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SAMA5: Fix issues with RX synch

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This commit is contained in:
Gregory Nutt 2013-11-12 14:56:00 -06:00
parent 43f7418d56
commit 5d2ff0d4dc
1 changed files with 51 additions and 16 deletions
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67
arch/arm/src/sama5/sam_ssc.c
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@ -117,8 +117,6 @@
# define SSC_HAVE_TX
#endif
#define SSC_DATNB (1) /* Data number per frame */
/* Check if we need the sample rate to set MCK/2 divider */
#undef SSC_HAVE_MCK2
@ -139,6 +137,29 @@
# define SSC_HAVE_MCK2 1
#endif
/* Waveform:
*
* |<---------------- PERIOD --------------->|
* ----+ +-----------------------------------+ +---
* | | | |
* +-----+ +----+
* |FSLEN|
* |<-STTDLY->|<--DATALEN-->|<--DATALEN-->| |
* |<-----DATALEN * DATNB----->|
*
* TK/RK is assumed to be a negative pulse
* DATALEN is configurable: CONFIG_SAMA5_SSC0_DATALEN
* FSLEN and STTDLY are fixed at two clocks
* DATNB is fixed a one work
*
* REVISIT: These will probably need to be configurable
*/
#define SSC_FSLEN (2) /* TF/RF plus width in clocks */
#define SSC_STTDLY (2) /* Delay to data start in clocks (same as FSLEN) */
#define SSC_DATNB (1) /* Number words per per frame */
#define SCC_PERIOD (SSC_FSLEN + CONFIG_SAMA5_SSC0_DATALEN * SSC_DATNB)
/* Clocking *****************************************************************/
/* Select MCU-specific settings
*
@ -1148,7 +1169,11 @@ static int ssc_rxdma_setup(struct sam_ssc_s *priv)
(uintptr_t)apb->samp + apb->nmaxbytes);
}
#if 1 /* REVISIT: Chained RX transfers */
while (0);
#else
while (!sq_empty(&priv->rx.pend));
#endif
/* Sample DMA registers */
@ -1549,7 +1574,11 @@ static int ssc_txdma_setup(struct sam_ssc_s *priv)
(uintptr_t)apb->samp + apb->nbytes);
}
#if 1 /* REVISIT: Chained TX transfers */
while (0);
#else
while (!sq_empty(&priv->tx.pend));
#endif
/* Sample DMA registers */
@ -2233,12 +2262,15 @@ static int ssc_rx_configure(struct sam_ssc_s *priv)
* SSC_RCMR_CKG_CONT No receive clock gating
* SSC_RCMR_START_EDGE Detection of any edge on RF signal
* SSC_RCMR_STOP Not selected
* SSC_RCMR_STTDLY(1) Receive start delay = 1
* SSC_RCMR_STTDLY(1) Receive start delay = 1 (same as FSLEN)
* SSC_RCMR_PERIOD(0) Receive period divider = 0
*
* REVISIT: This implementation assumes that on the transmitter
* can be the master (i.e, can generate the TK/RK clocking.
*/
regval |= (SSC_RCMR_CKI | SSC_RCMR_CKG_CONT | SSC_RCMR_START_EDGE |
SSC_RCMR_STTDLY(1) | SSC_RCMR_PERIOD(0));
SSC_RCMR_STTDLY(SSC_STTDLY - 1) | SSC_RCMR_PERIOD(0));
ssc_putreg(priv, SAM_SSC_RCMR_OFFSET, regval);
/* RFMR settings. Some of these settings will need to be configurable as well.
@ -2248,14 +2280,14 @@ static int ssc_rx_configure(struct sam_ssc_s *priv)
* SSC_RFMR_LOOP Determined by configuration
* SSC_RFMR_MSBF Most significant bit first
* SSC_RFMR_DATNB(n) Data number 'n' per frame (hard-coded)
* SSC_RFMR_FSLEN(0) Receive frame sync length = 0
* SSC_RFMR_FSLEN(1) Pulse length = FSLEN + (FSLEN_EXT * 16) + 1 = 2 clocks
* SSC_RFMR_FSOS_NONE RF pin is always in input
* SSC_RFMR_FSEDGE_POS Positive frame sync edge detection
* SSC_RFMR_FSLENEXT(0) FSLEN field extension = 0
*/
regval = (SSC_RFMR_DATLEN(CONFIG_SAMA5_SSC0_DATALEN - 1) | SSC_RFMR_MSBF |
SSC_RFMR_DATNB(SSC_DATNB - 1) | SSC_RFMR_FSLEN(0) |
SSC_RFMR_DATNB(SSC_DATNB - 1) | SSC_RFMR_FSLEN(SSC_FSLEN - 1) |
SSC_RFMR_FSOS_NONE | SSC_RFMR_FSLENEXT(0));
/* Loopback mode? */
@ -2337,7 +2369,7 @@ static int ssc_tx_configure(struct sam_ssc_s *priv)
*
* SSC_RCMR_CKI No transmitter clock inversion
* SSC_RCMR_CKG_CONT No transmit clock gating
* SSC_TCMR_STTDLY(1) Receive start delay = 1
* SSC_TCMR_STTDLY(1) Receive start delay = 2 clocks (same as FSLEN)
*
* If master (i.e., provides clocking):
* SSC_TCMR_START_CONT When data written to THR
@ -2346,16 +2378,21 @@ static int ssc_tx_configure(struct sam_ssc_s *priv)
* If slave (i.e., receives clocking):
* SSC_TCMR_START_EDGE Detection of any edge on TF signal
* SSC_TCMR_PERIOD(0) Receive period divider = 0
*
* The period signal is generated at clocks = 2 x (PERIOD+1), or
* PERIOD = (clocks / 2) - 1.
*/
if (priv->txclk == SSC_CLKSRC_MCKDIV)
{
regval |= (SSC_TCMR_CKG_CONT | SSC_TCMR_START_CONT | SSC_TCMR_STTDLY(1) |
SSC_TCMR_PERIOD(((CONFIG_SAMA5_SSC0_DATALEN * SSC_DATNB) / 2) - 1));
regval |= (SSC_TCMR_CKG_CONT | SSC_TCMR_START_CONT |
SSC_TCMR_STTDLY(SSC_STTDLY - 1) |
SSC_TCMR_PERIOD(SCC_PERIOD / 2 - 1));
}
else
{
regval |= (SSC_TCMR_CKG_CONT | SSC_TCMR_START_EDGE | SSC_TCMR_STTDLY(1) |
regval |= (SSC_TCMR_CKG_CONT | SSC_TCMR_START_EDGE |
SSC_TCMR_STTDLY(SSC_STTDLY - 1) |
SSC_TCMR_PERIOD(0));
}
@ -2369,14 +2406,13 @@ static int ssc_tx_configure(struct sam_ssc_s *priv)
* SSC_TFMR_MSBF Most significant bit first
* SSC_TFMR_DATNB(n) Data number 'n' per frame (hard-coded)
* SSC_TFMR_FSDEN Frame sync data is enabled
* SSC_TFMR_FSLEN(1) Pulse length = + (FSLEN_EXT * 16) + 1 = 2 TX clocks
* SSC_TFMR_FSLENEXT(0) FSLEN field extension = 0
*
* If master (i.e., provides clocking):
* SSC_TFMR_FSLEN(n) Receive frame sync length depends on data width
* SSC_TFMR_FSOS_NEGATIVE Negative pulse TF output
*
* If slave (i.e, receives clocking):
* SSC_TFMR_FSLEN(0) Receive frame sync length = 0
* SSC_TFMR_FSOS_NONE TF is an output
*/
@ -2384,15 +2420,14 @@ static int ssc_tx_configure(struct sam_ssc_s *priv)
{
regval = (SSC_TFMR_DATLEN(CONFIG_SAMA5_SSC0_DATALEN - 1) |
SSC_TFMR_MSBF | SSC_TFMR_DATNB(SSC_DATNB - 1) |
SSC_TFMR_FSLEN(CONFIG_SAMA5_SSC0_DATALEN - 1) |
SSC_TFMR_FSOS_NEGATIVE | SSC_TFMR_FSDEN |
SSC_TFMR_FSLENEXT(0));
SSC_TFMR_FSLEN(SSC_FSLEN - 1) | SSC_TFMR_FSOS_NEGATIVE |
SSC_TFMR_FSDEN | SSC_TFMR_FSLENEXT(0));
}
else
{
regval = (SSC_TFMR_DATLEN(CONFIG_SAMA5_SSC0_DATALEN - 1) |
SSC_TFMR_MSBF | SSC_TFMR_DATNB(SSC_DATNB - 1) |
SSC_TFMR_FSLEN(0) | SSC_TFMR_FSOS_NONE |
SSC_TFMR_FSLEN(SSC_FSLEN - 1) | SSC_TFMR_FSOS_NONE |
SSC_TFMR_FSDEN | SSC_TFMR_FSLENEXT(0));
}