nes-proj/cpu/cc2538/dev/gpio.c
Benoît Thébaudeau 5261bb861d cc2538: lpm: Fix RTIMER_NOW() upon wake-up
When returning from PM1/2, the sleep timer value (used by RTIMER_NOW()) is not
up-to-date until a positive edge on the 32-kHz clock has been detected after the
system clock restarted. To ensure an updated value is read, wait for a positive
transition on the 32-kHz clock by polling the SYS_CTRL_CLOCK_STA.SYNC_32K bit,
before reading the sleep timer value.

Because of this RTIMER_NOW() fixup, lpm_exit() has to be called at the very
beginning of ISRs waking up the SoC. This also ensures that all clocks and
timers are enabled at the correct frequency and updated before using them
following wake-up.

Without this fix, etimers could sometimes (randomly, depending on timings)
become ultra slow (observed from 10x to 40x slower than normal) if the system
exited PM1/2 very often. This issue occurred more often with PM1.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
2013-12-05 20:23:29 +01:00

152 lines
4.6 KiB
C

/*
* Copyright (c) 2012, Texas Instruments Incorporated - http://www.ti.com/
* 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. Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/**
* \addtogroup cc2538-gpio
* @{
*
* \file
* Implementation of the cc2538 GPIO controller
*/
#include "contiki.h"
#include "sys/energest.h"
#include "dev/leds.h"
#include "dev/gpio.h"
#include "dev/nvic.h"
#include "reg.h"
#include "lpm.h"
#include <string.h>
/**
* \brief Pointer to a function to be called when a GPIO interrupt is detected.
* Callbacks for Port A, Pins[0:7] are stored in positions [0:7] of this
* buffer, Port B callbacks in [8:15] and so on
*/
static gpio_callback_t gpio_callbacks[32];
/*---------------------------------------------------------------------------*/
void
gpio_register_callback(gpio_callback_t f, uint8_t port, uint8_t pin)
{
gpio_callbacks[(port << 3) + pin] = f;
}
/*---------------------------------------------------------------------------*/
/** \brief Run through all registered GPIO callbacks and invoke those
* associated with the \a port and the pins specified by \a mask
* \param mask Search callbacks associated with pins specified by this mask
* \param port Search callbacks associated with this port. Here, port is
* specified as a number between 0 and 3. Port A: 0, Port B: 1 etc */
void
notify(uint8_t mask, uint8_t port)
{
uint8_t i;
gpio_callback_t *f = &gpio_callbacks[port << 3];
for(i = 0; i < 8; i++) {
if(mask & (1 << i)) {
if((*f) != NULL) {
(*f)(port, i);
}
}
f++;
}
}
/*---------------------------------------------------------------------------*/
/** \brief Interrupt service routine for Port A */
void
gpio_port_a_isr()
{
lpm_exit();
ENERGEST_ON(ENERGEST_TYPE_IRQ);
notify(REG(GPIO_A_BASE | GPIO_MIS), GPIO_A_NUM);
GPIO_CLEAR_INTERRUPT(GPIO_A_BASE, 0xFF);
GPIO_CLEAR_POWER_UP_INTERRUPT(GPIO_A_NUM, 0xFF);
ENERGEST_OFF(ENERGEST_TYPE_IRQ);
}
/*---------------------------------------------------------------------------*/
/** \brief Interrupt service routine for Port B */
void
gpio_port_b_isr()
{
lpm_exit();
ENERGEST_ON(ENERGEST_TYPE_IRQ);
notify(REG(GPIO_B_BASE | GPIO_MIS), GPIO_B_NUM);
GPIO_CLEAR_INTERRUPT(GPIO_B_BASE, 0xFF);
GPIO_CLEAR_POWER_UP_INTERRUPT(GPIO_B_NUM, 0xFF);
ENERGEST_OFF(ENERGEST_TYPE_IRQ);
}
/*---------------------------------------------------------------------------*/
/** \brief Interrupt service routine for Port C */
void
gpio_port_c_isr()
{
lpm_exit();
ENERGEST_ON(ENERGEST_TYPE_IRQ);
notify(REG(GPIO_C_BASE | GPIO_MIS), GPIO_C_NUM);
GPIO_CLEAR_INTERRUPT(GPIO_C_BASE, 0xFF);
GPIO_CLEAR_POWER_UP_INTERRUPT(GPIO_C_NUM, 0xFF);
ENERGEST_OFF(ENERGEST_TYPE_IRQ);
}
/*---------------------------------------------------------------------------*/
/** \brief Interrupt service routine for Port D */
void
gpio_port_d_isr()
{
lpm_exit();
ENERGEST_ON(ENERGEST_TYPE_IRQ);
notify(REG(GPIO_D_BASE | GPIO_MIS), GPIO_D_NUM);
GPIO_CLEAR_INTERRUPT(GPIO_D_BASE, 0xFF);
GPIO_CLEAR_POWER_UP_INTERRUPT(GPIO_D_NUM, 0xFF);
ENERGEST_OFF(ENERGEST_TYPE_IRQ);
}
/*---------------------------------------------------------------------------*/
void
gpio_init()
{
memset(gpio_callbacks, 0, sizeof(gpio_callbacks));
}
/** @} */