i40e: Adding function for reading PBA String

Function will read PBA Block from Shadow RAM and return it in a string format.

Change-ID: I4ee7059f6e21bd0eba38687da15e772e0b4ab36e
Signed-off-by: Kamil Krawczyk <kamil.krawczyk@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/i40e/i40e_common.c

@@ -741,6 +741,65 @@ i40e_status i40e_get_san_mac_addr(struct i40e_hw *hw, u8 *mac_addr)
 }
 #endif
 
+/**
+ *  i40e_read_pba_string - Reads part number string from EEPROM
+ *  @hw: pointer to hardware structure
+ *  @pba_num: stores the part number string from the EEPROM
+ *  @pba_num_size: part number string buffer length
+ *
+ *  Reads the part number string from the EEPROM.
+ **/
+i40e_status i40e_read_pba_string(struct i40e_hw *hw, u8 *pba_num,
+				 u32 pba_num_size)
+{
+	i40e_status status = 0;
+	u16 pba_word = 0;
+	u16 pba_size = 0;
+	u16 pba_ptr = 0;
+	u16 i = 0;
+
+	status = i40e_read_nvm_word(hw, I40E_SR_PBA_FLAGS, &pba_word);
+	if (status || (pba_word != 0xFAFA)) {
+		hw_dbg(hw, "Failed to read PBA flags or flag is invalid.\n");
+		return status;
+	}
+
+	status = i40e_read_nvm_word(hw, I40E_SR_PBA_BLOCK_PTR, &pba_ptr);
+	if (status) {
+		hw_dbg(hw, "Failed to read PBA Block pointer.\n");
+		return status;
+	}
+
+	status = i40e_read_nvm_word(hw, pba_ptr, &pba_size);
+	if (status) {
+		hw_dbg(hw, "Failed to read PBA Block size.\n");
+		return status;
+	}
+
+	/* Subtract one to get PBA word count (PBA Size word is included in
+	 * total size)
+	 */
+	pba_size--;
+	if (pba_num_size < (((u32)pba_size * 2) + 1)) {
+		hw_dbg(hw, "Buffer to small for PBA data.\n");
+		return I40E_ERR_PARAM;
+	}
+
+	for (i = 0; i < pba_size; i++) {
+		status = i40e_read_nvm_word(hw, (pba_ptr + 1) + i, &pba_word);
+		if (status) {
+			hw_dbg(hw, "Failed to read PBA Block word %d.\n", i);
+			return status;
+		}
+
+		pba_num[(i * 2)] = (pba_word >> 8) & 0xFF;
+		pba_num[(i * 2) + 1] = pba_word & 0xFF;
+	}
+	pba_num[(pba_size * 2)] = '\0';
+
+	return status;
+}
+
 /**
  * i40e_get_media_type - Gets media type
  * @hw: pointer to the hardware structure

drivers/net/ethernet/intel/i40e/i40e_prototype.h

@@ -248,6 +248,8 @@ void i40e_clear_pxe_mode(struct i40e_hw *hw);
 bool i40e_get_link_status(struct i40e_hw *hw);
 i40e_status i40e_get_mac_addr(struct i40e_hw *hw, u8 *mac_addr);
 i40e_status i40e_get_port_mac_addr(struct i40e_hw *hw, u8 *mac_addr);
+i40e_status i40e_read_pba_string(struct i40e_hw *hw, u8 *pba_num,
+				 u32 pba_num_size);
 i40e_status i40e_validate_mac_addr(u8 *mac_addr);
 void i40e_pre_tx_queue_cfg(struct i40e_hw *hw, u32 queue, bool enable);
 #ifdef I40E_FCOE

drivers/net/ethernet/intel/i40e/i40e_type.h

@@ -1140,6 +1140,8 @@ struct i40e_hw_port_stats {
 /* Checksum and Shadow RAM pointers */
 #define I40E_SR_NVM_CONTROL_WORD		0x00
 #define I40E_SR_EMP_MODULE_PTR			0x0F
+#define I40E_SR_PBA_FLAGS			0x15
+#define I40E_SR_PBA_BLOCK_PTR			0x16
 #define I40E_SR_NVM_IMAGE_VERSION		0x18
 #define I40E_SR_NVM_WAKE_ON_LAN			0x19
 #define I40E_SR_ALTERNATE_SAN_MAC_ADDRESS_PTR	0x27