binutils-gdb/sim/m68hc11/dv-nvram.c
Mike Frysinger 6df01ab8ab sim: switch config.h usage to defs.h
The defs.h header will take care of including the various config.h
headers.  For now, it's just config.h, but we'll add more when we
integrate gnulib in.

This header should be used instead of config.h, and should be the
first include in every .c file.  We won't rely on the old behavior
where we expected files to include the port's sim-main.h which then
includes the common sim-basics.h which then includes config.h.  We
have a ton of code that includes things before sim-main.h, and it
sometimes needs to be that way.  Creating a dedicated header avoids
the ordering mess and implicit inclusion that shows up otherwise.
2021-05-16 22:38:41 -04:00

353 lines
9.6 KiB
C

/* dv-nvram.c -- Generic driver for a non volatile ram (battery saved)
Copyright (C) 1999-2021 Free Software Foundation, Inc.
Written by Stephane Carrez (stcarrez@worldnet.fr)
(From a driver model Contributed by Cygnus Solutions.)
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 must come before any other includes. */
#include "defs.h"
#include "sim-main.h"
#include "hw-main.h"
#include "sim-assert.h"
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
/* DEVICE
nvram - Non Volatile Ram
DESCRIPTION
Implements a generic battery saved CMOS ram. This ram device does
not contain any realtime clock and does not generate any interrupt.
The ram content is loaded from a file and saved when it is changed.
It is intended to be generic.
PROPERTIES
reg <base> <length>
Base and size of the non-volatile ram bank.
file <path>
Path where the memory must be saved or loaded when we start.
mode {map | save-modified | save-all}
Controls how to load and save the memory content.
map The file is mapped in memory
save-modified The simulator keeps an open file descriptor to
the file and saves portion of memory which are
modified.
save-all The simulator saves the complete memory each time
it's modified (it does not keep an open file
descriptor).
PORTS
None.
NOTES
This device is independent of the Motorola 68hc11.
*/
/* static functions */
/* Control of how to access the ram and save its content. */
enum nvram_mode
{
/* Save the complete ram block each time it's changed.
We don't keep an open file descriptor. This should be
ok for small memory banks. */
NVRAM_SAVE_ALL,
/* Save only the memory bytes which are modified.
This mode means that we have to keep an open file
descriptor (O_RDWR). It's good for middle sized memory banks. */
NVRAM_SAVE_MODIFIED,
/* Map file in memory (not yet implemented).
This mode is suitable for large memory banks. We don't allocate
a buffer to represent the ram, instead it's mapped in memory
with mmap. */
NVRAM_MAP_FILE
};
struct nvram
{
address_word base_address; /* Base address of ram. */
unsigned size; /* Size of ram. */
unsigned8 *data; /* Pointer to ram memory. */
const char *file_name; /* Path of ram file. */
int fd; /* File description of opened ram file. */
enum nvram_mode mode; /* How load/save ram file. */
};
/* Finish off the partially created hw device. Attach our local
callbacks. Wire up our port names etc. */
static hw_io_read_buffer_method nvram_io_read_buffer;
static hw_io_write_buffer_method nvram_io_write_buffer;
static void
attach_nvram_regs (struct hw *me, struct nvram *controller)
{
unsigned_word attach_address;
int attach_space;
unsigned attach_size;
reg_property_spec reg;
int result, oerrno;
/* Get ram bank description (base and size). */
if (hw_find_property (me, "reg") == NULL)
hw_abort (me, "Missing \"reg\" property");
if (!hw_find_reg_array_property (me, "reg", 0, &reg))
hw_abort (me, "\"reg\" property must contain one addr/size entry");
hw_unit_address_to_attach_address (hw_parent (me),
&reg.address,
&attach_space,
&attach_address,
me);
hw_unit_size_to_attach_size (hw_parent (me),
&reg.size,
&attach_size, me);
hw_attach_address (hw_parent (me), 0,
attach_space, attach_address, attach_size,
me);
controller->mode = NVRAM_SAVE_ALL;
controller->base_address = attach_address;
controller->size = attach_size;
controller->fd = -1;
/* Get the file where the ram content must be loaded/saved. */
if(hw_find_property (me, "file") == NULL)
hw_abort (me, "Missing \"file\" property");
controller->file_name = hw_find_string_property (me, "file");
/* Get the mode which defines how to save the memory. */
if(hw_find_property (me, "mode") != NULL)
{
const char *value = hw_find_string_property (me, "mode");
if (strcmp (value, "map") == 0)
controller->mode = NVRAM_MAP_FILE;
else if (strcmp (value, "save-modified") == 0)
controller->mode = NVRAM_SAVE_MODIFIED;
else if (strcmp (value, "save-all") == 0)
controller->mode = NVRAM_SAVE_ALL;
else
hw_abort (me, "illegal value for mode parameter `%s': "
"use map, save-modified or save-all", value);
}
/* Initialize the ram by loading/mapping the file in memory.
If the file does not exist, create and give it some content. */
switch (controller->mode)
{
case NVRAM_MAP_FILE:
hw_abort (me, "'map' mode is not yet implemented, use 'save-modified'");
break;
case NVRAM_SAVE_MODIFIED:
case NVRAM_SAVE_ALL:
controller->data = hw_malloc (me, attach_size);
if (controller->data == 0)
hw_abort (me, "Not enough memory, try to use the mode 'map'");
memset (controller->data, 0, attach_size);
controller->fd = open (controller->file_name, O_RDWR);
if (controller->fd < 0)
{
controller->fd = open (controller->file_name,
O_RDWR | O_CREAT, 0644);
if (controller->fd < 0)
hw_abort (me, "Cannot open or create file '%s'",
controller->file_name);
result = write (controller->fd, controller->data, attach_size);
if (result != attach_size)
{
oerrno = errno;
hw_free (me, controller->data);
close (controller->fd);
errno = oerrno;
hw_abort (me, "Failed to save the ram content");
}
}
else
{
result = read (controller->fd, controller->data, attach_size);
if (result != attach_size)
{
oerrno = errno;
hw_free (me, controller->data);
close (controller->fd);
errno = oerrno;
hw_abort (me, "Failed to load the ram content");
}
}
if (controller->mode == NVRAM_SAVE_ALL)
{
close (controller->fd);
controller->fd = -1;
}
break;
default:
break;
}
}
static void
nvram_finish (struct hw *me)
{
struct nvram *controller;
controller = HW_ZALLOC (me, struct nvram);
set_hw_data (me, controller);
set_hw_io_read_buffer (me, nvram_io_read_buffer);
set_hw_io_write_buffer (me, nvram_io_write_buffer);
/* Attach ourself to our parent bus. */
attach_nvram_regs (me, controller);
}
/* generic read/write */
static unsigned
nvram_io_read_buffer (struct hw *me,
void *dest,
int space,
unsigned_word base,
unsigned nr_bytes)
{
struct nvram *controller = hw_data (me);
HW_TRACE ((me, "read 0x%08lx %d [%ld]",
(long) base, (int) nr_bytes,
(long) (base - controller->base_address)));
base -= controller->base_address;
if (base + nr_bytes > controller->size)
nr_bytes = controller->size - base;
memcpy (dest, &controller->data[base], nr_bytes);
return nr_bytes;
}
static unsigned
nvram_io_write_buffer (struct hw *me,
const void *source,
int space,
unsigned_word base,
unsigned nr_bytes)
{
struct nvram *controller = hw_data (me);
HW_TRACE ((me, "write 0x%08lx %d [%ld]",
(long) base, (int) nr_bytes,
(long) (base - controller->base_address)));
base -= controller->base_address;
if (base + nr_bytes > controller->size)
nr_bytes = controller->size - base;
switch (controller->mode)
{
case NVRAM_SAVE_ALL:
{
int fd, result, oerrno;
fd = open (controller->file_name, O_WRONLY, 0644);
if (fd < 0)
{
return 0;
}
memcpy (&controller->data[base], source, nr_bytes);
result = write (fd, controller->data, controller->size);
oerrno = errno;
close (fd);
errno = oerrno;
if (result != controller->size)
{
return 0;
}
return nr_bytes;
}
case NVRAM_SAVE_MODIFIED:
{
off_t pos;
int result;
pos = lseek (controller->fd, (off_t) base, SEEK_SET);
if (pos != (off_t) base)
return 0;
result = write (controller->fd, source, nr_bytes);
if (result < 0)
return 0;
nr_bytes = result;
break;
}
default:
break;
}
memcpy (&controller->data[base], source, nr_bytes);
return nr_bytes;
}
const struct hw_descriptor dv_nvram_descriptor[] = {
{ "nvram", nvram_finish, },
{ NULL },
};