diff options
Diffstat (limited to 'lib/fdtdec.c')
| -rw-r--r-- | lib/fdtdec.c | 323 | 
1 files changed, 313 insertions, 10 deletions
| diff --git a/lib/fdtdec.c b/lib/fdtdec.c index 0f871638c..bdec1a0d9 100644 --- a/lib/fdtdec.c +++ b/lib/fdtdec.c @@ -24,6 +24,9 @@  #include <libfdt.h>  #include <fdtdec.h> +/* we need the generic GPIO interface here */ +#include <asm-generic/gpio.h> +  DECLARE_GLOBAL_DATA_PTR;  /* @@ -33,8 +36,19 @@ DECLARE_GLOBAL_DATA_PTR;   */  #define COMPAT(id, name) name  static const char * const compat_names[COMPAT_COUNT] = { +	COMPAT(UNKNOWN, "<none>"), +	COMPAT(NVIDIA_TEGRA20_USB, "nvidia,tegra20-ehci"), +	COMPAT(NVIDIA_TEGRA20_I2C, "nvidia,tegra20-i2c"), +	COMPAT(NVIDIA_TEGRA20_DVC, "nvidia,tegra20-i2c-dvc"),  }; +const char *fdtdec_get_compatible(enum fdt_compat_id id) +{ +	/* We allow reading of the 'unknown' ID for testing purposes */ +	assert(id >= 0 && id < COMPAT_COUNT); +	return compat_names[id]; +} +  /**   * Look in the FDT for an alias with the given name and return its node.   * @@ -84,14 +98,21 @@ s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,  	return default_val;  } -int fdtdec_get_is_enabled(const void *blob, int node, int default_val) +int fdtdec_get_is_enabled(const void *blob, int node)  {  	const char *cell; +	/* +	 * It should say "okay", so only allow that. Some fdts use "ok" but +	 * this is a bug. Please fix your device tree source file. See here +	 * for discussion: +	 * +	 * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html +	 */  	cell = fdt_getprop(blob, node, "status", NULL);  	if (cell) -		return 0 == strcmp(cell, "ok"); -	return default_val; +		return 0 == strcmp(cell, "okay"); +	return 1;  }  enum fdt_compat_id fd_dec_lookup(const void *blob, int node) @@ -122,14 +143,151 @@ int fdtdec_next_alias(const void *blob, const char *name,  	/* snprintf() is not available */  	assert(strlen(name) < MAX_STR_LEN);  	sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto); -	(*upto)++;  	node = find_alias_node(blob, str);  	if (node < 0)  		return node;  	err = fdt_node_check_compatible(blob, node, compat_names[id]);  	if (err < 0)  		return err; -	return err ? -FDT_ERR_NOTFOUND : node; +	if (err) +		return -FDT_ERR_NOTFOUND; +	(*upto)++; +	return node; +} + +int fdtdec_find_aliases_for_id(const void *blob, const char *name, +			enum fdt_compat_id id, int *node_list, int maxcount) +{ +	memset(node_list, '\0', sizeof(*node_list) * maxcount); + +	return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount); +} + +/* TODO: Can we tighten this code up a little? */ +int fdtdec_add_aliases_for_id(const void *blob, const char *name, +			enum fdt_compat_id id, int *node_list, int maxcount) +{ +	int name_len = strlen(name); +	int nodes[maxcount]; +	int num_found = 0; +	int offset, node; +	int alias_node; +	int count; +	int i, j; + +	/* find the alias node if present */ +	alias_node = fdt_path_offset(blob, "/aliases"); + +	/* +	 * start with nothing, and we can assume that the root node can't +	 * match +	 */ +	memset(nodes, '\0', sizeof(nodes)); + +	/* First find all the compatible nodes */ +	for (node = count = 0; node >= 0 && count < maxcount;) { +		node = fdtdec_next_compatible(blob, node, id); +		if (node >= 0) +			nodes[count++] = node; +	} +	if (node >= 0) +		debug("%s: warning: maxcount exceeded with alias '%s'\n", +		       __func__, name); + +	/* Now find all the aliases */ +	for (offset = fdt_first_property_offset(blob, alias_node); +			offset > 0; +			offset = fdt_next_property_offset(blob, offset)) { +		const struct fdt_property *prop; +		const char *path; +		int number; +		int found; + +		node = 0; +		prop = fdt_get_property_by_offset(blob, offset, NULL); +		path = fdt_string(blob, fdt32_to_cpu(prop->nameoff)); +		if (prop->len && 0 == strncmp(path, name, name_len)) +			node = fdt_path_offset(blob, prop->data); +		if (node <= 0) +			continue; + +		/* Get the alias number */ +		number = simple_strtoul(path + name_len, NULL, 10); +		if (number < 0 || number >= maxcount) { +			debug("%s: warning: alias '%s' is out of range\n", +			       __func__, path); +			continue; +		} + +		/* Make sure the node we found is actually in our list! */ +		found = -1; +		for (j = 0; j < count; j++) +			if (nodes[j] == node) { +				found = j; +				break; +			} + +		if (found == -1) { +			debug("%s: warning: alias '%s' points to a node " +				"'%s' that is missing or is not compatible " +				" with '%s'\n", __func__, path, +				fdt_get_name(blob, node, NULL), +			       compat_names[id]); +			continue; +		} + +		/* +		 * Add this node to our list in the right place, and mark +		 * it as done. +		 */ +		if (fdtdec_get_is_enabled(blob, node)) { +			if (node_list[number]) { +				debug("%s: warning: alias '%s' requires that " +				      "a node be placed in the list in a " +				      "position which is already filled by " +				      "node '%s'\n", __func__, path, +				      fdt_get_name(blob, node, NULL)); +				continue; +			} +			node_list[number] = node; +			if (number >= num_found) +				num_found = number + 1; +		} +		nodes[found] = 0; +	} + +	/* Add any nodes not mentioned by an alias */ +	for (i = j = 0; i < maxcount; i++) { +		if (!node_list[i]) { +			for (; j < maxcount; j++) +				if (nodes[j] && +					fdtdec_get_is_enabled(blob, nodes[j])) +					break; + +			/* Have we run out of nodes to add? */ +			if (j == maxcount) +				break; + +			assert(!node_list[i]); +			node_list[i] = nodes[j++]; +			if (i >= num_found) +				num_found = i + 1; +		} +	} + +	return num_found; +} + +int fdtdec_check_fdt(void) +{ +	/* +	 * We must have an FDT, but we cannot panic() yet since the console +	 * is not ready. So for now, just assert(). Boards which need an early +	 * FDT (prior to console ready) will need to make their own +	 * arrangements and do their own checks. +	 */ +	assert(!fdtdec_prepare_fdt()); +	return 0;  }  /* @@ -137,11 +295,156 @@ int fdtdec_next_alias(const void *blob, const char *name,   * point if the architecture board.c files merge this will make more sense.   * Even now, it is common code.   */ -int fdtdec_check_fdt(void) +int fdtdec_prepare_fdt(void) +{ +	if (((uintptr_t)gd->fdt_blob & 3) || fdt_check_header(gd->fdt_blob)) { +		printf("No valid FDT found - please append one to U-Boot " +			"binary, use u-boot-dtb.bin or define " +			"CONFIG_OF_EMBED\n"); +		return -1; +	} +	return 0; +} + +int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name) +{ +	const u32 *phandle; +	int lookup; + +	phandle = fdt_getprop(blob, node, prop_name, NULL); +	if (!phandle) +		return -FDT_ERR_NOTFOUND; + +	lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle)); +	return lookup; +} + +/** + * Look up a property in a node and check that it has a minimum length. + * + * @param blob		FDT blob + * @param node		node to examine + * @param prop_name	name of property to find + * @param min_len	minimum property length in bytes + * @param err		0 if ok, or -FDT_ERR_NOTFOUND if the property is not +			found, or -FDT_ERR_BADLAYOUT if not enough data + * @return pointer to cell, which is only valid if err == 0 + */ +static const void *get_prop_check_min_len(const void *blob, int node, +		const char *prop_name, int min_len, int *err)  { -	/* We must have an fdt */ -	if (fdt_check_header(gd->fdt_blob)) -		panic("No valid fdt found - please append one to U-Boot\n" -			"binary or define CONFIG_OF_EMBED\n"); +	const void *cell; +	int len; + +	debug("%s: %s\n", __func__, prop_name); +	cell = fdt_getprop(blob, node, prop_name, &len); +	if (!cell) +		*err = -FDT_ERR_NOTFOUND; +	else if (len < min_len) +		*err = -FDT_ERR_BADLAYOUT; +	else +		*err = 0; +	return cell; +} + +int fdtdec_get_int_array(const void *blob, int node, const char *prop_name, +		u32 *array, int count) +{ +	const u32 *cell; +	int i, err = 0; + +	debug("%s: %s\n", __func__, prop_name); +	cell = get_prop_check_min_len(blob, node, prop_name, +				      sizeof(u32) * count, &err); +	if (!err) { +		for (i = 0; i < count; i++) +			array[i] = fdt32_to_cpu(cell[i]); +	} +	return err; +} + +int fdtdec_get_bool(const void *blob, int node, const char *prop_name) +{ +	const s32 *cell; +	int len; + +	debug("%s: %s\n", __func__, prop_name); +	cell = fdt_getprop(blob, node, prop_name, &len); +	return cell != NULL; +} + +/** + * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no + * terminating item. + * + * @param blob		FDT blob to use + * @param node		Node to look at + * @param prop_name	Node property name + * @param gpio		Array of gpio elements to fill from FDT. This will be + *			untouched if either 0 or an error is returned + * @param max_count	Maximum number of elements allowed + * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would + * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing. + */ +static int fdtdec_decode_gpios(const void *blob, int node, +		const char *prop_name, struct fdt_gpio_state *gpio, +		int max_count) +{ +	const struct fdt_property *prop; +	const u32 *cell; +	const char *name; +	int len, i; + +	debug("%s: %s\n", __func__, prop_name); +	assert(max_count > 0); +	prop = fdt_get_property(blob, node, prop_name, &len); +	if (!prop) { +		debug("FDT: %s: property '%s' missing\n", __func__, prop_name); +		return -FDT_ERR_NOTFOUND; +	} + +	/* We will use the name to tag the GPIO */ +	name = fdt_string(blob, fdt32_to_cpu(prop->nameoff)); +	cell = (u32 *)prop->data; +	len /= sizeof(u32) * 3;		/* 3 cells per GPIO record */ +	if (len > max_count) { +		debug("FDT: %s: too many GPIOs / cells for " +			"property '%s'\n", __func__, prop_name); +		return -FDT_ERR_BADLAYOUT; +	} + +	/* Read out the GPIO data from the cells */ +	for (i = 0; i < len; i++, cell += 3) { +		gpio[i].gpio = fdt32_to_cpu(cell[1]); +		gpio[i].flags = fdt32_to_cpu(cell[2]); +		gpio[i].name = name; +	} + +	return len; +} + +int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name, +		struct fdt_gpio_state *gpio) +{ +	int err; + +	debug("%s: %s\n", __func__, prop_name); +	gpio->gpio = FDT_GPIO_NONE; +	gpio->name = NULL; +	err = fdtdec_decode_gpios(blob, node, prop_name, gpio, 1); +	return err == 1 ? 0 : err; +} + +int fdtdec_setup_gpio(struct fdt_gpio_state *gpio) +{ +	/* +	 * Return success if there is no GPIO defined. This is used for +	 * optional GPIOs) +	 */ +	if (!fdt_gpio_isvalid(gpio)) +		return 0; + +	if (gpio_request(gpio->gpio, gpio->name)) +		return -1;  	return 0;  } |