[PATCH 7/7] libfdt: Allow control of version checks

[Simon Glass <sjg@xxxxxxxxxxxx>]

At present libfdt includes checks on the version of the device tree. These
checks are unnecessary if a known device tree version is used. Allow these
checks to be disabled to reduce code size.

Signed-off-by: Simon Glass <sjg@xxxxxxxxxxxx>
---

 libfdt/fdt.c    | 12 +++++++-----
 libfdt/fdt_ro.c | 14 +++++++-------
 libfdt/fdt_rw.c |  4 ++--
 libfdt/libfdt.h |  2 +-
 4 files changed, 17 insertions(+), 15 deletions(-)

diff --git a/libfdt/fdt.c b/libfdt/fdt.c
index fea49cb..6ca5d12 100644
--- a/libfdt/fdt.c
+++ b/libfdt/fdt.c
@@ -122,11 +122,12 @@ const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int len)
 		    || ((absoffset + len) < absoffset)
 		    || (absoffset + len) > fdt_totalsize(fdt))
 			return NULL;
+
+		if (_check1() && fdt_version(fdt) >= 0x11)
+			if (((offset + len) < offset)
+			    || ((offset + len) > fdt_size_dt_struct(fdt)))
+				return NULL;
 	}
-	if (fdt_version(fdt) >= 0x11)
-		if (((offset + len) < offset)
-		    || ((offset + len) > fdt_size_dt_struct(fdt)))
-			return NULL;
 
 	return fdt_offset_ptr_(fdt, offset);
 }
@@ -163,7 +164,8 @@ uint32_t fdt_next_tag(const void *fdt, int startoffset, int *nextoffset)
 		/* skip-name offset, length and value */
 		offset += sizeof(struct fdt_property) - FDT_TAGSIZE
 			+ fdt32_to_cpu(*lenp);
-		if (fdt_version(fdt) < 0x10 && fdt32_to_cpu(*lenp) >= 8 &&
+		if (_check1() &&
+		    fdt_version(fdt) < 0x10 && fdt32_to_cpu(*lenp) >= 8 &&
 		    ((offset - fdt32_to_cpu(*lenp)) % 8) != 0)
 			offset += 4;
 		break;
diff --git a/libfdt/fdt_ro.c b/libfdt/fdt_ro.c
index bc1b4e0..82d02d3 100644
--- a/libfdt/fdt_ro.c
+++ b/libfdt/fdt_ro.c
@@ -57,7 +57,7 @@ const char *fdt_get_string(const void *fdt, int stroffset, int *lenp)
 	if (fdt_magic(fdt) == FDT_MAGIC) {
 		if (stroffset < 0)
 			goto fail;
-		if (fdt_version(fdt) >= 17) {
+		if (_check1() && fdt_version(fdt) >= 17) {
 			if (stroffset >= fdt_size_dt_strings(fdt))
 				goto fail;
 			if ((fdt_size_dt_strings(fdt) - stroffset) < len)
@@ -377,7 +377,7 @@ const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
 	/* Prior to version 16, properties may need realignment
 	 * and this API does not work. fdt_getprop_*() will, however. */
 
-	if (fdt_version(fdt) < 0x10) {
+	if (_check1() && fdt_version(fdt) < 0x10) {
 		if (lenp)
 			*lenp = -FDT_ERR_BADVERSION;
 		return NULL;
@@ -424,7 +424,7 @@ const struct fdt_property *fdt_get_property_namelen(const void *fdt,
 {
 	/* Prior to version 16, properties may need realignment
 	 * and this API does not work. fdt_getprop_*() will, however. */
-	if (fdt_version(fdt) < 0x10) {
+	if (_check1() && fdt_version(fdt) < 0x10) {
 		if (lenp)
 			*lenp = -FDT_ERR_BADVERSION;
 		return NULL;
@@ -455,8 +455,8 @@ const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
 		return NULL;
 
 	/* Handle realignment */
-	if (fdt_version(fdt) < 0x10 && (poffset + sizeof(*prop)) % 8 &&
-	    fdt32_ld(&prop->len) >= 8)
+	if (_check1() && fdt_version(fdt) < 0x10 &&
+	    (poffset + sizeof(*prop)) % 8 && fdt32_ld(&prop->len) >= 8)
 		return prop->data + 4;
 	return prop->data;
 }
@@ -488,8 +488,8 @@ const void *fdt_getprop_by_offset(const void *fdt, int offset,
 	}
 
 	/* Handle realignment */
-	if (fdt_version(fdt) < 0x10 && (offset + sizeof(*prop)) % 8 &&
-	    fdt32_ld(&prop->len) >= 8)
+	if (_check1() && fdt_version(fdt) < 0x10 &&
+	    (offset + sizeof(*prop)) % 8 && fdt32_ld(&prop->len) >= 8)
 		return prop->data + 4;
 	return prop->data;
 }
diff --git a/libfdt/fdt_rw.c b/libfdt/fdt_rw.c
index 4ff3aab..6d31d4e 100644
--- a/libfdt/fdt_rw.c
+++ b/libfdt/fdt_rw.c
@@ -26,7 +26,7 @@ static int fdt_blocks_misordered_(const void *fdt,
 
 static int fdt_rw_probe_(void *fdt)
 {
-	if (!_check2())
+	if (!_check1())
 		return 0;
 	FDT_RO_PROBE(fdt);
 
@@ -417,7 +417,7 @@ int fdt_open_into(const void *fdt, void *buf, int bufsize)
 	mem_rsv_size = (fdt_num_mem_rsv(fdt)+1)
 		* sizeof(struct fdt_reserve_entry);
 
-	if (fdt_version(fdt) >= 17) {
+	if (_check1() && fdt_version(fdt) >= 17) {
 		struct_size = fdt_size_dt_struct(fdt);
 	} else {
 		struct_size = 0;
diff --git a/libfdt/libfdt.h b/libfdt/libfdt.h
index 3277468..6025bbb 100644
--- a/libfdt/libfdt.h
+++ b/libfdt/libfdt.h
@@ -310,7 +310,7 @@ fdt_set_hdr_(size_dt_struct);
 size_t fdt_header_size_(uint32_t version);
 static inline size_t fdt_header_size(const void *fdt)
 {
-	return fdt_header_size_(fdt_version(fdt));
+	return _check1() ? fdt_header_size_(fdt_version(fdt)) : FDT_V17_SIZE;
 }
 
 /**
-- 
2.22.0.657.g960e92d24f-goog