/* mem.c --- memory for RX simulator.

Copyright (C) 2005, 2007, 2008, 2009 Free Software Foundation, Inc.
Contributed by Red Hat, Inc.

This file is part of the GNU simulators.

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

/* This slows down the simulator and we get some false negatives from
   gcc, like when it uses a long-sized hole to hold a byte-sized
   variable, knowing that it doesn't care about the other bits.  But,
   if you need to track down a read-from-unitialized bug, set this to
   1.  */
#define RDCHECK 0

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "mem.h"
#include "cpu.h"
#include "syscalls.h"
#include "misc.h"
#include "err.h"

#define L1_BITS  (10)
#define L2_BITS  (10)
#define OFF_BITS (12)

#define L1_LEN  (1 << L1_BITS)
#define L2_LEN  (1 << L2_BITS)
#define OFF_LEN (1 << OFF_BITS)

static unsigned char **pt[L1_LEN];
static unsigned char **ptr[L1_LEN];

/* [ get=0/put=1 ][ byte size ] */
static unsigned int mem_counters[2][5];

#define COUNT(isput,bytes)                                      \
  if (verbose && enable_counting) mem_counters[isput][bytes]++

void
init_mem (void)
{
  int i, j;

  for (i = 0; i < L1_LEN; i++)
    if (pt[i])
      {
	for (j = 0; j < L2_LEN; j++)
	  if (pt[i][j])
	    free (pt[i][j]);
	free (pt[i]);
      }
  memset (pt, 0, sizeof (pt));
  memset (ptr, 0, sizeof (ptr));
  memset (mem_counters, 0, sizeof (mem_counters));
}

enum mem_ptr_action
{
  MPA_WRITING,
  MPA_READING,
  MPA_CONTENT_TYPE
};

static unsigned char *
mem_ptr (unsigned long address, enum mem_ptr_action action)
{
  int pt1 = (address >> (L2_BITS + OFF_BITS)) & ((1 << L1_BITS) - 1);
  int pt2 = (address >> OFF_BITS) & ((1 << L2_BITS) - 1);
  int pto = address & ((1 << OFF_BITS) - 1);

  if (address == 0)
    execution_error (SIM_ERR_NULL_POINTER_DEREFERENCE, 0);

  if (pt[pt1] == 0)
    {
      pt[pt1] = (unsigned char **) calloc (L2_LEN, sizeof (char **));
      ptr[pt1] = (unsigned char **) calloc (L2_LEN, sizeof (char **));
    }
  if (pt[pt1][pt2] == 0)
    {
      if (action == MPA_READING)
	execution_error (SIM_ERR_READ_UNWRITTEN_PAGES, address);

      pt[pt1][pt2] = (unsigned char *) malloc (OFF_LEN);
      memset (pt[pt1][pt2], 0, OFF_LEN);
      ptr[pt1][pt2] = (unsigned char *) malloc (OFF_LEN);
      memset (ptr[pt1][pt2], MC_UNINIT, OFF_LEN);
    }
  else if (action == MPA_READING
	   && ptr[pt1][pt2][pto] == MC_UNINIT)
    execution_error (SIM_ERR_READ_UNWRITTEN_BYTES, address);

  if (action == MPA_WRITING)
    {
      if (ptr[pt1][pt2][pto] == MC_PUSHED_PC)
	execution_error (SIM_ERR_CORRUPT_STACK, address);
      ptr[pt1][pt2][pto] = MC_DATA;
    }

  if (action == MPA_CONTENT_TYPE)
    return ptr[pt1][pt2] + pto;

  return pt[pt1][pt2] + pto;
}

static inline int
is_reserved_address (unsigned int address)
{
  return (address >= 0x00020000 && address < 0x00080000)
    ||   (address >= 0x00100000 && address < 0x01000000)
    ||   (address >= 0x08000000 && address < 0xff000000);
}

static void
used (int rstart, int i, int j)
{
  int rend = i << (L2_BITS + OFF_BITS);
  rend += j << OFF_BITS;
  if (rstart == 0xe0000 && rend == 0xe1000)
    return;
  printf ("mem:   %08x - %08x (%dk bytes)\n", rstart, rend - 1,
	  (rend - rstart) / 1024);
}

static char *
mcs (int isput, int bytes)
{
  return comma (mem_counters[isput][bytes]);
}

void
mem_usage_stats ()
{
  int i, j;
  int rstart = 0;
  int pending = 0;

  for (i = 0; i < L1_LEN; i++)
    if (pt[i])
      {
	for (j = 0; j < L2_LEN; j++)
	  if (pt[i][j])
	    {
	      if (!pending)
		{
		  pending = 1;
		  rstart = (i << (L2_BITS + OFF_BITS)) + (j << OFF_BITS);
		}
	    }
	  else if (pending)
	    {
	      pending = 0;
	      used (rstart, i, j);
	    }
      }
    else
      {
	if (pending)
	  {
	    pending = 0;
	    used (rstart, i, 0);
	  }
      }
  /*       mem foo: 123456789012 123456789012 123456789012 123456789012
            123456789012 */
  printf ("                 byte        short        3byte         long"
          "       opcode\n");
  if (verbose > 1)
    {
      /* Only use comma separated numbers when being very verbose.
	 Comma separated numbers are hard to parse in awk scripts.  */
      printf ("mem get: %12s %12s %12s %12s %12s\n", mcs (0, 1), mcs (0, 2),
	      mcs (0, 3), mcs (0, 4), mcs (0, 0));
      printf ("mem put: %12s %12s %12s %12s\n", mcs (1, 1), mcs (1, 2),
	      mcs (1, 3), mcs (1, 4));
    }
  else
    {
      printf ("mem get: %12u %12u %12u %12u %12u\n",
	      mem_counters[0][1], mem_counters[0][2],
	      mem_counters[0][3], mem_counters[0][4],
	      mem_counters[0][0]);
      printf ("mem put: %12u %12u %12u %12u\n",
	      mem_counters [1][1], mem_counters [1][2],
	      mem_counters [1][3], mem_counters [1][4]);
    }
}

unsigned long
mem_usage_cycles (void)
{
  unsigned long rv = mem_counters[0][0];
  rv += mem_counters[0][1] * 1;
  rv += mem_counters[0][2] * 2;
  rv += mem_counters[0][3] * 3;
  rv += mem_counters[0][4] * 4;
  rv += mem_counters[1][1] * 1;
  rv += mem_counters[1][2] * 2;
  rv += mem_counters[1][3] * 3;
  rv += mem_counters[1][4] * 4;
  return rv;
}

static int tpr = 0;
static void
s (int address, char *dir)
{
  if (tpr == 0)
    printf ("MEM[%08x] %s", address, dir);
  tpr++;
}

#define S(d) if (trace) s(address, d)
static void
e ()
{
  if (!trace)
    return;
  tpr--;
  if (tpr == 0)
    printf ("\n");
}

static char
mtypec (int address)
{
  unsigned char *cp = mem_ptr (address, MPA_CONTENT_TYPE);
  return "udp"[*cp];
}

#define E() if (trace) e()

void
mem_put_byte (unsigned int address, unsigned char value)
{
  unsigned char *m;
  char tc = ' ';

  if (trace)
    tc = mtypec (address);
  m = mem_ptr (address, MPA_WRITING);
  if (trace)
    printf (" %02x%c", value, tc);
  *m = value;
  switch (address)
    {
    case 0x00e1:
      {
	static int old_led = -1;
	static char *led_on[] =
	  { "\033[31m O ", "\033[32m O ", "\033[34m O " };
	static char *led_off[] = { "\033[0m · ", "\033[0m · ", "\033[0m · " };
	int i;
	if (old_led != value)
	  {
	    fputs ("  ", stdout);
	    for (i = 0; i < 3; i++)
	      if (value & (1 << i))
		fputs (led_off[i], stdout);
	      else
		fputs (led_on[i], stdout);
	    fputs ("\033[0m\r", stdout);
	    fflush (stdout);
	    old_led = value;
	  }
      }
      break;

    case 0x3aa: /* uart1tx */
      {
	static int pending_exit = 0;
	if (value == 0)
	  {
	    if (pending_exit)
	      {
		step_result = RX_MAKE_EXITED(value);
		return;
	      }
	    pending_exit = 1;
	  }
	else
	  putchar(value);
      }
      break;

    default:
      if (is_reserved_address (address))
	generate_access_exception ();
    }
}

void
mem_put_qi (int address, unsigned char value)
{
  S ("<=");
  mem_put_byte (address, value & 0xff);
  E ();
  COUNT (1, 1);
}

void
mem_put_hi (int address, unsigned short value)
{
  S ("<=");
  if (rx_big_endian)
    {
      mem_put_byte (address, value >> 8);
      mem_put_byte (address + 1, value & 0xff);
    }
  else
    {
      mem_put_byte (address, value & 0xff);
      mem_put_byte (address + 1, value >> 8);
    }
  E ();
  COUNT (1, 2);
}

void
mem_put_psi (int address, unsigned long value)
{
  S ("<=");
  if (rx_big_endian)
    {
      mem_put_byte (address, value >> 16);
      mem_put_byte (address + 1, (value >> 8) & 0xff);
      mem_put_byte (address + 2, value & 0xff);
    }
  else
    {
      mem_put_byte (address, value & 0xff);
      mem_put_byte (address + 1, (value >> 8) & 0xff);
      mem_put_byte (address + 2, value >> 16);
    }
  E ();
  COUNT (1, 3);
}

void
mem_put_si (int address, unsigned long value)
{
  S ("<=");
  if (rx_big_endian)
    {
      mem_put_byte (address + 0, (value >> 24) & 0xff);
      mem_put_byte (address + 1, (value >> 16) & 0xff);
      mem_put_byte (address + 2, (value >> 8) & 0xff);
      mem_put_byte (address + 3, value & 0xff);
    }
  else
    {
      mem_put_byte (address + 0, value & 0xff);
      mem_put_byte (address + 1, (value >> 8) & 0xff);
      mem_put_byte (address + 2, (value >> 16) & 0xff);
      mem_put_byte (address + 3, (value >> 24) & 0xff);
    }
  E ();
  COUNT (1, 4);
}

void
mem_put_blk (int address, void *bufptr, int nbytes)
{
  S ("<=");
  if (enable_counting)
    mem_counters[1][1] += nbytes;
  while (nbytes--)
    mem_put_byte (address++, *(unsigned char *) bufptr++);
  E ();
}

unsigned char
mem_get_pc (int address)
{
  unsigned char *m = mem_ptr (address, MPA_READING);
  COUNT (0, 0);
  return *m;
}

static unsigned char
mem_get_byte (unsigned int address)
{
  unsigned char *m;

  S ("=>");
  m = mem_ptr (address, MPA_READING);
  switch (address)
    {
    case 0x3ad: /* uart1c1 */
      E();
      return 2; /* transmitter empty */
      break;
    default: 
      if (trace)
	printf (" %02x%c", *m, mtypec (address));
      if (is_reserved_address (address))
	generate_access_exception ();
      break;
    }
  E ();
  return *m;
}

unsigned char
mem_get_qi (int address)
{
  unsigned char rv;
  S ("=>");
  rv = mem_get_byte (address);
  COUNT (0, 1);
  E ();
  return rv;
}

unsigned short
mem_get_hi (int address)
{
  unsigned short rv;
  S ("=>");
  if (rx_big_endian)
    {
      rv = mem_get_byte (address) << 8;
      rv |= mem_get_byte (address + 1);
    }
  else
    {
      rv = mem_get_byte (address);
      rv |= mem_get_byte (address + 1) << 8;
    }
  COUNT (0, 2);
  E ();
  return rv;
}

unsigned long
mem_get_psi (int address)
{
  unsigned long rv;
  S ("=>");
  if (rx_big_endian)
    {
      rv = mem_get_byte (address + 2);
      rv |= mem_get_byte (address + 1) << 8;
      rv |= mem_get_byte (address) << 16;
    }
  else
    {
      rv = mem_get_byte (address);
      rv |= mem_get_byte (address + 1) << 8;
      rv |= mem_get_byte (address + 2) << 16;
    }
  COUNT (0, 3);
  E ();
  return rv;
}

unsigned long
mem_get_si (int address)
{
  unsigned long rv;
  S ("=>");
  if (rx_big_endian)
    {
      rv = mem_get_byte (address + 3);
      rv |= mem_get_byte (address + 2) << 8;
      rv |= mem_get_byte (address + 1) << 16;
      rv |= mem_get_byte (address) << 24;
    }
  else
    {
      rv = mem_get_byte (address);
      rv |= mem_get_byte (address + 1) << 8;
      rv |= mem_get_byte (address + 2) << 16;
      rv |= mem_get_byte (address + 3) << 24;
    }
  COUNT (0, 4);
  E ();
  return rv;
}

void
mem_get_blk (int address, void *bufptr, int nbytes)
{
  S ("=>");
  if (enable_counting)
    mem_counters[0][1] += nbytes;
  while (nbytes--)
    *(char *) bufptr++ = mem_get_byte (address++);
  E ();
}

int
sign_ext (int v, int bits)
{
  if (bits < 32)
    {
      v &= (1 << bits) - 1;
      if (v & (1 << (bits - 1)))
	v -= (1 << bits);
    }
  return v;
}

void
mem_set_content_type (int address, enum mem_content_type type)
{
  unsigned char *mt = mem_ptr (address, MPA_CONTENT_TYPE);
  *mt = type;
}

void
mem_set_content_range (int start_address, int end_address, enum mem_content_type type)
{
  while (start_address < end_address)
    {
      int sz, ofs;
      unsigned char *mt;

      sz = end_address - start_address;
      ofs = start_address % L1_LEN;
      if (sz + ofs > L1_LEN)
	sz = L1_LEN - ofs;

      mt = mem_ptr (start_address, MPA_CONTENT_TYPE);
      memset (mt, type, sz);

      start_address += sz;
    }
}

enum mem_content_type
mem_get_content_type (int address)
{
  unsigned char *mt = mem_ptr (address, MPA_CONTENT_TYPE);
  return *mt;
}