1 // See LICENSE for license details.
23 processor_t::processor_t(const char* isa
, sim_t
* sim
, uint32_t id
)
24 : sim(sim
), ext(NULL
), disassembler(new disassembler_t
),
25 id(id
), run(false), debug(false), halted(false), single_step(false)
27 parse_isa_string(isa
);
29 mmu
= new mmu_t(sim
, this);
33 register_base_instructions();
36 processor_t::~processor_t()
38 #ifdef RISCV_ENABLE_HISTOGRAM
39 if (histogram_enabled
)
41 fprintf(stderr
, "PC Histogram size:%zu\n", pc_histogram
.size());
42 for (auto it
: pc_histogram
)
43 fprintf(stderr
, "%0" PRIx64
" %" PRIu64
"\n", it
.first
, it
.second
);
51 static void bad_isa_string(const char* isa
)
53 fprintf(stderr
, "error: bad --isa option %s\n", isa
);
57 void processor_t::parse_isa_string(const char* str
)
59 std::string lowercase
, tmp
;
60 for (const char *r
= str
; *r
; r
++)
61 lowercase
+= std::tolower(*r
);
63 const char* p
= lowercase
.c_str();
64 const char* all_subsets
= "imafdc";
69 if (strncmp(p
, "rv32", 4) == 0)
70 max_xlen
= 32, isa
= reg_t(1) << 30, p
+= 4;
71 else if (strncmp(p
, "rv64", 4) == 0)
73 else if (strncmp(p
, "rv", 2) == 0)
78 } else if (*p
== 'g') { // treat "G" as "IMAFD"
79 tmp
= std::string("imafd") + (p
+1);
81 } else if (*p
!= 'i') {
85 isa_string
= "rv" + std::to_string(max_xlen
) + p
;
86 isa
|= 1L << ('s' - 'a'); // advertise support for supervisor mode
89 isa
|= 1L << (*p
- 'a');
91 if (auto next
= strchr(all_subsets
, *p
)) {
92 all_subsets
= next
+ 1;
94 } else if (*p
== 'x') {
95 const char* ext
= p
+1, *end
= ext
;
98 register_extension(find_extension(std::string(ext
, end
- ext
).c_str())());
105 if (supports_extension('D') && !supports_extension('F'))
108 // advertise support for supervisor and user modes
109 isa
|= 1L << ('s' - 'a');
110 isa
|= 1L << ('u' - 'a');
113 void state_t::reset()
115 memset(this, 0, sizeof(*this));
118 mtvec
= DEFAULT_MTVEC
;
119 load_reservation
= -1;
122 void processor_t::set_debug(bool value
)
126 ext
->set_debug(value
);
129 void processor_t::set_halted(bool value
, halt_reason_t reason
)
132 halt_reason
= reason
;
135 void processor_t::set_single_step(bool value
)
140 void processor_t::set_histogram(bool value
)
142 histogram_enabled
= value
;
143 #ifndef RISCV_ENABLE_HISTOGRAM
145 fprintf(stderr
, "PC Histogram support has not been properly enabled;");
146 fprintf(stderr
, " please re-build the riscv-isa-run project using \"configure --enable-histogram\".\n");
151 void processor_t::reset(bool value
)
158 set_csr(CSR_MSTATUS
, state
.mstatus
);
161 ext
->reset(); // reset the extension
164 void processor_t::raise_interrupt(reg_t which
)
166 throw trap_t(((reg_t
)1 << (max_xlen
-1)) | which
);
169 static int ctz(reg_t val
)
173 while ((val
& 1) == 0)
178 void processor_t::take_interrupt()
180 reg_t pending_interrupts
= state
.mip
& state
.mie
;
182 reg_t mie
= get_field(state
.mstatus
, MSTATUS_MIE
);
183 reg_t m_enabled
= state
.prv
< PRV_M
|| (state
.prv
== PRV_M
&& mie
);
184 reg_t enabled_interrupts
= pending_interrupts
& ~state
.mideleg
& -m_enabled
;
186 reg_t sie
= get_field(state
.mstatus
, MSTATUS_SIE
);
187 reg_t s_enabled
= state
.prv
< PRV_S
|| (state
.prv
== PRV_S
&& sie
);
188 enabled_interrupts
|= pending_interrupts
& state
.mideleg
& -s_enabled
;
190 if (enabled_interrupts
)
191 raise_interrupt(ctz(enabled_interrupts
));
194 static bool validate_priv(reg_t priv
)
196 return priv
== PRV_U
|| priv
== PRV_S
|| priv
== PRV_M
;
199 void processor_t::set_privilege(reg_t prv
)
201 assert(validate_priv(prv
));
206 void processor_t::take_trap(trap_t
& t
, reg_t epc
)
209 fprintf(stderr
, "core %3d: exception %s, epc 0x%016" PRIx64
"\n",
212 if (t
.cause() == CAUSE_BREAKPOINT
) {
213 // TODO: Only do this if there is a debugger attached.
214 set_halted(true, HR_SWBP
);
218 // by default, trap to M-mode, unless delegated to S-mode
219 reg_t bit
= t
.cause();
220 reg_t deleg
= state
.medeleg
;
221 if (bit
& ((reg_t
)1 << (max_xlen
-1)))
222 deleg
= state
.mideleg
, bit
&= ~((reg_t
)1 << (max_xlen
-1));
223 if (state
.prv
<= PRV_S
&& bit
< max_xlen
&& ((deleg
>> bit
) & 1)) {
224 // handle the trap in S-mode
225 state
.pc
= state
.stvec
;
226 state
.scause
= t
.cause();
229 state
.sbadaddr
= t
.get_badaddr();
231 reg_t s
= state
.mstatus
;
232 s
= set_field(s
, MSTATUS_SPIE
, get_field(s
, MSTATUS_UIE
<< state
.prv
));
233 s
= set_field(s
, MSTATUS_SPP
, state
.prv
);
234 s
= set_field(s
, MSTATUS_SIE
, 0);
235 set_csr(CSR_MSTATUS
, s
);
236 set_privilege(PRV_S
);
238 state
.pc
= state
.mtvec
;
239 state
.mcause
= t
.cause();
242 state
.mbadaddr
= t
.get_badaddr();
244 reg_t s
= state
.mstatus
;
245 s
= set_field(s
, MSTATUS_MPIE
, get_field(s
, MSTATUS_UIE
<< state
.prv
));
246 s
= set_field(s
, MSTATUS_MPP
, state
.prv
);
247 s
= set_field(s
, MSTATUS_MIE
, 0);
248 set_csr(CSR_MSTATUS
, s
);
249 set_privilege(PRV_M
);
252 yield_load_reservation();
255 void processor_t::disasm(insn_t insn
)
257 uint64_t bits
= insn
.bits() & ((1ULL << (8 * insn_length(insn
.bits()))) - 1);
258 fprintf(stderr
, "core %3d: 0x%016" PRIx64
" (0x%08" PRIx64
") %s\n",
259 id
, state
.pc
, bits
, disassembler
->disassemble(insn
).c_str());
262 static bool validate_vm(int max_xlen
, reg_t vm
)
264 if (max_xlen
== 64 && (vm
== VM_SV39
|| vm
== VM_SV48
))
266 if (max_xlen
== 32 && vm
== VM_SV32
)
268 return vm
== VM_MBARE
;
271 void processor_t::set_csr(int which
, reg_t val
)
273 val
= zext_xlen(val
);
274 reg_t delegable_ints
= MIP_SSIP
| MIP_STIP
| MIP_SEIP
| (1 << IRQ_COP
);
275 reg_t all_ints
= delegable_ints
| MIP_MSIP
| MIP_MTIP
;
280 state
.fflags
= val
& (FSR_AEXC
>> FSR_AEXC_SHIFT
);
284 state
.frm
= val
& (FSR_RD
>> FSR_RD_SHIFT
);
288 state
.fflags
= (val
& FSR_AEXC
) >> FSR_AEXC_SHIFT
;
289 state
.frm
= (val
& FSR_RD
) >> FSR_RD_SHIFT
;
292 if ((val
^ state
.mstatus
) &
293 (MSTATUS_VM
| MSTATUS_MPP
| MSTATUS_MPRV
| MSTATUS_PUM
))
296 reg_t mask
= MSTATUS_SIE
| MSTATUS_SPIE
| MSTATUS_MIE
| MSTATUS_MPIE
297 | MSTATUS_SPP
| MSTATUS_FS
| MSTATUS_MPRV
| MSTATUS_PUM
298 | (ext
? MSTATUS_XS
: 0);
300 if (validate_vm(max_xlen
, get_field(val
, MSTATUS_VM
)))
302 if (validate_priv(get_field(val
, MSTATUS_MPP
)))
305 state
.mstatus
= (state
.mstatus
& ~mask
) | (val
& mask
);
307 bool dirty
= (state
.mstatus
& MSTATUS_FS
) == MSTATUS_FS
;
308 dirty
|= (state
.mstatus
& MSTATUS_XS
) == MSTATUS_XS
;
310 state
.mstatus
= set_field(state
.mstatus
, MSTATUS32_SD
, dirty
);
312 state
.mstatus
= set_field(state
.mstatus
, MSTATUS64_SD
, dirty
);
314 // spike supports the notion of xlen < max_xlen, but current priv spec
315 // doesn't provide a mechanism to run RV32 software on an RV64 machine
320 reg_t mask
= MIP_SSIP
| MIP_STIP
;
321 state
.mip
= (state
.mip
& ~mask
) | (val
& mask
);
325 state
.mie
= (state
.mie
& ~all_ints
) | (val
& all_ints
);
328 state
.mideleg
= (state
.mideleg
& ~delegable_ints
) | (val
& delegable_ints
);
332 #define DECLARE_CAUSE(name, value) mask |= 1ULL << (value);
333 #include "encoding.h"
335 state
.medeleg
= (state
.medeleg
& ~mask
) | (val
& mask
);
338 case CSR_MUCOUNTEREN
:
339 state
.mucounteren
= val
& 7;
341 case CSR_MSCOUNTEREN
:
342 state
.mscounteren
= val
& 7;
345 reg_t mask
= SSTATUS_SIE
| SSTATUS_SPIE
| SSTATUS_SPP
| SSTATUS_FS
346 | SSTATUS_XS
| SSTATUS_PUM
;
347 return set_csr(CSR_MSTATUS
, (state
.mstatus
& ~mask
) | (val
& mask
));
350 return set_csr(CSR_MIP
,
351 (state
.mip
& ~state
.mideleg
) | (val
& state
.mideleg
));
353 return set_csr(CSR_MIE
,
354 (state
.mie
& ~state
.mideleg
) | (val
& state
.mideleg
));
355 case CSR_SEPC
: state
.sepc
= val
; break;
356 case CSR_STVEC
: state
.stvec
= val
>> 2 << 2; break;
357 case CSR_SPTBR
: state
.sptbr
= val
; break;
358 case CSR_SSCRATCH
: state
.sscratch
= val
; break;
359 case CSR_SCAUSE
: state
.scause
= val
; break;
360 case CSR_SBADADDR
: state
.sbadaddr
= val
; break;
361 case CSR_MEPC
: state
.mepc
= val
; break;
362 case CSR_MTVEC
: state
.mtvec
= val
>> 2 << 2; break;
363 case CSR_MSCRATCH
: state
.mscratch
= val
; break;
364 case CSR_MCAUSE
: state
.mcause
= val
; break;
365 case CSR_MBADADDR
: state
.mbadaddr
= val
; break;
369 reg_t
processor_t::get_csr(int which
)
375 if (!supports_extension('F'))
380 if (!supports_extension('F'))
385 if (!supports_extension('F'))
387 return (state
.fflags
<< FSR_AEXC_SHIFT
) | (state
.frm
<< FSR_RD_SHIFT
);
391 if ((state
.mucounteren
>> (which
& (xlen
-1))) & 1)
392 return get_csr(which
+ (CSR_MCYCLE
- CSR_CYCLE
));
397 if ((state
.mscounteren
>> (which
& (xlen
-1))) & 1)
398 return get_csr(which
+ (CSR_MCYCLE
- CSR_SCYCLE
));
400 case CSR_MUCOUNTEREN
: return state
.mucounteren
;
401 case CSR_MSCOUNTEREN
: return state
.mscounteren
;
402 case CSR_MUCYCLE_DELTA
: return 0;
403 case CSR_MUTIME_DELTA
: return 0;
404 case CSR_MUINSTRET_DELTA
: return 0;
405 case CSR_MSCYCLE_DELTA
: return 0;
406 case CSR_MSTIME_DELTA
: return 0;
407 case CSR_MSINSTRET_DELTA
: return 0;
408 case CSR_MUCYCLE_DELTAH
: if (xlen
> 32) break; else return 0;
409 case CSR_MUTIME_DELTAH
: if (xlen
> 32) break; else return 0;
410 case CSR_MUINSTRET_DELTAH
: if (xlen
> 32) break; else return 0;
411 case CSR_MSCYCLE_DELTAH
: if (xlen
> 32) break; else return 0;
412 case CSR_MSTIME_DELTAH
: if (xlen
> 32) break; else return 0;
413 case CSR_MSINSTRET_DELTAH
: if (xlen
> 32) break; else return 0;
414 case CSR_MCYCLE
: return state
.minstret
;
415 case CSR_MINSTRET
: return state
.minstret
;
416 case CSR_MCYCLEH
: if (xlen
> 32) break; else return state
.minstret
>> 32;
417 case CSR_MINSTRETH
: if (xlen
> 32) break; else return state
.minstret
>> 32;
419 reg_t mask
= SSTATUS_SIE
| SSTATUS_SPIE
| SSTATUS_SPP
| SSTATUS_FS
420 | SSTATUS_XS
| SSTATUS_PUM
;
421 reg_t sstatus
= state
.mstatus
& mask
;
422 if ((sstatus
& SSTATUS_FS
) == SSTATUS_FS
||
423 (sstatus
& SSTATUS_XS
) == SSTATUS_XS
)
424 sstatus
|= (xlen
== 32 ? SSTATUS32_SD
: SSTATUS64_SD
);
427 case CSR_SIP
: return state
.mip
& state
.mideleg
;
428 case CSR_SIE
: return state
.mie
& state
.mideleg
;
429 case CSR_SEPC
: return state
.sepc
;
430 case CSR_SBADADDR
: return state
.sbadaddr
;
431 case CSR_STVEC
: return state
.stvec
;
434 return state
.scause
| ((state
.scause
>> (max_xlen
-1)) << (xlen
-1));
436 case CSR_SPTBR
: return state
.sptbr
;
437 case CSR_SASID
: return 0;
438 case CSR_SSCRATCH
: return state
.sscratch
;
439 case CSR_MSTATUS
: return state
.mstatus
;
440 case CSR_MIP
: return state
.mip
;
441 case CSR_MIE
: return state
.mie
;
442 case CSR_MEPC
: return state
.mepc
;
443 case CSR_MSCRATCH
: return state
.mscratch
;
444 case CSR_MCAUSE
: return state
.mcause
;
445 case CSR_MBADADDR
: return state
.mbadaddr
;
446 case CSR_MISA
: return isa
;
447 case CSR_MARCHID
: return 0;
448 case CSR_MIMPID
: return 0;
449 case CSR_MVENDORID
: return 0;
450 case CSR_MHARTID
: return id
;
451 case CSR_MTVEC
: return state
.mtvec
;
452 case CSR_MEDELEG
: return state
.medeleg
;
453 case CSR_MIDELEG
: return state
.mideleg
;
455 throw trap_illegal_instruction();
458 reg_t
illegal_instruction(processor_t
* p
, insn_t insn
, reg_t pc
)
460 throw trap_illegal_instruction();
463 insn_func_t
processor_t::decode_insn(insn_t insn
)
465 // look up opcode in hash table
466 size_t idx
= insn
.bits() % OPCODE_CACHE_SIZE
;
467 insn_desc_t desc
= opcode_cache
[idx
];
469 if (unlikely(insn
.bits() != desc
.match
)) {
470 // fall back to linear search
471 insn_desc_t
* p
= &instructions
[0];
472 while ((insn
.bits() & p
->mask
) != p
->match
)
476 if (p
->mask
!= 0 && p
> &instructions
[0]) {
477 if (p
->match
!= (p
-1)->match
&& p
->match
!= (p
+1)->match
) {
478 // move to front of opcode list to reduce miss penalty
479 while (--p
>= &instructions
[0])
481 instructions
[0] = desc
;
485 opcode_cache
[idx
] = desc
;
486 opcode_cache
[idx
].match
= insn
.bits();
489 return xlen
== 64 ? desc
.rv64
: desc
.rv32
;
492 void processor_t::register_insn(insn_desc_t desc
)
494 instructions
.push_back(desc
);
497 void processor_t::build_opcode_map()
500 bool operator()(const insn_desc_t
& lhs
, const insn_desc_t
& rhs
) {
501 if (lhs
.match
== rhs
.match
)
502 return lhs
.mask
> rhs
.mask
;
503 return lhs
.match
> rhs
.match
;
506 std::sort(instructions
.begin(), instructions
.end(), cmp());
508 for (size_t i
= 0; i
< OPCODE_CACHE_SIZE
; i
++)
509 opcode_cache
[i
] = {1, 0, &illegal_instruction
, &illegal_instruction
};
512 void processor_t::register_extension(extension_t
* x
)
514 for (auto insn
: x
->get_instructions())
517 for (auto disasm_insn
: x
->get_disasms())
518 disassembler
->add_insn(disasm_insn
);
520 throw std::logic_error("only one extension may be registered");
522 x
->set_processor(this);
525 void processor_t::register_base_instructions()
527 #define DECLARE_INSN(name, match, mask) \
528 insn_bits_t name##_match = (match), name##_mask = (mask);
529 #include "encoding.h"
532 #define DEFINE_INSN(name) \
533 REGISTER_INSN(this, name, name##_match, name##_mask)
534 #include "insn_list.h"
537 register_insn({0, 0, &illegal_instruction
, &illegal_instruction
});
541 bool processor_t::load(reg_t addr
, size_t len
, uint8_t* bytes
)
546 bool processor_t::store(reg_t addr
, size_t len
, const uint8_t* bytes
)
551 state
.mip
&= ~MIP_MSIP
;
553 state
.mip
|= MIP_MSIP
;