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Diffstat (limited to 'firmwares/wifishield/wifi_dnld/src/SOFTWARE_FRAMEWORK/DRIVERS/INTC/intc.c')
| -rw-r--r-- | firmwares/wifishield/wifi_dnld/src/SOFTWARE_FRAMEWORK/DRIVERS/INTC/intc.c | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/firmwares/wifishield/wifi_dnld/src/SOFTWARE_FRAMEWORK/DRIVERS/INTC/intc.c b/firmwares/wifishield/wifi_dnld/src/SOFTWARE_FRAMEWORK/DRIVERS/INTC/intc.c new file mode 100644 index 0000000..84d498d --- /dev/null +++ b/firmwares/wifishield/wifi_dnld/src/SOFTWARE_FRAMEWORK/DRIVERS/INTC/intc.c @@ -0,0 +1,214 @@ +/* This source file is part of the ATMEL AVR-UC3-SoftwareFramework-1.7.0 Release */ + +/*This file is prepared for Doxygen automatic documentation generation.*/ +/*! \file ********************************************************************* + * + * \brief INTC driver for AVR32 UC3. + * + * AVR32 Interrupt Controller driver module. + * + * - Compiler: IAR EWAVR32 and GNU GCC for AVR32 + * - Supported devices: All AVR32 devices with an INTC module can be used. + * - AppNote: + * + * \author Atmel Corporation: http://www.atmel.com \n + * Support and FAQ: http://support.atmel.no/ + * + ******************************************************************************/ + +/* Copyright (c) 2009 Atmel Corporation. All rights reserved. + * + * 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 + * AVR 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 + * + */ + +#include <avr32/io.h> +#include "compiler.h" +#include "preprocessor.h" +#include "intc.h" + +// define _evba from exception.S +extern void _evba; + +//! Values to store in the interrupt priority registers for the various interrupt priority levels. +extern const unsigned int ipr_val[AVR32_INTC_NUM_INT_LEVELS]; + +//! Creates a table of interrupt line handlers per interrupt group in order to optimize RAM space. +//! Each line handler table contains a set of pointers to interrupt handlers. +#if (defined __GNUC__) +#define DECL_INT_LINE_HANDLER_TABLE(GRP, unused) \ +static volatile __int_handler _int_line_handler_table_##GRP[Max(AVR32_INTC_NUM_IRQS_PER_GRP##GRP, 1)]; +#elif (defined __ICCAVR32__) +#define DECL_INT_LINE_HANDLER_TABLE(GRP, unused) \ +static volatile __no_init __int_handler _int_line_handler_table_##GRP[Max(AVR32_INTC_NUM_IRQS_PER_GRP##GRP, 1)]; +#endif +MREPEAT(AVR32_INTC_NUM_INT_GRPS, DECL_INT_LINE_HANDLER_TABLE, ~); +#undef DECL_INT_LINE_HANDLER_TABLE + +//! Table containing for each interrupt group the number of interrupt request +//! lines and a pointer to the table of interrupt line handlers. +static const struct +{ + unsigned int num_irqs; + volatile __int_handler *_int_line_handler_table; +} _int_handler_table[AVR32_INTC_NUM_INT_GRPS] = +{ +#define INSERT_INT_LINE_HANDLER_TABLE(GRP, unused) \ + {AVR32_INTC_NUM_IRQS_PER_GRP##GRP, _int_line_handler_table_##GRP}, + MREPEAT(AVR32_INTC_NUM_INT_GRPS, INSERT_INT_LINE_HANDLER_TABLE, ~) +#undef INSERT_INT_LINE_HANDLER_TABLE +}; + + +/*! \brief Default interrupt handler. + * + * \note Taken and adapted from Newlib. + */ +#if (defined __GNUC__) +__attribute__((__interrupt__)) +#elif (defined __ICCAVR32__) +__interrupt +#endif +static void _unhandled_interrupt(void) +{ + // Catch unregistered interrupts. + while (TRUE); +} + + +/*! \brief Gets the interrupt handler of the current event at the \a int_level + * interrupt priority level (called from exception.S). + * + * \param int_level Interrupt priority level to handle. + * + * \return Interrupt handler to execute. + * + * \note Taken and adapted from Newlib. + */ +__int_handler _get_interrupt_handler(unsigned int int_level) +{ + // ICR3 is mapped first, ICR0 last. + // Code in exception.S puts int_level in R12 which is used by AVR32-GCC to + // pass a single argument to a function. + unsigned int int_grp = AVR32_INTC.icr[AVR32_INTC_INT3 - int_level]; + unsigned int int_req = AVR32_INTC.irr[int_grp]; + + // As an interrupt may disappear while it is being fetched by the CPU + // (spurious interrupt caused by a delayed response from an MCU peripheral to + // an interrupt flag clear or interrupt disable instruction), check if there + // are remaining interrupt lines to process. + // If a spurious interrupt occurs, the status register (SR) contains an + // execution mode and interrupt level masks corresponding to a level 0 + // interrupt, whatever the interrupt priority level causing the spurious + // event. This behavior has been chosen because a spurious interrupt has not + // to be a priority one and because it may not cause any trouble to other + // interrupts. + // However, these spurious interrupts place the hardware in an unstable state + // and could give problems in other/future versions of the CPU, so the + // software has to be written so that they never occur. The only safe way of + // achieving this is to always clear or disable peripheral interrupts with the + // following sequence: + // 1: Mask the interrupt in the CPU by setting GM (or IxM) in SR. + // 2: Perform the bus access to the peripheral register that clears or + // disables the interrupt. + // 3: Wait until the interrupt has actually been cleared or disabled by the + // peripheral. This is usually performed by reading from a register in the + // same peripheral (it DOES NOT have to be the same register that was + // accessed in step 2, but it MUST be in the same peripheral), what takes + // bus system latencies into account, but peripheral internal latencies + // (generally 0 cycle) also have to be considered. + // 4: Unmask the interrupt in the CPU by clearing GM (or IxM) in SR. + // Note that steps 1 and 4 are useless inside interrupt handlers as the + // corresponding interrupt level is automatically masked by IxM (unless IxM is + // explicitly cleared by the software). + // + // Get the right IRQ handler. + // + // If several interrupt lines are active in the group, the interrupt line with + // the highest number is selected. This is to be coherent with the + // prioritization of interrupt groups performed by the hardware interrupt + // controller. + // + // If no handler has been registered for the pending interrupt, + // _unhandled_interrupt will be selected thanks to the initialization of + // _int_line_handler_table_x by INTC_init_interrupts. + // + // exception.S will provide the interrupt handler with a clean interrupt stack + // frame, with nothing more pushed onto the stack. The interrupt handler must + // manage the `rete' instruction, what can be done thanks to pure assembly, + // inline assembly or the `__attribute__((__interrupt__))' C function + // attribute. + return (int_req) ? _int_handler_table[int_grp]._int_line_handler_table[32 - clz(int_req) - 1] : NULL; +} + +//! Init EVBA address. This sequence might also be done in the UTILS/STARTUP/GCC/crt0.S +static __inline__ void INTC_init_evba(void) +{ + Set_system_register(AVR32_EVBA, (int)&_evba ); +} + +void INTC_init_interrupts(void) +{ + unsigned int int_grp, int_req; + + INTC_init_evba(); + + // For all interrupt groups, + for (int_grp = 0; int_grp < AVR32_INTC_NUM_INT_GRPS; int_grp++) + { + // For all interrupt request lines of each group, + for (int_req = 0; int_req < _int_handler_table[int_grp].num_irqs; int_req++) + { + // Assign _unhandled_interrupt as default interrupt handler. + _int_handler_table[int_grp]._int_line_handler_table[int_req] = &_unhandled_interrupt; + } + + // Set the interrupt group priority register to its default value. + // By default, all interrupt groups are linked to the interrupt priority + // level 0 and to the interrupt vector _int0. + AVR32_INTC.ipr[int_grp] = ipr_val[AVR32_INTC_INT0]; + } +} + + +void INTC_register_interrupt(__int_handler handler, unsigned int irq, unsigned int int_level) +{ + // Determine the group of the IRQ. + unsigned int int_grp = irq / AVR32_INTC_MAX_NUM_IRQS_PER_GRP; + + // Store in _int_line_handler_table_x the pointer to the interrupt handler, so + // that _get_interrupt_handler can retrieve it when the interrupt is vectored. + _int_handler_table[int_grp]._int_line_handler_table[irq % AVR32_INTC_MAX_NUM_IRQS_PER_GRP] = handler; + + // Program the corresponding IPRX register to set the interrupt priority level + // and the interrupt vector offset that will be fetched by the core interrupt + // system. + // NOTE: The _intx functions are intermediate assembly functions between the + // core interrupt system and the user interrupt handler. + AVR32_INTC.ipr[int_grp] = ipr_val[int_level & (AVR32_INTC_IPR_INTLEVEL_MASK >> AVR32_INTC_IPR_INTLEVEL_OFFSET)]; +} |