riscv/sim.cc

   1 #include "sim.h"
   2 #include "htif.h"
   3 #include <sys/mman.h>
   4 #include <map>
   5 #include <iostream>
   6 #include <climits>
   7 #include <assert.h>
   8
   9 #ifdef __linux__
  10 # define mmap mmap64
  11 #endif
  12
  13 sim_t::sim_t(int _nprocs, htif_t* _htif)
  14   : htif(_htif),
  15     procs(_nprocs),
  16     running(false),
  17     steps(0)
  18 {
  19   // allocate target machine's memory, shrinking it as necessary
  20   // until the allocation succeeds
  21
  22   size_t memsz0 = sizeof(size_t) == 8 ? 0x100000000ULL : 0x70000000UL;
  23   size_t quantum = std::max(PGSIZE, (reg_t)sysconf(_SC_PAGESIZE));
  24   memsz0 = memsz0/quantum*quantum;
  25
  26   memsz = memsz0;
  27   mem = (char*)mmap(NULL, memsz, PROT_WRITE, MAP_PRIVATE|MAP_ANON, -1, 0);
  28
  29   if(mem == MAP_FAILED)
  30   {
  31     while(mem == MAP_FAILED && (memsz = memsz*10/11/quantum*quantum))
  32       mem = (char*)mmap(NULL, memsz, PROT_WRITE, MAP_PRIVATE|MAP_ANON, -1, 0);
  33     assert(mem != MAP_FAILED);
  34     fprintf(stderr, "warning: only got %lu bytes of target mem (wanted %lu)\n",
  35             (unsigned long)memsz, (unsigned long)memsz0);
  36   }
  37
  38   mmu = new mmu_t(mem, memsz);
  39
  40   for(size_t i = 0; i < num_cores(); i++)
  41     procs[i] = new processor_t(this, new mmu_t(mem, memsz), i);
  42
  43   htif->init(this);
  44 }
  45
  46 sim_t::~sim_t()
  47 {
  48   for(size_t i = 0; i < num_cores(); i++)
  49   {
  50     mmu_t* pmmu = &procs[i]->mmu;
  51     delete procs[i];
  52     delete pmmu;
  53   }
  54   delete mmu;
  55   munmap(mem, memsz);
  56 }
  57
  58 void sim_t::send_ipi(reg_t who)
  59 {
  60   if(who < num_cores())
  61     procs[who]->deliver_ipi();
  62 }
  63
  64 void sim_t::run(bool debug)
  65 {
  66   // word 0 of memory contains the memory capacity in MB
  67   mmu->store_uint32(0, memsz >> 20);
  68   // word 1 of memory contains the core count
  69   mmu->store_uint32(4, num_cores());
  70
  71   htif->wait_for_start();
  72
  73   for(running = true; running; )
  74   {
  75     if(!debug)
  76       step_all(10000, 100, false);
  77     else
  78       interactive();
  79   }
  80 }
  81
  82 void sim_t::step_all(size_t n, size_t interleave, bool noisy)
  83 {
  84   for(size_t j = 0; j < n; j+=interleave)
  85   {
  86     if (steps % 16384 + interleave >= 16384)
  87       htif->wait_for_packet();
  88     steps += interleave;
  89     for(int i = 0; i < (int)num_cores(); i++)
  90       procs[i]->step(interleave,noisy);
  91   }
  92 }