[PATCH] fru: ops: Display FRU fields properly for 0xc1 fields

[Michal Simek <michal.simek@amd.com>]

From: Algapally Santosh Sagar <santoshsagar.algapally@amd.com>

FRU data is not displayed properly in case of 0xc1 fields.
The 0xC1 can be used in two cases.
1. Char record type 8-bit ASCII + Latin 1 with length of 1.
(For example board revision 'A')

2. C1h (type/length byte encoded to indicate no more info fields).
which can follow by 00h to fill all remaining unused space

Hence removed the check end-of-the field c1 to allow c1 fields.

"ASCII+LATIN1" is defined as the printable characters from the
first set of 256 characters of Unicode 6.2 (U+0000h through U+00FFh,
inclusive) expressed as an eight-bit value. (Unicode follows ISO/IEC
8859-1 in the layout of printable characters up to U+00FFh).

So, print only printable chars and limit range from 0x20 ' ' to 0x7e '-'
which will be also indication if 0xc1 behaves as record with one char or
end of record.

Signed-off-by: Algapally Santosh Sagar <santoshsagar.algapally@amd.com>
Signed-off-by: Michal Simek <michal.simek@amd.com>
---

 board/xilinx/common/fru_ops.c | 43 +++++++++++++++++++++++------------
 1 file changed, 28 insertions(+), 15 deletions(-)

diff --git a/board/xilinx/common/fru_ops.c b/board/xilinx/common/fru_ops.c
index c4f009affc5e..167252c240cd 100644
--- a/board/xilinx/common/fru_ops.c
+++ b/board/xilinx/common/fru_ops.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- * (C) Copyright 2019 - 2020 Xilinx, Inc.
+ * (C) Copyright 2019 - 2022, Xilinx, Inc.
+ * (C) Copyright 2022 - 2023, Advanced Micro Devices, Inc.
  */
 
 #include <common.h>
@@ -61,9 +62,6 @@ static int fru_check_type_len(u8 type_len, u8 language, u8 *type)
 {
 	int len;
 
-	if (type_len == FRU_TYPELEN_EOF)
-		return -EINVAL;
-
 	*type = (type_len & FRU_TYPELEN_CODE_MASK) >> FRU_TYPELEN_TYPE_SHIFT;
 
 	len = type_len & FRU_TYPELEN_LEN_MASK;
@@ -172,9 +170,16 @@ static int fru_parse_board(unsigned long addr)
 {
 	u8 i, type;
 	int len;
-	u8 *data, *term, *limit;
+	u8 *data, *term, *limit, *next_addr, *eof;
 
 	memcpy(&fru_data.brd.ver, (void *)addr, 6);
+
+	/*
+	 * eof marks the last data byte (without checksum). That's why checksum
+	 * is address length - 1 and last data byte is length - 2.
+	 */
+	eof = (u8 *)(fru_data.brd.len * 8 + addr - 2);
+
 	addr += 6;
 	data = (u8 *)&fru_data.brd.manufacturer_type_len;
 
@@ -184,10 +189,21 @@ static int fru_parse_board(unsigned long addr)
 	for (i = 0; ; i++, data += FRU_BOARD_MAX_LEN) {
 		len = fru_check_type_len(*(u8 *)addr, fru_data.brd.lang_code,
 					 &type);
+		next_addr = (u8 *)addr + 1;
+
+		if ((u8 *)addr >= eof) {
+			debug("Reach EOF record: addr %lx, eof %lx\n", addr,
+			      (unsigned long)eof);
+			break;
+		}
+
 		/*
-		 * Stop cature if it end of fields
+		 * Stop capture if the type is ASCII and valid field length
+		 * is 1 (0xc1) and next FRU data is less than 0x20 (space " ")
+		 * or it is 0x7f (delete 'DEL').
 		 */
-		if (len == -EINVAL)
+		if (type == FRU_TYPELEN_TYPE_ASCII8 && len == 1	&&
+		    (*next_addr < 0x20 || *next_addr == 0x7F))
 			break;
 
 		/* Stop when amount of chars is more then fields to record */
@@ -332,9 +348,11 @@ static int fru_display_board(struct fru_board_data *brd, int verbose)
 	for (u8 i = 0; i < (sizeof(boardinfo) / sizeof(*boardinfo)); i++) {
 		len = fru_check_type_len(*data++, brd->lang_code,
 					 &type);
-		if (len == -EINVAL) {
-			printf("**** EOF for Board Area ****\n");
-			break;
+
+		/* Empty record has no len/type filled */
+		if (!len) {
+			debug("%s not found\n", boardinfo[i]);
+			continue;
 		}
 
 		if (type <= FRU_TYPELEN_TYPE_ASCII8 &&
@@ -344,11 +362,6 @@ static int fru_display_board(struct fru_board_data *brd, int verbose)
 		else
 			debug("Type code: %s\n", typecode[type + 1]);
 
-		if (!len) {
-			debug("%s not found\n", boardinfo[i]);
-			continue;
-		}
-
 		switch (type) {
 		case FRU_TYPELEN_TYPE_BINARY:
 			debug("Length: %d\n", len);
-- 
2.36.1