1 // See LICENSE for license details.
22 processor_t::processor_t(const char* isa
, sim_t
* sim
, uint32_t id
)
23 : sim(sim
), ext(NULL
), disassembler(new disassembler_t
),
24 id(id
), run(false), debug(false)
26 parse_isa_string(isa
);
28 mmu
= new mmu_t(sim
->mem
, sim
->memsz
);
29 mmu
->set_processor(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";
67 cpuid
= reg_t(2) << 62;
69 if (strncmp(p
, "rv32", 4) == 0)
70 max_xlen
= 32, cpuid
= 0, 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
= "rv" + std::to_string(max_xlen
) + p
;
86 cpuid
|= 1L << ('s' - 'a'); // advertise support for supervisor mode
89 cpuid
|= 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'))
109 void state_t::reset()
111 memset(this, 0, sizeof(*this));
113 pc
= DEFAULT_MTVEC
+ 0x100;
114 load_reservation
= -1;
117 void processor_t::set_debug(bool value
)
121 ext
->set_debug(value
);
124 void processor_t::set_histogram(bool value
)
126 histogram_enabled
= value
;
127 #ifndef RISCV_ENABLE_HISTOGRAM
129 fprintf(stderr
, "PC Histogram support has not been properly enabled;");
130 fprintf(stderr
, " please re-build the riscv-isa-run project using \"configure --enable-histogram\".\n");
135 void processor_t::reset(bool value
)
142 set_csr(CSR_MSTATUS
, state
.mstatus
);
145 ext
->reset(); // reset the extension
148 void processor_t::raise_interrupt(reg_t which
)
150 throw trap_t(((reg_t
)1 << (max_xlen
-1)) | which
);
153 static int ctz(reg_t val
)
157 while ((val
& 1) == 0)
162 void processor_t::take_interrupt()
166 reg_t interrupts
= state
.mip
& state
.mie
;
168 reg_t m_interrupts
= interrupts
& ~state
.mideleg
;
169 reg_t mie
= get_field(state
.mstatus
, MSTATUS_MIE
);
170 if ((state
.prv
< PRV_M
|| (state
.prv
== PRV_M
&& mie
)) && m_interrupts
)
171 raise_interrupt(ctz(m_interrupts
));
173 reg_t s_interrupts
= interrupts
& state
.mideleg
;
174 reg_t sie
= get_field(state
.mstatus
, MSTATUS_SIE
);
175 if ((state
.prv
< PRV_S
|| (state
.prv
== PRV_S
&& sie
)) && s_interrupts
)
176 raise_interrupt(ctz(s_interrupts
));
179 void processor_t::check_timer()
181 if (sim
->rtc
>= state
.mtimecmp
)
182 state
.mip
|= MIP_MTIP
;
185 static bool validate_priv(reg_t priv
)
187 return priv
== PRV_U
|| priv
== PRV_S
|| priv
== PRV_M
;
190 void processor_t::set_privilege(reg_t prv
)
192 assert(validate_priv(prv
));
197 void processor_t::take_trap(trap_t
& t
, reg_t epc
)
200 fprintf(stderr
, "core %3d: exception %s, epc 0x%016" PRIx64
"\n",
203 // by default, trap to M-mode, unless delegated to S-mode
204 reg_t bit
= t
.cause();
205 reg_t deleg
= state
.medeleg
;
206 if (bit
& ((reg_t
)1 << (max_xlen
-1)))
207 deleg
= state
.mideleg
, bit
&= ~((reg_t
)1 << (max_xlen
-1));
208 if (state
.prv
<= PRV_S
&& bit
< max_xlen
&& ((deleg
>> bit
) & 1)) {
209 // handle the trap in S-mode
210 state
.pc
= state
.stvec
;
211 state
.scause
= t
.cause();
214 state
.sbadaddr
= t
.get_badaddr();
216 reg_t s
= state
.mstatus
;
217 s
= set_field(s
, MSTATUS_SPIE
, get_field(s
, MSTATUS_UIE
<< state
.prv
));
218 s
= set_field(s
, MSTATUS_SPP
, state
.prv
);
219 s
= set_field(s
, MSTATUS_SIE
, 0);
220 set_csr(CSR_MSTATUS
, s
);
221 set_privilege(PRV_S
);
223 state
.pc
= DEFAULT_MTVEC
+ 0x40 * state
.prv
;
224 state
.mcause
= t
.cause();
227 state
.mbadaddr
= t
.get_badaddr();
229 reg_t s
= state
.mstatus
;
230 s
= set_field(s
, MSTATUS_MPIE
, get_field(s
, MSTATUS_UIE
<< state
.prv
));
231 s
= set_field(s
, MSTATUS_MPP
, state
.prv
);
232 s
= set_field(s
, MSTATUS_MIE
, 0);
233 set_csr(CSR_MSTATUS
, s
);
234 set_privilege(PRV_M
);
237 yield_load_reservation();
240 void processor_t::disasm(insn_t insn
)
242 uint64_t bits
= insn
.bits() & ((1ULL << (8 * insn_length(insn
.bits()))) - 1);
243 fprintf(stderr
, "core %3d: 0x%016" PRIx64
" (0x%08" PRIx64
") %s\n",
244 id
, state
.pc
, bits
, disassembler
->disassemble(insn
).c_str());
247 static bool validate_vm(int max_xlen
, reg_t vm
)
249 if (max_xlen
== 64 && (vm
== VM_SV39
|| vm
== VM_SV48
))
251 if (max_xlen
== 32 && vm
== VM_SV32
)
253 return vm
== VM_MBARE
;
256 void processor_t::set_csr(int which
, reg_t val
)
258 reg_t all_ints
= MIP_SSIP
| MIP_MSIP
| MIP_STIP
| MIP_MTIP
| (1UL << IRQ_HOST
);
259 reg_t s_ints
= MIP_SSIP
| MIP_STIP
;
264 state
.fflags
= val
& (FSR_AEXC
>> FSR_AEXC_SHIFT
);
268 state
.frm
= val
& (FSR_RD
>> FSR_RD_SHIFT
);
272 state
.fflags
= (val
& FSR_AEXC
) >> FSR_AEXC_SHIFT
;
273 state
.frm
= (val
& FSR_RD
) >> FSR_RD_SHIFT
;
277 // this implementation ignores writes to MTIME
281 // this implementation ignores writes to MTIME
286 state
.sutime_delta
= (uint32_t)val
| (state
.sutime_delta
>> 32 << 32);
288 state
.sutime_delta
= val
;
291 val
= ((val
<< 32) - sim
->rtc
) >> 32;
292 state
.sutime_delta
= (val
<< 32) | (uint32_t)state
.sutime_delta
;
296 val
-= state
.minstret
;
298 state
.suinstret_delta
= (uint32_t)val
| (state
.suinstret_delta
>> 32 << 32);
300 state
.suinstret_delta
= val
;
304 val
= ((val
<< 32) - state
.minstret
) >> 32;
305 state
.suinstret_delta
= (val
<< 32) | (uint32_t)state
.suinstret_delta
;
308 if ((val
^ state
.mstatus
) & (MSTATUS_VM
| MSTATUS_MPP
| MSTATUS_MPRV
))
311 reg_t mask
= MSTATUS_SIE
| MSTATUS_SPIE
| MSTATUS_MIE
| MSTATUS_MPIE
312 | MSTATUS_SPP
| MSTATUS_MPRV
| MSTATUS_FS
313 | (ext
? MSTATUS_XS
: 0);
315 if (validate_vm(max_xlen
, get_field(val
, MSTATUS_VM
)))
317 if (validate_priv(get_field(val
, MSTATUS_MPP
)))
320 state
.mstatus
= (state
.mstatus
& ~mask
) | (val
& mask
);
322 bool dirty
= (state
.mstatus
& MSTATUS_FS
) == MSTATUS_FS
;
323 dirty
|= (state
.mstatus
& MSTATUS_XS
) == MSTATUS_XS
;
325 state
.mstatus
= set_field(state
.mstatus
, MSTATUS32_SD
, dirty
);
327 state
.mstatus
= set_field(state
.mstatus
, MSTATUS64_SD
, dirty
);
329 // spike supports the notion of xlen < max_xlen, but current priv spec
330 // doesn't provide a mechanism to run RV32 software on an RV64 machine
335 reg_t mask
= all_ints
&~ MIP_MTIP
;
336 state
.mip
= (state
.mip
& ~mask
) | (val
& mask
);
340 state
.mip
= set_field(state
.mip
, MIP_MSIP
, val
& 1);
343 state
.mie
= (state
.mie
& ~all_ints
) | (val
& all_ints
);
346 state
.mideleg
= (state
.mideleg
& ~s_ints
) | (val
& s_ints
);
350 #define DECLARE_CAUSE(name, value) mask |= 1ULL << (value);
351 #include "encoding.h"
353 state
.medeleg
= (state
.medeleg
& ~mask
) | (val
& mask
);
357 reg_t mask
= SSTATUS_SIE
| SSTATUS_SPIE
| SSTATUS_SPP
| SSTATUS_FS
359 set_csr(CSR_MSTATUS
, (state
.mstatus
& ~mask
) | (val
& mask
));
363 reg_t mask
= s_ints
&~ MIP_STIP
;
364 state
.mip
= (state
.mip
& ~mask
) | (val
& mask
);
369 state
.mie
= (state
.mie
& ~mask
) | (val
& mask
);
372 case CSR_SEPC
: state
.sepc
= val
; break;
373 case CSR_STVEC
: state
.stvec
= val
>> 2 << 2; break;
374 case CSR_SPTBR
: state
.sptbr
= zext_xlen(val
& -PGSIZE
); break;
375 case CSR_SSCRATCH
: state
.sscratch
= val
; break;
376 case CSR_SCAUSE
: state
.scause
= val
; break;
377 case CSR_SBADADDR
: state
.sbadaddr
= val
; break;
378 case CSR_MEPC
: state
.mepc
= val
; break;
379 case CSR_MSCRATCH
: state
.mscratch
= val
; break;
380 case CSR_MCAUSE
: state
.mcause
= val
; break;
381 case CSR_MBADADDR
: state
.mbadaddr
= val
; break;
383 state
.mip
&= ~MIP_MTIP
;
384 state
.mtimecmp
= val
;
387 if (state
.tohost
== 0)
391 state
.mip
= (state
.mip
& ~(1 << IRQ_HOST
)) | (val
? (1 << IRQ_HOST
) : 0);
392 state
.fromhost
= val
;
397 reg_t
processor_t::get_csr(int which
)
403 if (!supports_extension('F'))
408 if (!supports_extension('F'))
413 if (!supports_extension('F'))
415 return (state
.fflags
<< FSR_AEXC_SHIFT
) | (state
.frm
<< FSR_RD_SHIFT
);
423 return sim
->rtc
>> 32;
426 return sim
->rtc
+ state
.sutime_delta
;
431 return state
.minstret
+ state
.suinstret_delta
;
436 return (sim
->rtc
+ state
.sutime_delta
) >> 32;
443 return (state
.minstret
+ state
.suinstret_delta
) >> 32;
445 reg_t sstatus
= state
.mstatus
&
446 (SSTATUS_SIE
| SSTATUS_SPIE
| SSTATUS_SPP
| SSTATUS_FS
| SSTATUS_XS
);
447 if ((sstatus
& SSTATUS_FS
) == SSTATUS_FS
||
448 (sstatus
& SSTATUS_XS
) == SSTATUS_XS
)
449 sstatus
|= (xlen
== 32 ? SSTATUS32_SD
: SSTATUS64_SD
);
452 case CSR_SIP
: return state
.mip
& (MIP_SSIP
| MIP_STIP
);
453 case CSR_SIE
: return state
.mie
& (MIP_SSIP
| MIP_STIP
);
454 case CSR_SEPC
: return state
.sepc
;
455 case CSR_SBADADDR
: return state
.sbadaddr
;
456 case CSR_STVEC
: return state
.stvec
;
459 return state
.scause
| ((state
.scause
>> (max_xlen
-1)) << (xlen
-1));
461 case CSR_SPTBR
: return state
.sptbr
;
462 case CSR_SASID
: return 0;
463 case CSR_SSCRATCH
: return state
.sscratch
;
464 case CSR_MSTATUS
: return state
.mstatus
;
465 case CSR_MIP
: return state
.mip
;
466 case CSR_MIPI
: return 0;
467 case CSR_MIE
: return state
.mie
;
468 case CSR_MEPC
: return state
.mepc
;
469 case CSR_MSCRATCH
: return state
.mscratch
;
470 case CSR_MCAUSE
: return state
.mcause
;
471 case CSR_MBADADDR
: return state
.mbadaddr
;
472 case CSR_MTIMECMP
: return state
.mtimecmp
;
473 case CSR_MCPUID
: return cpuid
;
474 case CSR_MIMPID
: return IMPL_ROCKET
;
475 case CSR_MHARTID
: return id
;
476 case CSR_MTVEC
: return DEFAULT_MTVEC
;
477 case CSR_MEDELEG
: return state
.medeleg
;
478 case CSR_MIDELEG
: return state
.mideleg
;
480 sim
->get_htif()->tick(); // not necessary, but faster
483 sim
->get_htif()->tick(); // not necessary, but faster
484 return state
.fromhost
;
485 case CSR_MIOBASE
: return sim
->memsz
;
504 throw trap_illegal_instruction();
507 reg_t
illegal_instruction(processor_t
* p
, insn_t insn
, reg_t pc
)
509 throw trap_illegal_instruction();
512 insn_func_t
processor_t::decode_insn(insn_t insn
)
514 // look up opcode in hash table
515 size_t idx
= insn
.bits() % OPCODE_CACHE_SIZE
;
516 insn_desc_t desc
= opcode_cache
[idx
];
518 if (unlikely(insn
.bits() != desc
.match
)) {
519 // fall back to linear search
520 insn_desc_t
* p
= &instructions
[0];
521 while ((insn
.bits() & p
->mask
) != p
->match
)
525 if (p
->mask
!= 0 && p
> &instructions
[0]) {
526 if (p
->match
!= (p
-1)->match
&& p
->match
!= (p
+1)->match
) {
527 // move to front of opcode list to reduce miss penalty
528 while (--p
>= &instructions
[0])
530 instructions
[0] = desc
;
534 opcode_cache
[idx
] = desc
;
535 opcode_cache
[idx
].match
= insn
.bits();
538 return xlen
== 64 ? desc
.rv64
: desc
.rv32
;
541 void processor_t::register_insn(insn_desc_t desc
)
543 instructions
.push_back(desc
);
546 void processor_t::build_opcode_map()
549 bool operator()(const insn_desc_t
& lhs
, const insn_desc_t
& rhs
) {
550 if (lhs
.match
== rhs
.match
)
551 return lhs
.mask
> rhs
.mask
;
552 return lhs
.match
> rhs
.match
;
555 std::sort(instructions
.begin(), instructions
.end(), cmp());
557 for (size_t i
= 0; i
< OPCODE_CACHE_SIZE
; i
++)
558 opcode_cache
[i
] = {1, 0, &illegal_instruction
, &illegal_instruction
};
561 void processor_t::register_extension(extension_t
* x
)
563 for (auto insn
: x
->get_instructions())
566 for (auto disasm_insn
: x
->get_disasms())
567 disassembler
->add_insn(disasm_insn
);
569 throw std::logic_error("only one extension may be registered");
571 x
->set_processor(this);
574 void processor_t::register_base_instructions()
576 #define DECLARE_INSN(name, match, mask) \
577 insn_bits_t name##_match = (match), name##_mask = (mask);
578 #include "encoding.h"
581 #define DEFINE_INSN(name) \
582 REGISTER_INSN(this, name, name##_match, name##_mask)
583 #include "insn_list.h"
586 register_insn({0, 0, &illegal_instruction
, &illegal_instruction
});
590 bool processor_t::load(reg_t addr
, size_t len
, uint8_t* bytes
)
593 auto res
= get_csr(addr
/ (max_xlen
/ 8));
594 memcpy(bytes
, &res
, len
);
596 } catch (trap_illegal_instruction
& t
) {
601 bool processor_t::store(reg_t addr
, size_t len
, const uint8_t* bytes
)
605 memcpy(&value
, bytes
, len
);
606 set_csr(addr
/ (max_xlen
/ 8), value
);
608 } catch (trap_illegal_instruction
& t
) {