1018 lines
27 KiB
C
1018 lines
27 KiB
C
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/**
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* \file
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*
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* \brief SAM Peripheral Access Controller Driver
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*
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* Copyright (C) 2012-2016 Atmel Corporation. All rights reserved.
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*
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* \asf_license_start
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*
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* \page License
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions are met:
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*
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* 1. Redistributions of source code must retain the above copyright notice,
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* this list of conditions and the following disclaimer.
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*
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* 2. Redistributions in binary form must reproduce the above copyright notice,
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* this list of conditions and the following disclaimer in the documentation
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* and/or other materials provided with the distribution.
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*
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* 3. The name of Atmel may not be used to endorse or promote products derived
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* from this software without specific prior written permission.
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*
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* 4. This software may only be redistributed and used in connection with an
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* Atmel microcontroller product.
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*
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* THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED
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* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
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* EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR
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* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*
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* \asf_license_stop
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*
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*/
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/*
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* Support and FAQ: visit <a href="http://www.atmel.com/design-support/">Atmel Support</a>
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*/
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#ifndef PAC_H_INCLUDED
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#define PAC_H_INCLUDED
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/**
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* \defgroup asfdoc_sam0_pac_group SAM Peripheral Access Controller (PAC) Driver
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*
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* This driver for Atmel® | SMART ARM®-based microcontroller provides
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* an interface for the locking and unlocking of peripheral registers within
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* the device. When a peripheral is locked, accidental writes to the peripheral
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* will be blocked and a CPU exception will be raised.
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*
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* The following peripherals are used by this module:
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* - PAC (Peripheral Access Controller)
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*
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* The following devices can use this module:
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* - Atmel | SMART SAM D20/D21
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* - Atmel | SMART SAM R21
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* - Atmel | SMART SAM D09/D10/D11
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* - Atmel | SMART SAM L21/L22
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* - Atmel | SMART SAM DA1
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* - Atmel | SMART SAM C20/C21
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* - Atmel | SMART SAM HA1
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*
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* The outline of this documentation is as follows:
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* - \ref asfdoc_sam0_pac_prerequisites
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* - \ref asfdoc_sam0_pac_module_overview
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* - \ref asfdoc_sam0_pac_special_considerations
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* - \ref asfdoc_sam0_pac_extra_info
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* - \ref asfdoc_sam0_pac_examples
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* - \ref asfdoc_sam0_pac_api_overview
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*
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*
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* \section asfdoc_sam0_pac_prerequisites Prerequisites
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*
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* There are no prerequisites for this module.
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*
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*
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* \section asfdoc_sam0_pac_module_overview Module Overview
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*
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* The SAM devices are fitted with a Peripheral Access Controller (PAC)
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* that can be used to lock and unlock write access to a peripheral's
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* registers (see \ref asfdoc_sam0_pac_non_write_protected). Locking a
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* peripheral minimizes the risk of unintended configuration changes to a
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* peripheral as a consequence of \ref asfdoc_sam0_pac_code_run_away
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* or use of a \ref asfdoc_sam0_pac_module_pointer.
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*
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* Physically, the PAC restricts write access through the AHB bus to registers
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* used by the peripheral, making the register non-writable. PAC locking of
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* modules should be implemented in configuration critical applications where
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* avoiding unintended peripheral configuration changes are to be regarded in
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* the highest of priorities.
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*
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* All interrupt must be disabled while a peripheral is unlocked to make sure
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* correct lock/unlock scheme is upheld.
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*
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* \subsection asfdoc_sam0_pac_locking_scheme Locking Scheme
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* The module has a built in safety feature requiring that an already locked
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* peripheral is not relocked, and that already unlocked peripherals are not
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* unlocked again. Attempting to unlock and already unlocked peripheral, or
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* attempting to lock a peripheral that is currently locked will generate a
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* CPU exception. This implies that the implementer must keep
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* strict control over the peripheral's lock-state before modifying them. With
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* this added safety, the probability of stopping runaway code increases as
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* the program pointer can be caught inside the exception handler, and necessary
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* countermeasures can be initiated. The implementer should also consider using
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* sanity checks after an unlock has been performed to further increase the
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* security.
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*
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* \subsection asfdoc_sam0_pac_correct_implementation Recommended Implementation
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* A recommended implementation of the PAC can be seen in
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* \ref asfdoc_sam0_pac_rec_imp_diagram "the figure below".
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*
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* \anchor asfdoc_sam0_pac_rec_imp_diagram
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* \dot
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* digraph correct {
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* subgraph cluster_a {
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* style="filled, dotted";
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* coler=lightgray;
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* init [label="Initialize Peripheral", shape=box];
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* lock [label="Lock peripheral", shape=box];
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* label="Initialization and code";
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* init -> lock;
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* }
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* subgraph cluster_b {
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* cli [label="Disable global interrupts", shape=box,
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* style=dotted];
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* unlock [label="Unlock peripheral", shape=box];
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* sanity [label="Sanity Check", shape=box, style=dotted];
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* modify [label="Modify peripheral", shape=box];
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* lock2 [label="Lock peripheral", shape=box];
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* sei [label="Enable global interrupts", shape=box
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* style=dotted];
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*
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* label="Peripheral Modification";
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* cli -> unlock;
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* unlock -> sanity
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* sanity -> modify;
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* modify -> lock2;
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* lock2 -> sei;
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* }
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* lock -> cli [label=
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* "Other initialization\n and enable interrupts if applicable"
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* , style=dotted];
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* }
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* \enddot
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*
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* \subsection asfdoc_sam0_pac_enabled_interrupt Why Disable Interrupts
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* Global interrupts must be disabled while a peripheral is unlocked as an
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* interrupt handler would not know the current state of the peripheral lock. If
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* the interrupt tries to alter the lock state, it can cause an exception as it
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* potentially tries to unlock an already unlocked peripheral. Reading current
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* lock state is to be avoided as it removes the security provided by the PAC
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* (\ref asfdoc_sam0_pac_check_lock).
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*
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* \note Global interrupts should also be disabled when a peripheral is unlocked
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* inside an interrupt handler.
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*
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* An example to illustrate the potential hazard of not disabling interrupts is
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* shown in \ref asfdoc_sam0_pac_int_hazard_diagram "the diagram below".
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*
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* \anchor asfdoc_sam0_pac_int_hazard_diagram
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* \dot
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||
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* digraph enabled_interrupt {
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||
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* subgraph cluster_0{
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* label="Main routine";
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* {node [style="filled", color=black, fillcolor=white]
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* init [label="Initialize and lock peripherals", shape=box];
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||
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* main_unlock [label="Unlock peripheral", shape=box,
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* fillcolor=green];
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* main_modify [label="Modify peripheral", shape=box];}
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* main_lock [label="Lock peripheral", shape=box];
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* init -> main_unlock [label="User code"];
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* main_unlock -> main_modify;
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* main_modify -> main_lock [style=dotted];
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* }
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* subgraph cluster_1 {
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* label="Interrupt handler";
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* int_unlock [label="Unlock peripheral", shape=box,
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* style=filled, fillcolor=red];
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* int_modify [label="Modify peripheral", shape=box];
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||
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* int_lock [label="Lock peripheral", shape=box];
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* int_unlock -> int_modify [style=dotted];
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* int_modify -> int_lock [style=dotted];
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* }
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* exception [label="Exception", shape=box, style=filled, fillcolor=red];
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* main_modify -> int_unlock [label=" Interrupt"];
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* int_unlock -> exception;
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* exception -> exception;
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* }
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* \enddot
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*
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* \subsection asfdoc_sam0_pac_code_run_away Run-away Code
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* Run-away code can be caused by the MCU being operated outside its
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* specification, faulty code, or EMI issues. If a runaway code occurs, it is
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* favorable to catch the issue as soon as possible. With a correct
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* implementation of the PAC, the runaway code can potentially be stopped.
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*
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* A graphical example showing how a PAC implementation will behave for
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* different circumstances of runaway code in shown in
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* \ref asfdoc_sam0_pac_code_runaway_diagram "the first" and
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* \ref asfdoc_sam0_pac_code_runaway_diagram2 "second figures below".
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||
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*
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||
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* \anchor asfdoc_sam0_pac_code_runaway_diagram
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* \dot
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||
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* digraph run_away {
|
||
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* subgraph cluster_away1{
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||
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* rankdir=TB;
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* color=white;
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||
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* runaway1 [label="Run-away code", shape=box];
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||
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* node [shape=plaintext];
|
||
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* program1 [label=<
|
||
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* <table>
|
||
|
* <tr>
|
||
|
* <td>PC#</td>
|
||
|
* <td>Code</td>
|
||
|
* </tr>
|
||
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* <tr>
|
||
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* <td>0x0020</td>
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||
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* <td>initialize peripheral</td>
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||
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* </tr>
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||
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* <tr>
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||
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* <td>0x0025</td>
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||
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* <td>lock peripheral</td>
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||
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* </tr>
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||
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* <tr>
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||
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* <td>...</td>
|
||
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* <td>...</td>
|
||
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* </tr>
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||
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* <tr>
|
||
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* <td>0x0080</td>
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||
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* <td>set sanity argument</td>
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||
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* </tr>
|
||
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* <tr>
|
||
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* <td port="f0" BGCOLOR="green">...</td>
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||
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* <td BGCOLOR="green">...</td>
|
||
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* </tr>
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||
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* <tr>
|
||
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* <td BGCOLOR="green">0x0115</td>
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||
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* <td BGCOLOR="green">disable interrupts</td>
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||
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* </tr>
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||
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* <tr>
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||
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* <td BGCOLOR="green">0x0120</td>
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||
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* <td BGCOLOR="green">unlock peripheral</td>
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||
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* </tr>
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||
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* <tr>
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||
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* <td BGCOLOR="red">0x0125</td>
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||
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* <td BGCOLOR="red">check sanity argument</td>
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||
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* </tr>
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||
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* <tr>
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||
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* <td>0x0130</td>
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||
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* <td>modify peripheral</td>
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||
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* </tr>
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||
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* <tr>
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||
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* <td>0x0140</td>
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||
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* <td>lock peripheral</td>
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||
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* </tr>
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||
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* <tr>
|
||
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* <td>0x0145</td>
|
||
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* <td>disable interrupts</td>
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||
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* </tr>
|
||
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* </table>
|
||
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* >]
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* runaway1 -> program1:f0;
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* label="1. Run-away code is caught in sanity check.\nA CPU exception is executed."
|
||
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* }
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||
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* subgraph cluster_away2{
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||
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* rankdir=TB;
|
||
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* runaway2 [label="Run-away code", shape=box];
|
||
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* color=white;
|
||
|
* node [shape=plaintext];
|
||
|
* program2 [label=<
|
||
|
* <table>
|
||
|
* <tr>
|
||
|
* <td>PC#</td>
|
||
|
* <td>Code</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>0x0020</td>
|
||
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* <td>initialize peripheral</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>0x0025</td>
|
||
|
* <td>lock peripheral</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>...</td>
|
||
|
* <td>...</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>0x0080</td>
|
||
|
* <td>set sanity argument</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td >...</td>
|
||
|
* <td >...</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td >0x0115</td>
|
||
|
* <td >disable interrupts</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td >0x0120</td>
|
||
|
* <td >unlock peripheral</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td >0x0125</td>
|
||
|
* <td >check sanity argument</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td port="f0" BGCOLOR="red">0x0130</td>
|
||
|
* <td BGCOLOR="red">modify peripheral</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>0x0140</td>
|
||
|
* <td>lock peripheral</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>0x0145</td>
|
||
|
* <td>disable interrupts</td>
|
||
|
* </tr>
|
||
|
* </table>
|
||
|
* >]
|
||
|
* runaway2 -> program2:f0;
|
||
|
* label="2. Run-away code is caught when modifying\nlocked peripheral. A CPU exception is executed."
|
||
|
* }
|
||
|
* }
|
||
|
* \enddot
|
||
|
*
|
||
|
* \anchor asfdoc_sam0_pac_code_runaway_diagram2
|
||
|
* \dot
|
||
|
* digraph run_away2 {
|
||
|
* subgraph cluster_away3{
|
||
|
* rankdir=TB;
|
||
|
* runaway3 [label="Run-away code", shape=box];
|
||
|
* color=white;
|
||
|
* node [shape=plaintext];
|
||
|
* program3 [label=<
|
||
|
* <table>
|
||
|
* <tr>
|
||
|
* <td>PC#</td>
|
||
|
* <td>Code</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>0x0020</td>
|
||
|
* <td>initialize peripheral</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>0x0025</td>
|
||
|
* <td>lock peripheral</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>...</td>
|
||
|
* <td>...</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>0x0080</td>
|
||
|
* <td>set sanity argument</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td >...</td>
|
||
|
* <td >...</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td >0x0115</td>
|
||
|
* <td >disable interrupts</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td >0x0120</td>
|
||
|
* <td >unlock peripheral</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td >0x0125</td>
|
||
|
* <td >check sanity argument</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td >0x0130</td>
|
||
|
* <td >modify peripheral</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td port="f0" BGCOLOR="red">0x0140</td>
|
||
|
* <td BGCOLOR="red">lock peripheral</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>0x0145</td>
|
||
|
* <td>disable interrupts</td>
|
||
|
* </tr>
|
||
|
* </table>
|
||
|
* >]
|
||
|
* runaway3 -> program3:f0;
|
||
|
* label="3. Run-away code is caught when locking\nlocked peripheral. A CPU exception is executed."
|
||
|
* }
|
||
|
* subgraph cluster_away4 {
|
||
|
* rankdir=TB;
|
||
|
* runaway4 [label="Run-away code", shape=box];
|
||
|
* color=white;
|
||
|
* node [shape=plaintext];
|
||
|
* program4 [label=<
|
||
|
* <table>
|
||
|
* <tr>
|
||
|
* <td>PC#</td>
|
||
|
* <td>Code</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>0x0020</td>
|
||
|
* <td>initialize peripheral</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>0x0025</td>
|
||
|
* <td>lock peripheral</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td port="f0" BGCOLOR="green">...</td>
|
||
|
* <td BGCOLOR="green">...</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td BGCOLOR="green">0x0080</td>
|
||
|
* <td BGCOLOR="green">set sanity argument</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td BGCOLOR="green">...</td>
|
||
|
* <td BGCOLOR="green">...</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td BGCOLOR="green">0x0115</td>
|
||
|
* <td BGCOLOR="green">disable interrupts</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td BGCOLOR="green">0x0120</td>
|
||
|
* <td BGCOLOR="green">unlock peripheral</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td BGCOLOR="green">0x0125</td>
|
||
|
* <td BGCOLOR="green">check sanity argument</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td BGCOLOR="green">0x0130</td>
|
||
|
* <td BGCOLOR="green">modify peripheral</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td BGCOLOR="green">0x0140</td>
|
||
|
* <td BGCOLOR="green">lock peripheral</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td BGCOLOR="green">0x0145</td>
|
||
|
* <td BGCOLOR="green">disable interrupts</td>
|
||
|
* </tr>
|
||
|
* </table>
|
||
|
* >]
|
||
|
* runaway4 -> program4:f0;
|
||
|
* label="4. Run-away code is not caught.\n "
|
||
|
* }
|
||
|
* }
|
||
|
* \enddot
|
||
|
*
|
||
|
* In the example, green indicates that the command is allowed, red indicates
|
||
|
* where the runaway code will be caught, and the arrow where the runaway
|
||
|
* code enters the application. In special circumstances, like example 4
|
||
|
* above, the runaway code will not be caught. However, the protection scheme
|
||
|
* will greatly enhance peripheral configuration security from being affected by
|
||
|
* runaway code.
|
||
|
*
|
||
|
* \subsubsection asfdoc_sam0_pac_bitwise_code Key-Argument
|
||
|
* To protect the module functions against runaway code themselves, a key
|
||
|
* is required as one of the input arguments. The key-argument will make sure
|
||
|
* that runaway code entering the function without a function call will be
|
||
|
* rejected before inflicting any damage. The argument is simply set to be
|
||
|
* the bitwise inverse of the module flag, i.e.
|
||
|
*
|
||
|
* \code
|
||
|
system_peripheral_<lock_state>(SYSTEM_PERIPHERAL_<module>,
|
||
|
~SYSTEM_PERIPHERAL_<module>);
|
||
|
\endcode
|
||
|
*
|
||
|
* Where the lock state can be either lock or unlock, and module refer to the
|
||
|
* peripheral that is to be locked/unlocked.
|
||
|
*
|
||
|
* \subsection asfdoc_sam0_pac_module_pointer Faulty Module Pointer
|
||
|
* The PAC also protects the application from user errors such as the use of
|
||
|
* incorrect module pointers in function arguments, given that the module is
|
||
|
* locked. It is therefore recommended that any unused peripheral is locked
|
||
|
* during application initialization.
|
||
|
*
|
||
|
* \subsection asfdoc_sam0_pac_no_inline Use of __no_inline
|
||
|
* Using the function attribute \c __no_inline will ensure that there will only be
|
||
|
* one copy of each functions in the PAC driver API in the application. This will
|
||
|
* lower the likelihood that runaway code will hit any of these functions.
|
||
|
*
|
||
|
* \subsection asfdoc_sam0_pac_module_overview_physical Physical Connection
|
||
|
*
|
||
|
* \ref asfdoc_sam0_pac_int_connections "The diagram below" shows how this
|
||
|
* module is interconnected within the device.
|
||
|
*
|
||
|
* \anchor asfdoc_sam0_pac_int_connections
|
||
|
* \dot
|
||
|
* digraph overview {
|
||
|
* nodesep = .05;
|
||
|
* rankdir=LR;
|
||
|
*
|
||
|
* ahb [label="Peripheral bus", shape=ellipse, style=filled, fillcolor=lightgray];
|
||
|
* pac [label="<f0>PAC|<f1>Lock|<f2>Open|<f3>Open",
|
||
|
* height=2.5, shape=record, width=.1];
|
||
|
* per1 [label="Peripheral1", shape=ellipse, style=filled, fillcolor=lightgray];
|
||
|
* per2 [label="Peripheral2", shape=ellipse, style=filled, fillcolor=lightgray];
|
||
|
* per3 [label="Peripheral3", shape=ellipse, style=filled, fillcolor=lightgray];
|
||
|
* edge [dir="both"];
|
||
|
* ahb -> pac:f1 [label="Read/Write"];
|
||
|
* ahb -> pac:f2 [label="Read/Write"];
|
||
|
* ahb -> pac:f3 [label="Read/Write"];
|
||
|
* edge [dir="back"];
|
||
|
* pac:f1 -> per1 [label="Read"];
|
||
|
* edge [dir="both"];
|
||
|
* pac:f2 -> per2 [label="Read/Write"];
|
||
|
* pac:f3 -> per3 [label="Read/Write"];
|
||
|
* {rank=same; per1 per2 per3 }
|
||
|
* }
|
||
|
* \enddot
|
||
|
*
|
||
|
*
|
||
|
* \section asfdoc_sam0_pac_special_considerations Special Considerations
|
||
|
*
|
||
|
* \subsection asfdoc_sam0_pac_non_write_protected Non-Writable Registers
|
||
|
* Not all registers in a given peripheral can be set non-writable. Which
|
||
|
* registers this applies to is showed in \ref asfdoc_sam0_pac_non_write_list
|
||
|
* and the peripheral's subsection "Register Access Protection" in the device
|
||
|
* datasheet.
|
||
|
*
|
||
|
* \subsection asfdoc_sam0_pac_check_lock Reading Lock State
|
||
|
* Reading the state of the peripheral lock is to be avoided as it greatly
|
||
|
* compromises the protection initially provided by the PAC. If a lock/unlock
|
||
|
* is implemented conditionally, there is a risk that eventual errors are not
|
||
|
* caught in the protection scheme. Examples indicating the issue are shown
|
||
|
* in \ref asfdoc_sam0_pac_lock_errors_diagram "the diagram below".
|
||
|
*
|
||
|
* \anchor asfdoc_sam0_pac_lock_errors_diagram
|
||
|
* \dot
|
||
|
* digraph read_lock {
|
||
|
* subgraph cluster_read1{
|
||
|
* rankdir=TB;
|
||
|
* color=white;
|
||
|
* runaway1 [label="Run-away code\nwith peripheral unlocked", shape=box];
|
||
|
* node [shape=plaintext];
|
||
|
* program1 [label=<
|
||
|
* <table>
|
||
|
* <tr>
|
||
|
* <td>PC#</td>
|
||
|
* <td>Code</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td port="f0" BGCOLOR="green">...</td>
|
||
|
* <td BGCOLOR="green">...</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td BGCOLOR="green">0x0100</td>
|
||
|
* <td BGCOLOR="green">check if locked</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td BGCOLOR="green">0x0102</td>
|
||
|
* <td BGCOLOR="green">disable interrupts</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td BGCOLOR="green">0x0105</td>
|
||
|
* <td BGCOLOR="green">unlock if locked</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td BGCOLOR="green">0x0110</td>
|
||
|
* <td BGCOLOR="green">check sanity</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td BGCOLOR="green">0x0115</td>
|
||
|
* <td BGCOLOR="green">modify peripheral</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td BGCOLOR="green">0x0120</td>
|
||
|
* <td BGCOLOR="green">lock if previously locked</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td BGCOLOR="green">0x0125</td>
|
||
|
* <td BGCOLOR="green">enable interrupts</td>
|
||
|
* </tr>
|
||
|
* </table>
|
||
|
* >]
|
||
|
* runaway1 -> program1:f0;
|
||
|
* label="1. Wrong implementation.\n "
|
||
|
* }
|
||
|
* subgraph cluster_read2{
|
||
|
* rankdir=TB;
|
||
|
* color=white;
|
||
|
* runaway2 [label="Run-away code\nwith peripheral unlocked", shape=box];
|
||
|
* node [shape=plaintext];
|
||
|
* program2 [label=<
|
||
|
* <table>
|
||
|
* <tr>
|
||
|
* <td>PC#</td>
|
||
|
* <td>Code</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td port="f0" BGCOLOR="green">...</td>
|
||
|
* <td BGCOLOR="green">...</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td BGCOLOR="green">0x0100</td>
|
||
|
* <td BGCOLOR="green">disable interrupts</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td BGCOLOR="red">0x0120</td>
|
||
|
* <td BGCOLOR="red">unlock peripheral</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>0x0125</td>
|
||
|
* <td>check sanity argument</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>0x0130</td>
|
||
|
* <td>modify peripheral</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>0x0140</td>
|
||
|
* <td>lock peripheral</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>0x0145</td>
|
||
|
* <td>disable interrupts</td>
|
||
|
* </tr>
|
||
|
* </table>
|
||
|
* >]
|
||
|
* runaway2 -> program2:f0;
|
||
|
*
|
||
|
* label="2. Correct implementation.\n "
|
||
|
* }
|
||
|
* }
|
||
|
* \enddot
|
||
|
*
|
||
|
* In the left figure above, one can see the runaway code continues as all
|
||
|
* illegal operations are conditional. On the right side figure, the runaway
|
||
|
* code is caught as it tries to unlock the peripheral.
|
||
|
*
|
||
|
* \section asfdoc_sam0_pac_extra_info Extra Information
|
||
|
*
|
||
|
* For extra information, see \ref asfdoc_sam0_pac_extra. This includes:
|
||
|
* - \ref asfdoc_sam0_pac_extra_acronyms
|
||
|
* - \ref asfdoc_sam0_pac_extra_dependencies
|
||
|
* - \ref asfdoc_sam0_pac_extra_errata
|
||
|
* - \ref asfdoc_sam0_pac_extra_history
|
||
|
*
|
||
|
*
|
||
|
* \section asfdoc_sam0_pac_examples Examples
|
||
|
*
|
||
|
* For a list of examples related to this driver, see
|
||
|
* \ref asfdoc_sam0_pac_exqsg.
|
||
|
*
|
||
|
*
|
||
|
* \section asfdoc_sam0_pac_api_overview API Overview
|
||
|
* @{
|
||
|
*/
|
||
|
|
||
|
#include <compiler.h>
|
||
|
#include <system.h>
|
||
|
|
||
|
#ifdef __cplusplus
|
||
|
extern "C" {
|
||
|
#endif
|
||
|
|
||
|
/**
|
||
|
* Retrieves the ID of a specified peripheral name, giving its peripheral bus
|
||
|
* location.
|
||
|
*
|
||
|
* \param[in] peripheral Name of the peripheral instance
|
||
|
*
|
||
|
* \returns Bus ID of the specified peripheral instance.
|
||
|
*/
|
||
|
#define SYSTEM_PERIPHERAL_ID(peripheral) ID_##peripheral
|
||
|
|
||
|
/** \name Peripheral Lock and Unlock
|
||
|
* @{
|
||
|
*/
|
||
|
__no_inline enum status_code system_peripheral_lock(
|
||
|
const uint32_t peripheral_id,
|
||
|
const uint32_t key);
|
||
|
|
||
|
__no_inline enum status_code system_peripheral_unlock(
|
||
|
const uint32_t peripheral_id,
|
||
|
const uint32_t key);
|
||
|
/** @} */
|
||
|
|
||
|
#if (SAML21) || (SAML22) || (SAMC20) || (SAMC21) || (SAMR30) || defined(__DOXYGEN__)
|
||
|
/** \name APIs available for SAM L21/L22/C20/C21.
|
||
|
* @{
|
||
|
*/
|
||
|
__no_inline enum status_code system_peripheral_lock_always(
|
||
|
const uint32_t peripheral_id,
|
||
|
const uint32_t key);
|
||
|
|
||
|
/**
|
||
|
* \brief Enable PAC interrupt.
|
||
|
*
|
||
|
* Enable PAC interrupt so can trigger execution on peripheral access error,
|
||
|
* see \ref SYSTEM_Handler().
|
||
|
*
|
||
|
*/
|
||
|
static inline void system_pac_enable_interrupt(void)
|
||
|
{
|
||
|
PAC->INTENSET.reg = PAC_INTENSET_ERR;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* \brief Disable PAC interrupt.
|
||
|
*
|
||
|
* Disable PAC interrupt on peripheral access error.
|
||
|
*
|
||
|
*/
|
||
|
static inline void system_pac_disable_interrupt(void)
|
||
|
{
|
||
|
PAC->INTENCLR.reg = PAC_INTENCLR_ERR;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* \brief Enable PAC event output.
|
||
|
*
|
||
|
* Enable PAC event output on peripheral access error.
|
||
|
*
|
||
|
*/
|
||
|
static inline void system_pac_enable_event(void)
|
||
|
{
|
||
|
PAC->EVCTRL.reg = PAC_EVCTRL_ERREO;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* \brief Disable PAC event output.
|
||
|
*
|
||
|
* Disable PAC event output on peripheral access error.
|
||
|
*
|
||
|
*/
|
||
|
static inline void system_pac_disable_event(void)
|
||
|
{
|
||
|
PAC->EVCTRL.reg &= (~PAC_EVCTRL_ERREO);
|
||
|
}
|
||
|
|
||
|
/** @} */
|
||
|
#endif
|
||
|
|
||
|
#ifdef __cplusplus
|
||
|
}
|
||
|
#endif
|
||
|
|
||
|
/** @} */
|
||
|
|
||
|
/**
|
||
|
* \page asfdoc_sam0_pac_extra Extra Information for PAC Driver
|
||
|
*
|
||
|
* \section asfdoc_sam0_pac_extra_acronyms Acronyms
|
||
|
* Below is a table listing the acronyms used in this module, along with their
|
||
|
* intended meanings.
|
||
|
*
|
||
|
* <table>
|
||
|
* <tr>
|
||
|
* <th>Acronym</td>
|
||
|
* <th>Description</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>AC</td>
|
||
|
* <td>Analog Comparator</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>ADC</td>
|
||
|
* <td>Analog-to-Digital Converter</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>EVSYS</td>
|
||
|
* <td>Event System</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>NMI</td>
|
||
|
* <td>Non-Maskable Interrupt</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>NVMCTRL</td>
|
||
|
* <td>Non-Volatile Memory Controller</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>PAC</td>
|
||
|
* <td>Peripheral Access Controller</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>PM</td>
|
||
|
* <td>Power Manager</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>RTC</td>
|
||
|
* <td>Real-Time Counter</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>SERCOM</td>
|
||
|
* <td>Serial Communication Interface</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>SYSCTRL</td>
|
||
|
* <td>System Controller</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>TC</td>
|
||
|
* <td>Timer/Counter</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>WDT</td>
|
||
|
* <td>Watch Dog Timer</td>
|
||
|
* </tr>
|
||
|
* </table>
|
||
|
*
|
||
|
*
|
||
|
* \section asfdoc_sam0_pac_extra_dependencies Dependencies
|
||
|
* This driver has the following dependencies:
|
||
|
*
|
||
|
* - None
|
||
|
*
|
||
|
*
|
||
|
* \section asfdoc_sam0_pac_extra_errata Errata
|
||
|
* There are no errata related to this driver.
|
||
|
*
|
||
|
*
|
||
|
* \section asfdoc_sam0_pac_extra_history Module History
|
||
|
* An overview of the module history is presented in the table below, with
|
||
|
* details on the enhancements and fixes made to the module since its first
|
||
|
* release. The current version of this corresponds to the newest version in
|
||
|
* the table.
|
||
|
*
|
||
|
* <table>
|
||
|
* <tr>
|
||
|
* <th>Changelog</th>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>Initial Release</td>
|
||
|
* </tr>
|
||
|
* </table>
|
||
|
*/
|
||
|
|
||
|
/**
|
||
|
* \page asfdoc_sam0_pac_exqsg Examples for PAC Driver
|
||
|
*
|
||
|
* This is a list of the available Quick Start guides (QSGs) and example
|
||
|
* applications for \ref asfdoc_sam0_pac_group. QSGs are simple examples with
|
||
|
* step-by-step instructions to configure and use this driver in a selection of
|
||
|
* use cases. Note that a QSG can be compiled as a standalone application or be
|
||
|
* added to the user application.
|
||
|
*
|
||
|
* - \subpage asfdoc_sam0_pac_basic_use_case
|
||
|
*/
|
||
|
|
||
|
/**
|
||
|
* \page asfdoc_sam0_pac_non_write_list List of Non-Write Protected Registers
|
||
|
*
|
||
|
* Look in device datasheet peripheral's subsection "Register Access
|
||
|
* Protection" to see which is actually available for your device.
|
||
|
* <table>
|
||
|
* <tr>
|
||
|
* <th>Module</th>
|
||
|
* <th>Non-write protected register</th>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>AC</td>
|
||
|
* <td>INTFLAG</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td></td>
|
||
|
* <td>STATUSA</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td></td>
|
||
|
* <td>STATUSB</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td></td>
|
||
|
* <td>STATUSC</td>
|
||
|
* </tr>
|
||
|
* <tr><td colspan="2"/></tr>
|
||
|
* <tr>
|
||
|
* <td>ADC</td>
|
||
|
* <td>INTFLAG</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td></td>
|
||
|
* <td>STATUS</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td></td>
|
||
|
* <td>RESULT</td>
|
||
|
* </tr>
|
||
|
* <tr><td colspan="2"/></tr>
|
||
|
* <tr>
|
||
|
* <td>EVSYS</td>
|
||
|
* <td>INTFLAG</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td></td>
|
||
|
* <td>CHSTATUS</td>
|
||
|
* </tr>
|
||
|
* <tr><td colspan="2"/></tr>
|
||
|
* <tr>
|
||
|
* <td>NVMCTRL</td>
|
||
|
* <td>INTFLAG</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td></td>
|
||
|
* <td>STATUS</td>
|
||
|
* </tr>
|
||
|
* <tr><td colspan="2"/></tr>
|
||
|
* <tr>
|
||
|
* <td>PM</td>
|
||
|
* <td>INTFLAG</td>
|
||
|
* </tr>
|
||
|
* <tr><td colspan="2"/></tr>
|
||
|
* <tr>
|
||
|
* <td>PORT</td>
|
||
|
* <td>N/A</td>
|
||
|
* </tr>
|
||
|
* <tr><td colspan="2"/></tr>
|
||
|
* <tr>
|
||
|
* <td>RTC</td>
|
||
|
* <td>INTFLAG</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td></td>
|
||
|
* <td>READREQ</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td></td>
|
||
|
* <td>STATUS</td>
|
||
|
* </tr>
|
||
|
* <tr><td colspan="2"/></tr>
|
||
|
* <tr>
|
||
|
* <td>SYSCTRL</td>
|
||
|
* <td>INTFLAG</td>
|
||
|
* </tr>
|
||
|
* <tr><td colspan="2"/></tr>
|
||
|
* <tr>
|
||
|
* <td>SERCOM</td>
|
||
|
* <td>INTFALG</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td></td>
|
||
|
* <td>STATUS</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td></td>
|
||
|
* <td>DATA</td>
|
||
|
* </tr>
|
||
|
* <tr><td colspan="2"/></tr>
|
||
|
* <tr>
|
||
|
* <td>TC</td>
|
||
|
* <td>INTFLAG</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td></td>
|
||
|
* <td>STATUS</td>
|
||
|
* </tr>
|
||
|
* <tr><td colspan="2"/></tr>
|
||
|
* <tr>
|
||
|
* <td>WDT</td>
|
||
|
* <td>INTFLAG</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td></td>
|
||
|
* <td>STATUS</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td></td>
|
||
|
* <td>(CLEAR)</td>
|
||
|
* </tr>
|
||
|
* </table>
|
||
|
*
|
||
|
* \page asfdoc_sam0_pac_document_revision_history Document Revision History
|
||
|
*
|
||
|
* <table>
|
||
|
* <tr>
|
||
|
* <th>Doc. Rev.</td>
|
||
|
* <th>Date</td>
|
||
|
* <th>Comments</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>42107F</td>
|
||
|
* <td>12/2015</td>
|
||
|
* <td>Added support for SAM L21/L22, SAM C20/C21, SAM D09, and SAM DA1</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>42107E</td>
|
||
|
* <td>12/2014</td>
|
||
|
* <td>Added support for SAM R21 and SAM D10/D11</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>42107D</td>
|
||
|
* <td>01/2014</td>
|
||
|
* <td>Added support for SAM D21</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>42107C</td>
|
||
|
* <td>10/2013</td>
|
||
|
* <td>Extended acronyms list</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>42107B</td>
|
||
|
* <td>06/2013</td>
|
||
|
* <td>Corrected documentation typos</td>
|
||
|
* </tr>
|
||
|
* <tr>
|
||
|
* <td>42107A</td>
|
||
|
* <td>06/2013</td>
|
||
|
* <td>Initial document release</td>
|
||
|
* </tr>
|
||
|
* </table>
|
||
|
*/
|
||
|
|
||
|
#endif /* PAC_H_INCLUDED */
|
||
|
|