* \author Daniele Basile <asterix@develer.com>
*/
+#include "dac_sam3.h"
#include "cfg/cfg_dac.h"
#include <cfg/log.h>
#include <drv/dac.h>
-
+#include <cpu/irq.h>
#include <drv/irq_cm3.h>
+#include <cpu/types.h>
+
+#include <mware/event.h>
+
#include <io/cm3.h>
#include <string.h>
+struct DacHardware
+{
+ uint16_t channels;
+ uint32_t rate;
+ bool end;
+};
+
+struct DacHardware dac_hw;
+
+
+/* We use event to signal the end of conversion */
+static Event buff_emtpy;
+#if CONFIG_DAC_TIMER == DACC_TRGSEL_TIO_CH0 /* Select Timer counter TIO Channel 0 */
+ #define DAC_TC_ID TC0_ID
+ #define DAC_TC_CCR TC0_CCR0
+ #define DAC_TC_IDR TC0_IDR0
+ #define DAC_TC_CMR TC0_CMR0
+ #define DAC_TC_SR TC0_SR0
+ #define DAC_TC_RA TC0_RA0
+ #define DAC_TC_RC TC0_RC0
+#elif CONFIG_DAC_TIMER == DACC_TRGSEL_TIO_CH1 /* Select Timer counter TIO Channel 1 */
+ #define DAC_TC_ID TC1_ID
+ #define DAC_TC_CCR TC0_CCR1
+ #define DAC_TC_IDR TC0_IDR1
+ #define DAC_TC_CMR TC0_CMR1
+ #define DAC_TC_SR TC0_SR1
+ #define DAC_TC_RA TC0_RA1
+ #define DAC_TC_RC TC0_RC1
+#elif CONFIG_DAC_TIMER == DACC_TRGSEL_TIO_CH2 /* Select Timer counter TIO Channel 2 */
+ #define DAC_TC_ID TC2_ID
+ #define DAC_TC_CCR TC0_CCR2
+ #define DAC_TC_IDR TC0_IDR2
+ #define DAC_TC_CMR TC0_CMR2
+ #define DAC_TC_SR TC0_SR2
+ #define DAC_TC_RA TC0_RA2
+ #define DAC_TC_RC TC0_RC2
+#elif CONFIG_DAC_TIMER == DACC_TRGSEL_PWM0 || CONFIG_DAC_TIMER == DACC_TRGSEL_PWM1
+ #error unimplemented pwm triger select.
+#endif
-static int sam3x_dac_write(DacContext *ctx, unsigned channel, uint16_t sample)
+
+INLINE void tc_init(void)
{
- ASSERT(channel <= 1);
+ pmc_periphEnable(DAC_TC_ID);
+
+ /* Disable TC clock */
+ DAC_TC_CCR = BV(TC_CCR_CLKDIS);
+ /* Disable interrupts */
+ DAC_TC_IDR = 0xFFFFFFFF;
+ /* Clear status register */
+ volatile uint32_t dummy = DAC_TC_SR;
+ (void)dummy;
+
+ /*
+ * Setup the timer counter:
+ * - select clock TCLK1 (MCK/2)
+ * - enable wave form mode
+ * - RA compare effect SET
+ * - RC compare effect CLEAR
+ * - UP mode with automatic trigger on RC Compare
+ */
+ DAC_TC_CMR = TC_TIMER_CLOCK1 | BV(TC_CMR_WAVE) | TC_CMR_ACPA_SET | TC_CMR_ACPC_CLEAR | BV(TC_CMR_CPCTRG);
+
+
+ /* Setup the pio: TODO: fix for more generic */
+ PIOB_PDR = BV(25);
+ PIO_PERIPH_SEL(PIOB_BASE, BV(25), PIO_PERIPH_B);
+}
+
+INLINE void tc_setup(uint32_t freq, size_t n_sample)
+{
+ /*
+ * Compute the sample frequency
+ * the RC counter will update every MCK/2 (see above)
+ * so to convert one sample at the user freq we generate
+ * the trigger every TC_CLK / (numer_of_sample * user_freq)
+ * where TC_CLK = MCK / 2.
+ */
+ uint32_t rc = DIV_ROUND((CPU_FREQ / 2), n_sample * freq);
+ DAC_TC_RC = rc;
+ /* generate the square wave with duty = 50% */
+ DAC_TC_RA = DIV_ROUND(50 * rc, 100);
+}
+
+INLINE void tc_start(void)
+{
+ DAC_TC_CCR = BV(TC_CCR_CLKEN)| BV(TC_CCR_SWTRG);
+}
+
+INLINE void tc_stop(void)
+{
+ DAC_TC_CCR = BV(TC_CCR_CLKDIS);
+}
+
+static int sam3x_dac_write(struct Dac *dac, unsigned channel, uint16_t sample)
+{
+ (void)dac;
+
+ ASSERT(channel <= DAC_MAXCH);
DACC_MR |= (channel << DACC_USER_SEL_SHIFT) & DACC_USER_SEL_MASK;
DACC_CHER |= BV(channel);
return 0;
}
-static void sam3x_dac_setCh(struct DacContext *ctx, uint32_t mask)
+static void sam3x_dac_setCh(struct Dac *dac, uint32_t mask)
{
+ /* we have only the ch0 and ch1 */
+ ASSERT(mask < BV(3));
+ dac->hw->channels = mask;
+
+ if (mask & BV(DACC_CH0))
+ DACC_MR |= (DACC_CH0 << DACC_USER_SEL_SHIFT) & DACC_USER_SEL_MASK;
+
+ if (mask & BV(DACC_CH1))
+ DACC_MR |= (DACC_CH1 << DACC_USER_SEL_SHIFT) & DACC_USER_SEL_MASK;
+
+ DACC_CHER |= mask;
+
}
-static void sam3x_dac_setSampleRate(struct DacContext *ctx, uint32_t rate)
+static void sam3x_dac_setSampleRate(struct Dac *dac, uint32_t rate)
{
+ /* Eneble hw trigger */
+ DACC_MR |= BV(DACC_TRGEN) | (CONFIG_DAC_TIMER << DACC_TRGSEL_SHIFT);
+ dac->hw->rate = rate;
}
-static void sam3x_dac_conversion(struct DacContext *ctx, void *buf, size_t len)
+static void sam3x_dac_conversion(struct Dac *dac, void *buf, size_t len)
{
- DACC_TPR = (uint32_t)buf ;
+ /* setup timer and start it */
+ tc_setup(dac->hw->rate, len);
+ tc_start();
+
+ /* Setup dma and start it */
+ DACC_TPR = (uint32_t)buf;
DACC_TCR = len;
DACC_PTCR |= BV(DACC_PTCR_TXTEN);
}
-static bool sam3x_dac_isFinished(struct DacContext *ctx)
+static uint16_t *sample_buff;
+static size_t next_idx = 0;
+static size_t chunk_size = 0;
+static size_t remaing_size = 0;
+
+static DECLARE_ISR(irq_dac)
{
+ if (DACC_ISR & BV(DACC_ENDTX))
+ {
+ if (remaing_size > 0)
+ {
+ DACC_TNPR = (uint32_t)&sample_buff[next_idx];
+ DACC_TNCR = chunk_size;
+
+ remaing_size -= chunk_size;
+ next_idx += chunk_size;
+ }
+ else
+ /* Clear the pending irq when the dma ends the conversion */
+ DACC_TCR = 1;
+ }
+ event_do(&buff_emtpy);
}
-static void sam3x_dac_start(struct DacContext *ctx, void *buf, size_t len, size_t slicelen)
+
+static bool sam3x_dac_isFinished(struct Dac *dac)
{
+ return dac->hw->end;
}
-static void sam3x_dac_stop(struct DacContext *ctx)
+static void sam3x_dac_start(struct Dac *dac, void *_buf, size_t len, size_t slice_len)
{
+ ASSERT(dac);
+ ASSERT(len >= slice_len);
+
+ /* Reset the previous status. */
+ dac->hw->end = false;
+
+ sample_buff = (uint16_t *)_buf;
+ next_idx = 0;
+ chunk_size = slice_len;
+ remaing_size = len;
+
+
+ /* Program the dma with the first and second chunk of samples and update counter */
+ dac->ctx.callback(dac, &sample_buff[0], chunk_size);
+ DACC_TPR = (uint32_t)&sample_buff[0];
+ DACC_TCR = chunk_size;
+ remaing_size -= chunk_size;
+ next_idx += chunk_size;
+
+ if (chunk_size <= remaing_size)
+ {
+ dac->ctx.callback(dac, &sample_buff[next_idx], chunk_size);
+
+ DACC_TNPR = (uint32_t)&sample_buff[next_idx];
+ DACC_TNCR = chunk_size;
+
+ remaing_size -= chunk_size;
+ next_idx += chunk_size;
+
+ }
+
+ DACC_PTCR |= BV(DACC_PTCR_TXTEN);
+ DACC_IER = BV(DACC_ENDTX);
+
+ /* Set up timer and trig the conversions */
+ tc_setup(dac->hw->rate, len);
+ tc_start();
+
+ while (1)
+ {
+ event_wait(&buff_emtpy);
+ if (remaing_size <= 0)
+ {
+ DAC_TC_CCR = BV(TC_CCR_CLKDIS);
+ dac->hw->end = true;
+ next_idx = 0;
+ chunk_size = 0;
+ remaing_size = 0;
+ break;
+ }
+
+ dac->ctx.callback(dac, &sample_buff[next_idx], chunk_size);
+ }
+}
+
+static void sam3x_dac_stop(struct Dac *dac)
+{
+ dac->hw->end = false;
+ /* Disable the irq, timer and channel */
+ DACC_IDR = BV(DACC_ENDTX);
+ DACC_PTCR |= BV(DACC_PTCR_TXTDIS);
+ DAC_TC_CCR = BV(TC_CCR_CLKDIS);
}
-void dac_init(struct DacContext *ctx)
+void dac_init(struct Dac *dac)
{
- ctx->write = sam3x_dac_write;
- ctx->setCh = sam3x_dac_setCh;
- ctx->setSampleRate = sam3x_dac_setSampleRate;
- ctx->conversion = sam3x_dac_conversion;
- ctx->isFinished = sam3x_dac_isFinished;
- ctx->start = sam3x_dac_start;
- ctx->stop = sam3x_dac_stop;
+ /* Initialize the dataready event */
+ event_initGeneric(&buff_emtpy);
+ /* Fill the virtual table */
+ dac->ctx.write = sam3x_dac_write;
+ dac->ctx.setCh = sam3x_dac_setCh;
+ dac->ctx.setSampleRate = sam3x_dac_setSampleRate;
+ dac->ctx.conversion = sam3x_dac_conversion;
+ dac->ctx.isFinished = sam3x_dac_isFinished;
+ dac->ctx.start = sam3x_dac_start;
+ dac->ctx.stop = sam3x_dac_stop;
+ DB(dac->ctx._type = DAC_SAM3X;)
+ dac->hw = &dac_hw;
- /* Clock ADC peripheral */
+ /* Clock DAC peripheral */
pmc_periphEnable(DACC_ID);
+ /* Reset hw */
DACC_CR |= BV(DACC_SWRST);
DACC_MR = 0;
- /* Refresh period */
- DACC_MR |= (16 << DACC_REFRESH_SHIFT) & DACC_REFRESH_MASK;
- /* Start up */
- DACC_MR |= (DACC_MR_STARTUP_0 << DACC_STARTUP_SHIFT) & DACC_STARTUP_MASK;
+ /* Configure the dac */
+ DACC_MR |= (CONFIG_DAC_REFRESH << DACC_REFRESH_SHIFT) & DACC_REFRESH_MASK;
+ DACC_MR |= (CONFIG_DAC_STARTUP << DACC_STARTUP_SHIFT) & DACC_STARTUP_MASK;
+
+ DACC_IDR = 0xFFFFFFFF;
+ sysirq_setHandler(INT_DACC, irq_dac);
+ tc_init();
}