X-Git-Url: https://git.libre-soc.org/?a=blobdiff_plain;f=riscv%2Fprocessor.cc;h=7a5df901b315c7a5b1642c45415520cdcb659ef3;hb=0020b3b924417412200b4ce7eb423b4213443b02;hp=17d4069f2fc34fa66d707f4dc7a1fde1c8d8503a;hpb=a62a8196798141f3e76bc27da7671ab93951a677;p=riscv-isa-sim.git diff --git a/riscv/processor.cc b/riscv/processor.cc index 17d4069..7a5df90 100644 --- a/riscv/processor.cc +++ b/riscv/processor.cc @@ -19,9 +19,10 @@ #undef STATE #define STATE state -processor_t::processor_t(const char* isa, sim_t* sim, uint32_t id, +processor_t::processor_t(const char* isa, simif_t* sim, uint32_t id, bool halt_on_reset) - : debug(false), sim(sim), ext(NULL), id(id), halt_on_reset(halt_on_reset) + : debug(false), halt_request(false), sim(sim), ext(NULL), id(id), + halt_on_reset(halt_on_reset), last_pc(1), executions(1) { parse_isa_string(isa); register_base_instructions(); @@ -60,20 +61,20 @@ void processor_t::parse_isa_string(const char* str) lowercase += std::tolower(*r); const char* p = lowercase.c_str(); - const char* all_subsets = "imafdc"; + const char* all_subsets = "imafdqc"; max_xlen = 64; - isa = reg_t(2) << 62; + state.misa = reg_t(2) << 62; if (strncmp(p, "rv32", 4) == 0) - max_xlen = 32, isa = reg_t(1) << 30, p += 4; + max_xlen = 32, state.misa = reg_t(1) << 30, p += 4; else if (strncmp(p, "rv64", 4) == 0) p += 4; else if (strncmp(p, "rv", 2) == 0) p += 2; if (!*p) { - p = all_subsets; + p = "imafdc"; } else if (*p == 'g') { // treat "G" as "IMAFD" tmp = std::string("imafd") + (p+1); p = &tmp[0]; @@ -82,11 +83,11 @@ void processor_t::parse_isa_string(const char* str) } isa_string = "rv" + std::to_string(max_xlen) + p; - isa |= 1L << ('s' - 'a'); // advertise support for supervisor mode - isa |= 1L << ('u' - 'a'); // advertise support for user mode + state.misa |= 1L << ('s' - 'a'); // advertise support for supervisor mode + state.misa |= 1L << ('u' - 'a'); // advertise support for user mode while (*p) { - isa |= 1L << (*p - 'a'); + state.misa |= 1L << (*p - 'a'); if (auto next = strchr(all_subsets, *p)) { all_subsets = next + 1; @@ -105,19 +106,21 @@ void processor_t::parse_isa_string(const char* str) if (supports_extension('D') && !supports_extension('F')) bad_isa_string(str); - // advertise support for supervisor and user modes - isa |= 1L << ('s' - 'a'); - isa |= 1L << ('u' - 'a'); + if (supports_extension('Q') && !supports_extension('D')) + bad_isa_string(str); + + if (supports_extension('Q') && max_xlen < 64) + bad_isa_string(str); - max_isa = isa; + max_isa = state.misa; } -void state_t::reset() +void state_t::reset(reg_t max_isa) { memset(this, 0, sizeof(*this)); + misa = max_isa; prv = PRV_M; pc = DEFAULT_RSTVEC; - mtvec = DEFAULT_MTVEC; load_reservation = -1; tselect = 0; for (unsigned int i = 0; i < num_triggers; i++) @@ -144,18 +147,16 @@ void processor_t::set_histogram(bool value) void processor_t::reset() { - state.reset(); + state.reset(max_isa); state.dcsr.halt = halt_on_reset; halt_on_reset = false; set_csr(CSR_MSTATUS, state.mstatus); if (ext) ext->reset(); // reset the extension -} -void processor_t::raise_interrupt(reg_t which) -{ - throw trap_t(((reg_t)1 << (max_xlen-1)) | which); + if (sim) + sim->proc_reset(id); } // Count number of contiguous 0 bits starting from the LSB. @@ -168,29 +169,64 @@ static int ctz(reg_t val) return res; } -void processor_t::take_interrupt() +void processor_t::take_interrupt(reg_t pending_interrupts) { - reg_t pending_interrupts = state.mip & state.mie; - reg_t mie = get_field(state.mstatus, MSTATUS_MIE); reg_t m_enabled = state.prv < PRV_M || (state.prv == PRV_M && mie); reg_t enabled_interrupts = pending_interrupts & ~state.mideleg & -m_enabled; reg_t sie = get_field(state.mstatus, MSTATUS_SIE); reg_t s_enabled = state.prv < PRV_S || (state.prv == PRV_S && sie); - enabled_interrupts |= pending_interrupts & state.mideleg & -s_enabled; + // M-ints have highest priority; consider S-ints only if no M-ints pending + if (enabled_interrupts == 0) + enabled_interrupts = pending_interrupts & state.mideleg & -s_enabled; + + if (state.dcsr.cause == 0 && enabled_interrupts) { + // nonstandard interrupts have highest priority + if (enabled_interrupts >> IRQ_M_EXT) + enabled_interrupts = enabled_interrupts >> IRQ_M_EXT << IRQ_M_EXT; + // external interrupts have next-highest priority + else if (enabled_interrupts & (MIP_MEIP | MIP_SEIP)) + enabled_interrupts = enabled_interrupts & (MIP_MEIP | MIP_SEIP); + // software interrupts have next-highest priority + else if (enabled_interrupts & (MIP_MSIP | MIP_SSIP)) + enabled_interrupts = enabled_interrupts & (MIP_MSIP | MIP_SSIP); + // timer interrupts have next-highest priority + else if (enabled_interrupts & (MIP_MTIP | MIP_STIP)) + enabled_interrupts = enabled_interrupts & (MIP_MTIP | MIP_STIP); + else + abort(); + + throw trap_t(((reg_t)1 << (max_xlen-1)) | ctz(enabled_interrupts)); + } +} - if (enabled_interrupts) - raise_interrupt(ctz(enabled_interrupts)); +static int xlen_to_uxl(int xlen) +{ + if (xlen == 32) + return 1; + if (xlen == 64) + return 2; + abort(); } -void processor_t::set_privilege(reg_t prv) +reg_t processor_t::legalize_privilege(reg_t prv) { assert(prv <= PRV_M); - if (prv == PRV_H) - prv = PRV_U; + + if (!supports_extension('U')) + return PRV_M; + + if (prv == PRV_H || !supports_extension('S')) + return PRV_U; + + return prv; +} + +void processor_t::set_privilege(reg_t prv) +{ mmu->flush_tlb(); - state.prv = prv; + state.prv = legalize_privilege(prv); } void processor_t::enter_debug_mode(uint8_t cause) @@ -199,7 +235,7 @@ void processor_t::enter_debug_mode(uint8_t cause) state.dcsr.prv = state.prv; set_privilege(PRV_M); state.dpc = state.pc; - state.pc = DEBUG_ROM_START; + state.pc = DEBUG_ROM_ENTRY; } void processor_t::take_trap(trap_t& t, reg_t epc) @@ -207,53 +243,56 @@ void processor_t::take_trap(trap_t& t, reg_t epc) if (debug) { fprintf(stderr, "core %3d: exception %s, epc 0x%016" PRIx64 "\n", id, t.name(), epc); - if (t.has_badaddr()) - fprintf(stderr, "core %3d: badaddr 0x%016" PRIx64 "\n", id, - t.get_badaddr()); + if (t.has_tval()) + fprintf(stderr, "core %3d: tval 0x%016" PRIx64 "\n", id, + t.get_tval()); + } + + if (state.dcsr.cause) { + if (t.cause() == CAUSE_BREAKPOINT) { + state.pc = DEBUG_ROM_ENTRY; + } else { + state.pc = DEBUG_ROM_TVEC; + } + return; } if (t.cause() == CAUSE_BREAKPOINT && ( (state.prv == PRV_M && state.dcsr.ebreakm) || - (state.prv == PRV_H && state.dcsr.ebreakh) || (state.prv == PRV_S && state.dcsr.ebreaks) || (state.prv == PRV_U && state.dcsr.ebreaku))) { enter_debug_mode(DCSR_CAUSE_SWBP); return; } - if (state.dcsr.cause) { - state.pc = DEBUG_ROM_EXCEPTION; - return; - } - // by default, trap to M-mode, unless delegated to S-mode reg_t bit = t.cause(); reg_t deleg = state.medeleg; - if (bit & ((reg_t)1 << (max_xlen-1))) + bool interrupt = (bit & ((reg_t)1 << (max_xlen-1))) != 0; + if (interrupt) deleg = state.mideleg, bit &= ~((reg_t)1 << (max_xlen-1)); if (state.prv <= PRV_S && bit < max_xlen && ((deleg >> bit) & 1)) { // handle the trap in S-mode state.pc = state.stvec; state.scause = t.cause(); state.sepc = epc; - if (t.has_badaddr()) - state.sbadaddr = t.get_badaddr(); + state.stval = t.get_tval(); reg_t s = state.mstatus; - s = set_field(s, MSTATUS_SPIE, get_field(s, MSTATUS_UIE << state.prv)); + s = set_field(s, MSTATUS_SPIE, get_field(s, MSTATUS_SIE)); s = set_field(s, MSTATUS_SPP, state.prv); s = set_field(s, MSTATUS_SIE, 0); set_csr(CSR_MSTATUS, s); set_privilege(PRV_S); } else { - state.pc = state.mtvec; + reg_t vector = (state.mtvec & 1) && interrupt ? 4*bit : 0; + state.pc = (state.mtvec & ~(reg_t)1) + vector; state.mepc = epc; state.mcause = t.cause(); - if (t.has_badaddr()) - state.mbadaddr = t.get_badaddr(); + state.mtval = t.get_tval(); reg_t s = state.mstatus; - s = set_field(s, MSTATUS_MPIE, get_field(s, MSTATUS_UIE << state.prv)); + s = set_field(s, MSTATUS_MPIE, get_field(s, MSTATUS_MIE)); s = set_field(s, MSTATUS_MPP, state.prv); s = set_field(s, MSTATUS_MIE, 0); set_csr(CSR_MSTATUS, s); @@ -266,17 +305,19 @@ void processor_t::take_trap(trap_t& t, reg_t epc) void processor_t::disasm(insn_t insn) { uint64_t bits = insn.bits() & ((1ULL << (8 * insn_length(insn.bits()))) - 1); - fprintf(stderr, "core %3d: 0x%016" PRIx64 " (0x%08" PRIx64 ") %s\n", - id, state.pc, bits, disassembler->disassemble(insn).c_str()); -} + if (last_pc != state.pc || last_bits != bits) { + if (executions != 1) { + fprintf(stderr, "core %3d: Executed %" PRIx64 " times\n", id, executions); + } -static bool validate_vm(int max_xlen, reg_t vm) -{ - if (max_xlen == 64 && (vm == VM_SV39 || vm == VM_SV48)) - return true; - if (max_xlen == 32 && vm == VM_SV32) - return true; - return vm == VM_MBARE; + fprintf(stderr, "core %3d: 0x%016" PRIx64 " (0x%08" PRIx64 ") %s\n", + id, state.pc, bits, disassembler->disassemble(insn).c_str()); + last_pc = state.pc; + last_bits = bits; + executions = 1; + } else { + executions++; + } } int processor_t::paddr_bits() @@ -307,15 +348,19 @@ void processor_t::set_csr(int which, reg_t val) break; case CSR_MSTATUS: { if ((val ^ state.mstatus) & - (MSTATUS_VM | MSTATUS_MPP | MSTATUS_MPRV | MSTATUS_PUM | MSTATUS_MXR)) + (MSTATUS_MPP | MSTATUS_MPRV | MSTATUS_SUM | MSTATUS_MXR)) mmu->flush_tlb(); reg_t mask = MSTATUS_SIE | MSTATUS_SPIE | MSTATUS_MIE | MSTATUS_MPIE - | MSTATUS_SPP | MSTATUS_FS | MSTATUS_MPRV | MSTATUS_PUM - | MSTATUS_MPP | MSTATUS_MXR | (ext ? MSTATUS_XS : 0); + | MSTATUS_FS | MSTATUS_MPRV | MSTATUS_SUM + | MSTATUS_MXR | MSTATUS_TW | MSTATUS_TVM + | MSTATUS_TSR | MSTATUS_UXL | MSTATUS_SXL | + (ext ? MSTATUS_XS : 0); - if (validate_vm(max_xlen, get_field(val, MSTATUS_VM))) - mask |= MSTATUS_VM; + reg_t requested_mpp = legalize_privilege(get_field(val, MSTATUS_MPP)); + state.mstatus = set_field(state.mstatus, MSTATUS_MPP, requested_mpp); + if (supports_extension('S')) + mask |= MSTATUS_SPP; state.mstatus = (state.mstatus & ~mask) | (val & mask); @@ -326,8 +371,10 @@ void processor_t::set_csr(int which, reg_t val) else state.mstatus = set_field(state.mstatus, MSTATUS64_SD, dirty); - // spike supports the notion of xlen < max_xlen, but current priv spec - // doesn't provide a mechanism to run RV32 software on an RV64 machine + state.mstatus = set_field(state.mstatus, MSTATUS_UXL, xlen_to_uxl(max_xlen)); + state.mstatus = set_field(state.mstatus, MSTATUS_UXL, xlen_to_uxl(max_xlen)); + state.mstatus = set_field(state.mstatus, MSTATUS_SXL, xlen_to_uxl(max_xlen)); + // U-XLEN == S-XLEN == M-XLEN xlen = max_xlen; break; } @@ -343,10 +390,13 @@ void processor_t::set_csr(int which, reg_t val) state.mideleg = (state.mideleg & ~delegable_ints) | (val & delegable_ints); break; case CSR_MEDELEG: { - reg_t mask = 0; -#define DECLARE_CAUSE(name, value) mask |= 1ULL << (value); -#include "encoding.h" -#undef DECLARE_CAUSE + reg_t mask = + (1 << CAUSE_MISALIGNED_FETCH) | + (1 << CAUSE_BREAKPOINT) | + (1 << CAUSE_USER_ECALL) | + (1 << CAUSE_FETCH_PAGE_FAULT) | + (1 << CAUSE_LOAD_PAGE_FAULT) | + (1 << CAUSE_STORE_PAGE_FAULT); state.medeleg = (state.medeleg & ~mask) | (val & mask); break; } @@ -361,15 +411,15 @@ void processor_t::set_csr(int which, reg_t val) case CSR_MCYCLEH: state.minstret = (val << 32) | (state.minstret << 32 >> 32); break; - case CSR_MUCOUNTEREN: - state.mucounteren = val; + case CSR_SCOUNTEREN: + state.scounteren = val; break; - case CSR_MSCOUNTEREN: - state.mscounteren = val; + case CSR_MCOUNTEREN: + state.mcounteren = val; break; case CSR_SSTATUS: { reg_t mask = SSTATUS_SIE | SSTATUS_SPIE | SSTATUS_SPP | SSTATUS_FS - | SSTATUS_XS | SSTATUS_PUM; + | SSTATUS_XS | SSTATUS_SUM | SSTATUS_MXR; return set_csr(CSR_MSTATUS, (state.mstatus & ~mask) | (val & mask)); } case CSR_SIP: { @@ -379,21 +429,26 @@ void processor_t::set_csr(int which, reg_t val) case CSR_SIE: return set_csr(CSR_MIE, (state.mie & ~state.mideleg) | (val & state.mideleg)); - case CSR_SPTBR: { - // upper bits of sptbr are the ASID; we only support ASID = 0 - state.sptbr = val & (((reg_t)1 << (paddr_bits() - PGSHIFT)) - 1); + case CSR_SATP: { + mmu->flush_tlb(); + if (max_xlen == 32) + state.satp = val & (SATP32_PPN | SATP32_MODE); + if (max_xlen == 64 && (get_field(val, SATP64_MODE) == SATP_MODE_OFF || + get_field(val, SATP64_MODE) == SATP_MODE_SV39 || + get_field(val, SATP64_MODE) == SATP_MODE_SV48)) + state.satp = val & (SATP64_PPN | SATP64_MODE); break; } - case CSR_SEPC: state.sepc = val; break; + case CSR_SEPC: state.sepc = val & ~(reg_t)1; break; case CSR_STVEC: state.stvec = val >> 2 << 2; break; case CSR_SSCRATCH: state.sscratch = val; break; case CSR_SCAUSE: state.scause = val; break; - case CSR_SBADADDR: state.sbadaddr = val; break; - case CSR_MEPC: state.mepc = val; break; - case CSR_MTVEC: state.mtvec = val >> 2 << 2; break; + case CSR_STVAL: state.stval = val; break; + case CSR_MEPC: state.mepc = val & ~(reg_t)1; break; + case CSR_MTVEC: state.mtvec = val & ~(reg_t)2; break; case CSR_MSCRATCH: state.mscratch = val; break; case CSR_MCAUSE: state.mcause = val; break; - case CSR_MBADADDR: state.mbadaddr = val; break; + case CSR_MTVAL: state.mtval = val; break; case CSR_MISA: { if (!(val & (1L << ('F' - 'A')))) val &= ~(1L << ('D' - 'A')); @@ -407,7 +462,7 @@ void processor_t::set_csr(int which, reg_t val) mask |= 1L << ('C' - 'A'); mask &= max_isa; - isa = (val & mask) | (isa & ~mask); + state.misa = (val & mask) | (state.misa & ~mask); break; } case CSR_TSELECT: @@ -459,7 +514,7 @@ void processor_t::set_csr(int which, reg_t val) state.dcsr.halt = get_field(val, DCSR_HALT); break; case CSR_DPC: - state.dpc = val; + state.dpc = val & ~(reg_t)1; break; case CSR_DSCRATCH: state.dscratch = val; @@ -469,8 +524,11 @@ void processor_t::set_csr(int which, reg_t val) reg_t processor_t::get_csr(int which) { - reg_t ctr_en = state.prv == PRV_U ? state.mucounteren : - state.prv == PRV_S ? state.mscounteren : -1U; + uint32_t ctr_en = -1; + if (state.prv < PRV_M) + ctr_en &= state.mcounteren; + if (state.prv < PRV_S) + ctr_en &= state.scounteren; bool ctr_ok = (ctr_en >> (which & 31)) & 1; if (ctr_ok) { @@ -481,7 +539,7 @@ reg_t processor_t::get_csr(int which) } if (which >= CSR_MHPMCOUNTER3 && which <= CSR_MHPMCOUNTER31) return 0; - if (xlen == 32 && which >= CSR_MHPMCOUNTER3 && which <= CSR_MHPMCOUNTER31) + if (xlen == 32 && which >= CSR_MHPMCOUNTER3H && which <= CSR_MHPMCOUNTER31H) return 0; if (which >= CSR_MHPMEVENT3 && which <= CSR_MHPMEVENT31) return 0; @@ -511,16 +569,21 @@ reg_t processor_t::get_csr(int which) case CSR_MINSTRET: case CSR_MCYCLE: return state.minstret; + case CSR_INSTRETH: + case CSR_CYCLEH: + if (ctr_ok && xlen == 32) + return state.minstret >> 32; + break; case CSR_MINSTRETH: case CSR_MCYCLEH: if (xlen == 32) return state.minstret >> 32; break; - case CSR_MUCOUNTEREN: return state.mucounteren; - case CSR_MSCOUNTEREN: return state.mscounteren; + case CSR_SCOUNTEREN: return state.scounteren; + case CSR_MCOUNTEREN: return state.mcounteren; case CSR_SSTATUS: { reg_t mask = SSTATUS_SIE | SSTATUS_SPIE | SSTATUS_SPP | SSTATUS_FS - | SSTATUS_XS | SSTATUS_PUM; + | SSTATUS_XS | SSTATUS_SUM | SSTATUS_UXL; reg_t sstatus = state.mstatus & mask; if ((sstatus & SSTATUS_FS) == SSTATUS_FS || (sstatus & SSTATUS_XS) == SSTATUS_XS) @@ -530,13 +593,16 @@ reg_t processor_t::get_csr(int which) case CSR_SIP: return state.mip & state.mideleg; case CSR_SIE: return state.mie & state.mideleg; case CSR_SEPC: return state.sepc; - case CSR_SBADADDR: return state.sbadaddr; + case CSR_STVAL: return state.stval; case CSR_STVEC: return state.stvec; case CSR_SCAUSE: if (max_xlen > xlen) return state.scause | ((state.scause >> (max_xlen-1)) << (xlen-1)); return state.scause; - case CSR_SPTBR: return state.sptbr; + case CSR_SATP: + if (get_field(state.mstatus, MSTATUS_TVM)) + require_privilege(PRV_M); + return state.satp; case CSR_SSCRATCH: return state.sscratch; case CSR_MSTATUS: return state.mstatus; case CSR_MIP: return state.mip; @@ -544,8 +610,8 @@ reg_t processor_t::get_csr(int which) case CSR_MEPC: return state.mepc; case CSR_MSCRATCH: return state.mscratch; case CSR_MCAUSE: return state.mcause; - case CSR_MBADADDR: return state.mbadaddr; - case CSR_MISA: return isa; + case CSR_MTVAL: return state.mtval; + case CSR_MISA: return state.misa; case CSR_MARCHID: return 0; case CSR_MIMPID: return 0; case CSR_MVENDORID: return 0; @@ -590,19 +656,15 @@ reg_t processor_t::get_csr(int which) { uint32_t v = 0; v = set_field(v, DCSR_XDEBUGVER, 1); - v = set_field(v, DCSR_NDRESET, 0); - v = set_field(v, DCSR_FULLRESET, 0); - v = set_field(v, DCSR_PRV, state.dcsr.prv); - v = set_field(v, DCSR_STEP, state.dcsr.step); - v = set_field(v, DCSR_DEBUGINT, sim->debug_module.get_interrupt(id)); - v = set_field(v, DCSR_STOPCYCLE, 0); - v = set_field(v, DCSR_STOPTIME, 0); v = set_field(v, DCSR_EBREAKM, state.dcsr.ebreakm); v = set_field(v, DCSR_EBREAKH, state.dcsr.ebreakh); v = set_field(v, DCSR_EBREAKS, state.dcsr.ebreaks); v = set_field(v, DCSR_EBREAKU, state.dcsr.ebreaku); - v = set_field(v, DCSR_HALT, state.dcsr.halt); + v = set_field(v, DCSR_STOPCYCLE, 0); + v = set_field(v, DCSR_STOPTIME, 0); v = set_field(v, DCSR_CAUSE, state.dcsr.cause); + v = set_field(v, DCSR_STEP, state.dcsr.step); + v = set_field(v, DCSR_PRV, state.dcsr.prv); return v; } case CSR_DPC: @@ -610,12 +672,12 @@ reg_t processor_t::get_csr(int which) case CSR_DSCRATCH: return state.dscratch; } - throw trap_illegal_instruction(); + throw trap_illegal_instruction(0); } reg_t illegal_instruction(processor_t* p, insn_t insn, reg_t pc) { - throw trap_illegal_instruction(); + throw trap_illegal_instruction(0); } insn_func_t processor_t::decode_insn(insn_t insn) @@ -698,6 +760,17 @@ void processor_t::register_base_instructions() bool processor_t::load(reg_t addr, size_t len, uint8_t* bytes) { + switch (addr) + { + case 0: + if (len <= 4) { + memset(bytes, 0, len); + bytes[0] = get_field(state.mip, MIP_MSIP); + return true; + } + break; + } + return false; } @@ -706,14 +779,14 @@ bool processor_t::store(reg_t addr, size_t len, const uint8_t* bytes) switch (addr) { case 0: - state.mip &= ~MIP_MSIP; - if (bytes[0] & 1) - state.mip |= MIP_MSIP; - return true; - - default: - return false; + if (len <= 4) { + state.mip = set_field(state.mip, MIP_MSIP, bytes[0]); + return true; + } + break; } + + return false; } void processor_t::trigger_updated()