add SERCOM peripheral for UART debug

currently only the SERCOM peripheral driver is added an configured,
but it is not being used.
UART debug will be done through the EDBG COM port, on PB24/PB25 of
SAM E54 Xplained Pro board

Change-Id: Id7af37ce1dd2d0a356e019c96bf6438ce459411b
diff --git a/sysmoOCTSIM/hal/include/hpl_usart_async.h b/sysmoOCTSIM/hal/include/hpl_usart_async.h
new file mode 100644
index 0000000..3f833d1
--- /dev/null
+++ b/sysmoOCTSIM/hal/include/hpl_usart_async.h
@@ -0,0 +1,270 @@
+/**
+ * \file
+ *
+ * \brief USART related functionality declaration.
+ *
+ * Copyright (c) 2014-2018 Microchip Technology Inc. and its subsidiaries.
+ *
+ * \asf_license_start
+ *
+ * \page License
+ *
+ * Subject to your compliance with these terms, you may use Microchip
+ * software and any derivatives exclusively with Microchip products.
+ * It is your responsibility to comply with third party license terms applicable
+ * to your use of third party software (including open source software) that
+ * may accompany Microchip software.
+ *
+ * THIS SOFTWARE IS SUPPLIED BY MICROCHIP "AS IS". NO WARRANTIES,
+ * WHETHER EXPRESS, IMPLIED OR STATUTORY, APPLY TO THIS SOFTWARE,
+ * INCLUDING ANY IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY,
+ * AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT WILL MICROCHIP BE
+ * LIABLE FOR ANY INDIRECT, SPECIAL, PUNITIVE, INCIDENTAL OR CONSEQUENTIAL
+ * LOSS, DAMAGE, COST OR EXPENSE OF ANY KIND WHATSOEVER RELATED TO THE
+ * SOFTWARE, HOWEVER CAUSED, EVEN IF MICROCHIP HAS BEEN ADVISED OF THE
+ * POSSIBILITY OR THE DAMAGES ARE FORESEEABLE.  TO THE FULLEST EXTENT
+ * ALLOWED BY LAW, MICROCHIP'S TOTAL LIABILITY ON ALL CLAIMS IN ANY WAY
+ * RELATED TO THIS SOFTWARE WILL NOT EXCEED THE AMOUNT OF FEES, IF ANY,
+ * THAT YOU HAVE PAID DIRECTLY TO MICROCHIP FOR THIS SOFTWARE.
+ *
+ * \asf_license_stop
+ *
+ */
+
+#ifndef _HPL_USART_ASYNC_H_INCLUDED
+#define _HPL_USART_ASYNC_H_INCLUDED
+
+/**
+ * \addtogroup HPL USART
+ *
+ * \section hpl_usart_rev Revision History
+ * - v1.0.0 Initial Release
+ *
+ *@{
+ */
+
+#include "hpl_usart.h"
+#include "hpl_irq.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * \brief USART callback types
+ */
+enum _usart_async_callback_type { USART_ASYNC_BYTE_SENT, USART_ASYNC_RX_DONE, USART_ASYNC_TX_DONE, USART_ASYNC_ERROR };
+
+/**
+ * \brief USART device structure
+ *
+ * The USART device structure forward declaration.
+ */
+struct _usart_async_device;
+
+/**
+ * \brief USART interrupt callbacks
+ */
+struct _usart_async_callbacks {
+	void (*tx_byte_sent)(struct _usart_async_device *device);
+	void (*rx_done_cb)(struct _usart_async_device *device, uint8_t data);
+	void (*tx_done_cb)(struct _usart_async_device *device);
+	void (*error_cb)(struct _usart_async_device *device);
+};
+
+/**
+ * \brief USART descriptor device structure
+ */
+struct _usart_async_device {
+	struct _usart_async_callbacks usart_cb;
+	struct _irq_descriptor        irq;
+	void *                        hw;
+};
+/**
+ * \name HPL functions
+ */
+//@{
+/**
+ * \brief Initialize asynchronous USART
+ *
+ * This function does low level USART configuration.
+ *
+ * \param[in] device The pointer to USART device instance
+ * \param[in] hw The pointer to hardware instance
+ *
+ * \return Initialization status
+ */
+int32_t _usart_async_init(struct _usart_async_device *const device, void *const hw);
+
+/**
+ * \brief Deinitialize USART
+ *
+ * This function closes the given USART by disabling its clock.
+ *
+ * \param[in] device The pointer to USART device instance
+ */
+void _usart_async_deinit(struct _usart_async_device *const device);
+
+/**
+ * \brief Enable usart module
+ *
+ * This function will enable the usart module
+ *
+ * \param[in] device The pointer to USART device instance
+ */
+void _usart_async_enable(struct _usart_async_device *const device);
+
+/**
+ * \brief Disable usart module
+ *
+ * This function will disable the usart module
+ *
+ * \param[in] device The pointer to USART device instance
+ */
+void _usart_async_disable(struct _usart_async_device *const device);
+
+/**
+ * \brief Calculate baud rate register value
+ *
+ * \param[in] baud Required baud rate
+ * \param[in] clock_rate clock frequency
+ * \param[in] samples The number of samples
+ * \param[in] mode USART mode
+ * \param[in] fraction A fraction value
+ *
+ * \return Calculated baud rate register value
+ */
+uint16_t _usart_async_calculate_baud_rate(const uint32_t baud, const uint32_t clock_rate, const uint8_t samples,
+                                          const enum usart_baud_rate_mode mode, const uint8_t fraction);
+
+/**
+ * \brief Set baud rate
+ *
+ * \param[in] device The pointer to USART device instance
+ * \param[in] baud_rate A baud rate to set
+ */
+void _usart_async_set_baud_rate(struct _usart_async_device *const device, const uint32_t baud_rate);
+
+/**
+ * \brief Set data order
+ *
+ * \param[in] device The pointer to USART device instance
+ * \param[in] order A data order to set
+ */
+void _usart_async_set_data_order(struct _usart_async_device *const device, const enum usart_data_order order);
+
+/**
+ * \brief Set mode
+ *
+ * \param[in] device The pointer to USART device instance
+ * \param[in] mode A mode to set
+ */
+void _usart_async_set_mode(struct _usart_async_device *const device, const enum usart_mode mode);
+
+/**
+ * \brief Set parity
+ *
+ * \param[in] device The pointer to USART device instance
+ * \param[in] parity A parity to set
+ */
+void _usart_async_set_parity(struct _usart_async_device *const device, const enum usart_parity parity);
+
+/**
+ * \brief Set stop bits mode
+ *
+ * \param[in] device The pointer to USART device instance
+ * \param[in] stop_bits A stop bits mode to set
+ */
+void _usart_async_set_stop_bits(struct _usart_async_device *const device, const enum usart_stop_bits stop_bits);
+
+/**
+ * \brief Set character size
+ *
+ * \param[in] device The pointer to USART device instance
+ * \param[in] size A character size to set
+ */
+void _usart_async_set_character_size(struct _usart_async_device *const device, const enum usart_character_size size);
+
+/**
+ * \brief Retrieve usart status
+ *
+ * \param[in] device The pointer to USART device instance
+ */
+uint32_t _usart_async_get_status(const struct _usart_async_device *const device);
+
+/**
+ * \brief Write a byte to the given USART instance
+ *
+ * \param[in] device The pointer to USART device instance
+ * \param[in] data Data to write
+ */
+void _usart_async_write_byte(struct _usart_async_device *const device, uint8_t data);
+
+/**
+ * \brief Check if USART is ready to send next byte
+ *
+ * \param[in] device The pointer to USART device instance
+ *
+ * \return Status of the ready check.
+ * \retval true if the USART is ready to send next byte
+ * \retval false if the USART is not ready to send next byte
+ */
+bool _usart_async_is_byte_sent(const struct _usart_async_device *const device);
+
+/**
+ * \brief Set the state of flow control pins
+ *
+ * \param[in] device The pointer to USART device instance
+ * \param[in] state - A state of flow control pins to set
+ */
+void _usart_async_set_flow_control_state(struct _usart_async_device *const    device,
+                                         const union usart_flow_control_state state);
+
+/**
+ * \brief Retrieve the state of flow control pins
+ *
+ * This function retrieves the of flow control pins.
+ *
+ * \return USART_FLOW_CONTROL_STATE_UNAVAILABLE.
+ */
+union usart_flow_control_state _usart_async_get_flow_control_state(const struct _usart_async_device *const device);
+
+/**
+ * \brief Enable data register empty interrupt
+ *
+ * \param[in] device The pointer to USART device instance
+ */
+void _usart_async_enable_byte_sent_irq(struct _usart_async_device *const device);
+
+/**
+ * \brief Enable transmission complete interrupt
+ *
+ * \param[in] device The pointer to USART device instance
+ */
+void _usart_async_enable_tx_done_irq(struct _usart_async_device *const device);
+
+/**
+ * \brief Retrieve ordinal number of the given USART hardware instance
+ *
+ * \param[in] device The pointer to USART device instance
+ *
+ * \return The ordinal number of the given USART hardware instance
+ */
+uint8_t _usart_async_get_hardware_index(const struct _usart_async_device *const device);
+
+/**
+ * \brief Enable/disable USART interrupt
+ *
+ * param[in] device The pointer to USART device instance
+ * param[in] type The type of interrupt to disable/enable if applicable
+ * param[in] state Enable or disable
+ */
+void _usart_async_set_irq_state(struct _usart_async_device *const device, const enum _usart_async_callback_type type,
+                                const bool state);
+//@}
+
+#ifdef __cplusplus
+}
+#endif
+/**@}*/
+#endif /* _HPL_USART_ASYNC_H_INCLUDED */