more DMA cleanup

This commit is contained in:
Jorj Bauer 2022-01-22 19:55:12 -05:00
parent 4f266a7f4f
commit 7d4505c83f
2 changed files with 19 additions and 55 deletions

View File

@ -96,7 +96,7 @@
// 3 of these, one for each of the 3 busses, so that 3 separate
// displays could be driven. FIXME: I don't really need all 3 in this
// application, so this can be pared down.
static RA8875_t4 *_dmaActiveDisplay[3];
static RA8875_t4 *_dmaActiveDisplay = NULL;
RA8875_t4::RA8875_t4(const uint8_t cs_pin, const uint8_t rst_pin, const uint8_t mosi_pin, const uint8_t sck_pin, const uint8_t miso_pin)
{
@ -109,9 +109,8 @@ RA8875_t4::RA8875_t4(const uint8_t cs_pin, const uint8_t rst_pin, const uint8_t
_pspi = NULL;
_pfbtft = NULL;
_dma_state = 0;
_frame_complete_callback = NULL;
_dma_frame_count = 0;
_dmaActiveDisplay[0] = _dmaActiveDisplay[1] = _dmaActiveDisplay[2] = NULL;
_dmaActiveDisplay = NULL;
}
RA8875_t4::~RA8875_t4()
@ -127,15 +126,12 @@ void RA8875_t4::begin(uint32_t spi_clock, uint32_t spi_clock_read)
// figure out which SPI bus we're using
if (SPI.pinIsMOSI(_mosi) && ((_miso == 0xff) || SPI.pinIsMISO(_miso)) && SPI.pinIsSCK(_sck)) {
_pspi = &SPI;
_spi_num = 0;
_pimxrt_spi = &IMXRT_LPSPI4_S;
} else if (SPI1.pinIsMOSI(_mosi) && ((_miso == 0xff) || SPI1.pinIsMISO(_miso)) && SPI1.pinIsSCK(_sck)) {
_pspi = &SPI1;
_spi_num = 1;
_pimxrt_spi = &IMXRT_LPSPI3_S;
} else if (SPI2.pinIsMOSI(_mosi) && ((_miso == 0xff) || SPI2.pinIsMISO(_miso)) && SPI2.pinIsSCK(_sck)) {
_pspi = &SPI2;
_spi_num = 2;
_pimxrt_spi = &IMXRT_LPSPI1_S;
} else {
Serial.println("Pins given are not valid SPI bus pins");
@ -300,29 +296,23 @@ void RA8875_t4::initDMASettings()
// Each DMA structure can only track 32767 words written (where a
// word here is 8 bits). So we need 12 of these to cover the whole
// set of 800*480 display data.
// set of 800*480 display data. And we're assuming that they are
// evenly divisible, and that the DMA engine won't care if the
// data isn't all aligned to 2^15 boundaries.
uint16_t pixelsWrittenPerDMAreq = COUNT_PIXELS_WRITE / 12;
if (_dma_state & RA8875_DMA_EVER_INIT) {
// Just quickly reset the pointers and sizes
for (int i=0; i<11; i++) {
for (int i=0; i<12; i++) {
_dmasettings[i].sourceBuffer(&_pfbtft[pixelsWrittenPerDMAreq*i], pixelsWrittenPerDMAreq);
}
uint32_t leftoverPixelsToWrite = COUNT_PIXELS_WRITE - (pixelsWrittenPerDMAreq * 11);
_dmasettings[11].sourceBuffer(&_pfbtft[pixelsWrittenPerDMAreq*11], leftoverPixelsToWrite);
} else {
for (int i=0; i<11; i++) {
for (int i=0; i<12; i++) {
_dmasettings[i].sourceBuffer(&_pfbtft[pixelsWrittenPerDMAreq*i], pixelsWrittenPerDMAreq);
_dmasettings[i].destination(_pimxrt_spi->TDR); // DMA sends data to LPSPI's transmit data register
_dmasettings[i].TCD->ATTR_DST = 0; // 8-bit destination size (%000)
_dmasettings[i].replaceSettingsOnCompletion(_dmasettings[(i+1)%12]);
}
// The last one has a short write to perform...
uint32_t leftoverPixelsToWrite = COUNT_PIXELS_WRITE - (pixelsWrittenPerDMAreq * 11);
_dmasettings[11].sourceBuffer(&_pfbtft[pixelsWrittenPerDMAreq*11], leftoverPixelsToWrite);
_dmasettings[11].destination(_pimxrt_spi->TDR); // DMA sends data to LPSPI's transmit data register
_dmasettings[11].TCD->ATTR_DST = 0; // 8-bit destination size (%000)
_dmasettings[11].replaceSettingsOnCompletion(_dmasettings[0]);
// "half done" for 12 is at the end of index 5, so we don't have to set up interruptAtHalf()
// but we do have to change the way we deal with sub-frame counting. If we need it. I don't
// think we do, so I'm leaving this here as a comment for now...
@ -344,14 +334,14 @@ bool RA8875_t4::updateScreenAsync(bool update_cont)
{
if (!_pfbtft) return false;
// Half of main ram has a 32k cache. This tells it to flush the cache if necessary.
if ((uint32_t)_pfbtft >= 0x20200000u) arm_dcache_flush(_pfbtft, RA8875_WIDTH*RA8875_HEIGHT);
if (_dma_state & RA8875_DMA_ACTIVE) {
return false;
}
initDMASettings();
// Half of main ram has a 32k cache. This tells it to flush the cache if necessary.
if ((uint32_t)_pfbtft >= 0x20200000u) arm_dcache_flush(_pfbtft, RA8875_WIDTH*RA8875_HEIGHT);
// Don't need to reset the window b/c we never change it; but set the X/Y cursor back to the origin
_writeRegister(RA8875_CURV0, 0);
_writeRegister(RA8875_CURV0+1, 0);
@ -372,17 +362,12 @@ bool RA8875_t4::updateScreenAsync(bool update_cont)
maybeUpdateTCR(LPSPI_TCR_FRAMESZ(7) | LPSPI_TCR_RXMSK /*| LPSPI_TCR_CONT*/);
// Set up the DMA Enable Register to enable transmit DMA (and not receive DMA)
_pimxrt_spi->DER = LPSPI_DER_TDDE;
// Clear the status register %0011 1111 0000 0000 == set DMF, REF,
// TEF, TCF, FCF, WCF; clear MBF, RDF, TDF. MBF: busy flag; DMF:
// data match; REF: rec error flag; TEF: xmit error flag; TCF:
// xmit complete flag; FCF: frame complete flag; WCF: word
// complete flag; RDF: rec data flag; TDF: xmit data flag
_pimxrt_spi->SR &= 0x3f00; // clear status flags, but leave error flags
_pimxrt_spi->SR &= 0x3f00; // clear status flags RDF and TDF (rx and tx data flags), but leave error flags
_dmatx.triggerAtHardwareEvent( _spi_hardware->tx_dma_channel );
_dmatx = _dmasettings[0];
_dma_frame_count = 0;
_dmaActiveDisplay[_spi_num] = this;
_dmaActiveDisplay = this;
_dmatx.begin(false);
_dmatx.enable();
@ -506,15 +491,8 @@ void RA8875_t4::maybeUpdateTCR(uint32_t requested_tcr_state)
}
void RA8875_t4::dmaInterrupt(void) {
if (_dmaActiveDisplay[0]) {
_dmaActiveDisplay[0]->process_dma_interrupt();
}
if (_dmaActiveDisplay[1]) {
_dmaActiveDisplay[1]->process_dma_interrupt();
}
if (_dmaActiveDisplay[2]) {
_dmaActiveDisplay[2]->process_dma_interrupt();
}
if (_dmaActiveDisplay)
_dmaActiveDisplay->process_dma_interrupt();
}
void RA8875_t4::process_dma_interrupt(void) {
@ -529,26 +507,15 @@ void RA8875_t4::process_dma_interrupt(void) {
_pimxrt_spi->FCR = _spi_fcr_save;
_pimxrt_spi->DER = 0; // turn off tx and rx DMA
_pimxrt_spi->CR = LPSPI_CR_MEN | LPSPI_CR_RRF | LPSPI_CR_RTF; //RRF: reset receive FIFO; RTF: reset transmit FIFO; MEN: enable module
_pimxrt_spi->SR &= 0x3f00; // clear status flags, but leave error flags
// DMF: data match flag set
// REF: receive error flag set
// TEF: transmit error flag set
// TCF: transfer complete flag set
// FCF: frame complete flag set
// WCF: word complete flag set
_pimxrt_spi->SR &= 0x3f00; // clear status flags RDF and TDF (rx and tx data flags), but leave error flags
maybeUpdateTCR(LPSPI_TCR_FRAMESZ(7));
// *** the other modules send a NOP here, don't know why
_endSend();
_dma_state &= ~RA8875_DMA_ACTIVE;
_dmaActiveDisplay[_spi_num] = 0;
_dmaActiveDisplay = 0;
} else {
if (_frame_complete_callback)
(*_frame_complete_callback)();
else {
// Try to flush memory
if ((uint32_t)_pfbtft >= 0x20200000u)
arm_dcache_flush(_pfbtft, RA8875_WIDTH*RA8875_HEIGHT);
}
// Try to flush memory
if ((uint32_t)_pfbtft >= 0x20200000u)
arm_dcache_flush(_pfbtft, RA8875_WIDTH*RA8875_HEIGHT);
}
// make sure the code is synchronized - memory access must be
// complete before we continue

View File

@ -69,7 +69,6 @@ private:
SPIClass *_pspi;
IMXRT_LPSPI_t *_pimxrt_spi;
SPIClass::SPI_Hardware_t *_spi_hardware;
uint8_t _spi_num;
uint32_t _spi_clock; // desired clock
uint32_t _spi_clock_read;
uint32_t _clock; // current clock, used in starting transactions (b/c we have to slow down sometimes)
@ -83,8 +82,6 @@ private:
uint32_t _spi_tcr_current;
volatile uint32_t _dma_frame_count;
void (*_frame_complete_callback)();
protected:
void DIRECT_WRITE_LOW(volatile uint32_t * base, uint32_t mask) __attribute__((always_inline)) {
*(base+34) = mask;