From c8cb7a59842c0b512b44f6f818cdb0b5a3ddc89e Mon Sep 17 00:00:00 2001 From: Grant Likely Date: Mon, 23 Nov 2009 18:54:23 -0700 Subject: of/flattree: merge of_scan_flat_dt Merge common code between PowerPC and Microblaze Signed-off-by: Grant Likely Reviewed-by: Wolfram Sang Tested-by: Michal Simek --- drivers/of/fdt.c | 64 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 64 insertions(+) (limited to 'drivers/of/fdt.c') diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index 9faa9a5cbdf..dd9057cb7aa 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -19,3 +19,67 @@ char *find_flat_dt_string(u32 offset) return ((char *)initial_boot_params) + initial_boot_params->off_dt_strings + offset; } + +/** + * of_scan_flat_dt - scan flattened tree blob and call callback on each. + * @it: callback function + * @data: context data pointer + * + * This function is used to scan the flattened device-tree, it is + * used to extract the memory information at boot before we can + * unflatten the tree + */ +int __init of_scan_flat_dt(int (*it)(unsigned long node, + const char *uname, int depth, + void *data), + void *data) +{ + unsigned long p = ((unsigned long)initial_boot_params) + + initial_boot_params->off_dt_struct; + int rc = 0; + int depth = -1; + + do { + u32 tag = *((u32 *)p); + char *pathp; + + p += 4; + if (tag == OF_DT_END_NODE) { + depth--; + continue; + } + if (tag == OF_DT_NOP) + continue; + if (tag == OF_DT_END) + break; + if (tag == OF_DT_PROP) { + u32 sz = *((u32 *)p); + p += 8; + if (initial_boot_params->version < 0x10) + p = _ALIGN(p, sz >= 8 ? 8 : 4); + p += sz; + p = _ALIGN(p, 4); + continue; + } + if (tag != OF_DT_BEGIN_NODE) { + pr_err("Invalid tag %x in flat device tree!\n", tag); + return -EINVAL; + } + depth++; + pathp = (char *)p; + p = _ALIGN(p + strlen(pathp) + 1, 4); + if ((*pathp) == '/') { + char *lp, *np; + for (lp = NULL, np = pathp; *np; np++) + if ((*np) == '/') + lp = np+1; + if (lp != NULL) + pathp = lp; + } + rc = it(p, pathp, depth, data); + if (rc != 0) + break; + } while (1); + + return rc; +} -- cgit v1.2.3