// https://github.com/cnlohr/mini-rv32ima/blob/master/mini-rv32ima/mini-rv32ima.h
// Copyright 2022 Charles Lohr, you may use this file or any portions herein under any of the BSD, MIT, or CC0 licenses.
// 23.01.15 converted to Arduino by mchris

#ifndef _MINI_RV32IMAH_H
#define _MINI_RV32IMAH_H

/**
  To use mini-rv32ima.h for the bare minimum, the following:

  #define MINI_RV32_RAM_SIZE ram_amt

  #include "mini-rv32ima.h"

  Though, that's not _that_ interesting. You probably want I/O!


  Notes:
    * There is a dedicated CLNT at 0x10000000.
    * There is free MMIO from there to 0x12000000.
    * You can put things like a UART, or whatever there.
    * Feel free to override any of the functionality with macros.
*/

#define MINI_RV32_RAM_SIZE 200

#ifndef MINIRV32WARN
  #define MINIRV32WARN( x... );
#endif

#ifndef MINIRV32_DECORATE
  #define MINIRV32_DECORATE //static
#endif

#ifndef MINIRV32_RAM_IMAGE_OFFSET
  #define MINIRV32_RAM_IMAGE_OFFSET  0x80000000
#endif

#ifndef MINIRV32_POSTEXEC
  #define MINIRV32_POSTEXEC(...);
#endif

#ifndef MINIRV32_HANDLE_MEM_STORE_CONTROL
  #define MINIRV32_HANDLE_MEM_STORE_CONTROL(...);
#endif

#ifndef MINIRV32_HANDLE_MEM_LOAD_CONTROL
  #define MINIRV32_HANDLE_MEM_LOAD_CONTROL(...);
#endif

#ifndef MINIRV32_OTHERCSR_WRITE
  #define MINIRV32_OTHERCSR_WRITE(...);
#endif

#ifndef MINIRV32_OTHERCSR_READ
  #define MINIRV32_OTHERCSR_READ(...);
#endif

#ifndef MINIRV32_CUSTOM_MEMORY_BUS
  #define MINIRV32_STORE4( ofs, val ) *(uint32_t*)(image + ofs) = val
  #define MINIRV32_STORE2( ofs, val ) *(uint16_t*)(image + ofs) = val
  #define MINIRV32_STORE1( ofs, val ) *(uint8_t*)(image + ofs) = val
  #define MINIRV32_LOAD4( ofs ) *(uint32_t*)(image + ofs)
  #define MINIRV32_LOAD2( ofs ) *(uint16_t*)(image + ofs)
  #define MINIRV32_LOAD1( ofs ) *(uint8_t*)(image + ofs)
#endif

#define CSR( x ) state->x
#define SETCSR( x, val ) { state->x = val; }
#define REG( x ) state->regs[x]
#define REGSET( x, val ) { state->regs[x] = val; }

// As a note: We quouple-ify these, because in HLSL, we will be operating with
// uint4's.  We are going to uint4 data to/from system RAM.
//
// We're going to try to keep the full processor state to 12 x uint4.
struct MiniRV32IMAState
{
  uint32_t regs[32];

  uint32_t pc;
  uint32_t mstatus;
  uint32_t cyclel;
  uint32_t cycleh;

  uint32_t timerl;
  uint32_t timerh;
  uint32_t timermatchl;
  uint32_t timermatchh;

  uint32_t mscratch;
  uint32_t mtvec;
  uint32_t mie;
  uint32_t mip;

  uint32_t mepc;
  uint32_t mtval;
  uint32_t mcause;

  // Note: only a few bits are used.  (Machine = 3, User = 0)
  // Bits 0..1 = privilege.
  // Bit 2 = WFI (Wait for interrupt)
  // Bit 3 = Load/Store has a reservation.
  uint32_t extraflags;
};


MINIRV32_DECORATE int32_t RiscV_execute( struct MiniRV32IMAState * state, uint8_t * image, uint32_t vProcAddress, uint32_t elapsedUs, int count );

#endif