• Antonio Nino Diaz's avatar
    Sanitise includes across codebase · 09d40e0e
    Antonio Nino Diaz authored
    Enforce full include path for includes. Deprecate old paths.
    
    The following folders inside include/lib have been left unchanged:
    
    - include/lib/cpus/${ARCH}
    - include/lib/el3_runtime/${ARCH}
    
    The reason for this change is that having a global namespace for
    includes isn't a good idea. It defeats one of the advantages of having
    folders and it introduces problems that are sometimes subtle (because
    you may not know the header you are actually including if there are two
    of them).
    
    For example, this patch had to be created because two headers were
    called the same way: e0ea0928 ("Fix gpio includes of mt8173 platform
    to avoid collision."). More recently, this patch has had similar
    problems: 46f9b2c3 ("drivers: add tzc380 support").
    
    This problem was introduced in commit 4ecca339 ("Move include and
    source files to logical locations"). At that time, there weren't too
    many headers so it wasn't a real issue. However, time has shown that
    this creates problems.
    
    Platforms t...
    09d40e0e
fdt_wrappers.c 3.84 KB
/*
 * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

/* Helper functions to offer easier navigation of Device Tree Blob */

#include <assert.h>
#include <string.h>

#include <libfdt.h>

#include <common/debug.h>
#include <common/fdt_wrappers.h>

/*
 * Read cells from a given property of the given node. At most 2 cells of the
 * property are read, and pointer is updated. Returns 0 on success, and -1 upon
 * error
 */
int fdtw_read_cells(const void *dtb, int node, const char *prop,
		unsigned int cells, void *value)
{
	const uint32_t *value_ptr;
	uint32_t hi = 0, lo;
	int value_len;

	assert(dtb != NULL);
	assert(prop != NULL);
	assert(value != NULL);
	assert(node >= 0);

	/* We expect either 1 or 2 cell property */
	assert(cells <= 2U);

	/* Access property and obtain its length (in bytes) */
	value_ptr = fdt_getprop_namelen(dtb, node, prop, (int)strlen(prop),
			&value_len);
	if (value_ptr == NULL) {
		WARN("Couldn't find property %s in dtb\n", prop);
		return -1;
	}

	/* Verify that property length accords with cell length */
	if (NCELLS((unsigned int)value_len) != cells) {
		WARN("Property length mismatch\n");
		return -1;
	}

	if (cells == 2U) {
		hi = fdt32_to_cpu(*value_ptr);
		value_ptr++;
	}

	lo = fdt32_to_cpu(*value_ptr);

	if (cells == 2U)
		*((uint64_t *) value) = ((uint64_t) hi << 32) | lo;
	else
		*((uint32_t *) value) = lo;

	return 0;
}

/*
 * Read cells from a given property of the given node. Any number of 32-bit
 * cells of the property can be read. The fdt pointer is updated. Returns 0 on
 * success, and -1 on error.
 */
int fdtw_read_array(const void *dtb, int node, const char *prop,
		unsigned int cells, void *value)
{
	const uint32_t *value_ptr;
	int value_len;

	assert(dtb != NULL);
	assert(prop != NULL);
	assert(value != NULL);
	assert(node >= 0);

	/* Access property and obtain its length (in bytes) */
	value_ptr = fdt_getprop_namelen(dtb, node, prop, (int)strlen(prop),
			&value_len);
	if (value_ptr == NULL) {
		WARN("Couldn't find property %s in dtb\n", prop);
		return -1;
	}

	/* Verify that property length accords with cell length */
	if (NCELLS((unsigned int)value_len) != cells) {
		WARN("Property length mismatch\n");
		return -1;
	}

	uint32_t *dst = value;

	for (unsigned int i = 0U; i < cells; i++) {
		dst[i] = fdt32_to_cpu(value_ptr[i]);
	}

	return 0;
}

/*
 * Read string from a given property of the given node. Up to 'size - 1'
 * characters are read, and a NUL terminator is added. Returns 0 on success,
 * and -1 upon error.
 */
int fdtw_read_string(const void *dtb, int node, const char *prop,
		char *str, size_t size)
{
	const char *ptr;
	size_t len;

	assert(dtb != NULL);
	assert(node >= 0);
	assert(prop != NULL);
	assert(str != NULL);
	assert(size > 0U);

	ptr = fdt_getprop_namelen(dtb, node, prop, (int)strlen(prop), NULL);
	if (ptr == NULL) {
		WARN("Couldn't find property %s in dtb\n", prop);
		return -1;
	}

	len = strlcpy(str, ptr, size);
	if (len >= size) {
		WARN("String of property %s in dtb has been truncated\n", prop);
		return -1;
	}

	return 0;
}

/*
 * Write cells in place to a given property of the given node. At most 2 cells
 * of the property are written. Returns 0 on success, and -1 upon error.
 */
int fdtw_write_inplace_cells(void *dtb, int node, const char *prop,
		unsigned int cells, void *value)
{
	int err, len;

	assert(dtb != NULL);
	assert(prop != NULL);
	assert(value != NULL);
	assert(node >= 0);

	/* We expect either 1 or 2 cell property */
	assert(cells <= 2U);

	if (cells == 2U)
		*(uint64_t *)value = cpu_to_fdt64(*(uint64_t *)value);
	else
		*(uint32_t *)value = cpu_to_fdt32(*(uint32_t *)value);

	len = (int)cells * 4;

	/* Set property value in place */
	err = fdt_setprop_inplace(dtb, node, prop, value, len);
	if (err != 0) {
		WARN("Modify property %s failed with error %d\n", prop, err);
		return -1;
	}

	return 0;
}