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Diffstat (limited to '')
-rw-r--r-- | arch/powerpc/platforms/pseries/of_helpers.c | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pseries/of_helpers.c b/arch/powerpc/platforms/pseries/of_helpers.c new file mode 100644 index 000000000..23241c71e --- /dev/null +++ b/arch/powerpc/platforms/pseries/of_helpers.c @@ -0,0 +1,97 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/string.h> +#include <linux/err.h> +#include <linux/slab.h> +#include <linux/of.h> +#include <asm/prom.h> + +#include "of_helpers.h" + +/** + * pseries_of_derive_parent - basically like dirname(1) + * @path: the full_name of a node to be added to the tree + * + * Returns the node which should be the parent of the node + * described by path. E.g., for path = "/foo/bar", returns + * the node with full_name = "/foo". + */ +struct device_node *pseries_of_derive_parent(const char *path) +{ + struct device_node *parent; + char *parent_path = "/"; + const char *tail; + + /* We do not want the trailing '/' character */ + tail = kbasename(path) - 1; + + /* reject if path is "/" */ + if (!strcmp(path, "/")) + return ERR_PTR(-EINVAL); + + if (tail > path) { + parent_path = kstrndup(path, tail - path, GFP_KERNEL); + if (!parent_path) + return ERR_PTR(-ENOMEM); + } + parent = of_find_node_by_path(parent_path); + if (strcmp(parent_path, "/")) + kfree(parent_path); + return parent ? parent : ERR_PTR(-EINVAL); +} + + +/* Helper Routines to convert between drc_index to cpu numbers */ + +int of_read_drc_info_cell(struct property **prop, const __be32 **curval, + struct of_drc_info *data) +{ + const char *p = (char *)(*curval); + const __be32 *p2; + + if (!data) + return -EINVAL; + + /* Get drc-type:encode-string */ + data->drc_type = (char *)p; + p = of_prop_next_string(*prop, p); + if (!p) + return -EINVAL; + + /* Get drc-name-prefix:encode-string */ + data->drc_name_prefix = (char *)p; + p = of_prop_next_string(*prop, p); + if (!p) + return -EINVAL; + + /* Get drc-index-start:encode-int */ + p2 = (const __be32 *)p; + data->drc_index_start = be32_to_cpu(*p2); + + /* Get drc-name-suffix-start:encode-int */ + p2 = of_prop_next_u32(*prop, p2, &data->drc_name_suffix_start); + if (!p2) + return -EINVAL; + + /* Get number-sequential-elements:encode-int */ + p2 = of_prop_next_u32(*prop, p2, &data->num_sequential_elems); + if (!p2) + return -EINVAL; + + /* Get sequential-increment:encode-int */ + p2 = of_prop_next_u32(*prop, p2, &data->sequential_inc); + if (!p2) + return -EINVAL; + + /* Get drc-power-domain:encode-int */ + p2 = of_prop_next_u32(*prop, p2, &data->drc_power_domain); + if (!p2) + return -EINVAL; + + /* Should now know end of current entry */ + (*curval) = (void *)(++p2); + data->last_drc_index = data->drc_index_start + + ((data->num_sequential_elems - 1) * data->sequential_inc); + + return 0; +} +EXPORT_SYMBOL(of_read_drc_info_cell); |