Move to ASF4 and introduce SAMD51 support. (#258)3.0.0-alpha.0

* atmel-samd: Remove ASF3. This will break builds.

* atmel-samd: Add ASF4 for the SAMD21 and SAMD51.

* Introduce the supervisor concept to facilitate porting.

The supervisor is the code which runs individual MicroPython VMs. By
splitting it out we make it more consistent and easier to find.

This also adds very basic SAMD21 and SAMD51 support using the
supervisor. Only the REPL currently works.

This begins the work for #178.

1 files changed, 137 insertions, 0 deletions

diff --git a/atmel-samd/asf4/samd21/hal/include/hal_atomic.h b/atmel-samd/asf4/samd21/hal/include/hal_atomic.h
new file mode 100644
index 000000000..8a51b2a96
--- /dev/null
+++ b/atmel-samd/asf4/samd21/hal/include/hal_atomic.h
@@ -0,0 +1,137 @@
+/**
+ * \file
+ *
+ * \brief Critical sections related functionality declaration.
+ *
+ * Copyright (C) 2014 Atmel Corporation. All rights reserved.
+ *
+ * \asf_license_start
+ *
+ * \page License
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * 3. The name of Atmel may not be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * 4. This software may only be redistributed and used in connection with an
+ *    Atmel microcontroller product.
+ *
+ * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
+ * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ * \asf_license_stop
+ *
+ */
+
+#ifndef _HAL_ATOMIC_H_INCLUDED
+#define _HAL_ATOMIC_H_INCLUDED
+
+#include <compiler.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * \addtogroup doc_driver_hal_helper_atomic
+ *
+ *@{
+ */
+
+/**
+ * \brief Type for the register holding global interrupt enable flag
+ */
+typedef uint32_t hal_atomic_t;
+
+/**
+ * \brief Helper macro for entering critical sections
+ *
+ * This macro is recommended to be used instead of a direct call
+ * hal_enterCritical() function to enter critical
+ * sections. No semicolon is required after the macro.
+ *
+ * \section atomic_usage Usage Example
+ * \code
+ * CRITICAL_SECTION_ENTER()
+ * Critical code
+ * CRITICAL_SECTION_LEAVE()
+ * \endcode
+ */
+#define CRITICAL_SECTION_ENTER()                                                                                       \
+	{                                                                                                                  \
+		volatile hal_atomic_t __atomic;                                                                                \
+		atomic_enter_critical(&__atomic);
+
+/**
+ * \brief Helper macro for leaving critical sections
+ *
+ * This macro is recommended to be used instead of a direct call
+ * hal_leaveCritical() function to leave critical
+ * sections. No semicolon is required after the macro.
+ *
+ * \section atomic_usage Usage Example
+ * \code
+ * CRITICAL_SECTION_ENTER()
+ * Some critical code
+ * CRITICAL_SECTION_LEAVE()
+ * \endcode
+ */
+#define CRITICAL_SECTION_LEAVE()                                                                                       \
+	atomic_leave_critical(&__atomic);                                                                                  \
+	}
+
+/**
+ * \brief Disable interrupts, enter critical section
+ *
+ * Disables global interrupts. Supports nested critical sections,
+ * so that global interrupts are only re-enabled
+ * upon leaving the outermost nested critical section.
+ *
+ * \param[out] atomic The pointer to a variable to store the value of global
+ * interrupt enable flag
+ */
+void atomic_enter_critical(hal_atomic_t volatile *atomic);
+
+/**
+ * \brief Exit atomic section
+ *
+ * Enables global interrupts. Supports nested critical sections,
+ * so that global interrupts are only re-enabled
+ * upon leaving the outermost nested critical section.
+ *
+ * \param[in] atomic The pointer to a variable, which stores the latest stored
+ * value of the global interrupt enable flag
+ */
+void atomic_leave_critical(hal_atomic_t volatile *atomic);
+
+/**
+ * \brief Retrieve the current driver version
+ *
+ * \return Current driver version.
+ */
+uint32_t atomic_get_version(void);
+/**@}*/
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _HAL_ATOMIC_H_INCLUDED */