ixgbe: Add support for NVM handling in E610 device

Add low level support for accessing NVM in E610 device. NVM operations are
handled via the Admin Command Interface. Add the following NVM specific
operations:
- acquire, release, read
- validate checksum
- read shadow ram

Co-developed-by: Stefan Wegrzyn <[email protected]>
Signed-off-by: Stefan Wegrzyn <[email protected]>
Co-developed-by: Jedrzej Jagielski <[email protected]>
Signed-off-by: Jedrzej Jagielski <[email protected]>
Reviewed-by: Michal Swiatkowski <[email protected]>
Reviewed-by: Simon Horman <[email protected]>
Tested-by: Bharath R <[email protected]>
Signed-off-by: Piotr Kwapulinski <[email protected]>
Signed-off-by: Tony Nguyen <[email protected]>

Author: pkwapuli

drivers/net/ethernet/intel/ixgbe/ixgbe_e610.c

@@ -2105,3 +2105,294 @@ int ixgbe_aci_get_netlist_node(struct ixgbe_hw *hw,
 
 	return 0;
 }
+
+/**
+ * ixgbe_acquire_nvm - Generic request for acquiring the NVM ownership
+ * @hw: pointer to the HW structure
+ * @access: NVM access type (read or write)
+ *
+ * Request NVM ownership.
+ *
+ * Return: the exit code of the operation.
+ */
+int ixgbe_acquire_nvm(struct ixgbe_hw *hw,
+		      enum ixgbe_aci_res_access_type access)
+{
+	u32 fla;
+
+	/* Skip if we are in blank NVM programming mode */
+	fla = IXGBE_READ_REG(hw, IXGBE_GLNVM_FLA);
+	if ((fla & IXGBE_GLNVM_FLA_LOCKED_M) == 0)
+		return 0;
+
+	return ixgbe_acquire_res(hw, IXGBE_NVM_RES_ID, access,
+				 IXGBE_NVM_TIMEOUT);
+}
+
+/**
+ * ixgbe_release_nvm - Generic request for releasing the NVM ownership
+ * @hw: pointer to the HW structure
+ *
+ * Release NVM ownership.
+ */
+void ixgbe_release_nvm(struct ixgbe_hw *hw)
+{
+	u32 fla;
+
+	/* Skip if we are in blank NVM programming mode */
+	fla = IXGBE_READ_REG(hw, IXGBE_GLNVM_FLA);
+	if ((fla & IXGBE_GLNVM_FLA_LOCKED_M) == 0)
+		return;
+
+	ixgbe_release_res(hw, IXGBE_NVM_RES_ID);
+}
+
+/**
+ * ixgbe_aci_read_nvm - read NVM
+ * @hw: pointer to the HW struct
+ * @module_typeid: module pointer location in words from the NVM beginning
+ * @offset: byte offset from the module beginning
+ * @length: length of the section to be read (in bytes from the offset)
+ * @data: command buffer (size [bytes] = length)
+ * @last_command: tells if this is the last command in a series
+ * @read_shadow_ram: tell if this is a shadow RAM read
+ *
+ * Read the NVM using ACI command (0x0701).
+ *
+ * Return: the exit code of the operation.
+ */
+int ixgbe_aci_read_nvm(struct ixgbe_hw *hw, u16 module_typeid, u32 offset,
+		       u16 length, void *data, bool last_command,
+		       bool read_shadow_ram)
+{
+	struct ixgbe_aci_cmd_nvm *cmd;
+	struct ixgbe_aci_desc desc;
+
+	if (offset > IXGBE_ACI_NVM_MAX_OFFSET)
+		return -EINVAL;
+
+	cmd = &desc.params.nvm;
+
+	ixgbe_fill_dflt_direct_cmd_desc(&desc, ixgbe_aci_opc_nvm_read);
+
+	if (!read_shadow_ram && module_typeid == IXGBE_ACI_NVM_START_POINT)
+		cmd->cmd_flags |= IXGBE_ACI_NVM_FLASH_ONLY;
+
+	/* If this is the last command in a series, set the proper flag. */
+	if (last_command)
+		cmd->cmd_flags |= IXGBE_ACI_NVM_LAST_CMD;
+	cmd->module_typeid = cpu_to_le16(module_typeid);
+	cmd->offset_low = cpu_to_le16(offset & 0xFFFF);
+	cmd->offset_high = (offset >> 16) & 0xFF;
+	cmd->length = cpu_to_le16(length);
+
+	return ixgbe_aci_send_cmd(hw, &desc, data, length);
+}
+
+/**
+ * ixgbe_nvm_validate_checksum - validate checksum
+ * @hw: pointer to the HW struct
+ *
+ * Verify NVM PFA checksum validity using ACI command (0x0706).
+ * If the checksum verification failed, IXGBE_ERR_NVM_CHECKSUM is returned.
+ * The function acquires and then releases the NVM ownership.
+ *
+ * Return: the exit code of the operation.
+ */
+int ixgbe_nvm_validate_checksum(struct ixgbe_hw *hw)
+{
+	struct ixgbe_aci_cmd_nvm_checksum *cmd;
+	struct ixgbe_aci_desc desc;
+	int err;
+
+	err = ixgbe_acquire_nvm(hw, IXGBE_RES_READ);
+	if (err)
+		return err;
+
+	cmd = &desc.params.nvm_checksum;
+
+	ixgbe_fill_dflt_direct_cmd_desc(&desc, ixgbe_aci_opc_nvm_checksum);
+	cmd->flags = IXGBE_ACI_NVM_CHECKSUM_VERIFY;
+
+	err = ixgbe_aci_send_cmd(hw, &desc, NULL, 0);
+
+	ixgbe_release_nvm(hw);
+
+	if (!err && cmd->checksum !=
+		cpu_to_le16(IXGBE_ACI_NVM_CHECKSUM_CORRECT)) {
+		struct ixgbe_adapter *adapter = container_of(hw, struct ixgbe_adapter,
+							     hw);
+
+		err = -EIO;
+		netdev_err(adapter->netdev, "Invalid Shadow Ram checksum");
+	}
+
+	return err;
+}
+
+/**
+ * ixgbe_read_sr_word_aci - Reads Shadow RAM via ACI
+ * @hw: pointer to the HW structure
+ * @offset: offset of the Shadow RAM word to read (0x000000 - 0x001FFF)
+ * @data: word read from the Shadow RAM
+ *
+ * Reads one 16 bit word from the Shadow RAM using ixgbe_read_flat_nvm.
+ *
+ * Return: the exit code of the operation.
+ */
+int ixgbe_read_sr_word_aci(struct ixgbe_hw  *hw, u16 offset, u16 *data)
+{
+	u32 bytes = sizeof(u16);
+	u16 data_local;
+	int err;
+
+	err = ixgbe_read_flat_nvm(hw, offset * sizeof(u16), &bytes,
+				  (u8 *)&data_local, true);
+	if (err)
+		return err;
+
+	*data = data_local;
+	return 0;
+}
+
+/**
+ * ixgbe_read_flat_nvm - Read portion of NVM by flat offset
+ * @hw: pointer to the HW struct
+ * @offset: offset from beginning of NVM
+ * @length: (in) number of bytes to read; (out) number of bytes actually read
+ * @data: buffer to return data in (sized to fit the specified length)
+ * @read_shadow_ram: if true, read from shadow RAM instead of NVM
+ *
+ * Reads a portion of the NVM, as a flat memory space. This function correctly
+ * breaks read requests across Shadow RAM sectors, prevents Shadow RAM size
+ * from being exceeded in case of Shadow RAM read requests and ensures that no
+ * single read request exceeds the maximum 4KB read for a single admin command.
+ *
+ * Returns an error code on failure. Note that the data pointer may be
+ * partially updated if some reads succeed before a failure.
+ *
+ * Return: the exit code of the operation.
+ */
+int ixgbe_read_flat_nvm(struct ixgbe_hw  *hw, u32 offset, u32 *length,
+			u8 *data, bool read_shadow_ram)
+{
+	u32 inlen = *length;
+	u32 bytes_read = 0;
+	bool last_cmd;
+	int err;
+
+	/* Verify the length of the read if this is for the Shadow RAM */
+	if (read_shadow_ram && ((offset + inlen) >
+				(hw->eeprom.word_size * 2u)))
+		return -EINVAL;
+
+	do {
+		u32 read_size, sector_offset;
+
+		/* ixgbe_aci_read_nvm cannot read more than 4KB at a time.
+		 * Additionally, a read from the Shadow RAM may not cross over
+		 * a sector boundary. Conveniently, the sector size is also 4KB.
+		 */
+		sector_offset = offset % IXGBE_ACI_MAX_BUFFER_SIZE;
+		read_size = min_t(u32,
+				  IXGBE_ACI_MAX_BUFFER_SIZE - sector_offset,
+				  inlen - bytes_read);
+
+		last_cmd = !(bytes_read + read_size < inlen);
+
+		/* ixgbe_aci_read_nvm takes the length as a u16. Our read_size
+		 * is calculated using a u32, but the IXGBE_ACI_MAX_BUFFER_SIZE
+		 * maximum size guarantees that it will fit within the 2 bytes.
+		 */
+		err = ixgbe_aci_read_nvm(hw, IXGBE_ACI_NVM_START_POINT,
+					 offset, (u16)read_size,
+					 data + bytes_read, last_cmd,
+					 read_shadow_ram);
+		if (err)
+			break;
+
+		bytes_read += read_size;
+		offset += read_size;
+	} while (!last_cmd);
+
+	*length = bytes_read;
+	return err;
+}
+
+/**
+ * ixgbe_read_ee_aci_e610 - Read EEPROM word using the admin command.
+ * @hw: pointer to hardware structure
+ * @offset: offset of  word in the EEPROM to read
+ * @data: word read from the EEPROM
+ *
+ * Reads a 16 bit word from the EEPROM using the ACI.
+ * If the EEPROM params are not initialized, the function
+ * initialize them before proceeding with reading.
+ * The function acquires and then releases the NVM ownership.
+ *
+ * Return: the exit code of the operation.
+ */
+int ixgbe_read_ee_aci_e610(struct ixgbe_hw *hw, u16 offset, u16 *data)
+{
+	int err;
+
+	if (hw->eeprom.type == ixgbe_eeprom_uninitialized) {
+		err = hw->eeprom.ops.init_params(hw);
+		if (err)
+			return err;
+	}
+
+	err = ixgbe_acquire_nvm(hw, IXGBE_RES_READ);
+	if (err)
+		return err;
+
+	err = ixgbe_read_sr_word_aci(hw, offset, data);
+	ixgbe_release_nvm(hw);
+
+	return err;
+}
+
+/**
+ * ixgbe_validate_eeprom_checksum_e610 - Validate EEPROM checksum
+ * @hw: pointer to hardware structure
+ * @checksum_val: calculated checksum
+ *
+ * Performs checksum calculation and validates the EEPROM checksum. If the
+ * caller does not need checksum_val, the value can be NULL.
+ * If the EEPROM params are not initialized, the function
+ * initialize them before proceeding.
+ * The function acquires and then releases the NVM ownership.
+ *
+ * Return: the exit code of the operation.
+ */
+int ixgbe_validate_eeprom_checksum_e610(struct ixgbe_hw *hw, u16 *checksum_val)
+{
+	int err;
+
+	if (hw->eeprom.type == ixgbe_eeprom_uninitialized) {
+		err = hw->eeprom.ops.init_params(hw);
+		if (err)
+			return err;
+	}
+
+	err = ixgbe_nvm_validate_checksum(hw);
+	if (err)
+		return err;
+
+	if (checksum_val) {
+		u16 tmp_checksum;
+
+		err = ixgbe_acquire_nvm(hw, IXGBE_RES_READ);
+		if (err)
+			return err;
+
+		err = ixgbe_read_sr_word_aci(hw, E610_SR_SW_CHECKSUM_WORD,
+					     &tmp_checksum);
+		ixgbe_release_nvm(hw);
+
+		if (!err)
+			*checksum_val = tmp_checksum;
+	}
+
+	return err;
+}

drivers/net/ethernet/intel/ixgbe/ixgbe_e610.h

@@ -59,5 +59,17 @@ int ixgbe_enter_lplu_e610(struct ixgbe_hw *hw);
 int ixgbe_aci_get_netlist_node(struct ixgbe_hw *hw,
 			       struct ixgbe_aci_cmd_get_link_topo *cmd,
 			       u8 *node_part_number, u16 *node_handle);
+int ixgbe_acquire_nvm(struct ixgbe_hw *hw,
+		      enum ixgbe_aci_res_access_type access);
+void ixgbe_release_nvm(struct ixgbe_hw *hw);
+int ixgbe_aci_read_nvm(struct ixgbe_hw *hw, u16 module_typeid, u32 offset,
+		       u16 length, void *data, bool last_command,
+		       bool read_shadow_ram);
+int ixgbe_nvm_validate_checksum(struct ixgbe_hw *hw);
+int ixgbe_read_sr_word_aci(struct ixgbe_hw  *hw, u16 offset, u16 *data);
+int ixgbe_read_flat_nvm(struct ixgbe_hw  *hw, u32 offset, u32 *length,
+			u8 *data, bool read_shadow_ram);
+int ixgbe_read_ee_aci_e610(struct ixgbe_hw *hw, u16 offset, u16 *data);
+int ixgbe_validate_eeprom_checksum_e610(struct ixgbe_hw *hw, u16 *checksum_val);
 
 #endif /* _IXGBE_E610_H_ */