1 files changed, 87 insertions, 6 deletions

diff --git a/drivers/net/igb/e1000_nvm.c b/drivers/net/igb/e1000_nvm.c
index d83b77fa4038..6b5cc2cc453d 100644
--- a/drivers/net/igb/e1000_nvm.c
+++ b/drivers/net/igb/e1000_nvm.c
@@ -445,31 +445,112 @@ out:
 }
 
 /**
- *  igb_read_part_num - Read device part number
+ *  igb_read_part_string - Read device part number
  *  @hw: pointer to the HW structure
  *  @part_num: pointer to device part number
+ *  @part_num_size: size of part number buffer
  *
  *  Reads the product board assembly (PBA) number from the EEPROM and stores
  *  the value in part_num.
  **/
-s32 igb_read_part_num(struct e1000_hw *hw, u32 *part_num)
+s32 igb_read_part_string(struct e1000_hw *hw, u8 *part_num, u32 part_num_size)
 {
-	s32  ret_val;
+	s32 ret_val;
 	u16 nvm_data;
+	u16 pointer;
+	u16 offset;
+	u16 length;
+
+	if (part_num == NULL) {
+		hw_dbg("PBA string buffer was null\n");
+		ret_val = E1000_ERR_INVALID_ARGUMENT;
+		goto out;
+	}
 
 	ret_val = hw->nvm.ops.read(hw, NVM_PBA_OFFSET_0, 1, &nvm_data);
 	if (ret_val) {
 		hw_dbg("NVM Read Error\n");
 		goto out;
 	}
-	*part_num = (u32)(nvm_data << 16);
 
-	ret_val = hw->nvm.ops.read(hw, NVM_PBA_OFFSET_1, 1, &nvm_data);
+	ret_val = hw->nvm.ops.read(hw, NVM_PBA_OFFSET_1, 1, &pointer);
+	if (ret_val) {
+		hw_dbg("NVM Read Error\n");
+		goto out;
+	}
+
+	/*
+	 * if nvm_data is not ptr guard the PBA must be in legacy format which
+	 * means pointer is actually our second data word for the PBA number
+	 * and we can decode it into an ascii string
+	 */
+	if (nvm_data != NVM_PBA_PTR_GUARD) {
+		hw_dbg("NVM PBA number is not stored as string\n");
+
+		/* we will need 11 characters to store the PBA */
+		if (part_num_size < 11) {
+			hw_dbg("PBA string buffer too small\n");
+			return E1000_ERR_NO_SPACE;
+		}
+
+		/* extract hex string from data and pointer */
+		part_num[0] = (nvm_data >> 12) & 0xF;
+		part_num[1] = (nvm_data >> 8) & 0xF;
+		part_num[2] = (nvm_data >> 4) & 0xF;
+		part_num[3] = nvm_data & 0xF;
+		part_num[4] = (pointer >> 12) & 0xF;
+		part_num[5] = (pointer >> 8) & 0xF;
+		part_num[6] = '-';
+		part_num[7] = 0;
+		part_num[8] = (pointer >> 4) & 0xF;
+		part_num[9] = pointer & 0xF;
+
+		/* put a null character on the end of our string */
+		part_num[10] = '\0';
+
+		/* switch all the data but the '-' to hex char */
+		for (offset = 0; offset < 10; offset++) {
+			if (part_num[offset] < 0xA)
+				part_num[offset] += '0';
+			else if (part_num[offset] < 0x10)
+				part_num[offset] += 'A' - 0xA;
+		}
+
+		goto out;
+	}
+
+	ret_val = hw->nvm.ops.read(hw, pointer, 1, &length);
 	if (ret_val) {
 		hw_dbg("NVM Read Error\n");
 		goto out;
 	}
-	*part_num |= nvm_data;
+
+	if (length == 0xFFFF || length == 0) {
+		hw_dbg("NVM PBA number section invalid length\n");
+		ret_val = E1000_ERR_NVM_PBA_SECTION;
+		goto out;
+	}
+	/* check if part_num buffer is big enough */
+	if (part_num_size < (((u32)length * 2) - 1)) {
+		hw_dbg("PBA string buffer too small\n");
+		ret_val = E1000_ERR_NO_SPACE;
+		goto out;
+	}
+
+	/* trim pba length from start of string */
+	pointer++;
+	length--;
+
+	for (offset = 0; offset < length; offset++) {
+		ret_val = hw->nvm.ops.read(hw, pointer + offset, 1, &nvm_data);
+		if (ret_val) {
+			hw_dbg("NVM Read Error\n");
+			goto out;
+		}
+		part_num[offset * 2] = (u8)(nvm_data >> 8);
+		part_num[(offset * 2) + 1] = (u8)(nvm_data & 0xFF);
+	}
+	part_num[offset * 2] = '\0';
 
 out:
 	return ret_val;