Commit 6d79566a authored by Eric Auger's avatar Eric Auger Committed by Alex Williamson
Browse files

device_tree: introduce qemu_fdt_node_path 



This new helper routine returns a NULL terminated array of
node paths matching a node name and a compat string.

Signed-off-by: default avatarEric Auger <eric.auger@linaro.org>
Reviewed-by: default avatarPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: default avatarAlex Williamson <alex.williamson@redhat.com>
parent 60e43e98

device_tree.c

+54 −0
Original line number Diff line number Diff line
@@ -226,6 +226,60 @@ static int findnode_nofail(void *fdt, const char *node_path) 
    return offset;

}



char **qemu_fdt_node_path(void *fdt, const char *name, char *compat,

                          Error **errp)

{

    int offset, len, ret;

    const char *iter_name;

    unsigned int path_len = 16, n = 0;

    GSList *path_list = NULL, *iter;

    char **path_array;



    offset = fdt_node_offset_by_compatible(fdt, -1, compat);



    while (offset >= 0) {

        iter_name = fdt_get_name(fdt, offset, &len);

        if (!iter_name) {

            offset = len;

            break;

        }

        if (!strcmp(iter_name, name)) {

            char *path;



            path = g_malloc(path_len);

            while ((ret = fdt_get_path(fdt, offset, path, path_len))

                  == -FDT_ERR_NOSPACE) {

                path_len += 16;

                path = g_realloc(path, path_len);

            }

            path_list = g_slist_prepend(path_list, path);

            n++;

        }

        offset = fdt_node_offset_by_compatible(fdt, offset, compat);

    }



    if (offset < 0 && offset != -FDT_ERR_NOTFOUND) {

        error_setg(errp, "%s: abort parsing dt for %s/%s: %s",

                   __func__, name, compat, fdt_strerror(offset));

        for (iter = path_list; iter; iter = iter->next) {

            g_free(iter->data);

        }

        g_slist_free(path_list);

        return NULL;

    }



    path_array = g_new(char *, n + 1);

    path_array[n--] = NULL;



    for (iter = path_list; iter; iter = iter->next) {

        path_array[n--] = iter->data;

    }



    g_slist_free(path_list);



    return path_array;

}



int qemu_fdt_setprop(void *fdt, const char *node_path,

                     const char *property, const void *val, int size)

{

include/sysemu/device_tree.h

+18 −0
Original line number Diff line number Diff line
@@ -25,6 +25,24 @@ void *load_device_tree(const char *filename_path, int *sizep); 
void *load_device_tree_from_sysfs(void);

#endif



/**

 * qemu_fdt_node_path: return the paths of nodes matching a given

 * name and compat string

 * @fdt: pointer to the dt blob

 * @name: node name

 * @compat: compatibility string

 * @errp: handle to an error object

 *

 * returns a newly allocated NULL-terminated array of node paths.

 * Use g_strfreev() to free it. If one or more nodes were found, the

 * array contains the path of each node and the last element equals to

 * NULL. If there is no error but no matching node was found, the

 * returned array contains a single element equal to NULL. If an error

 * was encountered when parsing the blob, the function returns NULL

 */

char **qemu_fdt_node_path(void *fdt, const char *name, char *compat,

                          Error **errp);



int qemu_fdt_setprop(void *fdt, const char *node_path,

                     const char *property, const void *val, int size);

int qemu_fdt_setprop_cell(void *fdt, const char *node_path,