sim-core.c

这个是LINUX下的GDB调度工具的源码

/* The common simulator framework for GDB, the GNU Debugger.

   Copyright 2002 Free Software Foundation, Inc.

   Contributed by Andrew Cagney and Red Hat.

   This file is part of GDB.

   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 2 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, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */


#ifndef SIM_CORE_C
#define SIM_CORE_C

#include "sim-main.h"
#include "sim-assert.h"

#if (WITH_HW)
#include "sim-hw.h"
#endif

/* "core" module install handler.

   This is called via sim_module_install to install the "core"
   subsystem into the simulator.  */

#if EXTERN_SIM_CORE_P
static MODULE_INIT_FN sim_core_init;
static MODULE_UNINSTALL_FN sim_core_uninstall;
#endif

#if EXTERN_SIM_CORE_P
SIM_RC
sim_core_install (SIM_DESC sd)
{
  SIM_ASSERT (STATE_MAGIC (sd) == SIM_MAGIC_NUMBER);

  /* establish the other handlers */
  sim_module_add_uninstall_fn (sd, sim_core_uninstall);
  sim_module_add_init_fn (sd, sim_core_init);

  /* establish any initial data structures - none */
  return SIM_RC_OK;
}
#endif


/* Uninstall the "core" subsystem from the simulator.  */

#if EXTERN_SIM_CORE_P
static void
sim_core_uninstall (SIM_DESC sd)
{
  sim_core *core = STATE_CORE(sd);
  unsigned map;
  /* blow away any mappings */
  for (map = 0; map < nr_maps; map++) {
    sim_core_mapping *curr = core->common.map[map].first;
    while (curr != NULL) {
      sim_core_mapping *tbd = curr;
      curr = curr->next;
      if (tbd->free_buffer != NULL) {
	SIM_ASSERT(tbd->buffer != NULL);
	zfree(tbd->free_buffer);
      }
      zfree(tbd);
    }
    core->common.map[map].first = NULL;
  }
}
#endif


#if EXTERN_SIM_CORE_P
static SIM_RC
sim_core_init (SIM_DESC sd)
{
  /* Nothing to do */
  return SIM_RC_OK;
}
#endif



#ifndef SIM_CORE_SIGNAL
#define SIM_CORE_SIGNAL(SD,CPU,CIA,MAP,NR_BYTES,ADDR,TRANSFER,ERROR) \
sim_core_signal ((SD), (CPU), (CIA), (MAP), (NR_BYTES), (ADDR), (TRANSFER), (ERROR))
#endif

#if EXTERN_SIM_CORE_P
void
sim_core_signal (SIM_DESC sd,
		 sim_cpu *cpu,
		 sim_cia cia,
		 unsigned map,
		 int nr_bytes,
		 address_word addr,
		 transfer_type transfer,
		 sim_core_signals sig)
{
  const char *copy = (transfer == read_transfer ? "read" : "write");
  address_word ip = CIA_ADDR (cia);
  switch (sig)
    {
    case sim_core_unmapped_signal:
      sim_io_eprintf (sd, "core: %d byte %s to unmapped address 0x%lx at 0x%lx\n",
		      nr_bytes, copy, (unsigned long) addr, (unsigned long) ip);
      sim_engine_halt (sd, cpu, NULL, cia, sim_stopped, SIM_SIGSEGV);
      break;
    case sim_core_unaligned_signal:
      sim_io_eprintf (sd, "core: %d byte misaligned %s to address 0x%lx at 0x%lx\n",
		      nr_bytes, copy, (unsigned long) addr, (unsigned long) ip);
      sim_engine_halt (sd, cpu, NULL, cia, sim_stopped, SIM_SIGBUS);
      break;
    default:
      sim_engine_abort (sd, cpu, cia,
			"sim_core_signal - internal error - bad switch");
    }
}
#endif


#if EXTERN_SIM_CORE_P
static sim_core_mapping *
new_sim_core_mapping (SIM_DESC sd,
		      int level,
		      int space,
		      address_word addr,
		      address_word nr_bytes,
		      unsigned modulo,
#if WITH_HW
		      struct hw *device,
#else
		      device *device,
#endif
		      void *buffer,
		      void *free_buffer)
{
  sim_core_mapping *new_mapping = ZALLOC(sim_core_mapping);
  /* common */
  new_mapping->level = level;
  new_mapping->space = space;
  new_mapping->base = addr;
  new_mapping->nr_bytes = nr_bytes;
  new_mapping->bound = addr + (nr_bytes - 1);
  if (modulo == 0)
    new_mapping->mask = (unsigned) 0 - 1;
  else
    new_mapping->mask = modulo - 1;
  new_mapping->buffer = buffer;
  new_mapping->free_buffer = free_buffer;
  new_mapping->device = device;
  return new_mapping;
}
#endif


#if EXTERN_SIM_CORE_P
static void
sim_core_map_attach (SIM_DESC sd,
		     sim_core_map *access_map,
		     int level,
		     int space,
		     address_word addr,
		     address_word nr_bytes,
		     unsigned modulo,
#if WITH_HW
		     struct hw *client, /*callback/default*/
#else
		     device *client, /*callback/default*/
#endif
		     void *buffer, /*raw_memory*/
		     void *free_buffer) /*raw_memory*/
{
  /* find the insertion point for this additional mapping and then
     insert */
  sim_core_mapping *next_mapping;
  sim_core_mapping **last_mapping;

  SIM_ASSERT ((client == NULL) != (buffer == NULL));
  SIM_ASSERT ((client == NULL) >= (free_buffer != NULL));

  /* actually do occasionally get a zero size map */
  if (nr_bytes == 0)
    {
#if (WITH_DEVICES)
      device_error(client, "called on sim_core_map_attach with size zero");
#endif
#if (WITH_HW)
      sim_hw_abort (sd, client, "called on sim_core_map_attach with size zero");
#endif
      sim_io_error (sd, "called on sim_core_map_attach with size zero");
    }

  /* find the insertion point (between last/next) */
  next_mapping = access_map->first;
  last_mapping = &access_map->first;
  while(next_mapping != NULL
	&& (next_mapping->level < level
	    || (next_mapping->level == level
		&& next_mapping->bound < addr)))
    {
      /* provided levels are the same */
      /* assert: next_mapping->base > all bases before next_mapping */
      /* assert: next_mapping->bound >= all bounds before next_mapping */
      last_mapping = &next_mapping->next;
      next_mapping = next_mapping->next;
    }
  
  /* check insertion point correct */
  SIM_ASSERT (next_mapping == NULL || next_mapping->level >= level);
  if (next_mapping != NULL && next_mapping->level == level
      && next_mapping->base < (addr + (nr_bytes - 1)))
    {
#if (WITH_DEVICES)
      device_error (client, "memory map %d:0x%lx..0x%lx (%ld bytes) overlaps %d:0x%lx..0x%lx (%ld bytes)",
		    space,
		    (long) addr,
		    (long) (addr + nr_bytes - 1),
		    (long) nr_bytes,
		    next_mapping->space,
		    (long) next_mapping->base,
		    (long) next_mapping->bound,
		    (long) next_mapping->nr_bytes);
#endif
#if WITH_HW
      sim_hw_abort (sd, client, "memory map %d:0x%lx..0x%lx (%ld bytes) overlaps %d:0x%lx..0x%lx (%ld bytes)",
		    space,
		    (long) addr,
		    (long) (addr + (nr_bytes - 1)),
		    (long) nr_bytes,
		    next_mapping->space,
		    (long) next_mapping->base,
		    (long) next_mapping->bound,
		    (long) next_mapping->nr_bytes);
#endif
      sim_io_error (sd, "memory map %d:0x%lx..0x%lx (%ld bytes) overlaps %d:0x%lx..0x%lx (%ld bytes)",
		    space,
		    (long) addr,
		    (long) (addr + (nr_bytes - 1)),
		    (long) nr_bytes,
		    next_mapping->space,
		    (long) next_mapping->base,
		    (long) next_mapping->bound,
		    (long) next_mapping->nr_bytes);
  }

  /* create/insert the new mapping */
  *last_mapping = new_sim_core_mapping(sd,
				       level,
				       space, addr, nr_bytes, modulo,
				       client, buffer, free_buffer);
  (*last_mapping)->next = next_mapping;
}
#endif


/* Attach memory or a memory mapped device to the simulator.
   See sim-core.h for a full description.  */

#if EXTERN_SIM_CORE_P
void
sim_core_attach (SIM_DESC sd,
		 sim_cpu *cpu,
		 int level,
		 unsigned mapmask,
		 int space,
		 address_word addr,
		 address_word nr_bytes,
		 unsigned modulo,
#if WITH_HW
		 struct hw *client,
#else
		 device *client,
#endif
		 void *optional_buffer)
{
  sim_core *memory = STATE_CORE(sd);
  unsigned map;
  void *buffer;
  void *free_buffer;

  /* check for for attempt to use unimplemented per-processor core map */
  if (cpu != NULL)
    sim_io_error (sd, "sim_core_map_attach - processor specific memory map not yet supported");

  /* verify modulo memory */
  if (!WITH_MODULO_MEMORY && modulo != 0)
    {
#if (WITH_DEVICES)
      device_error (client, "sim_core_attach - internal error - modulo memory disabled");
#endif
#if (WITH_HW)
      sim_hw_abort (sd, client, "sim_core_attach - internal error - modulo memory disabled");
#endif
      sim_io_error (sd, "sim_core_attach - internal error - modulo memory disabled");
    }
  if (client != NULL && modulo != 0)
    {
#if (WITH_DEVICES)
      device_error (client, "sim_core_attach - internal error - modulo and callback memory conflict");
#endif
#if (WITH_HW)
      sim_hw_abort (sd, client, "sim_core_attach - internal error - modulo and callback memory conflict");
#endif
      sim_io_error (sd, "sim_core_attach - internal error - modulo and callback memory conflict");
    }
  if (modulo != 0)
    {
      unsigned mask = modulo - 1;
      /* any zero bits */
      while (mask >= sizeof (unsigned64)) /* minimum modulo */
	{
	  if ((mask & 1) == 0)
	    mask = 0;
	  else
	    mask >>= 1;
	}
      if (mask != sizeof (unsigned64) - 1)
	{
#if (WITH_DEVICES)
	  device_error (client, "sim_core_attach - internal error - modulo %lx not power of two", (long) modulo);
#endif
#if (WITH_HW)
	  sim_hw_abort (sd, client, "sim_core_attach - internal error - modulo %lx not power of two", (long) modulo);
#endif
	  sim_io_error (sd, "sim_core_attach - internal error - modulo %lx not power of two", (long) modulo);
	}
    }

  /* verify consistency between device and buffer */
  if (client != NULL && optional_buffer != NULL)
    {
#if (WITH_DEVICES)
      device_error (client, "sim_core_attach - internal error - conflicting buffer and attach arguments");
#endif
#if (WITH_HW)
      sim_hw_abort (sd, client, "sim_core_attach - internal error - conflicting buffer and attach arguments");
#endif
      sim_io_error (sd, "sim_core_attach - internal error - conflicting buffer and attach arguments");
    }
  if (client == NULL)
    {
      if (optional_buffer == NULL)
	{
	  int padding = (addr % sizeof (unsigned64));
	  unsigned long bytes = (modulo == 0 ? nr_bytes : modulo) + padding;
	  free_buffer = zalloc (bytes);
	  buffer = (char*) free_buffer + padding;
	}
      else
	{
	  buffer = optional_buffer;
	  free_buffer = NULL;
	}
    }
  else
    {
      /* a device */
      buffer = NULL;
      free_buffer = NULL;
    }

  /* attach the region to all applicable access maps */
  for (map = 0; 
       map < nr_maps;
       map++)
    {
      if (mapmask & (1 << map))
	{
	  sim_core_map_attach (sd, &memory->common.map[map],
			       level, space, addr, nr_bytes, modulo,
			       client, buffer, free_buffer);
	  free_buffer = NULL;
	}
    }
  
  /* Just copy this map to each of the processor specific data structures.
     FIXME - later this will be replaced by true processor specific
     maps. */
  {
    int i;
    for (i = 0; i < MAX_NR_PROCESSORS; i++)
      {
	CPU_CORE (STATE_CPU (sd, i))->common = STATE_CORE (sd)->common;
      }
  }
}
#endif


/* Remove any memory reference related to this address */
#if EXTERN_SIM_CORE_P
static void
sim_core_map_detach (SIM_DESC sd,
		     sim_core_map *access_map,
		     int level,
		     int space,
		     address_word addr)
{
  sim_core_mapping **entry;
  for (entry = &access_map->first;
       (*entry) != NULL;
       entry = &(*entry)->next)
    {
      if ((*entry)->base == addr
	  && (*entry)->level == level
	  && (*entry)->space == space)
	{
	  sim_core_mapping *dead = (*entry);
	  (*entry) = dead->next;
	  if (dead->free_buffer != NULL)
	    zfree (dead->free_buffer);
	  zfree (dead);
	  return;
	}
    }