xilinx: cmd: Add basic fru format generator

Idea is to have something what can be used for board bringup from
generic board perspective.

There is a violation compare to spec that FRU ID is ASCII8 instead of
binary format but this is really for having something to pass boot and
boot to OS which has better generating options.
Also time should be filled properly.

For example:
fru board_gen 1000 XILINX versal-x-prc-01-revA serialX partX

There is also support for revision field which is Xilinx specific field.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/board/xilinx/common/fru_ops.c b/board/xilinx/common/fru_ops.c
index 491e92a..fc3add7 100644
--- a/board/xilinx/common/fru_ops.c
+++ b/board/xilinx/common/fru_ops.c
@@ -62,6 +62,103 @@
 	return len;
 }
 
+/* Return len */
+static u8 fru_gen_type_len(u8 *addr, char *name)
+{
+	int len = strlen(name);
+	struct fru_board_info_member *member;
+
+	member = (struct fru_board_info_member *)addr;
+	member->type_len = FRU_TYPELEN_TYPE_ASCII8 << FRU_TYPELEN_TYPE_SHIFT;
+	member->type_len |= len;
+
+	debug("%lx/%lx: Add %s to 0x%lx (len 0x%x)\n", (ulong)addr,
+	      (ulong)&member->type_len,  name, (ulong)&member->name, len);
+	memcpy(&member->name, name, len);
+
+	/* Add +1 for type_len parameter */
+	return 1 + len;
+}
+
+int fru_generate(unsigned long addr, char *manufacturer, char *board_name,
+		 char *serial_no, char *part_no, char *revision)
+{
+	struct fru_common_hdr *header = (struct fru_common_hdr *)addr;
+	struct fru_board_info_header *board_info;
+	u8 *member;
+	u8 len, pad, modulo;
+
+	header->version = 1; /* Only version 1.0 is supported now */
+	header->off_internal = 0; /* not present */
+	header->off_chassis = 0; /* not present */
+	header->off_board = (sizeof(*header)) / 8; /* Starting offset 8 */
+	header->off_product = 0; /* not present */
+	header->off_multirec = 0; /* not present */
+	header->pad = 0;
+	/*
+	 * This unsigned byte can be used to calculate a zero checksum
+	 * for the data area following the header. I.e. the modulo 256 sum of
+	 * the record data bytes plus the checksum byte equals zero.
+	 */
+	header->crc = 0; /* Clear before calculation */
+	header->crc = 0 - fru_checksum((u8 *)header, sizeof(*header));
+
+	/* board info is just right after header */
+	board_info = (void *)((u8 *)header + sizeof(*header));
+
+	debug("header %lx, board_info %lx\n", (ulong)header, (ulong)board_info);
+
+	board_info->ver = 1; /* 1.0 spec */
+	board_info->lang_code = 0; /* English */
+	board_info->time[0] = 0; /* unspecified */
+	board_info->time[1] = 0; /* unspecified */
+	board_info->time[2] = 0; /* unspecified */
+
+	/* Member fields are just after board_info header */
+	member = (u8 *)board_info + sizeof(*board_info);
+
+	len = fru_gen_type_len(member, manufacturer); /* Board Manufacturer */
+	member += len;
+	len = fru_gen_type_len(member, board_name); /* Board Product name */
+	member += len;
+	len = fru_gen_type_len(member, serial_no); /* Board Serial number */
+	member += len;
+	len = fru_gen_type_len(member, part_no); /* Board part number */
+	member += len;
+	len = fru_gen_type_len(member, "U-Boot generator"); /* File ID */
+	member += len;
+	len = fru_gen_type_len(member, revision); /* Revision */
+	member += len;
+
+	*member++ = 0xc1; /* Indication of no more fields */
+
+	len = member - (u8 *)board_info; /* Find current length */
+	len += 1; /* Add checksum there too for calculation */
+
+	modulo = len % 8;
+
+	if (modulo) {
+		/* Do not fill last item which is checksum */
+		for (pad = 0; pad < 8 - modulo; pad++)
+			*member++ = 0;
+
+		/* Increase structure size */
+		len += 8 - modulo;
+	}
+
+	board_info->len = len / 8; /* Size in multiples of 8 bytes */
+
+	*member = 0; /* Clear before calculation */
+	*member = 0 - fru_checksum((u8 *)board_info, len);
+
+	debug("checksum %x(addr %x)\n", *member, len);
+
+	env_set_hex("fru_addr", addr);
+	env_set_hex("filesize", (unsigned long)member - addr + 1);
+
+	return 0;
+}
+
 static int fru_parse_board(unsigned long addr)
 {
 	u8 i, type;
@@ -153,7 +250,9 @@
 		"Product Name",
 		"Serial No",
 		"Part Number",
-		"File ID"
+		"File ID",
+		/* Xilinx spec */
+		"Revision Number",
 	};
 
 	if (verbose) {