igb: Add new function to read part number from EEPROM in string format

New adapters will have part numbers stored in string format rather than
simple hex format. This function will read part number formats in either
hex or string.

Signed-off-by: Carolyn Wyborny <carolyn.wyborny@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

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;