+// See LICENSE for license details.
#ifndef _RISCV_PROCESSOR_H
#define _RISCV_PROCESSOR_H
#include "decode.h"
-#include <cstring>
-#include "trap.h"
-#include "mmu.h"
-#include "icsim.h"
-
-#define MAX_UTS 32
+#include "config.h"
+#include "devices.h"
+#include <string>
+#include <vector>
+#include <map>
+class processor_t;
+class mmu_t;
+typedef reg_t (*insn_func_t)(processor_t*, insn_t, reg_t);
class sim_t;
+class trap_t;
+class extension_t;
+class disassembler_t;
+
+struct insn_desc_t
+{
+ insn_bits_t match;
+ insn_bits_t mask;
+ insn_func_t rv32;
+ insn_func_t rv64;
+};
+
+struct commit_log_reg_t
+{
+ reg_t addr;
+ reg_t data;
+};
+
+typedef struct
+{
+ uint8_t prv;
+ bool step;
+ bool ebreakm;
+ bool ebreakh;
+ bool ebreaks;
+ bool ebreaku;
+ bool halt;
+ uint8_t cause;
+} dcsr_t;
+
+typedef enum
+{
+ ACTION_DEBUG_EXCEPTION = MCONTROL_ACTION_DEBUG_EXCEPTION,
+ ACTION_DEBUG_MODE = MCONTROL_ACTION_DEBUG_MODE,
+ ACTION_TRACE_START = MCONTROL_ACTION_TRACE_START,
+ ACTION_TRACE_STOP = MCONTROL_ACTION_TRACE_STOP,
+ ACTION_TRACE_EMIT = MCONTROL_ACTION_TRACE_EMIT
+} mcontrol_action_t;
+
+typedef enum
+{
+ MATCH_EQUAL = MCONTROL_MATCH_EQUAL,
+ MATCH_NAPOT = MCONTROL_MATCH_NAPOT,
+ MATCH_GE = MCONTROL_MATCH_GE,
+ MATCH_LT = MCONTROL_MATCH_LT,
+ MATCH_MASK_LOW = MCONTROL_MATCH_MASK_LOW,
+ MATCH_MASK_HIGH = MCONTROL_MATCH_MASK_HIGH
+} mcontrol_match_t;
-class processor_t
+typedef struct
+{
+ uint8_t type;
+ bool dmode;
+ uint8_t maskmax;
+ bool select;
+ bool timing;
+ mcontrol_action_t action;
+ bool chain;
+ mcontrol_match_t match;
+ bool m;
+ bool h;
+ bool s;
+ bool u;
+ bool execute;
+ bool store;
+ bool load;
+} mcontrol_t;
+
+// architectural state of a RISC-V hart
+struct state_t
+{
+ void reset();
+
+ static const int num_triggers = 4;
+
+ reg_t pc;
+ regfile_t<reg_t, NXPR, true> XPR;
+ regfile_t<freg_t, NFPR, false> FPR;
+
+ // control and status registers
+ reg_t prv; // TODO: Can this be an enum instead?
+ reg_t mstatus;
+ reg_t mepc;
+ reg_t mbadaddr;
+ reg_t mscratch;
+ reg_t mtvec;
+ reg_t mcause;
+ reg_t minstret;
+ reg_t mie;
+ reg_t mip;
+ reg_t medeleg;
+ reg_t mideleg;
+ uint32_t mcounteren;
+ uint32_t scounteren;
+ reg_t sepc;
+ reg_t sbadaddr;
+ reg_t sscratch;
+ reg_t stvec;
+ reg_t sptbr;
+ reg_t scause;
+ reg_t dpc;
+ reg_t dscratch;
+ dcsr_t dcsr;
+ reg_t tselect;
+ mcontrol_t mcontrol[num_triggers];
+ reg_t tdata2[num_triggers];
+
+ uint32_t fflags;
+ uint32_t frm;
+ bool serialized; // whether timer CSRs are in a well-defined state
+
+ // When true, execute a single instruction and then enter debug mode. This
+ // can only be set by executing dret.
+ enum {
+ STEP_NONE,
+ STEP_STEPPING,
+ STEP_STEPPED
+ } single_step;
+
+ reg_t load_reservation;
+
+#ifdef RISCV_ENABLE_COMMITLOG
+ commit_log_reg_t log_reg_write;
+ reg_t last_inst_priv;
+#endif
+};
+
+typedef enum {
+ OPERATION_EXECUTE,
+ OPERATION_STORE,
+ OPERATION_LOAD,
+} trigger_operation_t;
+
+// Count number of contiguous 1 bits starting from the LSB.
+static int cto(reg_t val)
+{
+ int res = 0;
+ while ((val & 1) == 1)
+ val >>= 1, res++;
+ return res;
+}
+
+// this class represents one processor in a RISC-V machine.
+class processor_t : public abstract_device_t
{
public:
- processor_t(sim_t* _sim, char* _mem, size_t _memsz);
+ processor_t(const char* isa, sim_t* sim, uint32_t id, bool halt_on_reset=false);
~processor_t();
- void init(uint32_t _id, icsim_t* defualt_icache, icsim_t* default_dcache);
- void step(size_t n, bool noisy);
+
+ void set_debug(bool value);
+ void set_histogram(bool value);
+ void reset();
+ void step(size_t n); // run for n cycles
+ void set_csr(int which, reg_t val);
+ reg_t get_csr(int which);
+ mmu_t* get_mmu() { return mmu; }
+ state_t* get_state() { return &state; }
+ extension_t* get_extension() { return ext; }
+ bool supports_extension(unsigned char ext) {
+ if (ext >= 'a' && ext <= 'z') ext += 'A' - 'a';
+ return ext >= 'A' && ext <= 'Z' && ((isa >> (ext - 'A')) & 1);
+ }
+ void set_privilege(reg_t);
+ void yield_load_reservation() { state.load_reservation = (reg_t)-1; }
+ void update_histogram(reg_t pc);
+ const disassembler_t* get_disassembler() { return disassembler; }
+
+ void register_insn(insn_desc_t);
+ void register_extension(extension_t*);
+
+ // MMIO slave interface
+ bool load(reg_t addr, size_t len, uint8_t* bytes);
+ bool store(reg_t addr, size_t len, const uint8_t* bytes);
+
+ // When true, display disassembly of each instruction that's executed.
+ bool debug;
+ // When true, take the slow simulation path.
+ bool slow_path();
+
+ // Return the index of a trigger that matched, or -1.
+ inline int trigger_match(trigger_operation_t operation, reg_t address, reg_t data)
+ {
+ if (state.dcsr.cause)
+ return -1;
+
+ bool chain_ok = true;
+
+ for (unsigned int i = 0; i < state.num_triggers; i++) {
+ if (!chain_ok) {
+ chain_ok |= !state.mcontrol[i].chain;
+ continue;
+ }
+
+ if ((operation == OPERATION_EXECUTE && !state.mcontrol[i].execute) ||
+ (operation == OPERATION_STORE && !state.mcontrol[i].store) ||
+ (operation == OPERATION_LOAD && !state.mcontrol[i].load) ||
+ (state.prv == PRV_M && !state.mcontrol[i].m) ||
+ (state.prv == PRV_H && !state.mcontrol[i].h) ||
+ (state.prv == PRV_S && !state.mcontrol[i].s) ||
+ (state.prv == PRV_U && !state.mcontrol[i].u)) {
+ continue;
+ }
+
+ reg_t value;
+ if (state.mcontrol[i].select) {
+ value = data;
+ } else {
+ value = address;
+ }
+
+ // We need this because in 32-bit mode sometimes the PC bits get sign
+ // extended.
+ if (xlen == 32) {
+ value &= 0xffffffff;
+ }
+
+ switch (state.mcontrol[i].match) {
+ case MATCH_EQUAL:
+ if (value != state.tdata2[i])
+ continue;
+ break;
+ case MATCH_NAPOT:
+ {
+ reg_t mask = ~((1 << cto(state.tdata2[i])) - 1);
+ if ((value & mask) != (state.tdata2[i] & mask))
+ continue;
+ }
+ break;
+ case MATCH_GE:
+ if (value < state.tdata2[i])
+ continue;
+ break;
+ case MATCH_LT:
+ if (value >= state.tdata2[i])
+ continue;
+ break;
+ case MATCH_MASK_LOW:
+ {
+ reg_t mask = state.tdata2[i] >> (xlen/2);
+ if ((value & mask) != (state.tdata2[i] & mask))
+ continue;
+ }
+ break;
+ case MATCH_MASK_HIGH:
+ {
+ reg_t mask = state.tdata2[i] >> (xlen/2);
+ if (((value >> (xlen/2)) & mask) != (state.tdata2[i] & mask))
+ continue;
+ }
+ break;
+ }
+
+ if (!state.mcontrol[i].chain) {
+ return i;
+ }
+ chain_ok = true;
+ }
+ return -1;
+ }
+
+ void trigger_updated();
private:
sim_t* sim;
+ mmu_t* mmu; // main memory is always accessed via the mmu
+ extension_t* ext;
+ disassembler_t* disassembler;
+ state_t state;
+ uint32_t id;
+ unsigned max_xlen;
+ unsigned xlen;
+ reg_t isa;
+ reg_t max_isa;
+ std::string isa_string;
+ bool histogram_enabled;
+ bool halt_on_reset;
- // architected state
- reg_t XPR[NXPR];
- freg_t FPR[NFPR];
+ std::vector<insn_desc_t> instructions;
+ std::map<reg_t,uint64_t> pc_histogram;
- // privileged control registers
- reg_t pc;
- reg_t epc;
- reg_t badvaddr;
- reg_t cause;
- reg_t evec;
- reg_t tohost;
- reg_t fromhost;
- reg_t vecbanks;
- reg_t pcr_k0;
- reg_t pcr_k1;
- uint32_t id;
- uint32_t sr;
- uint32_t count;
- uint32_t compare;
- uint32_t vecbanks_count;
-
- // unprivileged control registers
- uint32_t fsr;
-
- // # of bits in an XPR (32 or 64). (redundant with sr)
- int xprlen;
-
- // shared memory
- mmu_t mmu;
-
- // counters
- reg_t counters[32];
-
- // functions
- void set_sr(uint32_t val);
- void set_fsr(uint32_t val);
- void take_trap(trap_t t, bool noisy);
- void disasm(insn_t insn, reg_t pc);
-
- // vector stuff
- void vcfg();
- void setvl(int vlapp);
-
- bool utmode;
- int utidx;
- int vlmax;
- int vl;
- int nxpr_all;
- int nfpr_all;
- int nxpr_use;
- int nfpr_use;
- processor_t* uts[MAX_UTS];
-
- // cache sim
- icsim_t* icsim;
- icsim_t* dcsim;
- icsim_t* itlbsim;
- icsim_t* dtlbsim;
+ static const size_t OPCODE_CACHE_SIZE = 8191;
+ insn_desc_t opcode_cache[OPCODE_CACHE_SIZE];
+
+ void take_pending_interrupt() { take_interrupt(state.mip & state.mie); }
+ void take_interrupt(reg_t mask); // take first enabled interrupt in mask
+ void take_trap(trap_t& t, reg_t epc); // take an exception
+ void disasm(insn_t insn); // disassemble and print an instruction
+ int paddr_bits();
+
+ void enter_debug_mode(uint8_t cause);
friend class sim_t;
+ friend class mmu_t;
+ friend class rtc_t;
+ friend class extension_t;
+
+ void parse_isa_string(const char* isa);
+ void build_opcode_map();
+ void register_base_instructions();
+ insn_func_t decode_insn(insn_t insn);
};
+reg_t illegal_instruction(processor_t* p, insn_t insn, reg_t pc);
+
+#define REGISTER_INSN(proc, name, match, mask) \
+ extern reg_t rv32_##name(processor_t*, insn_t, reg_t); \
+ extern reg_t rv64_##name(processor_t*, insn_t, reg_t); \
+ proc->register_insn((insn_desc_t){match, mask, rv32_##name, rv64_##name});
+
#endif