Add an option to pad the blob that is generated

There are times when we need extra space in the blob and just want
to have it added on w/o know the exact size to make it.

The padding and min size options are mutually exclusive.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

1 files changed, 13 insertions, 7 deletions

diff --git a/flattree.c b/flattree.c
index c1032d1..c860b63 100644
--- a/flattree.c
+++ b/flattree.c
@@ -367,7 +367,7 @@ void dt_to_blob(FILE *f, struct boot_info *bi, int version,
 	struct data dtbuf      = empty_data;
 	struct data strbuf     = empty_data;
 	struct fdt_header fdt;
-	int padlen;
+	int padlen = 0;
 
 	for (i = 0; i < ARRAY_SIZE(version_table); i++) {
 		if (version_table[i].version == version)
@@ -388,16 +388,17 @@ void dt_to_blob(FILE *f, struct boot_info *bi, int version,
 	/*
 	 * If the user asked for more space than is used, adjust the totalsize.
 	 */
-	padlen = minsize - be32_to_cpu(fdt.totalsize);
-	if (padlen > 0) {
-		fdt.totalsize = cpu_to_be32(minsize);
-	} else {
-		if ((minsize > 0) && (quiet < 1))
+	if (minsize > 0) {
+		padlen = minsize - be32_to_cpu(fdt.totalsize);
+		if ((padlen < 0) && (quiet < 1))
 			fprintf(stderr,
 				"Warning: blob size %d >= minimum size %d\n",
 				be32_to_cpu(fdt.totalsize), minsize);
 	}
 
+	if (padsize > 0)
+		padlen = padsize;
+
 	/*
 	 * Assemble the blob: start with the header, add with alignment
 	 * the reserve buffer, add the reserve map terminating zeroes,
@@ -414,8 +415,10 @@ void dt_to_blob(FILE *f, struct boot_info *bi, int version,
 	 * If the user asked for more space than is used, pad out the blob.
 	 */
 	if (padlen > 0) {
+		int tsize = be32_to_cpu(fdt.totalsize);
+		tsize += padlen;
 		blob = data_append_zeroes(blob, padlen);
-		fdt.totalsize = cpu_to_be32(minsize);
+		fdt.totalsize = cpu_to_be32(tsize);
 	}
 
 	fwrite(blob.val, blob.len, 1, f);
@@ -545,6 +548,9 @@ void dt_to_asm(FILE *f, struct boot_info *bi, int version, int boot_cpuid_phys)
 		fprintf(f, "\t.space\t%d - (_%s_blob_end - _%s_blob_start), 0\n",
 			minsize, symprefix, symprefix);
 	}
+	if (padsize > 0) {
+		fprintf(f, "\t.space\t%d, 0\n", padsize);
+	}
 	emit_label(f, symprefix, "blob_abs_end");
 
 	data_free(strbuf);