1 // See LICENSE for license details.
11 #include "gdbserver.h"
24 processor_t::processor_t(const char* isa
, sim_t
* sim
, uint32_t id
)
25 : debug(false), sim(sim
), ext(NULL
), disassembler(new disassembler_t
),
28 parse_isa_string(isa
);
30 mmu
= new mmu_t(sim
, this);
34 register_base_instructions();
37 processor_t::~processor_t()
39 #ifdef RISCV_ENABLE_HISTOGRAM
40 if (histogram_enabled
)
42 fprintf(stderr
, "PC Histogram size:%zu\n", pc_histogram
.size());
43 for (auto it
: pc_histogram
)
44 fprintf(stderr
, "%0" PRIx64
" %" PRIu64
"\n", it
.first
, it
.second
);
52 static void bad_isa_string(const char* isa
)
54 fprintf(stderr
, "error: bad --isa option %s\n", isa
);
58 void processor_t::parse_isa_string(const char* str
)
60 std::string lowercase
, tmp
;
61 for (const char *r
= str
; *r
; r
++)
62 lowercase
+= std::tolower(*r
);
64 const char* p
= lowercase
.c_str();
65 const char* all_subsets
= "imafdc";
70 if (strncmp(p
, "rv32", 4) == 0)
71 max_xlen
= 32, isa
= reg_t(1) << 30, p
+= 4;
72 else if (strncmp(p
, "rv64", 4) == 0)
74 else if (strncmp(p
, "rv", 2) == 0)
79 } else if (*p
== 'g') { // treat "G" as "IMAFD"
80 tmp
= std::string("imafd") + (p
+1);
82 } else if (*p
!= 'i') {
86 isa_string
= "rv" + std::to_string(max_xlen
) + p
;
87 isa
|= 1L << ('s' - 'a'); // advertise support for supervisor mode
90 isa
|= 1L << (*p
- 'a');
92 if (auto next
= strchr(all_subsets
, *p
)) {
93 all_subsets
= next
+ 1;
95 } else if (*p
== 'x') {
96 const char* ext
= p
+1, *end
= ext
;
99 register_extension(find_extension(std::string(ext
, end
- ext
).c_str())());
106 if (supports_extension('D') && !supports_extension('F'))
109 // advertise support for supervisor and user modes
110 isa
|= 1L << ('s' - 'a');
111 isa
|= 1L << ('u' - 'a');
114 void state_t::reset()
116 memset(this, 0, sizeof(*this));
119 mtvec
= DEFAULT_MTVEC
;
120 load_reservation
= -1;
123 void processor_t::set_debug(bool value
)
127 ext
->set_debug(value
);
130 void processor_t::set_histogram(bool value
)
132 histogram_enabled
= value
;
133 #ifndef RISCV_ENABLE_HISTOGRAM
135 fprintf(stderr
, "PC Histogram support has not been properly enabled;");
136 fprintf(stderr
, " please re-build the riscv-isa-run project using \"configure --enable-histogram\".\n");
141 void processor_t::reset(bool value
)
148 set_csr(CSR_MSTATUS
, state
.mstatus
);
151 ext
->reset(); // reset the extension
154 void processor_t::raise_interrupt(reg_t which
)
156 throw trap_t(((reg_t
)1 << (max_xlen
-1)) | which
);
159 static int ctz(reg_t val
)
163 while ((val
& 1) == 0)
168 void processor_t::take_interrupt()
170 reg_t pending_interrupts
= state
.mip
& state
.mie
;
172 reg_t mie
= get_field(state
.mstatus
, MSTATUS_MIE
);
173 reg_t m_enabled
= state
.prv
< PRV_M
|| (state
.prv
== PRV_M
&& mie
);
174 reg_t enabled_interrupts
= pending_interrupts
& ~state
.mideleg
& -m_enabled
;
176 reg_t sie
= get_field(state
.mstatus
, MSTATUS_SIE
);
177 reg_t s_enabled
= state
.prv
< PRV_S
|| (state
.prv
== PRV_S
&& sie
);
178 enabled_interrupts
|= pending_interrupts
& state
.mideleg
& -s_enabled
;
180 if (enabled_interrupts
)
181 raise_interrupt(ctz(enabled_interrupts
));
184 static bool validate_priv(reg_t priv
)
186 return priv
== PRV_U
|| priv
== PRV_S
|| priv
== PRV_M
;
189 void processor_t::set_privilege(reg_t prv
)
191 assert(validate_priv(prv
));
196 void processor_t::enter_debug_mode(uint8_t cause
)
198 fprintf(stderr
, "enter_debug_mode(%d)\n", cause
);
199 state
.dcsr
.cause
= cause
;
200 state
.dcsr
.prv
= state
.prv
;
202 state
.dpc
= state
.pc
;
203 state
.pc
= DEBUG_ROM_START
;
204 debug
= true; // TODO
207 void processor_t::take_trap(trap_t
& t
, reg_t epc
)
210 fprintf(stderr
, "core %3d: exception %s, epc 0x%016" PRIx64
"\n",
213 if (t
.cause() == CAUSE_BREAKPOINT
&&
214 sim
->gdbserver
&& sim
->gdbserver
->connected()) {
215 enter_debug_mode(DCSR_CAUSE_SWBP
);
219 // by default, trap to M-mode, unless delegated to S-mode
220 reg_t bit
= t
.cause();
221 reg_t deleg
= state
.medeleg
;
222 if (bit
& ((reg_t
)1 << (max_xlen
-1)))
223 deleg
= state
.mideleg
, bit
&= ~((reg_t
)1 << (max_xlen
-1));
224 if (state
.prv
<= PRV_S
&& bit
< max_xlen
&& ((deleg
>> bit
) & 1)) {
225 // handle the trap in S-mode
226 state
.pc
= state
.stvec
;
227 state
.scause
= t
.cause();
230 state
.sbadaddr
= t
.get_badaddr();
232 reg_t s
= state
.mstatus
;
233 s
= set_field(s
, MSTATUS_SPIE
, get_field(s
, MSTATUS_UIE
<< state
.prv
));
234 s
= set_field(s
, MSTATUS_SPP
, state
.prv
);
235 s
= set_field(s
, MSTATUS_SIE
, 0);
236 set_csr(CSR_MSTATUS
, s
);
237 set_privilege(PRV_S
);
239 if (state
.dcsr
.cause
) {
240 state
.pc
= DEBUG_ROM_EXCEPTION
;
242 state
.pc
= state
.mtvec
;
244 state
.mcause
= t
.cause();
247 state
.mbadaddr
= t
.get_badaddr();
249 reg_t s
= state
.mstatus
;
250 s
= set_field(s
, MSTATUS_MPIE
, get_field(s
, MSTATUS_UIE
<< state
.prv
));
251 s
= set_field(s
, MSTATUS_MPP
, state
.prv
);
252 s
= set_field(s
, MSTATUS_MIE
, 0);
253 set_csr(CSR_MSTATUS
, s
);
254 set_privilege(PRV_M
);
257 yield_load_reservation();
260 void processor_t::disasm(insn_t insn
)
262 uint64_t bits
= insn
.bits() & ((1ULL << (8 * insn_length(insn
.bits()))) - 1);
263 fprintf(stderr
, "core %3d: 0x%016" PRIx64
" (0x%08" PRIx64
") %s\n",
264 id
, state
.pc
, bits
, disassembler
->disassemble(insn
).c_str());
267 static bool validate_vm(int max_xlen
, reg_t vm
)
269 if (max_xlen
== 64 && (vm
== VM_SV39
|| vm
== VM_SV48
))
271 if (max_xlen
== 32 && vm
== VM_SV32
)
273 return vm
== VM_MBARE
;
276 void processor_t::set_csr(int which
, reg_t val
)
278 val
= zext_xlen(val
);
279 reg_t delegable_ints
= MIP_SSIP
| MIP_STIP
| MIP_SEIP
| (1 << IRQ_COP
);
280 reg_t all_ints
= delegable_ints
| MIP_MSIP
| MIP_MTIP
;
285 state
.fflags
= val
& (FSR_AEXC
>> FSR_AEXC_SHIFT
);
289 state
.frm
= val
& (FSR_RD
>> FSR_RD_SHIFT
);
293 state
.fflags
= (val
& FSR_AEXC
) >> FSR_AEXC_SHIFT
;
294 state
.frm
= (val
& FSR_RD
) >> FSR_RD_SHIFT
;
297 if ((val
^ state
.mstatus
) &
298 (MSTATUS_VM
| MSTATUS_MPP
| MSTATUS_MPRV
| MSTATUS_PUM
))
301 reg_t mask
= MSTATUS_SIE
| MSTATUS_SPIE
| MSTATUS_MIE
| MSTATUS_MPIE
302 | MSTATUS_SPP
| MSTATUS_FS
| MSTATUS_MPRV
| MSTATUS_PUM
303 | (ext
? MSTATUS_XS
: 0);
305 if (validate_vm(max_xlen
, get_field(val
, MSTATUS_VM
)))
307 if (validate_priv(get_field(val
, MSTATUS_MPP
)))
310 state
.mstatus
= (state
.mstatus
& ~mask
) | (val
& mask
);
312 bool dirty
= (state
.mstatus
& MSTATUS_FS
) == MSTATUS_FS
;
313 dirty
|= (state
.mstatus
& MSTATUS_XS
) == MSTATUS_XS
;
315 state
.mstatus
= set_field(state
.mstatus
, MSTATUS32_SD
, dirty
);
317 state
.mstatus
= set_field(state
.mstatus
, MSTATUS64_SD
, dirty
);
319 // spike supports the notion of xlen < max_xlen, but current priv spec
320 // doesn't provide a mechanism to run RV32 software on an RV64 machine
325 reg_t mask
= MIP_SSIP
| MIP_STIP
;
326 state
.mip
= (state
.mip
& ~mask
) | (val
& mask
);
330 state
.mie
= (state
.mie
& ~all_ints
) | (val
& all_ints
);
333 state
.mideleg
= (state
.mideleg
& ~delegable_ints
) | (val
& delegable_ints
);
337 #define DECLARE_CAUSE(name, value) mask |= 1ULL << (value);
338 #include "encoding.h"
340 state
.medeleg
= (state
.medeleg
& ~mask
) | (val
& mask
);
343 case CSR_MUCOUNTEREN
:
344 state
.mucounteren
= val
& 7;
346 case CSR_MSCOUNTEREN
:
347 state
.mscounteren
= val
& 7;
350 reg_t mask
= SSTATUS_SIE
| SSTATUS_SPIE
| SSTATUS_SPP
| SSTATUS_FS
351 | SSTATUS_XS
| SSTATUS_PUM
;
352 return set_csr(CSR_MSTATUS
, (state
.mstatus
& ~mask
) | (val
& mask
));
355 return set_csr(CSR_MIP
,
356 (state
.mip
& ~state
.mideleg
) | (val
& state
.mideleg
));
358 return set_csr(CSR_MIE
,
359 (state
.mie
& ~state
.mideleg
) | (val
& state
.mideleg
));
360 case CSR_SEPC
: state
.sepc
= val
; break;
361 case CSR_STVEC
: state
.stvec
= val
>> 2 << 2; break;
362 case CSR_SPTBR
: state
.sptbr
= val
; break;
363 case CSR_SSCRATCH
: state
.sscratch
= val
; break;
364 case CSR_SCAUSE
: state
.scause
= val
; break;
365 case CSR_SBADADDR
: state
.sbadaddr
= val
; break;
366 case CSR_MEPC
: state
.mepc
= val
; break;
367 case CSR_MTVEC
: state
.mtvec
= val
>> 2 << 2; break;
368 case CSR_MSCRATCH
: state
.mscratch
= val
; break;
369 case CSR_MCAUSE
: state
.mcause
= val
; break;
370 case CSR_MBADADDR
: state
.mbadaddr
= val
; break;
372 // TODO: Use get_field style
373 state
.dcsr
.prv
= (val
& DCSR_PRV_MASK
) >> DCSR_PRV_OFFSET
;
374 state
.dcsr
.step
= (val
& DCSR_STEP_MASK
) >> DCSR_STEP_OFFSET
;
375 // TODO: ndreset and fullreset
376 state
.dcsr
.ebreakm
= (val
& DCSR_EBREAKM_MASK
) >> DCSR_EBREAKM_OFFSET
;
377 state
.dcsr
.ebreakh
= (val
& DCSR_EBREAKH_MASK
) >> DCSR_EBREAKH_OFFSET
;
378 state
.dcsr
.ebreaks
= (val
& DCSR_EBREAKS_MASK
) >> DCSR_EBREAKS_OFFSET
;
379 state
.dcsr
.ebreaku
= (val
& DCSR_EBREAKU_MASK
) >> DCSR_EBREAKU_OFFSET
;
380 state
.dcsr
.halt
= (val
& DCSR_HALT_MASK
) >> DCSR_HALT_OFFSET
;
385 case DSCRATCH_ADDRESS
:
386 state
.dscratch
= val
;
391 reg_t
processor_t::get_csr(int which
)
397 if (!supports_extension('F'))
402 if (!supports_extension('F'))
407 if (!supports_extension('F'))
409 return (state
.fflags
<< FSR_AEXC_SHIFT
) | (state
.frm
<< FSR_RD_SHIFT
);
413 if ((state
.mucounteren
>> (which
& (xlen
-1))) & 1)
414 return get_csr(which
+ (CSR_MCYCLE
- CSR_CYCLE
));
419 if ((state
.mscounteren
>> (which
& (xlen
-1))) & 1)
420 return get_csr(which
+ (CSR_MCYCLE
- CSR_SCYCLE
));
422 case CSR_MUCOUNTEREN
: return state
.mucounteren
;
423 case CSR_MSCOUNTEREN
: return state
.mscounteren
;
424 case CSR_MUCYCLE_DELTA
: return 0;
425 case CSR_MUTIME_DELTA
: return 0;
426 case CSR_MUINSTRET_DELTA
: return 0;
427 case CSR_MSCYCLE_DELTA
: return 0;
428 case CSR_MSTIME_DELTA
: return 0;
429 case CSR_MSINSTRET_DELTA
: return 0;
430 case CSR_MUCYCLE_DELTAH
: if (xlen
> 32) break; else return 0;
431 case CSR_MUTIME_DELTAH
: if (xlen
> 32) break; else return 0;
432 case CSR_MUINSTRET_DELTAH
: if (xlen
> 32) break; else return 0;
433 case CSR_MSCYCLE_DELTAH
: if (xlen
> 32) break; else return 0;
434 case CSR_MSTIME_DELTAH
: if (xlen
> 32) break; else return 0;
435 case CSR_MSINSTRET_DELTAH
: if (xlen
> 32) break; else return 0;
436 case CSR_MCYCLE
: return state
.minstret
;
437 case CSR_MINSTRET
: return state
.minstret
;
438 case CSR_MCYCLEH
: if (xlen
> 32) break; else return state
.minstret
>> 32;
439 case CSR_MINSTRETH
: if (xlen
> 32) break; else return state
.minstret
>> 32;
441 reg_t mask
= SSTATUS_SIE
| SSTATUS_SPIE
| SSTATUS_SPP
| SSTATUS_FS
442 | SSTATUS_XS
| SSTATUS_PUM
;
443 reg_t sstatus
= state
.mstatus
& mask
;
444 if ((sstatus
& SSTATUS_FS
) == SSTATUS_FS
||
445 (sstatus
& SSTATUS_XS
) == SSTATUS_XS
)
446 sstatus
|= (xlen
== 32 ? SSTATUS32_SD
: SSTATUS64_SD
);
449 case CSR_SIP
: return state
.mip
& state
.mideleg
;
450 case CSR_SIE
: return state
.mie
& state
.mideleg
;
451 case CSR_SEPC
: return state
.sepc
;
452 case CSR_SBADADDR
: return state
.sbadaddr
;
453 case CSR_STVEC
: return state
.stvec
;
456 return state
.scause
| ((state
.scause
>> (max_xlen
-1)) << (xlen
-1));
458 case CSR_SPTBR
: return state
.sptbr
;
459 case CSR_SASID
: return 0;
460 case CSR_SSCRATCH
: return state
.sscratch
;
461 case CSR_MSTATUS
: return state
.mstatus
;
462 case CSR_MIP
: return state
.mip
;
463 case CSR_MIE
: return state
.mie
;
464 case CSR_MEPC
: return state
.mepc
;
465 case CSR_MSCRATCH
: return state
.mscratch
;
466 case CSR_MCAUSE
: return state
.mcause
;
467 case CSR_MBADADDR
: return state
.mbadaddr
;
468 case CSR_MISA
: return isa
;
469 case CSR_MARCHID
: return 0;
470 case CSR_MIMPID
: return 0;
471 case CSR_MVENDORID
: return 0;
472 case CSR_MHARTID
: return id
;
473 case CSR_MTVEC
: return state
.mtvec
;
474 case CSR_MEDELEG
: return state
.medeleg
;
475 case CSR_MIDELEG
: return state
.mideleg
;
479 (1 << DCSR_XDEBUGVER_OFFSET
) |
480 (0 << DCSR_HWBPCOUNT_OFFSET
) |
481 (0 << DCSR_NDRESET_OFFSET
) |
482 (0 << DCSR_FULLRESET_OFFSET
) |
483 (state
.dcsr
.prv
<< DCSR_PRV_OFFSET
) |
484 (state
.dcsr
.step
<< DCSR_STEP_OFFSET
) |
485 (sim
->debug_module
.get_interrupt(id
) << DCSR_DEBUGINT_OFFSET
) |
486 (0 << DCSR_STOPCYCLE_OFFSET
) |
487 (0 << DCSR_STOPTIME_OFFSET
) |
488 (state
.dcsr
.ebreakm
<< DCSR_EBREAKM_OFFSET
) |
489 (state
.dcsr
.ebreakh
<< DCSR_EBREAKH_OFFSET
) |
490 (state
.dcsr
.ebreaks
<< DCSR_EBREAKS_OFFSET
) |
491 (state
.dcsr
.ebreaku
<< DCSR_EBREAKU_OFFSET
) |
492 (state
.dcsr
.halt
<< DCSR_HALT_OFFSET
) |
493 (state
.dcsr
.cause
<< DCSR_CAUSE_OFFSET
);
498 case DSCRATCH_ADDRESS
:
499 return state
.dscratch
;
501 throw trap_illegal_instruction();
504 reg_t
illegal_instruction(processor_t
* p
, insn_t insn
, reg_t pc
)
506 throw trap_illegal_instruction();
509 insn_func_t
processor_t::decode_insn(insn_t insn
)
511 // look up opcode in hash table
512 size_t idx
= insn
.bits() % OPCODE_CACHE_SIZE
;
513 insn_desc_t desc
= opcode_cache
[idx
];
515 if (unlikely(insn
.bits() != desc
.match
)) {
516 // fall back to linear search
517 insn_desc_t
* p
= &instructions
[0];
518 while ((insn
.bits() & p
->mask
) != p
->match
)
522 if (p
->mask
!= 0 && p
> &instructions
[0]) {
523 if (p
->match
!= (p
-1)->match
&& p
->match
!= (p
+1)->match
) {
524 // move to front of opcode list to reduce miss penalty
525 while (--p
>= &instructions
[0])
527 instructions
[0] = desc
;
531 opcode_cache
[idx
] = desc
;
532 opcode_cache
[idx
].match
= insn
.bits();
535 return xlen
== 64 ? desc
.rv64
: desc
.rv32
;
538 void processor_t::register_insn(insn_desc_t desc
)
540 instructions
.push_back(desc
);
543 void processor_t::build_opcode_map()
546 bool operator()(const insn_desc_t
& lhs
, const insn_desc_t
& rhs
) {
547 if (lhs
.match
== rhs
.match
)
548 return lhs
.mask
> rhs
.mask
;
549 return lhs
.match
> rhs
.match
;
552 std::sort(instructions
.begin(), instructions
.end(), cmp());
554 for (size_t i
= 0; i
< OPCODE_CACHE_SIZE
; i
++)
555 opcode_cache
[i
] = {1, 0, &illegal_instruction
, &illegal_instruction
};
558 void processor_t::register_extension(extension_t
* x
)
560 for (auto insn
: x
->get_instructions())
563 for (auto disasm_insn
: x
->get_disasms())
564 disassembler
->add_insn(disasm_insn
);
566 throw std::logic_error("only one extension may be registered");
568 x
->set_processor(this);
571 void processor_t::register_base_instructions()
573 #define DECLARE_INSN(name, match, mask) \
574 insn_bits_t name##_match = (match), name##_mask = (mask);
575 #include "encoding.h"
578 #define DEFINE_INSN(name) \
579 REGISTER_INSN(this, name, name##_match, name##_mask)
580 #include "insn_list.h"
583 register_insn({0, 0, &illegal_instruction
, &illegal_instruction
});
587 bool processor_t::load(reg_t addr
, size_t len
, uint8_t* bytes
)
592 bool processor_t::store(reg_t addr
, size_t len
, const uint8_t* bytes
)
597 state
.mip
&= ~MIP_MSIP
;
599 state
.mip
|= MIP_MSIP
;