAddr", "", "", "", "", "", "", "",
66    "WatchLo0", "WatchLo1", "WatchLo2", "WatchLo3",
67        "WatchLo4", "WatchLo5", "WatchLo6", "WatchLo7",
68    "WatchHi0", "WatchHi1", "WatchHi2", "WatchHi3",
69        "WatchHi4", "WatchHi5", "WatchHi6", "WatchHi7",
70    "XCContext64", "", "", "", "", "", "", "",
71    "", "", "", "", "", "", "", "",
72    "", "", "", "", "", "", "", "",
73    "Debug", "TraceControl1", "TraceControl2", "UserTraceData",
74        "TraceBPC", "", "", "",
75    "DEPC", "", "", "", "", "", "", "",
76    "PerfCnt0", "PerfCnt1", "PerfCnt2", "PerfCnt3",
77        "PerfCnt4", "PerfCnt5", "PerfCnt6", "PerfCnt7",
78    "ErrCtl", "", "", "", "", "", "", "",
79    "CacheErr0", "CacheErr1", "CacheErr2", "CacheErr3", "", "", "", "",
80    "TagLo0", "DataLo1", "TagLo2", "DataLo3",
81        "TagLo4", "DataLo5", "TagLo6", "DataLo7",
82    "TagHi0", "DataHi1", "TagHi2", "DataHi3",
83        "TagHi4", "DataHi5", "TagHi6", "DataHi7",
84    "ErrorEPC", "", "", "", "", "", "", "",
85    "DESAVE", "", "", "", "", "", "", "",
86    "LLFlag"
87};
88
89ISA::ISA()
90{
91    init();
92}
93
94void
95ISA::init()
96{
97    miscRegFile.resize(NumMiscRegs);
98    bankType.resize(NumMiscRegs);
99
100    for (int i=0; i < NumMiscRegs; i++) {
101        miscRegFile[i].resize(1);
102        bankType[i] = perProcessor;
103    }
104
105    miscRegFile_WriteMask.resize(NumMiscRegs);
106
107    for (int i = 0; i < NumMiscRegs; i++) {
108        miscRegFile_WriteMask[i].push_back(0);
109    }
110    clear(0);
111}
112
113void
114ISA::clear(unsigned tid_or_vpn)
115{
116    for(int i = 0; i < NumMiscRegs; i++) {
117        miscRegFile[i][tid_or_vpn] = 0;
118        miscRegFile_WriteMask[i][tid_or_vpn] = (long unsigned int)(-1);
119    }
120}
121
122void
123ISA::expandForMultithreading(ThreadID num_threads, unsigned num_vpes)
124{
125    // Initialize all Per-VPE regs
126    uint32_t per_vpe_regs[] = { MISCREG_VPE_CONTROL,
127                                MISCREG_VPE_CONF0, MISCREG_VPE_CONF1,
128                                MISCREG_YQMASK,
129                                MISCREG_VPE_SCHEDULE, MISCREG_VPE_SCHEFBACK,
130                                MISCREG_VPE_OPT, MISCREG_SRS_CONF0,
131                                MISCREG_SRS_CONF1, MISCREG_SRS_CONF2,
132                                MISCREG_SRS_CONF3, MISCREG_SRS_CONF4,
133                                MISCREG_EBASE
134                              };
135    uint32_t num_vpe_regs = sizeof(per_vpe_regs) / 4;
136    for (int i = 0; i < num_vpe_regs; i++) {
137        if (num_vpes > 1) {
138            miscRegFile[per_vpe_regs[i]].resize(num_vpes);
139        }
140        bankType[per_vpe_regs[i]] = perVirtProcessor;
141    }
142
143    // Initialize all Per-TC regs
144    uint32_t per_tc_regs[] = { MISCREG_STATUS,
145                               MISCREG_TC_STATUS, MISCREG_TC_BIND,
146                               MISCREG_TC_RESTART, MISCREG_TC_HALT,
147                               MISCREG_TC_CONTEXT, MISCREG_TC_SCHEDULE,
148                               MISCREG_TC_SCHEFBACK,
149                               MISCREG_DEBUG, MISCREG_LLADDR
150                             };
151    uint32_t num_tc_regs = sizeof(per_tc_regs) /  4;
152
153    for (int i = 0; i < num_tc_regs; i++) {
154        miscRegFile[per_tc_regs[i]].resize(num_threads);
155        bankType[per_tc_regs[i]] = perThreadContext;
156    }
157
158
159    if (num_vpes > 1) {
160        for (int i=1; i < num_vpes; i++) {
161            clear(i);
162        }
163    }
164
165}
166
167//@TODO: Use MIPS STYLE CONSTANTS (e.g. TCHALT_H instead of TCH_H)
168void
169ISA::reset(std::string core_name, ThreadID num_threads,
170                   unsigned num_vpes, BaseCPU *cpu)
171{
172    DPRINTF(MipsPRA, "Resetting CP0 State with %i TCs and %i VPEs\n",
173            num_threads, num_vpes);
174
175    MipsISA::CoreSpecific &cp = cpu->coreParams;
176
177    // Do Default CP0 initialization HERE
178
179    // Do Initialization for MT cores here (eventually use
180    // core_name parameter to toggle this initialization)
181    // ===================================================
182    DPRINTF(MipsPRA, "Initializing CP0 State.... ");
183
184    PRIdReg procId = readMiscRegNoEffect(MISCREG_PRID);
185    procId.coOp = cp.CP0_PRId_CompanyOptions;
186    procId.coId = cp.CP0_PRId_CompanyID;
187    procId.procId = cp.CP0_PRId_ProcessorID;
188    procId.rev = cp.CP0_PRId_Revision;
189    setMiscRegNoEffect(MISCREG_PRID, procId);
190
191    // Now, create Write Mask for ProcID register
192    MiscReg procIDMask = 0; // Read-Only register
193    replaceBits(procIDMask, 0, 32, 0);
194    setRegMask(MISCREG_PRID, procIDMask);
195
196    // Config
197    ConfigReg cfg = readMiscRegNoEffect(MISCREG_CONFIG);
198    cfg.be = cp.CP0_Config_BE;
199    cfg.at = cp.CP0_Config_AT;
200    cfg.ar = cp.CP0_Config_AR;
201    cfg.mt = cp.CP0_Config_MT;
202    cfg.vi = cp.CP0_Config_VI;
203    cfg.m = 1;
204    setMiscRegNoEffect(MISCREG_CONFIG, cfg);
205    // Now, create Write Mask for Config register
206    MiscReg cfg_Mask = 0x7FFF0007;
207    replaceBits(cfg_Mask, 0, 32, 0);
208    setRegMask(MISCREG_CONFIG, cfg_Mask);
209
210    // Config1
211    Config1Reg cfg1 = readMiscRegNoEffect(MISCREG_CONFIG1);
212    cfg1.mmuSize = cp.CP0_Config1_MMU;
213    cfg1.is = cp.CP0_Config1_IS;
214    cfg1.il = cp.CP0_Config1_IL;
215    cfg1.ia = cp.CP0_Config1_IA;
216    cfg1.ds = cp.CP0_Config1_DS;
217    cfg1.dl = cp.CP0_Config1_DL;
218    cfg1.da = cp.CP0_Config1_DA;
219    cfg1.fp = cp.CP0_Config1_FP;
220    cfg1.ep = cp.CP0_Config1_EP;
221    cfg1.wr = cp.CP0_Config1_WR;
222    cfg1.md = cp.CP0_Config1_MD;
223    cfg1.c2 = cp.CP0_Config1_C2;
224    cfg1.pc = cp.CP0_Config1_PC;
225    cfg1.m = cp.CP0_Config1_M;
226    setMiscRegNoEffect(MISCREG_CONFIG1, cfg1);
227    // Now, create Write Mask for Config register
228    MiscReg cfg1_Mask = 0; // Read Only Register
229    replaceBits(cfg1_Mask, 0, 32, 0);
230    setRegMask(MISCREG_CONFIG1, cfg1_Mask);
231
232    // Config2
233    Config2Reg cfg2 = readMiscRegNoEffect(MISCREG_CONFIG2);
234    cfg2.tu = cp.CP0_Config2_TU;
235    cfg2.ts = cp.CP0_Config2_TS;
236    cfg2.tl = cp.CP0_Config2_TL;
237    cfg2.ta = cp.CP0_Config2_TA;
238    cfg2.su = cp.CP0_Config2_SU;
239    cfg2.ss = cp.CP0_Config2_SS;
240    cfg2.sl = cp.CP0_Config2_SL;
241    cfg2.sa = cp.CP0_Config2_SA;
242    cfg2.m = cp.CP0_Config2_M;
243    setMiscRegNoEffect(MISCREG_CONFIG2, cfg2);
244    // Now, create Write Mask for Config register
245    MiscReg cfg2_Mask = 0x7000F000; // Read Only Register
246    replaceBits(cfg2_Mask, 0, 32, 0);
247    setRegMask(MISCREG_CONFIG2, cfg2_Mask);
248
249    // Config3
250    Config3Reg cfg3 = readMiscRegNoEffect(MISCREG_CONFIG3);
251    cfg3.dspp = cp.CP0_Config3_DSPP;
252    cfg3.lpa = cp.CP0_Config3_LPA;
253    cfg3.veic = cp.CP0_Config3_VEIC;
254    cfg3.vint = cp.CP0_Config3_VInt;
255    cfg3.sp = cp.CP0_Config3_SP;
256    cfg3.mt = cp.CP0_Config3_MT;
257    cfg3.sm = cp.CP0_Config3_SM;
258    cfg3.tl = cp.CP0_Config3_TL;
259    setMiscRegNoEffect(MISCREG_CONFIG3, cfg3);
260    // Now, create Write Mask for Config register
261    MiscReg cfg3_Mask = 0; // Read Only Register
262    replaceBits(cfg3_Mask, 0, 32, 0);
263    setRegMask(MISCREG_CONFIG3, cfg3_Mask);
264
265    // EBase - CPUNum
266    EBaseReg eBase = readMiscRegNoEffect(MISCREG_EBASE);
267    eBase.cpuNum = cp.CP0_EBase_CPUNum;
268    replaceBits(eBase, 31, 31, 1);
269    setMiscRegNoEffect(MISCREG_EBASE, eBase);
270    // Now, create Write Mask for Config register
271    MiscReg EB_Mask = 0x3FFFF000;// Except Exception Base, the
272                                 // entire register is read only
273    replaceBits(EB_Mask, 0, 32, 0);
274    setRegMask(MISCREG_EBASE, EB_Mask);
275
276    // SRS Control - HSS (Highest Shadow Set)
277    SRSCtlReg scsCtl = readMiscRegNoEffect(MISCREG_SRSCTL);
278    scsCtl.hss = cp.CP0_SrsCtl_HSS;
279    setMiscRegNoEffect(MISCREG_SRSCTL, scsCtl);
280    // Now, create Write Mask for the SRS Ctl register
281    MiscReg SC_Mask = 0x0000F3C0;
282    replaceBits(SC_Mask, 0, 32, 0);
283    setRegMask(MISCREG_SRSCTL, SC_Mask);
284
285    // IntCtl - IPTI, IPPCI
286    IntCtlReg intCtl = readMiscRegNoEffect(MISCREG_INTCTL);
287    intCtl.ipti = cp.CP0_IntCtl_IPTI;
288    intCtl.ippci = cp.CP0_IntCtl_IPPCI;
289    setMiscRegNoEffect(MISCREG_INTCTL, intCtl);
290    // Now, create Write Mask for the IntCtl register
291    MiscReg IC_Mask = 0x000003E0;
292    replaceBits(IC_Mask, 0, 32, 0);
293    setRegMask(MISCREG_INTCTL, IC_Mask);
294
295    // Watch Hi - M - FIXME (More than 1 Watch register)
296    WatchHiReg watchHi = readMiscRegNoEffect(MISCREG_WATCHHI0);
297    watchHi.m = cp.CP0_WatchHi_M;
298    setMiscRegNoEffect(MISCREG_WATCHHI0, watchHi);
299    // Now, create Write Mask for the IntCtl register
300    MiscReg wh_Mask = 0x7FFF0FFF;
301    replaceBits(wh_Mask, 0, 32, 0);
302    setRegMask(MISCREG_WATCHHI0, wh_Mask);
303
304    // Perf Ctr - M - FIXME (More than 1 PerfCnt Pair)
305    PerfCntCtlReg perfCntCtl = readMiscRegNoEffect(MISCREG_PERFCNT0);
306    perfCntCtl.m = cp.CP0_PerfCtr_M;
307    perfCntCtl.w = cp.CP0_PerfCtr_W;
308    setMiscRegNoEffect(MISCREG_PERFCNT0, perfCntCtl);
309    // Now, create Write Mask for the IntCtl register
310    MiscReg pc_Mask = 0x00007FF;
311    replaceBits(pc_Mask, 0, 32, 0);
312    setRegMask(MISCREG_PERFCNT0, pc_Mask);
313
314    // Random
315    setMiscRegNoEffect(MISCREG_CP0_RANDOM, 63);
316    // Now, create Write Mask for the IntCtl register
317    MiscReg random_Mask = 0;
318    replaceBits(random_Mask, 0, 32, 0);
319    setRegMask(MISCREG_CP0_RANDOM, random_Mask);
320
321    // PageGrain
322    PageGrainReg pageGrain = readMiscRegNoEffect(MISCREG_PAGEGRAIN);
323    pageGrain.esp = cp.CP0_Config3_SP;
324    setMiscRegNoEffect(MISCREG_PAGEGRAIN, pageGrain);
325    // Now, create Write Mask for the IntCtl register
326    MiscReg pg_Mask = 0x10000000;
327    replaceBits(pg_Mask, 0, 32, 0);
328    setRegMask(MISCREG_PAGEGRAIN, pg_Mask);
329
330    // Status
331    StatusReg status = readMiscRegNoEffect(MISCREG_STATUS);
332    // Only CU0 and IE are modified on a reset - everything else needs
333    // to be controlled on a per CPU model basis
334
335    // Enable CP0 on reset
336    // status.cu0 = 1;
337
338    // Enable ERL bit on a reset
339    status.erl = 1;
340    // Enable BEV bit on a reset
341    status.bev = 1;
342
343    setMiscRegNoEffect(MISCREG_STATUS, status);
344    // Now, create Write Mask for the Status register
345    MiscReg stat_Mask = 0xFF78FF17;
346    replaceBits(stat_Mask, 0, 32, 0);
347    setRegMask(MISCREG_STATUS, stat_Mask);
348
349
350    // MVPConf0
351    MVPConf0Reg mvpConf0 = readMiscRegNoEffect(MISCREG_MVP_CONF0);
352    mvpConf0.tca = 1;
353    mvpConf0.pvpe = num_vpes - 1;
354    mvpConf0.ptc = num_threads - 1;
355    setMiscRegNoEffect(MISCREG_MVP_CONF0, mvpConf0);
356
357    // VPEConf0
358    VPEConf0Reg vpeConf0 = readMiscRegNoEffect(MISCREG_VPE_CONF0);
359    vpeConf0.mvp = 1;
360    setMiscRegNoEffect(MISCREG_VPE_CONF0, vpeConf0);
361
362    // TCBind
363    for (ThreadID tid = 0; tid < num_threads; tid++) {
364        TCBindReg tcBind = readMiscRegNoEffect(MISCREG_TC_BIND, tid);
365        tcBind.curTC = tid;
366        setMiscRegNoEffect(MISCREG_TC_BIND, tcBind, tid);
367    }
368    // TCHalt
369    TCHaltReg tcHalt = readMiscRegNoEffect(MISCREG_TC_HALT);
370    tcHalt.h = 0;
371    setMiscRegNoEffect(MISCREG_TC_HALT, tcHalt);
372
373    // TCStatus
374    // Set TCStatus Activated to 1 for the initial thread that is running
375    TCStatusReg tcStatus = readMiscRegNoEffect(MISCREG_TC_STATUS);
376    tcStatus.a = 1;
377    setMiscRegNoEffect(MISCREG_TC_STATUS, tcStatus);
378
379    // Set Dynamically Allocatable bit to 1 for all other threads
380    for (ThreadID tid = 1; tid < num_threads; tid++) {
381        tcStatus = readMiscRegNoEffect(MISCREG_TC_STATUS, tid);
382        tcStatus.da = 1;
383        setMiscRegNoEffect(MISCREG_TC_STATUS, tcStatus, tid);
384    }
385
386
387    MiscReg mask = 0x7FFFFFFF;
388
389    // Now, create Write Mask for the Index register
390    replaceBits(mask, 0, 32, 0);
391    setRegMask(MISCREG_INDEX, mask);
392
393    mask = 0x3FFFFFFF;
394    replaceBits(mask, 0, 32, 0);
395    setRegMask(MISCREG_ENTRYLO0, mask);
396    setRegMask(MISCREG_ENTRYLO1, mask);
397
398    mask = 0xFF800000;
399    replaceBits(mask, 0, 32, 0);
400    setRegMask(MISCREG_CONTEXT, mask);
401
402    mask = 0x1FFFF800;
403    replaceBits(mask, 0, 32, 0);
404    setRegMask(MISCREG_PAGEMASK, mask);
405
406    mask = 0x0;
407    replaceBits(mask, 0, 32, 0);
408    setRegMask(MISCREG_BADVADDR, mask);
409    setRegMask(MISCREG_LLADDR, mask);
410
411    mask = 0x08C00300;
412    replaceBits(mask, 0, 32, 0);
413    setRegMask(MISCREG_CAUSE, mask);
414
415}
416
417inline unsigned
418ISA::getVPENum(ThreadID tid)
419{
420    TCBindReg tcBind = miscRegFile[MISCREG_TC_BIND][tid];
421    return tcBind.curVPE;
422}
423
424MiscReg
425ISA::readMiscRegNoEffect(int misc_reg, ThreadID tid)
426{
427    unsigned reg_sel = (bankType[misc_reg] == perThreadContext)
428        ? tid : getVPENum(tid);
429    DPRINTF(MipsPRA, "Reading CP0 Register:%u Select:%u (%s) (%lx).\n",
430            misc_reg / 8, misc_reg % 8, miscRegNames[misc_reg],
431            miscRegFile[misc_reg][reg_sel]);
432    return miscRegFile[misc_reg][reg_sel];
433}
434
435//@TODO: MIPS MT's register view automatically connects
436//       Status to TCStatus depending on current thread
437//template <class TC>
438MiscReg
439ISA::readMiscReg(int misc_reg, ThreadContext *tc,  ThreadID tid)
440{
441    unsigned reg_sel = (bankType[misc_reg] == perThreadContext)
442        ? tid : getVPENum(tid);
443    DPRINTF(MipsPRA,
444            "Reading CP0 Register:%u Select:%u (%s) with effect (%lx).\n",
445            misc_reg / 8, misc_reg % 8, miscRegNames[misc_reg],
446            miscRegFile[misc_reg][reg_sel]);
447
448    return miscRegFile[misc_reg][reg_sel];
449}
450
451void
452ISA::setMiscRegNoEffect(int misc_reg, const MiscReg &val, ThreadID tid)
453{
454    unsigned reg_sel = (bankType[misc_reg] == perThreadContext)
455        ? tid : getVPENum(tid);
456    DPRINTF(MipsPRA,
457            "[tid:%i]: Setting (direct set) CP0 Register:%u "
458            "Select:%u (%s) to %#x.\n",
459            tid, misc_reg / 8, misc_reg % 8, miscRegNames[misc_reg], val);
460
461    miscRegFile[misc_reg][reg_sel] = val;
462}
463
464void
465ISA::setRegMask(int misc_reg, const MiscReg &val, ThreadID tid)
466{
467    unsigned reg_sel = (bankType[misc_reg] == perThreadContext)
468        ? tid : getVPENum(tid);
469    DPRINTF(MipsPRA,
470            "[tid:%i]: Setting CP0 Register: %u Select: %u (%s) to %#x\n",
471            tid, misc_reg / 8, misc_reg % 8, miscRegNames[misc_reg], val);
472    miscRegFile_WriteMask[misc_reg][reg_sel] = val;
473}
474
475// PROGRAMMER'S NOTES:
476// (1) Some CP0 Registers have fields that cannot
477// be overwritten. Make sure to handle those particular registers
478// with care!
479void
480ISA::setMiscReg(int misc_reg, const MiscReg &val,
481                    ThreadContext *tc, ThreadID tid)
482{
483    int reg_sel = (bankType[misc_reg] == perThreadContext)
484        ? tid : getVPENum(tid);
485
486    DPRINTF(MipsPRA,
487            "[tid:%i]: Setting CP0 Register:%u "
488            "Select:%u (%s) to %#x, with effect.\n",
489            tid, misc_reg / 8, misc_reg % 8, miscRegNames[misc_reg], val);
490
491    MiscReg cp0_val = filterCP0Write(misc_reg, reg_sel, val);
492
493    miscRegFile[misc_reg][reg_sel] = cp0_val;
494
495    scheduleCP0Update(tc->getCpuPtr(), 1);
496}
497
498/**
499 * This method doesn't need to adjust the Control Register Offset
500 * since it has already been done in the calling method
501 * (setRegWithEffect)
502*/
503MiscReg
504ISA::filterCP0Write(int misc_reg, int reg_sel, const MiscReg &val)
505{
506    MiscReg retVal = val;
507
508    // Mask off read-only regions
509    retVal &= miscRegFile_WriteMask[misc_reg][reg_sel];
510    MiscReg curVal = miscRegFile[misc_reg][reg_sel];
511    // Mask off current alue with inverse mask (clear writeable bits)
512    curVal &= (~miscRegFile_WriteMask[misc_reg][reg_sel]);
513    retVal |= curVal; // Combine the two
514    DPRINTF(MipsPRA,
515            "filterCP0Write: Mask: %lx, Inverse Mask: %lx, write Val: %x, "
516            "current val: %lx, written val: %x\n",
517            miscRegFile_WriteMask[misc_reg][reg_sel],
518            ~miscRegFile_WriteMask[misc_reg][reg_sel],
519            val, miscRegFile[misc_reg][reg_sel], retVal);
520    return retVal;
521}
522
523void
524ISA::scheduleCP0Update(BaseCPU *cpu, int delay)
525{
526    if (!cp0Updated) {
527        cp0Updated = true;
528
529        //schedule UPDATE
530        CP0Event *cp0_event = new CP0Event(this, cpu, UpdateCP0);
531        cpu->schedule(cp0_event, curTick() + cpu->ticks(delay));
532    }
533}
534
535void
536ISA::updateCPU(BaseCPU *cpu)
537{
538    ///////////////////////////////////////////////////////////////////
539    //
540    // EVALUATE CP0 STATE FOR MIPS MT
541    //
542    ///////////////////////////////////////////////////////////////////
543    MVPConf0Reg mvpConf0 = readMiscRegNoEffect(MISCREG_MVP_CONF0);
544    ThreadID num_threads = mvpConf0.ptc + 1;
545
546    for (ThreadID tid = 0; tid < num_threads; tid++) {
547        TCStatusReg tcStatus = readMiscRegNoEffect(MISCREG_TC_STATUS, tid);
548        TCHaltReg tcHalt = readMiscRegNoEffect(MISCREG_TC_HALT, tid);
549
550        //@todo: add vpe/mt check here thru mvpcontrol & vpecontrol regs
551        if (tcHalt.h == 1 || tcStatus.a == 0)  {
552            haltThread(cpu->getContext(tid));
553        } else if (tcHalt.h == 0 && tcStatus.a == 1) {
554            restoreThread(cpu->getContext(tid));
555        }
556    }
557
558    num_threads = mvpConf0.ptc + 1;
559
560    // Toggle update flag after we finished updating
561    cp0Updated = false;
562}
563
564ISA::CP0Event::CP0Event(CP0 *_cp0, BaseCPU *_cpu, CP0EventType e_type)
565    : Event(CPU_Tick_Pri), cp0(_cp0), cpu(_cpu), cp0EventType(e_type)
566{  }
567
568void
569ISA::CP0Event::process()
570{
571    switch (cp0EventType)
572    {
573      case UpdateCP0:
574        cp0->updateCPU(cpu);
575        break;
576    }
577}
578
579const char *
580ISA::CP0Event::description() const
581{
582    return "Coprocessor-0 event";
583}
584
585void
586ISA::CP0Event::scheduleEvent(int delay)
587{
588    cpu->reschedule(this, curTick() + cpu->ticks(delay), true);
589}
590
591void
592ISA::CP0Event::unscheduleEvent()
593{
594    if (scheduled())
595        squash();
596}
597
598}
599