100 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			100 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
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| #include <linux/string.h>
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| #include <linux/err.h>
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| #include <linux/slab.h>
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| #include <linux/of.h>
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| #include <asm/prom.h>
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| 
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| #include "of_helpers.h"
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| 
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| /**
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|  * pseries_of_derive_parent - basically like dirname(1)
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|  * @path:  the full_name of a node to be added to the tree
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|  *
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|  * Returns the node which should be the parent of the node
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|  * described by path.  E.g., for path = "/foo/bar", returns
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|  * the node with full_name = "/foo".
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|  */
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| struct device_node *pseries_of_derive_parent(const char *path)
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| {
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| 	struct device_node *parent;
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| 	char *parent_path = "/";
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| 	const char *tail;
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| 
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| 	/* We do not want the trailing '/' character */
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| 	tail = kbasename(path) - 1;
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| 
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| 	/* reject if path is "/" */
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| 	if (!strcmp(path, "/"))
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| 		return ERR_PTR(-EINVAL);
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| 
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| 	if (tail > path) {
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| 		parent_path = kstrndup(path, tail - path, GFP_KERNEL);
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| 		if (!parent_path)
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| 			return ERR_PTR(-ENOMEM);
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| 	}
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| 	parent = of_find_node_by_path(parent_path);
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| 	if (strcmp(parent_path, "/"))
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| 		kfree(parent_path);
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| 	return parent ? parent : ERR_PTR(-EINVAL);
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| }
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| 
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| 
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| /* Helper Routines to convert between drc_index to cpu numbers */
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| 
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| int of_read_drc_info_cell(struct property **prop, const __be32 **curval,
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| 			struct of_drc_info *data)
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| {
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| 	const char *p;
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| 	const __be32 *p2;
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| 
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| 	if (!data)
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| 		return -EINVAL;
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| 
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| 	/* Get drc-type:encode-string */
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| 	p = data->drc_type = (char*) (*curval);
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| 	p = of_prop_next_string(*prop, p);
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| 	if (!p)
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| 		return -EINVAL;
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| 
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| 	/* Get drc-name-prefix:encode-string */
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| 	data->drc_name_prefix = (char *)p;
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| 	p = of_prop_next_string(*prop, p);
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| 	if (!p)
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| 		return -EINVAL;
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| 
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| 	/* Get drc-index-start:encode-int */
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| 	p2 = (const __be32 *)p;
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| 	p2 = of_prop_next_u32(*prop, p2, &data->drc_index_start);
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| 	if (!p2)
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| 		return -EINVAL;
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| 
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| 	/* Get drc-name-suffix-start:encode-int */
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| 	p2 = of_prop_next_u32(*prop, p2, &data->drc_name_suffix_start);
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| 	if (!p2)
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| 		return -EINVAL;
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| 
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| 	/* Get number-sequential-elements:encode-int */
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| 	p2 = of_prop_next_u32(*prop, p2, &data->num_sequential_elems);
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| 	if (!p2)
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| 		return -EINVAL;
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| 
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| 	/* Get sequential-increment:encode-int */
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| 	p2 = of_prop_next_u32(*prop, p2, &data->sequential_inc);
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| 	if (!p2)
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| 		return -EINVAL;
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| 
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| 	/* Get drc-power-domain:encode-int */
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| 	p2 = of_prop_next_u32(*prop, p2, &data->drc_power_domain);
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| 	if (!p2)
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| 		return -EINVAL;
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| 
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| 	/* Should now know end of current entry */
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| 	(*curval) = (void *)p2;
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| 	data->last_drc_index = data->drc_index_start +
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| 		((data->num_sequential_elems - 1) * data->sequential_inc);
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| 
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| 	return 0;
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| }
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| EXPORT_SYMBOL(of_read_drc_info_cell);
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