arch/sandbox/cpu/state.c - filogic/uboot - Gitiles

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * Copyright (c) 2011-2012 The Chromium OS Authors.
  */

 #include <common.h>
 #include <autoboot.h>
 #include <bloblist.h>
 #include <errno.h>
 #include <fdtdec.h>
 #include <log.h>
 #include <os.h>
 #include <asm/malloc.h>
 #include <asm/state.h>

 /* Main state record for the sandbox */
 static struct sandbox_state main_state;
 static struct sandbox_state *state;	/* Pointer to current state record */

 static int state_ensure_space(int extra_size)
 {
 	void *blob = state->state_fdt;
 	int used, size, free_bytes;
 	void *buf;
 	int ret;

 	used = fdt_off_dt_strings(blob) + fdt_size_dt_strings(blob);
 	size = fdt_totalsize(blob);
 	free_bytes = size - used;
 	if (free_bytes > extra_size)
 		return 0;

 	size = used + extra_size;
 	buf = os_malloc(size);
 	if (!buf)
 		return -ENOMEM;

 	ret = fdt_open_into(blob, buf, size);
 	if (ret) {
 		os_free(buf);
 		return -EIO;
 	}

 	os_free(blob);
 	state->state_fdt = buf;
 	return 0;
 }

 static int state_read_file(struct sandbox_state *state, const char *fname)
 {
 	loff_t size;
 	int ret;
 	int fd;

 	ret = os_get_filesize(fname, &size);
 	if (ret < 0) {
 		printf("Cannot find sandbox state file '%s'\n", fname);
 		return -ENOENT;
 	}
 	state->state_fdt = os_malloc(size);
 	if (!state->state_fdt) {
 		puts("No memory to read sandbox state\n");
 		return -ENOMEM;
 	}
 	fd = os_open(fname, OS_O_RDONLY);
 	if (fd < 0) {
 		printf("Cannot open sandbox state file '%s'\n", fname);
 		ret = -EPERM;
 		goto err_open;
 	}
 	if (os_read(fd, state->state_fdt, size) != size) {
 		printf("Cannot read sandbox state file '%s'\n", fname);
 		ret = -EIO;
 		goto err_read;
 	}
 	os_close(fd);

 	return 0;
 err_read:
 	os_close(fd);
 err_open:
 	/*
 	 * tainted scalar, since size is obtained from the file. But we can rely
 	 * on os_malloc() to handle invalid values.
 	 */
 	os_free(state->state_fdt);
 	state->state_fdt = NULL;

 	return ret;
 }

 /***
  * sandbox_read_state_nodes() - Read state associated with a driver
  *
  * This looks through all compatible nodes and calls the read function on
  * each one, to read in the state.
  *
  * If nothing is found, it still calls the read function once, to set up a
  * single global state for that driver.
  *
  * @state: Sandbox state
  * @io: Method to use for reading state
  * @blob: FDT containing state
  * Return: 0 if OK, -EINVAL if the read function returned failure
  */
 int sandbox_read_state_nodes(struct sandbox_state *state,
 			     struct sandbox_state_io *io, const void *blob)
 {
 	int count;
 	int node;
 	int ret;

 	debug("   - read %s\n", io->name);
 	if (!io->read)
 		return 0;

 	node = -1;
 	count = 0;
 	while (blob) {
 		node = fdt_node_offset_by_compatible(blob, node, io->compat);
 		if (node < 0)
 			return 0;	/* No more */
 		debug("   - read node '%s'\n", fdt_get_name(blob, node, NULL));
 		ret = io->read(blob, node);
 		if (ret) {
 			printf("Unable to read state for '%s'\n", io->compat);
 			return -EINVAL;
 		}
 		count++;
 	}

 	/*
 	 * If we got no saved state, call the read function once without a
 	 * node, to set up the global state.
 	 */
 	if (count == 0) {
 		debug("   - read global\n");
 		ret = io->read(NULL, -1);
 		if (ret) {
 			printf("Unable to read global state for '%s'\n",
 			       io->name);
 			return -EINVAL;
 		}
 	}

 	return 0;
 }

 int sandbox_read_state(struct sandbox_state *state, const char *fname)
 {
 	struct sandbox_state_io *io;
 	const void *blob;
 	bool got_err;
 	int ret;

 	if (state->read_state && fname) {
 		ret = state_read_file(state, fname);
 		if (ret == -ENOENT && state->ignore_missing_state_on_read)
 			ret = 0;
 		if (ret)
 			return ret;
 	}

 	/* Call all the state read functions */
 	got_err = false;
 	blob = state->state_fdt;
 	io = ll_entry_start(struct sandbox_state_io, state_io);
 	for (; io < ll_entry_end(struct sandbox_state_io, state_io); io++) {
 		ret = sandbox_read_state_nodes(state, io, blob);
 		if (ret < 0)
 			got_err = true;
 	}

 	if (state->read_state && fname) {
 		debug("Read sandbox state from '%s'%s\n", fname,
 		      got_err ? " (with errors)" : "");
 	}

 	return got_err ? -1 : 0;
 }

 /***
  * sandbox_write_state_node() - Write state associated with a driver
  *
  * This calls the write function to write out global state for that driver.
  *
  * TODO(sjg@chromium.org): Support writing out state from multiple drivers
  * of the same time. We don't need this yet,and it will be much easier to
  * do when driver model is available.
  *
  * @state: Sandbox state
  * @io: Method to use for writing state
  * Return: 0 if OK, -EIO if there is a fatal error (such as out of space
  * for adding the data), -EINVAL if the write function failed.
  */
 int sandbox_write_state_node(struct sandbox_state *state,
 			     struct sandbox_state_io *io)
 {
 	void *blob;
 	int node;
 	int ret;

 	if (!io->write)
 		return 0;

 	ret = state_ensure_space(SANDBOX_STATE_MIN_SPACE);
 	if (ret) {
 		printf("Failed to add more space for state\n");
 		return -EIO;
 	}

 	/* The blob location can change when the size increases */
 	blob = state->state_fdt;
 	node = fdt_node_offset_by_compatible(blob, -1, io->compat);
 	if (node == -FDT_ERR_NOTFOUND) {
 		node = fdt_add_subnode(blob, 0, io->name);
 		if (node < 0) {
 			printf("Cannot create node '%s': %s\n", io->name,
 			       fdt_strerror(node));
 			return -EIO;
 		}

 		if (fdt_setprop_string(blob, node, "compatible", io->compat)) {
 			puts("Cannot set compatible\n");
 			return -EIO;
 		}
 	} else if (node < 0) {
 		printf("Cannot access node '%s': %s\n", io->name,
 		       fdt_strerror(node));
 		return -EIO;
 	}
 	debug("Write state for '%s' to node %d\n", io->compat, node);
 	ret = io->write(blob, node);
 	if (ret) {
 		printf("Unable to write state for '%s'\n", io->compat);
 		return -EINVAL;
 	}

 	return 0;
 }

 int sandbox_write_state(struct sandbox_state *state, const char *fname)
 {
 	struct sandbox_state_io *io;
 	bool got_err;
 	int size;
 	int ret;
 	int fd;

 	/* Create a state FDT if we don't have one */
 	if (!state->state_fdt) {
 		size = 0x4000;
 		state->state_fdt = os_malloc(size);
 		if (!state->state_fdt) {
 			puts("No memory to create FDT\n");
 			return -ENOMEM;
 		}
 		ret = fdt_create_empty_tree(state->state_fdt, size);
 		if (ret < 0) {
 			printf("Cannot create empty state FDT: %s\n",
 			       fdt_strerror(ret));
 			ret = -EIO;
 			goto err_create;
 		}
 	}

 	/* Call all the state write funtcions */
 	got_err = false;
 	io = ll_entry_start(struct sandbox_state_io, state_io);
 	ret = 0;
 	for (; io < ll_entry_end(struct sandbox_state_io, state_io); io++) {
 		ret = sandbox_write_state_node(state, io);
 		if (ret == -EIO)
 			break;
 		else if (ret)
 			got_err = true;
 	}

 	if (ret == -EIO) {
 		printf("Could not write sandbox state\n");
 		goto err_create;
 	}

 	ret = fdt_pack(state->state_fdt);
 	if (ret < 0) {
 		printf("Cannot pack state FDT: %s\n", fdt_strerror(ret));
 		ret = -EINVAL;
 		goto err_create;
 	}
 	size = fdt_totalsize(state->state_fdt);
 	fd = os_open(fname, OS_O_WRONLY | OS_O_CREAT);
 	if (fd < 0) {
 		printf("Cannot open sandbox state file '%s'\n", fname);
 		ret = -EIO;
 		goto err_create;
 	}
 	if (os_write(fd, state->state_fdt, size) != size) {
 		printf("Cannot write sandbox state file '%s'\n", fname);
 		ret = -EIO;
 		goto err_write;
 	}
 	os_close(fd);

 	debug("Wrote sandbox state to '%s'%s\n", fname,
 	      got_err ? " (with errors)" : "");

 	return 0;
 err_write:
 	os_close(fd);
 err_create:
 	os_free(state->state_fdt);

 	return ret;
 }

 int state_setprop(int node, const char *prop_name, const void *data, int size)
 {
 	void *blob;
 	int len;
 	int ret;

 	fdt_getprop(state->state_fdt, node, prop_name, &len);

 	/* Add space for the new property, its name and some overhead */
 	ret = state_ensure_space(size - len + strlen(prop_name) + 32);
 	if (ret)
 		return ret;

 	/* This should succeed, barring a mutiny */
 	blob = state->state_fdt;
 	ret = fdt_setprop(blob, node, prop_name, data, size);
 	if (ret) {
 		printf("%s: Unable to set property '%s' in node '%s': %s\n",
 		       __func__, prop_name, fdt_get_name(blob, node, NULL),
 			fdt_strerror(ret));
 		return -ENOSPC;
 	}

 	return 0;
 }

 struct sandbox_state *state_get_current(void)
 {
 	assert(state);
 	return state;
 }

 void state_set_skip_delays(bool skip_delays)
 {
 	struct sandbox_state *state = state_get_current();

 	state->skip_delays = skip_delays;
 }

 bool state_get_skip_delays(void)
 {
 	struct sandbox_state *state = state_get_current();

 	return state->skip_delays;
 }

 void state_reset_for_test(struct sandbox_state *state)
 {
 	/* No reset yet, so mark it as such. Always allow power reset */
 	state->last_sysreset = SYSRESET_COUNT;
 	state->sysreset_allowed[SYSRESET_POWER_OFF] = true;
 	state->sysreset_allowed[SYSRESET_COLD] = true;
 	state->allow_memio = false;

 	memset(&state->wdt, '\0', sizeof(state->wdt));
 	memset(state->spi, '\0', sizeof(state->spi));

 	/*
 	 * Set up the memory tag list. Use the top of emulated SDRAM for the
 	 * first tag number, since that address offset is outside the legal
 	 * range, and can be assumed to be a tag.
 	 */
 	INIT_LIST_HEAD(&state->mapmem_head);
 	state->next_tag = state->ram_size;
 }

 bool autoboot_keyed(void)
 {
 	struct sandbox_state *state = state_get_current();

 	return IS_ENABLED(CONFIG_AUTOBOOT_KEYED) && state->autoboot_keyed;
 }

 bool autoboot_set_keyed(bool autoboot_keyed)
 {
 	struct sandbox_state *state = state_get_current();
 	bool old_val = state->autoboot_keyed;

 	state->autoboot_keyed = autoboot_keyed;

 	return old_val;
 }

 int state_get_rel_filename(const char *rel_path, char *buf, int size)
 {
 	struct sandbox_state *state = state_get_current();
 	int rel_len, prog_len;
 	char *p;
 	int len;

 	rel_len = strlen(rel_path);
 	p = strrchr(state->argv[0], '/');
 	prog_len = p ? p - state->argv[0] : 0;

 	/* allow space for a / and a terminator */
 	len = prog_len + 1 + rel_len + 1;
 	if (len > size)
 		return -ENOSPC;
 	strncpy(buf, state->argv[0], prog_len);
 	buf[prog_len] = '/';
 	strcpy(buf + prog_len + 1, rel_path);

 	return len;
 }

 int state_load_other_fdt(const char **bufp, int *sizep)
 {
 	struct sandbox_state *state = state_get_current();
 	char fname[256];
 	int len, ret;

 	/* load the file if needed */
 	if (!state->other_fdt_buf) {
 		len = state_get_rel_filename("arch/sandbox/dts/other.dtb",
 					     fname, sizeof(fname));
 		if (len < 0)
 			return len;

 		ret = os_read_file(fname, &state->other_fdt_buf,
 				   &state->other_size);
 		if (ret) {
 			log_err("Cannot read file '%s'\n", fname);
 			return ret;
 		}
 	}
 	*bufp = state->other_fdt_buf;
 	*sizep = state->other_size;

 	return 0;
 }

 int state_init(void)
 {
 	state = &main_state;

 	state->ram_size = CONFIG_SYS_SDRAM_SIZE;
 	state->ram_buf = os_malloc(state->ram_size);
 	if (!state->ram_buf) {
 		printf("Out of memory\n");
 		os_exit(1);
 	}

 	state_reset_for_test(state);
 	/*
 	 * Example of how to use GPIOs:
 	 *
 	 * sandbox_gpio_set_direction(170, 0);
 	 * sandbox_gpio_set_value(170, 0);
 	 */
 	return 0;
 }

 int state_uninit(void)
 {
 	int err;

 	if (state->write_ram_buf || state->write_state)
 		log_debug("Writing sandbox state\n");
 	state = &main_state;

 	/* Finish the bloblist, so that it is correct before writing memory */
 	bloblist_finish();

 	if (state->write_ram_buf) {
 		err = os_write_ram_buf(state->ram_buf_fname);
 		if (err) {
 			printf("Failed to write RAM buffer\n");
 			return err;
 		}
 	}

 	if (state->write_state) {
 		if (sandbox_write_state(state, state->state_fname)) {
 			printf("Failed to write sandbox state\n");
 			return -1;
 		}
 	}

 	/* Delete this at the last moment so as not to upset gdb too much */
 	if (state->jumped_fname)
 		os_unlink(state->jumped_fname);

 	os_free(state->state_fdt);
 	os_free(state->ram_buf);
 	memset(state, '\0', sizeof(*state));

 	return 0;
 }
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* Copyright (c) 2011-2012 The Chromium OS Authors.
	*/

	#include <common.h>
	#include <autoboot.h>
	#include <bloblist.h>
	#include <errno.h>
	#include <fdtdec.h>
	#include <log.h>
	#include <os.h>
	#include <asm/malloc.h>
	#include <asm/state.h>

	/* Main state record for the sandbox */
	static struct sandbox_state main_state;
	static struct sandbox_state state; / Pointer to current state record */

	static int state_ensure_space(int extra_size)
	{
	void *blob = state->state_fdt;
	int used, size, free_bytes;
	void *buf;
	int ret;

	used = fdt_off_dt_strings(blob) + fdt_size_dt_strings(blob);
	size = fdt_totalsize(blob);
	free_bytes = size - used;
	if (free_bytes > extra_size)
	return 0;

	size = used + extra_size;
	buf = os_malloc(size);
	if (!buf)
	return -ENOMEM;

	ret = fdt_open_into(blob, buf, size);
	if (ret) {
	os_free(buf);
	return -EIO;
	}

	os_free(blob);
	state->state_fdt = buf;
	return 0;
	}

	static int state_read_file(struct sandbox_state state, const char fname)
	{
	loff_t size;
	int ret;
	int fd;

	ret = os_get_filesize(fname, &size);
	if (ret < 0) {
	printf("Cannot find sandbox state file '%s'\n", fname);
	return -ENOENT;
	}
	state->state_fdt = os_malloc(size);
	if (!state->state_fdt) {
	puts("No memory to read sandbox state\n");
	return -ENOMEM;
	}
	fd = os_open(fname, OS_O_RDONLY);
	if (fd < 0) {
	printf("Cannot open sandbox state file '%s'\n", fname);
	ret = -EPERM;
	goto err_open;
	}
	if (os_read(fd, state->state_fdt, size) != size) {
	printf("Cannot read sandbox state file '%s'\n", fname);
	ret = -EIO;
	goto err_read;
	}
	os_close(fd);

	return 0;
	err_read:
	os_close(fd);
	err_open:
	/*
	* tainted scalar, since size is obtained from the file. But we can rely
	* on os_malloc() to handle invalid values.
	*/
	os_free(state->state_fdt);
	state->state_fdt = NULL;

	return ret;
	}

	/***
	* sandbox_read_state_nodes() - Read state associated with a driver
	*
	* This looks through all compatible nodes and calls the read function on
	* each one, to read in the state.
	*
	* If nothing is found, it still calls the read function once, to set up a
	* single global state for that driver.
	*
	* @state: Sandbox state
	* @io: Method to use for reading state
	* @blob: FDT containing state
	* Return: 0 if OK, -EINVAL if the read function returned failure
	*/
	int sandbox_read_state_nodes(struct sandbox_state *state,
	struct sandbox_state_io io, const void blob)
	{
	int count;
	int node;
	int ret;

	debug(" - read %s\n", io->name);
	if (!io->read)
	return 0;

	node = -1;
	count = 0;
	while (blob) {
	node = fdt_node_offset_by_compatible(blob, node, io->compat);
	if (node < 0)
	return 0; /* No more */
	debug(" - read node '%s'\n", fdt_get_name(blob, node, NULL));
	ret = io->read(blob, node);
	if (ret) {
	printf("Unable to read state for '%s'\n", io->compat);
	return -EINVAL;
	}
	count++;
	}

	/*
	* If we got no saved state, call the read function once without a
	* node, to set up the global state.
	*/
	if (count == 0) {
	debug(" - read global\n");
	ret = io->read(NULL, -1);
	if (ret) {
	printf("Unable to read global state for '%s'\n",
	io->name);
	return -EINVAL;
	}
	}

	return 0;
	}

	int sandbox_read_state(struct sandbox_state state, const char fname)
	{
	struct sandbox_state_io *io;
	const void *blob;
	bool got_err;
	int ret;

	if (state->read_state && fname) {
	ret = state_read_file(state, fname);
	if (ret == -ENOENT && state->ignore_missing_state_on_read)
	ret = 0;
	if (ret)
	return ret;
	}

	/* Call all the state read functions */
	got_err = false;
	blob = state->state_fdt;
	io = ll_entry_start(struct sandbox_state_io, state_io);
	for (; io < ll_entry_end(struct sandbox_state_io, state_io); io++) {
	ret = sandbox_read_state_nodes(state, io, blob);
	if (ret < 0)
	got_err = true;
	}

	if (state->read_state && fname) {
	debug("Read sandbox state from '%s'%s\n", fname,
	got_err ? " (with errors)" : "");
	}

	return got_err ? -1 : 0;
	}

	/***
	* sandbox_write_state_node() - Write state associated with a driver
	*
	* This calls the write function to write out global state for that driver.
	*
	* TODO(sjg@chromium.org): Support writing out state from multiple drivers
	* of the same time. We don't need this yet,and it will be much easier to
	* do when driver model is available.
	*
	* @state: Sandbox state
	* @io: Method to use for writing state
	* Return: 0 if OK, -EIO if there is a fatal error (such as out of space
	* for adding the data), -EINVAL if the write function failed.
	*/
	int sandbox_write_state_node(struct sandbox_state *state,
	struct sandbox_state_io *io)
	{
	void *blob;
	int node;
	int ret;

	if (!io->write)
	return 0;

	ret = state_ensure_space(SANDBOX_STATE_MIN_SPACE);
	if (ret) {
	printf("Failed to add more space for state\n");
	return -EIO;
	}

	/* The blob location can change when the size increases */
	blob = state->state_fdt;
	node = fdt_node_offset_by_compatible(blob, -1, io->compat);
	if (node == -FDT_ERR_NOTFOUND) {
	node = fdt_add_subnode(blob, 0, io->name);
	if (node < 0) {
	printf("Cannot create node '%s': %s\n", io->name,
	fdt_strerror(node));
	return -EIO;
	}

	if (fdt_setprop_string(blob, node, "compatible", io->compat)) {
	puts("Cannot set compatible\n");
	return -EIO;
	}
	} else if (node < 0) {
	printf("Cannot access node '%s': %s\n", io->name,
	fdt_strerror(node));
	return -EIO;
	}
	debug("Write state for '%s' to node %d\n", io->compat, node);
	ret = io->write(blob, node);
	if (ret) {
	printf("Unable to write state for '%s'\n", io->compat);
	return -EINVAL;
	}

	return 0;
	}

	int sandbox_write_state(struct sandbox_state state, const char fname)
	{
	struct sandbox_state_io *io;
	bool got_err;
	int size;
	int ret;
	int fd;

	/* Create a state FDT if we don't have one */
	if (!state->state_fdt) {
	size = 0x4000;
	state->state_fdt = os_malloc(size);
	if (!state->state_fdt) {
	puts("No memory to create FDT\n");
	return -ENOMEM;
	}
	ret = fdt_create_empty_tree(state->state_fdt, size);
	if (ret < 0) {
	printf("Cannot create empty state FDT: %s\n",
	fdt_strerror(ret));
	ret = -EIO;
	goto err_create;
	}
	}

	/* Call all the state write funtcions */
	got_err = false;
	io = ll_entry_start(struct sandbox_state_io, state_io);
	ret = 0;
	for (; io < ll_entry_end(struct sandbox_state_io, state_io); io++) {
	ret = sandbox_write_state_node(state, io);
	if (ret == -EIO)
	break;
	else if (ret)
	got_err = true;
	}

	if (ret == -EIO) {
	printf("Could not write sandbox state\n");
	goto err_create;
	}

	ret = fdt_pack(state->state_fdt);
	if (ret < 0) {
	printf("Cannot pack state FDT: %s\n", fdt_strerror(ret));
	ret = -EINVAL;
	goto err_create;
	}
	size = fdt_totalsize(state->state_fdt);
	fd = os_open(fname, OS_O_WRONLY \| OS_O_CREAT);
	if (fd < 0) {
	printf("Cannot open sandbox state file '%s'\n", fname);
	ret = -EIO;
	goto err_create;
	}
	if (os_write(fd, state->state_fdt, size) != size) {
	printf("Cannot write sandbox state file '%s'\n", fname);
	ret = -EIO;
	goto err_write;
	}
	os_close(fd);

	debug("Wrote sandbox state to '%s'%s\n", fname,
	got_err ? " (with errors)" : "");

	return 0;
	err_write:
	os_close(fd);
	err_create:
	os_free(state->state_fdt);

	return ret;
	}

	int state_setprop(int node, const char prop_name, const void data, int size)
	{
	void *blob;
	int len;
	int ret;

	fdt_getprop(state->state_fdt, node, prop_name, &len);

	/* Add space for the new property, its name and some overhead */
	ret = state_ensure_space(size - len + strlen(prop_name) + 32);
	if (ret)
	return ret;

	/* This should succeed, barring a mutiny */
	blob = state->state_fdt;
	ret = fdt_setprop(blob, node, prop_name, data, size);
	if (ret) {
	printf("%s: Unable to set property '%s' in node '%s': %s\n",
	__func__, prop_name, fdt_get_name(blob, node, NULL),
	fdt_strerror(ret));
	return -ENOSPC;
	}

	return 0;
	}

	struct sandbox_state *state_get_current(void)
	{
	assert(state);
	return state;
	}

	void state_set_skip_delays(bool skip_delays)
	{
	struct sandbox_state *state = state_get_current();

	state->skip_delays = skip_delays;
	}

	bool state_get_skip_delays(void)
	{
	struct sandbox_state *state = state_get_current();

	return state->skip_delays;
	}

	void state_reset_for_test(struct sandbox_state *state)
	{
	/* No reset yet, so mark it as such. Always allow power reset */
	state->last_sysreset = SYSRESET_COUNT;
	state->sysreset_allowed[SYSRESET_POWER_OFF] = true;
	state->sysreset_allowed[SYSRESET_COLD] = true;
	state->allow_memio = false;

	memset(&state->wdt, '\0', sizeof(state->wdt));
	memset(state->spi, '\0', sizeof(state->spi));

	/*
	* Set up the memory tag list. Use the top of emulated SDRAM for the
	* first tag number, since that address offset is outside the legal
	* range, and can be assumed to be a tag.
	*/
	INIT_LIST_HEAD(&state->mapmem_head);
	state->next_tag = state->ram_size;
	}

	bool autoboot_keyed(void)
	{
	struct sandbox_state *state = state_get_current();

	return IS_ENABLED(CONFIG_AUTOBOOT_KEYED) && state->autoboot_keyed;
	}

	bool autoboot_set_keyed(bool autoboot_keyed)
	{
	struct sandbox_state *state = state_get_current();
	bool old_val = state->autoboot_keyed;

	state->autoboot_keyed = autoboot_keyed;

	return old_val;
	}

	int state_get_rel_filename(const char rel_path, char buf, int size)
	{
	struct sandbox_state *state = state_get_current();
	int rel_len, prog_len;
	char *p;
	int len;

	rel_len = strlen(rel_path);
	p = strrchr(state->argv[0], '/');
	prog_len = p ? p - state->argv[0] : 0;

	/* allow space for a / and a terminator */
	len = prog_len + 1 + rel_len + 1;
	if (len > size)
	return -ENOSPC;
	strncpy(buf, state->argv[0], prog_len);
	buf[prog_len] = '/';
	strcpy(buf + prog_len + 1, rel_path);

	return len;
	}

	int state_load_other_fdt(const char *bufp, int sizep)
	{
	struct sandbox_state *state = state_get_current();
	char fname[256];
	int len, ret;

	/* load the file if needed */
	if (!state->other_fdt_buf) {
	len = state_get_rel_filename("arch/sandbox/dts/other.dtb",
	fname, sizeof(fname));
	if (len < 0)
	return len;

	ret = os_read_file(fname, &state->other_fdt_buf,
	&state->other_size);
	if (ret) {
	log_err("Cannot read file '%s'\n", fname);
	return ret;
	}
	}
	*bufp = state->other_fdt_buf;
	*sizep = state->other_size;

	return 0;
	}

	int state_init(void)
	{
	state = &main_state;

	state->ram_size = CONFIG_SYS_SDRAM_SIZE;
	state->ram_buf = os_malloc(state->ram_size);
	if (!state->ram_buf) {
	printf("Out of memory\n");
	os_exit(1);
	}

	state_reset_for_test(state);
	/*
	* Example of how to use GPIOs:
	*
	* sandbox_gpio_set_direction(170, 0);
	* sandbox_gpio_set_value(170, 0);
	*/
	return 0;
	}

	int state_uninit(void)
	{
	int err;

	if (state->write_ram_buf \|\| state->write_state)
	log_debug("Writing sandbox state\n");
	state = &main_state;

	/* Finish the bloblist, so that it is correct before writing memory */
	bloblist_finish();

	if (state->write_ram_buf) {
	err = os_write_ram_buf(state->ram_buf_fname);
	if (err) {
	printf("Failed to write RAM buffer\n");
	return err;
	}
	}

	if (state->write_state) {
	if (sandbox_write_state(state, state->state_fname)) {
	printf("Failed to write sandbox state\n");
	return -1;
	}
	}

	/* Delete this at the last moment so as not to upset gdb too much */
	if (state->jumped_fname)
	os_unlink(state->jumped_fname);

	os_free(state->state_fdt);
	os_free(state->ram_buf);
	memset(state, '\0', sizeof(*state));

	return 0;
	}