riscv/mmu.h

   1 #include "decode.h"
   2 #include "trap.h"
   3
   4 class mmu_t
   5 {
   6 public:
   7   mmu_t(char* _mem, size_t _memsz) : mem(_mem), memsz(_memsz), badvaddr(0) {}
   8
   9   #define load_func(type) \
  10     type##_t load_##type(reg_t addr) { \
  11       check_align_and_bounds(addr, sizeof(type##_t), false, false); \
  12       return *(type##_t*)(mem+addr); \
  13     }
  14
  15   #define store_func(type) \
  16     void store_##type(reg_t addr, type##_t val) { \
  17       check_align_and_bounds(addr, sizeof(type##_t), true, false); \
  18       *(type##_t*)(mem+addr) = val; \
  19     }
  20
  21   insn_t load_insn(reg_t addr, bool rvc)
  22   {
  23     check_align_and_bounds(addr, rvc ? 2 : 4, false, true);
  24     uint16_t lo = *(uint16_t*)(mem+addr);
  25     uint16_t hi = *(uint16_t*)(mem+addr+2);
  26
  27     insn_t insn;
  28     insn.bits = ((uint32_t)hi << 16) | lo;
  29     return insn;
  30   }
  31
  32   load_func(uint8)
  33   load_func(uint16)
  34   load_func(uint32)
  35   load_func(uint64)
  36
  37   load_func(int8)
  38   load_func(int16)
  39   load_func(int32)
  40   load_func(int64)
  41
  42   store_func(uint8)
  43   store_func(uint16)
  44   store_func(uint32)
  45   store_func(uint64)
  46
  47   reg_t get_badvaddr() { return badvaddr; }
  48
  49 private:
  50   char* mem;
  51   size_t memsz;
  52   reg_t badvaddr;
  53
  54   void check_align(reg_t addr, int size, bool fetch)
  55   {
  56     if(addr & (size-1))
  57     {
  58       badvaddr = addr;
  59       if(fetch)
  60         throw trap_instruction_address_misaligned;
  61       throw trap_data_address_misaligned;
  62     }
  63   }
  64
  65   void check_bounds(reg_t addr, int size, bool store, bool fetch)
  66   {
  67     if(addr >= memsz || addr + size > memsz)
  68     {
  69       badvaddr = addr;
  70       if(fetch)
  71         throw trap_instruction_access_fault;
  72       throw store ? trap_store_access_fault : trap_load_access_fault;
  73     }
  74   }
  75
  76   void check_align_and_bounds(reg_t addr, int size, bool store, bool fetch)
  77   {
  78     check_align(addr, size, fetch);
  79     check_bounds(addr, size, store, fetch);
  80   }
  81 };