osd-contiki/cpu/cc2538/dev/cc2538-rf.c

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/*
* 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
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* 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
* 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.
*/
/**
* \addtogroup cc2538-rf
* @{
*
* \file
* Implementation of the cc2538 RF driver
*/
#include "contiki.h"
#include "dev/radio.h"
#include "sys/clock.h"
#include "sys/rtimer.h"
#include "net/packetbuf.h"
#include "net/rime/rimestats.h"
#include "net/rime/rimeaddr.h"
#include "net/netstack.h"
#include "sys/energest.h"
#include "dev/cc2538-rf.h"
#include "dev/rfcore.h"
#include "dev/sys-ctrl.h"
#include "dev/udma.h"
#include "reg.h"
#include <string.h>
/*---------------------------------------------------------------------------*/
#define CHECKSUM_LEN 2
/* uDMA channel control persistent flags */
#define UDMA_TX_FLAGS (UDMA_CHCTL_ARBSIZE_128 | UDMA_CHCTL_XFERMODE_AUTO \
| UDMA_CHCTL_SRCSIZE_8 | UDMA_CHCTL_DSTSIZE_8 \
| UDMA_CHCTL_SRCINC_8 | UDMA_CHCTL_DSTINC_NONE)
#define UDMA_RX_FLAGS (UDMA_CHCTL_ARBSIZE_128 | UDMA_CHCTL_XFERMODE_AUTO \
| UDMA_CHCTL_SRCSIZE_8 | UDMA_CHCTL_DSTSIZE_8 \
| UDMA_CHCTL_SRCINC_NONE | UDMA_CHCTL_DSTINC_8)
/*
* uDMA transfer threshold. DMA will only be used to read an incoming frame
* if its size is above this threshold
*/
#define UDMA_RX_SIZE_THRESHOLD 3
/*---------------------------------------------------------------------------*/
#include <stdio.h>
#define DEBUG 0
#if DEBUG
#define PRINTF(...) printf(__VA_ARGS__)
#else
#define PRINTF(...)
#endif
/*---------------------------------------------------------------------------*/
/* Local RF Flags */
#define RX_ACTIVE 0x80
#define RF_MUST_RESET 0x40
#define WAS_OFF 0x10
#define RF_ON 0x01
/* Bit Masks for the last byte in the RX FIFO */
#define CRC_BIT_MASK 0x80
#define LQI_BIT_MASK 0x7F
/* RSSI Offset */
#define RSSI_OFFSET 73
/* 192 usec off -> on interval (RX Callib -> SFD Wait). We wait a bit more */
#define ONOFF_TIME RTIMER_ARCH_SECOND / 3125
/*---------------------------------------------------------------------------*/
/* Sniffer configuration */
#ifndef CC2538_RF_CONF_SNIFFER_USB
#define CC2538_RF_CONF_SNIFFER_USB 0
#endif
#if CC2538_RF_CONF_SNIFFER
static const uint8_t magic[] = { 0x53, 0x6E, 0x69, 0x66 }; /** Snif */
#if CC2538_RF_CONF_SNIFFER_USB
#include "usb/usb-serial.h"
#define write_byte(b) usb_serial_writeb(b)
#define flush() usb_serial_flush()
#else
#include "dev/uart.h"
#define write_byte(b) uart_write_byte(b)
#define flush()
#endif
#else /* CC2538_RF_CONF_SNIFFER */
#define write_byte(b)
#define flush()
#endif /* CC2538_RF_CONF_SNIFFER */
/*---------------------------------------------------------------------------*/
#ifdef CC2538_RF_CONF_AUTOACK
#define CC2538_RF_AUTOACK CC2538_RF_CONF_AUTOACK
#else
#define CC2538_RF_AUTOACK 1
#endif
/*---------------------------------------------------------------------------*/
static uint8_t rf_flags;
static int on(void);
static int off(void);
/*---------------------------------------------------------------------------*/
PROCESS(cc2538_rf_process, "cc2538 RF driver");
/*---------------------------------------------------------------------------*/
uint8_t
cc2538_rf_channel_get()
{
uint8_t chan = REG(RFCORE_XREG_FREQCTRL) & RFCORE_XREG_FREQCTRL_FREQ;
return ((chan - CC2538_RF_CHANNEL_MIN) / CC2538_RF_CHANNEL_SPACING
+ CC2538_RF_CHANNEL_MIN);
}
/*---------------------------------------------------------------------------*/
int8_t
cc2538_rf_channel_set(uint8_t channel)
{
PRINTF("RF: Set Channel\n");
if((channel < CC2538_RF_CHANNEL_MIN) || (channel > CC2538_RF_CHANNEL_MAX)) {
return -1;
}
/* Changes to FREQCTRL take effect after the next recalibration */
off();
REG(RFCORE_XREG_FREQCTRL) = (CC2538_RF_CHANNEL_MIN
+ (channel - CC2538_RF_CHANNEL_MIN) * CC2538_RF_CHANNEL_SPACING);
on();
return (int8_t) channel;
}
/*---------------------------------------------------------------------------*/
uint8_t
cc2538_rf_power_set(uint8_t new_power)
{
PRINTF("RF: Set Power\n");
REG(RFCORE_XREG_TXPOWER) = new_power;
return (REG(RFCORE_XREG_TXPOWER) & 0xFF);
}
/*---------------------------------------------------------------------------*/
/* ToDo: Check once we have info on the... infopage */
void
cc2538_rf_set_addr(uint16_t pan)
{
#if RIMEADDR_SIZE==8
/* EXT_ADDR[7:0] is ignored when using short addresses */
int i;
for(i = (RIMEADDR_SIZE - 1); i >= 0; --i) {
((uint32_t *)RFCORE_FFSM_EXT_ADDR0)[i] =
rimeaddr_node_addr.u8[RIMEADDR_SIZE - 1 - i];
}
#endif
REG(RFCORE_FFSM_PAN_ID0) = pan & 0xFF;
REG(RFCORE_FFSM_PAN_ID1) = pan >> 8;
REG(RFCORE_FFSM_SHORT_ADDR0) = rimeaddr_node_addr.u8[RIMEADDR_SIZE - 1];
REG(RFCORE_FFSM_SHORT_ADDR1) = rimeaddr_node_addr.u8[RIMEADDR_SIZE - 2];
}
/*---------------------------------------------------------------------------*/
/* Netstack API radio driver functions */
/*---------------------------------------------------------------------------*/
static int
channel_clear(void)
{
int cca;
PRINTF("RF: CCA\n");
/* If we are off, turn on first */
if((REG(RFCORE_XREG_FSMSTAT0) & RFCORE_XREG_FSMSTAT0_FSM_FFCTRL_STATE) == 0) {
rf_flags |= WAS_OFF;
on();
}
/* Wait on RSSI_VALID */
while((REG(RFCORE_XREG_RSSISTAT) & RFCORE_XREG_RSSISTAT_RSSI_VALID) == 0);
if(REG(RFCORE_XREG_FSMSTAT1) & RFCORE_XREG_FSMSTAT1_CCA) {
cca = CC2538_RF_CCA_CLEAR;
} else {
cca = CC2538_RF_CCA_BUSY;
}
/* If we were off, turn back off */
if((rf_flags & WAS_OFF) == WAS_OFF) {
rf_flags &= ~WAS_OFF;
off();
}
return cca;
}
/*---------------------------------------------------------------------------*/
static int
on(void)
{
PRINTF("RF: On\n");
if(!(rf_flags & RX_ACTIVE)) {
CC2538_RF_CSP_ISFLUSHRX();
CC2538_RF_CSP_ISRXON();
rf_flags |= RX_ACTIVE;
}
ENERGEST_ON(ENERGEST_TYPE_LISTEN);
return 1;
}
/*---------------------------------------------------------------------------*/
static int
off(void)
{
PRINTF("RF: Off\n");
/* Wait for ongoing TX to complete (e.g. this could be an outgoing ACK) */
while(REG(RFCORE_XREG_FSMSTAT1) & RFCORE_XREG_FSMSTAT1_TX_ACTIVE);
CC2538_RF_CSP_ISFLUSHRX();
/* Don't turn off if we are off as this will trigger a Strobe Error */
if(REG(RFCORE_XREG_RXENABLE) != 0) {
CC2538_RF_CSP_ISRFOFF();
}
rf_flags &= ~RX_ACTIVE;
ENERGEST_OFF(ENERGEST_TYPE_LISTEN);
return 1;
}
/*---------------------------------------------------------------------------*/
static int
init(void)
{
PRINTF("RF: Init\n");
if(rf_flags & RF_ON) {
return 0;
}
/* Enable clock for the RF Core while Running, in Sleep and Deep Sleep */
REG(SYS_CTRL_RCGCRFC) = 1;
REG(SYS_CTRL_SCGCRFC) = 1;
REG(SYS_CTRL_DCGCRFC) = 1;
REG(RFCORE_XREG_CCACTRL0) = CC2538_RF_CCA_THRES_USER_GUIDE;
/*
* Changes from default values
* See User Guide, section "Register Settings Update"
*/
REG(RFCORE_XREG_TXFILTCFG) = 0x09; /** TX anti-aliasing filter bandwidth */
REG(RFCORE_XREG_AGCCTRL1) = 0x15; /** AGC target value */
REG(ANA_REGS_IVCTRL) = 0x0B; /** Bias currents */
/*
* Defaults:
* Auto CRC; Append RSSI, CRC-OK and Corr. Val.; CRC calculation;
* RX and TX modes with FIFOs
*/
REG(RFCORE_XREG_FRMCTRL0) = RFCORE_XREG_FRMCTRL0_AUTOCRC;
#if CC2538_RF_AUTOACK
REG(RFCORE_XREG_FRMCTRL0) |= RFCORE_XREG_FRMCTRL0_AUTOACK;
#endif
/* If we are a sniffer, turn off frame filtering */
#if CC2538_RF_CONF_SNIFFER
REG(RFCORE_XREG_FRMFILT0) &= ~RFCORE_XREG_FRMFILT0_FRAME_FILTER_EN;
#endif
/* Disable source address matching and autopend */
REG(RFCORE_XREG_SRCMATCH) = 0;
/* MAX FIFOP threshold */
REG(RFCORE_XREG_FIFOPCTRL) = CC2538_RF_MAX_PACKET_LEN;
cc2538_rf_power_set(CC2538_RF_TX_POWER);
cc2538_rf_channel_set(CC2538_RF_CHANNEL);
/* Acknowledge RF interrupts, FIFOP only */
REG(RFCORE_XREG_RFIRQM0) |= RFCORE_XREG_RFIRQM0_FIFOP;
nvic_interrupt_enable(NVIC_INT_RF_RXTX);
/* Acknowledge all RF Error interrupts */
REG(RFCORE_XREG_RFERRM) = RFCORE_XREG_RFERRM_RFERRM;
nvic_interrupt_enable(NVIC_INT_RF_ERR);
if(CC2538_RF_CONF_TX_USE_DMA) {
/* Disable peripheral triggers for the channel */
udma_channel_mask_set(CC2538_RF_CONF_TX_DMA_CHAN);
/*
* Set the channel's DST. SRC can not be set yet since it will change for
* each transfer
*/
udma_set_channel_dst(CC2538_RF_CONF_TX_DMA_CHAN, RFCORE_SFR_RFDATA);
}
if(CC2538_RF_CONF_RX_USE_DMA) {
/* Disable peripheral triggers for the channel */
udma_channel_mask_set(CC2538_RF_CONF_RX_DMA_CHAN);
/*
* Set the channel's SRC. DST can not be set yet since it will change for
* each transfer
*/
udma_set_channel_src(CC2538_RF_CONF_RX_DMA_CHAN, RFCORE_SFR_RFDATA);
}
process_start(&cc2538_rf_process, NULL);
rf_flags |= RF_ON;
ENERGEST_ON(ENERGEST_TYPE_LISTEN);
return 1;
}
/*---------------------------------------------------------------------------*/
static int
prepare(const void *payload, unsigned short payload_len)
{
uint8_t i;
PRINTF("RF: Prepare 0x%02x bytes\n", payload_len + CHECKSUM_LEN);
/*
* When we transmit in very quick bursts, make sure previous transmission
* is not still in progress before re-writing to the TX FIFO
*/
while(REG(RFCORE_XREG_FSMSTAT1) & RFCORE_XREG_FSMSTAT1_TX_ACTIVE);
if((rf_flags & RX_ACTIVE) == 0) {
on();
}
CC2538_RF_CSP_ISFLUSHTX();
PRINTF("RF: data = ");
/* Send the phy length byte first */
REG(RFCORE_SFR_RFDATA) = payload_len + CHECKSUM_LEN;
if(CC2538_RF_CONF_TX_USE_DMA) {
PRINTF("<uDMA payload>");
/* Set the transfer source's end address */
udma_set_channel_src(CC2538_RF_CONF_TX_DMA_CHAN,
(uint32_t)(payload) + payload_len - 1);
/* Configure the control word */
udma_set_channel_control_word(CC2538_RF_CONF_TX_DMA_CHAN,
UDMA_TX_FLAGS | udma_xfer_size(payload_len));
/* Enabled the RF TX uDMA channel */
udma_channel_enable(CC2538_RF_CONF_TX_DMA_CHAN);
/* Trigger the uDMA transfer */
udma_channel_sw_request(CC2538_RF_CONF_TX_DMA_CHAN);
/*
* No need to wait for this to end. Even if transmit() gets called
* immediately, the uDMA controller will stream the frame to the TX FIFO
* faster than transmit() can empty it
*/
} else {
for(i = 0; i < payload_len; i++) {
REG(RFCORE_SFR_RFDATA) = ((unsigned char *)(payload))[i];
PRINTF("%02x", ((unsigned char *)(payload))[i]);
}
}
PRINTF("\n");
return 0;
}
/*---------------------------------------------------------------------------*/
static int
transmit(unsigned short transmit_len)
{
uint8_t counter;
int ret = RADIO_TX_ERR;
rtimer_clock_t t0;
PRINTF("RF: Transmit\n");
if(!(rf_flags & RX_ACTIVE)) {
t0 = RTIMER_NOW();
on();
rf_flags |= WAS_OFF;
while(RTIMER_CLOCK_LT(RTIMER_NOW(), t0 + ONOFF_TIME));
}
if(channel_clear() == CC2538_RF_CCA_BUSY) {
RIMESTATS_ADD(contentiondrop);
return RADIO_TX_COLLISION;
}
/*
* prepare() double checked that TX_ACTIVE is low. If SFD is high we are
* receiving. Abort transmission and bail out with RADIO_TX_COLLISION
*/
if(REG(RFCORE_XREG_FSMSTAT1) & RFCORE_XREG_FSMSTAT1_SFD) {
RIMESTATS_ADD(contentiondrop);
return RADIO_TX_COLLISION;
}
/* Start the transmission */
ENERGEST_OFF(ENERGEST_TYPE_LISTEN);
ENERGEST_ON(ENERGEST_TYPE_TRANSMIT);
CC2538_RF_CSP_ISTXON();
counter = 0;
while(!((REG(RFCORE_XREG_FSMSTAT1) & RFCORE_XREG_FSMSTAT1_TX_ACTIVE))
&& (counter++ < 3)) {
clock_delay_usec(6);
}
if(!(REG(RFCORE_XREG_FSMSTAT1) & RFCORE_XREG_FSMSTAT1_TX_ACTIVE)) {
PRINTF("RF: TX never active.\n");
CC2538_RF_CSP_ISFLUSHTX();
ret = RADIO_TX_ERR;
} else {
/* Wait for the transmission to finish */
while(REG(RFCORE_XREG_FSMSTAT1) & RFCORE_XREG_FSMSTAT1_TX_ACTIVE);
ret = RADIO_TX_OK;
}
ENERGEST_OFF(ENERGEST_TYPE_TRANSMIT);
ENERGEST_ON(ENERGEST_TYPE_LISTEN);
if(rf_flags & WAS_OFF) {
rf_flags &= ~WAS_OFF;
off();
}
RIMESTATS_ADD(lltx);
return ret;
}
/*---------------------------------------------------------------------------*/
static int
send(const void *payload, unsigned short payload_len)
{
prepare(payload, payload_len);
return transmit(payload_len);
}
/*---------------------------------------------------------------------------*/
static int
read(void *buf, unsigned short bufsize)
{
uint8_t i;
uint8_t len;
uint8_t crc_corr;
int8_t rssi;
PRINTF("RF: Read\n");
if((REG(RFCORE_XREG_FSMSTAT1) & RFCORE_XREG_FSMSTAT1_FIFOP) == 0) {
return 0;
}
/* Check the length */
len = REG(RFCORE_SFR_RFDATA);
/* Check for validity */
if(len > CC2538_RF_MAX_PACKET_LEN) {
/* Oops, we must be out of sync. */
PRINTF("RF: bad sync\n");
RIMESTATS_ADD(badsynch);
CC2538_RF_CSP_ISFLUSHRX();
return 0;
}
if(len <= CC2538_RF_MIN_PACKET_LEN) {
PRINTF("RF: too short\n");
RIMESTATS_ADD(tooshort);
CC2538_RF_CSP_ISFLUSHRX();
return 0;
}
if(len - CHECKSUM_LEN > bufsize) {
PRINTF("RF: too long\n");
RIMESTATS_ADD(toolong);
CC2538_RF_CSP_ISFLUSHRX();
return 0;
}
/* If we reach here, chances are the FIFO is holding a valid frame */
PRINTF("RF: read (0x%02x bytes) = ", len);
len -= CHECKSUM_LEN;
/* Don't bother with uDMA for short frames (e.g. ACKs) */
if(CC2538_RF_CONF_RX_USE_DMA && len > UDMA_RX_SIZE_THRESHOLD) {
PRINTF("<uDMA payload>");
/* Set the transfer destination's end address */
udma_set_channel_dst(CC2538_RF_CONF_RX_DMA_CHAN,
(uint32_t)(buf) + len - 1);
/* Configure the control word */
udma_set_channel_control_word(CC2538_RF_CONF_RX_DMA_CHAN,
UDMA_RX_FLAGS | udma_xfer_size(len));
/* Enabled the RF RX uDMA channel */
udma_channel_enable(CC2538_RF_CONF_RX_DMA_CHAN);
/* Trigger the uDMA transfer */
udma_channel_sw_request(CC2538_RF_CONF_RX_DMA_CHAN);
/* Wait for the transfer to complete. */
while(udma_channel_get_mode(CC2538_RF_CONF_RX_DMA_CHAN));
} else {
for(i = 0; i < len; ++i) {
((unsigned char *)(buf))[i] = REG(RFCORE_SFR_RFDATA);
PRINTF("%02x", ((unsigned char *)(buf))[i]);
}
}
/* Read the RSSI and CRC/Corr bytes */
rssi = ((int8_t)REG(RFCORE_SFR_RFDATA)) - RSSI_OFFSET;
crc_corr = REG(RFCORE_SFR_RFDATA);
PRINTF("%02x%02x\n", (uint8_t)rssi, crc_corr);
/* MS bit CRC OK/Not OK, 7 LS Bits, Correlation value */
if(crc_corr & CRC_BIT_MASK) {
packetbuf_set_attr(PACKETBUF_ATTR_RSSI, rssi);
packetbuf_set_attr(PACKETBUF_ATTR_LINK_QUALITY, crc_corr & LQI_BIT_MASK);
RIMESTATS_ADD(llrx);
} else {
RIMESTATS_ADD(badcrc);
PRINTF("RF: Bad CRC\n");
CC2538_RF_CSP_ISFLUSHRX();
return 0;
}
#if CC2538_RF_CONF_SNIFFER
write_byte(magic[0]);
write_byte(magic[1]);
write_byte(magic[2]);
write_byte(magic[3]);
write_byte(len + 2);
for(i = 0; i < len; ++i) {
write_byte(((unsigned char *)(buf))[i]);
}
write_byte(rssi);
write_byte(crc_corr);
flush();
#endif
/* If FIFOP==1 and FIFO==0 then we had a FIFO overflow at some point. */
if(REG(RFCORE_XREG_FSMSTAT1) & RFCORE_XREG_FSMSTAT1_FIFOP) {
if(REG(RFCORE_XREG_FSMSTAT1) & RFCORE_XREG_FSMSTAT1_FIFO) {
process_poll(&cc2538_rf_process);
} else {
CC2538_RF_CSP_ISFLUSHRX();
}
}
return (len);
}
/*---------------------------------------------------------------------------*/
static int
receiving_packet(void)
{
PRINTF("RF: Receiving\n");
/*
* SFD high while transmitting and receiving.
* TX_ACTIVE high only when transmitting
*
* FSMSTAT1 & (TX_ACTIVE | SFD) == SFD <=> receiving
*/
return ((REG(RFCORE_XREG_FSMSTAT1)
& (RFCORE_XREG_FSMSTAT1_TX_ACTIVE | RFCORE_XREG_FSMSTAT1_SFD))
== RFCORE_XREG_FSMSTAT1_SFD);
}
/*---------------------------------------------------------------------------*/
static int
pending_packet(void)
{
PRINTF("RF: Pending\n");
return (REG(RFCORE_XREG_FSMSTAT1) & RFCORE_XREG_FSMSTAT1_FIFOP);
}
/*---------------------------------------------------------------------------*/
const struct radio_driver cc2538_rf_driver = {
init,
prepare,
transmit,
send,
read,
channel_clear,
receiving_packet,
pending_packet,
on,
off,
};
/*---------------------------------------------------------------------------*/
/**
* \brief Implementation of the cc2538 RF driver process
*
* This process is started by init(). It simply sits there waiting for
* an event. Upon frame reception, the RX ISR will poll this process.
* Subsequently, the contiki core will generate an event which will
* call this process so that the received frame can be picked up from
* the RF RX FIFO
*
*/
PROCESS_THREAD(cc2538_rf_process, ev, data)
{
int len;
PROCESS_BEGIN();
while(1) {
PROCESS_YIELD_UNTIL(ev == PROCESS_EVENT_POLL);
packetbuf_clear();
len = read(packetbuf_dataptr(), PACKETBUF_SIZE);
if(len > 0) {
packetbuf_set_datalen(len);
NETSTACK_RDC.input();
}
/* If we were polled due to an RF error, reset the transceiver */
if(rf_flags & RF_MUST_RESET) {
rf_flags = 0;
off();
init();
}
}
PROCESS_END();
}
/*---------------------------------------------------------------------------*/
/**
* \brief The cc2538 RF RX/TX ISR
*
* This is the interrupt service routine for all RF interrupts relating
* to RX and TX. Error conditions are handled by cc2538_rf_err_isr().
* Currently, we only acknowledge the FIFOP interrupt source.
*/
void
cc2538_rf_rx_tx_isr(void)
{
ENERGEST_ON(ENERGEST_TYPE_IRQ);
process_poll(&cc2538_rf_process);
/* We only acknowledge FIFOP so we can safely wipe out the entire SFR */
REG(RFCORE_SFR_RFIRQF0) = 0;
ENERGEST_OFF(ENERGEST_TYPE_IRQ);
}
/*---------------------------------------------------------------------------*/
/**
* \brief The cc2538 RF Error ISR
*
* This is the interrupt service routine for all RF errors. We
* acknowledge every error type and instead of trying to be smart and
* act differently depending on error condition, we simply reset the
* transceiver. RX FIFO overflow is an exception, we ignore this error
* since read() handles it anyway.
*
* However, we don't want to reset within this ISR. If the error occurs
* while we are reading a frame out of the FIFO, trashing the FIFO in
* the middle of read(), would result in further errors (RX underflows).
*
* Instead, we set a flag and poll the driver process. The process will
* reset the transceiver without any undesirable consequences.
*/
void
cc2538_rf_err_isr(void)
{
ENERGEST_ON(ENERGEST_TYPE_IRQ);
PRINTF("RF Error: 0x%08lx\n", REG(RFCORE_SFR_RFERRF));
/* If the error is not an RX FIFO overflow, set a flag */
if(REG(RFCORE_SFR_RFERRF) != RFCORE_SFR_RFERRF_RXOVERF) {
rf_flags |= RF_MUST_RESET;
}
REG(RFCORE_SFR_RFERRF) = 0;
process_poll(&cc2538_rf_process);
ENERGEST_OFF(ENERGEST_TYPE_IRQ);
}
/*---------------------------------------------------------------------------*/
/** @} */