isa.cc revision 8549
1/*
2 * Copyright (c) 2010 ARM Limited
3 * All rights reserved
4 *
5 * The license below extends only to copyright in the software and shall
6 * not be construed as granting a license to any other intellectual
7 * property including but not limited to intellectual property relating
8 * to a hardware implementation of the functionality of the software
9 * licensed hereunder.  You may use the software subject to the license
10 * terms below provided that you ensure that this notice is replicated
11 * unmodified and in its entirety in all distributions of the software,
12 * modified or unmodified, in source code or in binary form.
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions are
16 * met: redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer;
18 * redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution;
21 * neither the name of the copyright holders nor the names of its
22 * contributors may be used to endorse or promote products derived from
23 * this software without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
26 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
28 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
29 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
31 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
35 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 *
37 * Authors: Gabe Black
38 *          Ali Saidi
39 */
40
41#include "arch/arm/isa.hh"
42#include "debug/Arm.hh"
43#include "debug/MiscRegs.hh"
44#include "sim/faults.hh"
45#include "sim/stat_control.hh"
46#include "sim/system.hh"
47
48namespace ArmISA
49{
50
51void
52ISA::clear()
53{
54    SCTLR sctlr_rst = miscRegs[MISCREG_SCTLR_RST];
55    uint32_t midr = miscRegs[MISCREG_MIDR];
56    memset(miscRegs, 0, sizeof(miscRegs));
57    CPSR cpsr = 0;
58    cpsr.mode = MODE_USER;
59    miscRegs[MISCREG_CPSR] = cpsr;
60    updateRegMap(cpsr);
61
62    SCTLR sctlr = 0;
63    sctlr.te = (bool)sctlr_rst.te;
64    sctlr.nmfi = (bool)sctlr_rst.nmfi;
65    sctlr.v = (bool)sctlr_rst.v;
66    sctlr.u    = 1;
67    sctlr.xp = 1;
68    sctlr.rao2 = 1;
69    sctlr.rao3 = 1;
70    sctlr.rao4 = 1;
71    miscRegs[MISCREG_SCTLR] = sctlr;
72    miscRegs[MISCREG_SCTLR_RST] = sctlr_rst;
73
74    // Preserve MIDR accross reset
75    miscRegs[MISCREG_MIDR] = midr;
76
77    /* Start with an event in the mailbox */
78    miscRegs[MISCREG_SEV_MAILBOX] = 1;
79
80    // Separate Instruction and Data TLBs.
81    miscRegs[MISCREG_TLBTR] = 1;
82
83    MVFR0 mvfr0 = 0;
84    mvfr0.advSimdRegisters = 2;
85    mvfr0.singlePrecision = 2;
86    mvfr0.doublePrecision = 2;
87    mvfr0.vfpExceptionTrapping = 0;
88    mvfr0.divide = 1;
89    mvfr0.squareRoot = 1;
90    mvfr0.shortVectors = 1;
91    mvfr0.roundingModes = 1;
92    miscRegs[MISCREG_MVFR0] = mvfr0;
93
94    MVFR1 mvfr1 = 0;
95    mvfr1.flushToZero = 1;
96    mvfr1.defaultNaN = 1;
97    mvfr1.advSimdLoadStore = 1;
98    mvfr1.advSimdInteger = 1;
99    mvfr1.advSimdSinglePrecision = 1;
100    mvfr1.advSimdHalfPrecision = 1;
101    mvfr1.vfpHalfPrecision = 1;
102    miscRegs[MISCREG_MVFR1] = mvfr1;
103
104    miscRegs[MISCREG_MPIDR] = 0;
105
106    // Reset values of PRRR and NMRR are implementation dependent
107
108    miscRegs[MISCREG_PRRR] =
109        (1 << 19) | // 19
110        (0 << 18) | // 18
111        (0 << 17) | // 17
112        (1 << 16) | // 16
113        (2 << 14) | // 15:14
114        (0 << 12) | // 13:12
115        (2 << 10) | // 11:10
116        (2 << 8)  | // 9:8
117        (2 << 6)  | // 7:6
118        (2 << 4)  | // 5:4
119        (1 << 2)  | // 3:2
120        0;          // 1:0
121    miscRegs[MISCREG_NMRR] =
122        (1 << 30) | // 31:30
123        (0 << 26) | // 27:26
124        (0 << 24) | // 25:24
125        (3 << 22) | // 23:22
126        (2 << 20) | // 21:20
127        (0 << 18) | // 19:18
128        (0 << 16) | // 17:16
129        (1 << 14) | // 15:14
130        (0 << 12) | // 13:12
131        (2 << 10) | // 11:10
132        (0 << 8)  | // 9:8
133        (3 << 6)  | // 7:6
134        (2 << 4)  | // 5:4
135        (0 << 2)  | // 3:2
136        0;          // 1:0
137
138    miscRegs[MISCREG_CPACR] = 0;
139    miscRegs[MISCREG_FPSID] = 0x410430A0;
140
141    // See section B4.1.84 of ARM ARM
142    // All values are latest for ARMv7-A profile
143    miscRegs[MISCREG_ID_ISAR0] = 0x02101111;
144    miscRegs[MISCREG_ID_ISAR1] = 0x02112111;
145    miscRegs[MISCREG_ID_ISAR2] = 0x21232141;
146    miscRegs[MISCREG_ID_ISAR3] = 0x01112131;
147    miscRegs[MISCREG_ID_ISAR4] = 0x10010142;
148    miscRegs[MISCREG_ID_ISAR5] = 0x00000000;
149
150    //XXX We need to initialize the rest of the state.
151}
152
153MiscReg
154ISA::readMiscRegNoEffect(int misc_reg)
155{
156    assert(misc_reg < NumMiscRegs);
157
158    int flat_idx;
159    if (misc_reg == MISCREG_SPSR)
160        flat_idx = flattenMiscIndex(misc_reg);
161    else
162        flat_idx = misc_reg;
163    MiscReg val = miscRegs[flat_idx];
164
165    DPRINTF(MiscRegs, "Reading From misc reg %d (%d) : %#x\n",
166            misc_reg, flat_idx, val);
167    return val;
168}
169
170
171MiscReg
172ISA::readMiscReg(int misc_reg, ThreadContext *tc)
173{
174    if (misc_reg == MISCREG_CPSR) {
175        CPSR cpsr = miscRegs[misc_reg];
176        PCState pc = tc->pcState();
177        cpsr.j = pc.jazelle() ? 1 : 0;
178        cpsr.t = pc.thumb() ? 1 : 0;
179        return cpsr;
180    }
181    if (misc_reg >= MISCREG_CP15_UNIMP_START)
182        panic("Unimplemented CP15 register %s read.\n",
183              miscRegName[misc_reg]);
184
185    switch (misc_reg) {
186      case MISCREG_MPIDR:
187        return tc->cpuId();
188        break;
189      case MISCREG_ID_MMFR0:
190        return 0x03; // VMSAv7 support
191      case MISCREG_ID_MMFR2:
192        return 0x01230000; // no HW access | WFI stalling | ISB and DSB
193                           // | all TLB maintenance | no Harvard
194      case MISCREG_ID_MMFR3:
195        return 0xF0102211; // SuperSec | Coherent TLB | Bcast Maint |
196                           // BP Maint | Cache Maint Set/way | Cache Maint MVA
197      case MISCREG_CLIDR:
198        warn_once("The clidr register always reports 0 caches.\n");
199        warn_once("clidr LoUIS field of 0b001 to match current "
200                  "ARM implementations.\n");
201        return 0x00200000;
202      case MISCREG_CCSIDR:
203        warn_once("The ccsidr register isn't implemented and "
204                "always reads as 0.\n");
205        break;
206      case MISCREG_ID_PFR0:
207        warn("Returning thumbEE disabled for now since we don't support CP14"
208             "config registers and jumping to ThumbEE vectors\n");
209        return 0x0031; // !ThumbEE | !Jazelle | Thumb | ARM
210      case MISCREG_ID_PFR1:
211        warn("reading unimplmented register ID_PFR1");
212        return 0;
213      case MISCREG_CTR:
214        return 0x86468006; // V7, 64 byte cache line, load/exclusive is exact
215      case MISCREG_ACTLR:
216        warn("Not doing anything for miscreg ACTLR\n");
217        break;
218      case MISCREG_PMCR:
219      case MISCREG_PMCCNTR:
220      case MISCREG_PMSELR:
221        warn("Not doing anything for read to miscreg %s\n",
222                miscRegName[misc_reg]);
223        break;
224      case MISCREG_CPSR_Q:
225        panic("shouldn't be reading this register seperately\n");
226      case MISCREG_FPSCR_QC:
227        return readMiscRegNoEffect(MISCREG_FPSCR) & ~FpscrQcMask;
228      case MISCREG_FPSCR_EXC:
229        return readMiscRegNoEffect(MISCREG_FPSCR) & ~FpscrExcMask;
230      case MISCREG_L2CTLR:
231        // mostly unimplemented, just set NumCPUs field from sim and return
232        L2CTLR l2ctlr = 0;
233        // b00:1CPU to b11:4CPUs
234        l2ctlr.numCPUs = tc->getSystemPtr()->numContexts() - 1;
235        return l2ctlr;
236    }
237    return readMiscRegNoEffect(misc_reg);
238}
239
240void
241ISA::setMiscRegNoEffect(int misc_reg, const MiscReg &val)
242{
243    assert(misc_reg < NumMiscRegs);
244
245    int flat_idx;
246    if (misc_reg == MISCREG_SPSR)
247        flat_idx = flattenMiscIndex(misc_reg);
248    else
249        flat_idx = misc_reg;
250    miscRegs[flat_idx] = val;
251
252    DPRINTF(MiscRegs, "Writing to misc reg %d (%d) : %#x\n", misc_reg,
253            flat_idx, val);
254}
255
256void
257ISA::setMiscReg(int misc_reg, const MiscReg &val, ThreadContext *tc)
258{
259
260    MiscReg newVal = val;
261    int x;
262    System *sys;
263    ThreadContext *oc;
264
265    if (misc_reg == MISCREG_CPSR) {
266        updateRegMap(val);
267
268
269        CPSR old_cpsr = miscRegs[MISCREG_CPSR];
270        int old_mode = old_cpsr.mode;
271        CPSR cpsr = val;
272        if (old_mode != cpsr.mode) {
273            tc->getITBPtr()->invalidateMiscReg();
274            tc->getDTBPtr()->invalidateMiscReg();
275        }
276
277        DPRINTF(Arm, "Updating CPSR from %#x to %#x f:%d i:%d a:%d mode:%#x\n",
278                miscRegs[misc_reg], cpsr, cpsr.f, cpsr.i, cpsr.a, cpsr.mode);
279        PCState pc = tc->pcState();
280        pc.nextThumb(cpsr.t);
281        pc.nextJazelle(cpsr.j);
282        tc->pcState(pc);
283    } else if (misc_reg >= MISCREG_CP15_UNIMP_START &&
284        misc_reg < MISCREG_CP15_END) {
285        panic("Unimplemented CP15 register %s wrote with %#x.\n",
286              miscRegName[misc_reg], val);
287    } else {
288        switch (misc_reg) {
289          case MISCREG_CPACR:
290            {
291
292                const uint32_t ones = (uint32_t)(-1);
293                CPACR cpacrMask = 0;
294                // Only cp10, cp11, and ase are implemented, nothing else should
295                // be writable
296                cpacrMask.cp10 = ones;
297                cpacrMask.cp11 = ones;
298                cpacrMask.asedis = ones;
299                newVal &= cpacrMask;
300                DPRINTF(MiscRegs, "Writing misc reg %s: %#x\n",
301                        miscRegName[misc_reg], newVal);
302            }
303            break;
304          case MISCREG_CSSELR:
305            warn_once("The csselr register isn't implemented.\n");
306            return;
307          case MISCREG_FPSCR:
308            {
309                const uint32_t ones = (uint32_t)(-1);
310                FPSCR fpscrMask = 0;
311                fpscrMask.ioc = ones;
312                fpscrMask.dzc = ones;
313                fpscrMask.ofc = ones;
314                fpscrMask.ufc = ones;
315                fpscrMask.ixc = ones;
316                fpscrMask.idc = ones;
317                fpscrMask.len = ones;
318                fpscrMask.stride = ones;
319                fpscrMask.rMode = ones;
320                fpscrMask.fz = ones;
321                fpscrMask.dn = ones;
322                fpscrMask.ahp = ones;
323                fpscrMask.qc = ones;
324                fpscrMask.v = ones;
325                fpscrMask.c = ones;
326                fpscrMask.z = ones;
327                fpscrMask.n = ones;
328                newVal = (newVal & (uint32_t)fpscrMask) |
329                         (miscRegs[MISCREG_FPSCR] & ~(uint32_t)fpscrMask);
330            }
331            break;
332          case MISCREG_CPSR_Q:
333            {
334                assert(!(newVal & ~CpsrMaskQ));
335                newVal = miscRegs[MISCREG_CPSR] | newVal;
336                misc_reg = MISCREG_CPSR;
337            }
338            break;
339          case MISCREG_FPSCR_QC:
340            {
341                newVal = miscRegs[MISCREG_FPSCR] | (newVal & FpscrQcMask);
342                misc_reg = MISCREG_FPSCR;
343            }
344            break;
345          case MISCREG_FPSCR_EXC:
346            {
347                newVal = miscRegs[MISCREG_FPSCR] | (newVal & FpscrExcMask);
348                misc_reg = MISCREG_FPSCR;
349            }
350            break;
351          case MISCREG_FPEXC:
352            {
353                // vfpv3 architecture, section B.6.1 of DDI04068
354                // bit 29 - valid only if fpexc[31] is 0
355                const uint32_t fpexcMask = 0x60000000;
356                newVal = (newVal & fpexcMask) |
357                         (miscRegs[MISCREG_FPEXC] & ~fpexcMask);
358            }
359            break;
360          case MISCREG_SCTLR:
361            {
362                DPRINTF(MiscRegs, "Writing SCTLR: %#x\n", newVal);
363                SCTLR sctlr = miscRegs[MISCREG_SCTLR];
364                SCTLR new_sctlr = newVal;
365                new_sctlr.nmfi =  (bool)sctlr.nmfi;
366                miscRegs[MISCREG_SCTLR] = (MiscReg)new_sctlr;
367                tc->getITBPtr()->invalidateMiscReg();
368                tc->getDTBPtr()->invalidateMiscReg();
369
370                // Check if all CPUs are booted with caches enabled
371                // so we can stop enforcing coherency of some kernel
372                // structures manually.
373                sys = tc->getSystemPtr();
374                for (x = 0; x < sys->numContexts(); x++) {
375                    oc = sys->getThreadContext(x);
376                    SCTLR other_sctlr = oc->readMiscRegNoEffect(MISCREG_SCTLR);
377                    if (!other_sctlr.c && oc->status() != ThreadContext::Halted)
378                        return;
379                }
380
381                for (x = 0; x < sys->numContexts(); x++) {
382                    oc = sys->getThreadContext(x);
383                    oc->getDTBPtr()->allCpusCaching();
384                    oc->getITBPtr()->allCpusCaching();
385                }
386                return;
387            }
388          case MISCREG_TLBTR:
389          case MISCREG_MVFR0:
390          case MISCREG_MVFR1:
391          case MISCREG_MPIDR:
392          case MISCREG_FPSID:
393            return;
394          case MISCREG_TLBIALLIS:
395          case MISCREG_TLBIALL:
396            sys = tc->getSystemPtr();
397            for (x = 0; x < sys->numContexts(); x++) {
398                oc = sys->getThreadContext(x);
399                assert(oc->getITBPtr() && oc->getDTBPtr());
400                oc->getITBPtr()->flushAll();
401                oc->getDTBPtr()->flushAll();
402            }
403            return;
404          case MISCREG_ITLBIALL:
405            tc->getITBPtr()->flushAll();
406            return;
407          case MISCREG_DTLBIALL:
408            tc->getDTBPtr()->flushAll();
409            return;
410          case MISCREG_TLBIMVAIS:
411          case MISCREG_TLBIMVA:
412            sys = tc->getSystemPtr();
413            for (x = 0; x < sys->numContexts(); x++) {
414                oc = sys->getThreadContext(x);
415                assert(oc->getITBPtr() && oc->getDTBPtr());
416                oc->getITBPtr()->flushMvaAsid(mbits(newVal, 31, 12),
417                        bits(newVal, 7,0));
418                oc->getDTBPtr()->flushMvaAsid(mbits(newVal, 31, 12),
419                        bits(newVal, 7,0));
420            }
421            return;
422          case MISCREG_TLBIASIDIS:
423          case MISCREG_TLBIASID:
424            sys = tc->getSystemPtr();
425            for (x = 0; x < sys->numContexts(); x++) {
426                oc = sys->getThreadContext(x);
427                assert(oc->getITBPtr() && oc->getDTBPtr());
428                oc->getITBPtr()->flushAsid(bits(newVal, 7,0));
429                oc->getDTBPtr()->flushAsid(bits(newVal, 7,0));
430            }
431            return;
432          case MISCREG_TLBIMVAAIS:
433          case MISCREG_TLBIMVAA:
434            sys = tc->getSystemPtr();
435            for (x = 0; x < sys->numContexts(); x++) {
436                oc = sys->getThreadContext(x);
437                assert(oc->getITBPtr() && oc->getDTBPtr());
438                oc->getITBPtr()->flushMva(mbits(newVal, 31,12));
439                oc->getDTBPtr()->flushMva(mbits(newVal, 31,12));
440            }
441            return;
442          case MISCREG_ITLBIMVA:
443            tc->getITBPtr()->flushMvaAsid(mbits(newVal, 31, 12),
444                    bits(newVal, 7,0));
445            return;
446          case MISCREG_DTLBIMVA:
447            tc->getDTBPtr()->flushMvaAsid(mbits(newVal, 31, 12),
448                    bits(newVal, 7,0));
449            return;
450          case MISCREG_ITLBIASID:
451            tc->getITBPtr()->flushAsid(bits(newVal, 7,0));
452            return;
453          case MISCREG_DTLBIASID:
454            tc->getDTBPtr()->flushAsid(bits(newVal, 7,0));
455            return;
456          case MISCREG_ACTLR:
457            warn("Not doing anything for write of miscreg ACTLR\n");
458            break;
459          case MISCREG_PMCR:
460            {
461              // Performance counters not implemented.  Instead, interpret
462              //   a reset command to this register to reset the simulator
463              //   statistics.
464              // PMCR_E | PMCR_P | PMCR_C
465              const int ResetAndEnableCounters = 0x7;
466              if (newVal == ResetAndEnableCounters) {
467                  inform("Resetting all simobject stats\n");
468                  Stats::schedStatEvent(false, true);
469                  break;
470              }
471            }
472          case MISCREG_PMCCNTR:
473          case MISCREG_PMSELR:
474            warn("Not doing anything for write to miscreg %s\n",
475                    miscRegName[misc_reg]);
476            break;
477          case MISCREG_V2PCWPR:
478          case MISCREG_V2PCWPW:
479          case MISCREG_V2PCWUR:
480          case MISCREG_V2PCWUW:
481          case MISCREG_V2POWPR:
482          case MISCREG_V2POWPW:
483          case MISCREG_V2POWUR:
484          case MISCREG_V2POWUW:
485            {
486              RequestPtr req = new Request;
487              unsigned flags;
488              BaseTLB::Mode mode;
489              Fault fault;
490              switch(misc_reg) {
491                  case MISCREG_V2PCWPR:
492                      flags = TLB::MustBeOne;
493                      mode = BaseTLB::Read;
494                      break;
495                  case MISCREG_V2PCWPW:
496                      flags = TLB::MustBeOne;
497                      mode = BaseTLB::Write;
498                      break;
499                  case MISCREG_V2PCWUR:
500                      flags = TLB::MustBeOne | TLB::UserMode;
501                      mode = BaseTLB::Read;
502                      break;
503                  case MISCREG_V2PCWUW:
504                      flags = TLB::MustBeOne | TLB::UserMode;
505                      mode = BaseTLB::Write;
506                      break;
507                  default:
508                      panic("Security Extensions not implemented!");
509              }
510              warn("Translating via MISCREG in atomic mode! Fix Me!\n");
511              req->setVirt(0, val, 1, flags, tc->pcState().pc());
512              fault = tc->getDTBPtr()->translateAtomic(req, tc, mode);
513              if (fault == NoFault) {
514                  miscRegs[MISCREG_PAR] =
515                      (req->getPaddr() & 0xfffff000) |
516                      (tc->getDTBPtr()->getAttr() );
517                  DPRINTF(MiscRegs,
518                          "MISCREG: Translated addr 0x%08x: PAR: 0x%08x\n",
519                          val, miscRegs[MISCREG_PAR]);
520              }
521              else {
522                  // Set fault bit and FSR
523                  FSR fsr = miscRegs[MISCREG_DFSR];
524                  miscRegs[MISCREG_PAR] =
525                      (fsr.ext << 6) |
526                      (fsr.fsHigh << 5) |
527                      (fsr.fsLow << 1) |
528                      0x1; // F bit
529              }
530              return;
531            }
532          case MISCREG_CONTEXTIDR:
533          case MISCREG_PRRR:
534          case MISCREG_NMRR:
535          case MISCREG_DACR:
536            tc->getITBPtr()->invalidateMiscReg();
537            tc->getDTBPtr()->invalidateMiscReg();
538            break;
539          case MISCREG_CPSR_MODE:
540            // This miscreg is used by copy*Regs to set the CPSR mode
541            // without updating other CPSR variables. It's used to
542            // make sure the register map is in such a state that we can
543            // see all of the registers for the copy.
544            updateRegMap(val);
545            return;
546          case MISCREG_L2CTLR:
547            warn("miscreg L2CTLR (%s) written with %#x. ignored...\n",
548                 miscRegName[misc_reg], uint32_t(val));
549        }
550    }
551    setMiscRegNoEffect(misc_reg, newVal);
552}
553
554}
555