src/arch/arm/utility.hh

   1 /*
   2  * Copyright (c) 2010, 2012-2013, 2016-2019 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  * Copyright (c) 2003-2005 The Regents of The University of Michigan
  15  * Copyright (c) 2007-2008 The Florida State University
  16  * All rights reserved.
  17  *
  18  * Redistribution and use in source and binary forms, with or without
  19  * modification, are permitted provided that the following conditions are
  20  * met: redistributions of source code must retain the above copyright
  21  * notice, this list of conditions and the following disclaimer;
  22  * redistributions in binary form must reproduce the above copyright
  23  * notice, this list of conditions and the following disclaimer in the
  24  * documentation and/or other materials provided with the distribution;
  25  * neither the name of the copyright holders nor the names of its
  26  * contributors may be used to endorse or promote products derived from
  27  * this software without specific prior written permission.
  28  *
  29  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  30  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  31  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  32  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  33  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  34  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  35  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  36  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  37  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  38  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  39  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  40  *
  41  * Authors: Korey Sewell
  42  *          Stephen Hines
  43  */
  44
  45 #ifndef __ARCH_ARM_UTILITY_HH__
  46 #define __ARCH_ARM_UTILITY_HH__
  47
  48 #include "arch/arm/isa_traits.hh"
  49 #include "arch/arm/miscregs.hh"
  50 #include "arch/arm/types.hh"
  51 #include "base/logging.hh"
  52 #include "base/trace.hh"
  53 #include "base/types.hh"
  54 #include "cpu/static_inst.hh"
  55 #include "cpu/thread_context.hh"
  56
  57 class ArmSystem;
  58
  59 namespace ArmISA {
  60
  61 inline PCState
  62 buildRetPC(const PCState &curPC, const PCState &callPC)
  63 {
  64     PCState retPC = callPC;
  65     retPC.uEnd();
  66     return retPC;
  67 }
  68
  69 inline bool
  70 testPredicate(uint32_t nz, uint32_t c, uint32_t v, ConditionCode code)
  71 {
  72     bool n = (nz & 0x2);
  73     bool z = (nz & 0x1);
  74
  75     switch (code)
  76     {
  77         case COND_EQ: return  z;
  78         case COND_NE: return !z;
  79         case COND_CS: return  c;
  80         case COND_CC: return !c;
  81         case COND_MI: return  n;
  82         case COND_PL: return !n;
  83         case COND_VS: return  v;
  84         case COND_VC: return !v;
  85         case COND_HI: return  (c && !z);
  86         case COND_LS: return !(c && !z);
  87         case COND_GE: return !(n ^ v);
  88         case COND_LT: return  (n ^ v);
  89         case COND_GT: return !(n ^ v || z);
  90         case COND_LE: return  (n ^ v || z);
  91         case COND_AL: return true;
  92         case COND_UC: return true;
  93         default:
  94             panic("Unhandled predicate condition: %d\n", code);
  95     }
  96 }
  97
  98 /**
  99  * Function to insure ISA semantics about 0 registers.
 100  * @param tc The thread context.
 101  */
 102 template <class TC>
 103 void zeroRegisters(TC *tc);
 104
 105 inline void startupCPU(ThreadContext *tc, int cpuId)
 106 {
 107     tc->activate();
 108 }
 109
 110 void copyRegs(ThreadContext *src, ThreadContext *dest);
 111
 112 static inline void
 113 copyMiscRegs(ThreadContext *src, ThreadContext *dest)
 114 {
 115     panic("Copy Misc. Regs Not Implemented Yet\n");
 116 }
 117
 118 void initCPU(ThreadContext *tc, int cpuId);
 119
 120 /** Send an event (SEV) to a specific PE if there isn't
 121  * already a pending event */
 122 void sendEvent(ThreadContext *tc);
 123
 124 static inline bool
 125 inUserMode(CPSR cpsr)
 126 {
 127     return cpsr.mode == MODE_USER || cpsr.mode == MODE_EL0T;
 128 }
 129
 130 static inline bool
 131 inUserMode(ThreadContext *tc)
 132 {
 133     return inUserMode(tc->readMiscRegNoEffect(MISCREG_CPSR));
 134 }
 135
 136 static inline bool
 137 inPrivilegedMode(CPSR cpsr)
 138 {
 139     return !inUserMode(cpsr);
 140 }
 141
 142 static inline bool
 143 inPrivilegedMode(ThreadContext *tc)
 144 {
 145     return !inUserMode(tc);
 146 }
 147
 148 bool inAArch64(ThreadContext *tc);
 149
 150 static inline OperatingMode
 151 currOpMode(ThreadContext *tc)
 152 {
 153     CPSR cpsr = tc->readMiscReg(MISCREG_CPSR);
 154     return (OperatingMode) (uint8_t) cpsr.mode;
 155 }
 156
 157 static inline ExceptionLevel
 158 currEL(ThreadContext *tc)
 159 {
 160     return opModeToEL(currOpMode(tc));
 161 }
 162
 163 inline ExceptionLevel
 164 currEL(CPSR cpsr)
 165 {
 166     return opModeToEL((OperatingMode) (uint8_t)cpsr.mode);
 167 }
 168
 169 bool HaveSecureEL2Ext(ThreadContext *tc);
 170 bool IsSecureEL2Enabled(ThreadContext *tc);
 171 bool EL2Enabled(ThreadContext *tc);
 172
 173 /**
 174  * This function checks whether selected EL provided as an argument
 175  * is using the AArch32 ISA. This information might be unavailable
 176  * at the current EL status: it hence returns a pair of boolean values:
 177  * a first boolean, true if information is available (known),
 178  * and a second one, true if EL is using AArch32, false for AArch64.
 179  *
 180  * @param tc The thread context.
 181  * @param el The target exception level.
 182  * @retval known is FALSE for EL0 if the current Exception level
 183  *               is not EL0 and EL1 is using AArch64, since it cannot
 184  *               determine the state of EL0; TRUE otherwise.
 185  * @retval aarch32 is TRUE if the specified Exception level is using AArch32;
 186  *                 FALSE otherwise.
 187  */
 188 std::pair<bool, bool>
 189 ELUsingAArch32K(ThreadContext *tc, ExceptionLevel el);
 190
 191 bool ELIs32(ThreadContext *tc, ExceptionLevel el);
 192
 193 bool ELIs64(ThreadContext *tc, ExceptionLevel el);
 194
 195 /**
 196  * Returns true if the current exception level `el` is executing a Host OS or
 197  * an application of a Host OS (Armv8.1 Virtualization Host Extensions).
 198  */
 199 bool ELIsInHost(ThreadContext *tc, ExceptionLevel el);
 200
 201 bool isBigEndian64(ThreadContext *tc);
 202
 203 /**
 204  * badMode is checking if the execution mode provided as an argument is
 205  * valid and implemented for AArch32
 206  *
 207  * @param tc ThreadContext
 208  * @param mode OperatingMode to check
 209  * @return false if mode is valid and implemented, true otherwise
 210  */
 211 bool badMode32(ThreadContext *tc, OperatingMode mode);
 212
 213 /**
 214  * badMode is checking if the execution mode provided as an argument is
 215  * valid and implemented.
 216  *
 217  * @param tc ThreadContext
 218  * @param mode OperatingMode to check
 219  * @return false if mode is valid and implemented, true otherwise
 220  */
 221 bool badMode(ThreadContext *tc, OperatingMode mode);
 222
 223 static inline uint8_t
 224 itState(CPSR psr)
 225 {
 226     ITSTATE it = 0;
 227     it.top6 = psr.it2;
 228     it.bottom2 = psr.it1;
 229
 230     return (uint8_t)it;
 231 }
 232
 233 /**
 234  * Removes the tag from tagged addresses if that mode is enabled.
 235  * @param addr The address to be purified.
 236  * @param tc The thread context.
 237  * @param el The controlled exception level.
 238  * @return The purified address.
 239  */
 240 Addr purifyTaggedAddr(Addr addr, ThreadContext *tc, ExceptionLevel el,
 241                       TTBCR tcr);
 242 Addr purifyTaggedAddr(Addr addr, ThreadContext *tc, ExceptionLevel el);
 243
 244 static inline bool
 245 inSecureState(SCR scr, CPSR cpsr)
 246 {
 247     switch ((OperatingMode) (uint8_t) cpsr.mode) {
 248       case MODE_MON:
 249       case MODE_EL3T:
 250       case MODE_EL3H:
 251         return true;
 252       case MODE_HYP:
 253       case MODE_EL2T:
 254       case MODE_EL2H:
 255         return false;
 256       default:
 257         return !scr.ns;
 258     }
 259 }
 260
 261 bool inSecureState(ThreadContext *tc);
 262
 263 /**
 264  * Return TRUE if an Exception level below EL3 is in Secure state.
 265  * Differs from inSecureState in that it ignores the current EL
 266  * or Mode in considering security state.
 267  */
 268 inline bool isSecureBelowEL3(ThreadContext *tc);
 269
 270 bool longDescFormatInUse(ThreadContext *tc);
 271
 272 /** This helper function is either returing the value of
 273  * MPIDR_EL1 (by calling getMPIDR), or it is issuing a read
 274  * to VMPIDR_EL2 (as it happens in virtualized systems) */
 275 RegVal readMPIDR(ArmSystem *arm_sys, ThreadContext *tc);
 276
 277 /** This helper function is returing the value of MPIDR_EL1 */
 278 RegVal getMPIDR(ArmSystem *arm_sys, ThreadContext *tc);
 279
 280 static inline uint32_t
 281 mcrMrcIssBuild(bool isRead, uint32_t crm, IntRegIndex rt, uint32_t crn,
 282                uint32_t opc1, uint32_t opc2)
 283 {
 284     return (isRead <<  0) |
 285            (crm    <<  1) |
 286            (rt     <<  5) |
 287            (crn    << 10) |
 288            (opc1   << 14) |
 289            (opc2   << 17);
 290 }
 291
 292 static inline void
 293 mcrMrcIssExtract(uint32_t iss, bool &isRead, uint32_t &crm, IntRegIndex &rt,
 294                  uint32_t &crn, uint32_t &opc1, uint32_t &opc2)
 295 {
 296     isRead = (iss >>  0) & 0x1;
 297     crm    = (iss >>  1) & 0xF;
 298     rt     = (IntRegIndex) ((iss >>  5) & 0xF);
 299     crn    = (iss >> 10) & 0xF;
 300     opc1   = (iss >> 14) & 0x7;
 301     opc2   = (iss >> 17) & 0x7;
 302 }
 303
 304 static inline uint32_t
 305 mcrrMrrcIssBuild(bool isRead, uint32_t crm, IntRegIndex rt, IntRegIndex rt2,
 306                  uint32_t opc1)
 307 {
 308     return (isRead <<  0) |
 309            (crm    <<  1) |
 310            (rt     <<  5) |
 311            (rt2    << 10) |
 312            (opc1   << 16);
 313 }
 314
 315 static inline uint32_t
 316 msrMrs64IssBuild(bool isRead, uint32_t op0, uint32_t op1, uint32_t crn,
 317                  uint32_t crm, uint32_t op2, IntRegIndex rt)
 318 {
 319     return isRead |
 320         (crm << 1) |
 321         (rt << 5) |
 322         (crn << 10) |
 323         (op1 << 14) |
 324         (op2 << 17) |
 325         (op0 << 20);
 326 }
 327
 328 bool
 329 mcrMrc15TrapToHyp(const MiscRegIndex miscReg, ThreadContext *tc, uint32_t iss);
 330
 331 bool
 332 mcrMrc14TrapToHyp(const MiscRegIndex miscReg, HCR hcr, CPSR cpsr, SCR scr,
 333                   HDCR hdcr, HSTR hstr, HCPTR hcptr, uint32_t iss);
 334 bool
 335 mcrrMrrc15TrapToHyp(const MiscRegIndex miscReg, CPSR cpsr, SCR scr, HSTR hstr,
 336                     HCR hcr, uint32_t iss);
 337
 338 bool SPAlignmentCheckEnabled(ThreadContext* tc);
 339
 340 uint64_t getArgument(ThreadContext *tc, int &number, uint16_t size, bool fp);
 341
 342 void skipFunction(ThreadContext *tc);
 343
 344 inline void
 345 advancePC(PCState &pc, const StaticInstPtr &inst)
 346 {
 347     inst->advancePC(pc);
 348 }
 349
 350 Addr truncPage(Addr addr);
 351 Addr roundPage(Addr addr);
 352
 353 inline uint64_t
 354 getExecutingAsid(ThreadContext *tc)
 355 {
 356     return tc->readMiscReg(MISCREG_CONTEXTIDR);
 357 }
 358
 359 // Decodes the register index to access based on the fields used in a MSR
 360 // or MRS instruction
 361 bool
 362 decodeMrsMsrBankedReg(uint8_t sysM, bool r, bool &isIntReg, int &regIdx,
 363                       CPSR cpsr, SCR scr, NSACR nsacr,
 364                       bool checkSecurity = true);
 365
 366 // This wrapper function is used to turn the register index into a source
 367 // parameter for the instruction. See Operands.isa
 368 static inline int
 369 decodeMrsMsrBankedIntRegIndex(uint8_t sysM, bool r)
 370 {
 371     int  regIdx;
 372     bool isIntReg;
 373     bool validReg;
 374
 375     validReg = decodeMrsMsrBankedReg(sysM, r, isIntReg, regIdx, 0, 0, 0, false);
 376     return (validReg && isIntReg) ? regIdx : INTREG_DUMMY;
 377 }
 378
 379 /**
 380  * Returns the n. of PA bits corresponding to the specified encoding.
 381  */
 382 int decodePhysAddrRange64(uint8_t pa_enc);
 383
 384 /**
 385  * Returns the encoding corresponding to the specified n. of PA bits.
 386  */
 387 uint8_t encodePhysAddrRange64(int pa_size);
 388
 389 inline ByteOrder byteOrder(ThreadContext *tc)
 390 {
 391     return isBigEndian64(tc) ? BigEndianByteOrder : LittleEndianByteOrder;
 392 };
 393
 394 }
 395
 396 #endif