osd-contiki/platform/msb430/dev/dma.c
2007-09-21 13:51:09 +00:00

129 lines
3.6 KiB
C

/*
* Copyright (c) 2007, Swedish Institute of Computer Science
* 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 Institute 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 INSTITUTE 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 INSTITUTE 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.
*
* This file is part of the Contiki operating system.
*
*/
/**
* \file
* DMA interrupt handling.
* \author
* Nicolas Tsiftes <nvt@sics.se>
*/
#include <io.h>
#include <signal.h>
#include "contiki-msb430.h"
#include "dev/cc1020.h"
#include "dev/dma.h"
static struct process *subscribers[DMA_LINES];
process_event_t dma_event;
interrupt(DACDMA_VECTOR) irq_dacdma(void)
{
if (DMA0CTL & DMAIFG) {
DMA0CTL &= ~(DMAIFG | DMAIE);
if (subscribers[0] != NULL) {
process_post(subscribers[0], dma_event, NULL);
}
LPM_AWAKE();
}
if (DMA1CTL & DMAIFG) {
DMA1CTL &= ~(DMAIFG | DMAIE);
if (subscribers[1] != NULL) {
process_post(subscribers[1], dma_event, NULL);
}
LPM_AWAKE();
}
if (DMA2CTL & DMAIFG) {
DMA2CTL &= ~(DMAIFG | DMAIE);
if (subscribers[2] != NULL) {
process_post(subscribers[2], dma_event, NULL);
}
LPM_AWAKE();
}
if (DAC12_0CTL & DAC12IFG) {
DAC12_0CTL &= ~(DAC12IFG | DAC12IE);
}
if (DAC12_1CTL & DAC12IFG) {
DAC12_1CTL &= ~(DAC12IFG | DAC12IE);
}
}
void
dma_init(void)
{
dma_event = process_alloc_event();
}
int
dma_subscribe(int line, struct process *p)
{
if (line >= DMA_LINES)
return -1;
subscribers[line] = p;
return 0;
}
void
dma_transfer(unsigned char *buf, unsigned len)
{
// Configure DMA Channel 0 for UART0 TXIFG.
DMACTL0 = DMA0TSEL_4;
// No DMAONFETCH, ROUNDROBIN, ENNMI.
DMACTL1 = 0x0000;
/*
* Set single transfer mode with byte-per-byte transfers.
*
* The source address is incremented for each byte, while the
* destination address remains constant.
*
* In order to avoid missing the first rising edge of the trigger
* signal, it is important to use the level-sensitive trigger when
* using USART transfer interrupts.
*/
DMA0CTL = DMADT_0 | DMADSTINCR_0 | DMASRCINCR_3 | DMASBDB | DMALEVEL;
DMA0SA = (unsigned) buf;
DMA0DA = (unsigned) &TXBUF0;
DMA0SZ = len;
DMA0CTL |= DMAEN | DMAIE; // enable DMA and interrupts
U0CTL &= ~SWRST; // enable UART state machine, starts transfer
}