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circuitpython/ports/atmel-samd/shared_dma.c

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/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2017 Scott Shawcroft for Adafruit Industries
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "shared_dma.h"
#include <string.h>
#include "py/gc.h"
#include "py/mpstate.h"
#include "hal/utils/include/utils.h"
#include "shared-bindings/microcontroller/__init__.h"
COMPILER_ALIGNED(16) static DmacDescriptor dma_descriptors[DMA_CHANNEL_COUNT];
// Don't use these directly. They are used by the DMA engine itself.
COMPILER_ALIGNED(16) static DmacDescriptor write_back_descriptors[DMA_CHANNEL_COUNT];
#ifdef SAMD21
#define FIRST_SERCOM_RX_TRIGSRC 0x01
#define FIRST_SERCOM_TX_TRIGSRC 0x02
#endif
#ifdef SAMD51
#define FIRST_SERCOM_RX_TRIGSRC 0x04
#define FIRST_SERCOM_TX_TRIGSRC 0x05
#endif
static uint8_t sercom_index(Sercom* sercom) {
#ifdef SAMD21
return ((uint32_t) sercom - (uint32_t) SERCOM0) / 0x400;
#else
const Sercom* sercoms[SERCOM_INST_NUM] = SERCOM_INSTS;
for (uint8_t i = 0; i < SERCOM_INST_NUM; i++) {
if (sercoms[i] == sercom) {
return i;
}
}
return 0;
#endif
}
void dma_configure(uint8_t channel_number, uint8_t trigsrc, bool output_event) {
#ifdef SAMD21
common_hal_mcu_disable_interrupts();
/** Select the DMA channel and clear software trigger */
DMAC->CHID.reg = DMAC_CHID_ID(channel_number);
DMAC->CHCTRLA.reg &= ~DMAC_CHCTRLA_ENABLE;
DMAC->CHCTRLA.reg = DMAC_CHCTRLA_SWRST;
DMAC->SWTRIGCTRL.reg &= (uint32_t)(~(1 << channel_number));
uint32_t event_output_enable = 0;
if (output_event) {
event_output_enable = DMAC_CHCTRLB_EVOE;
}
DMAC->CHCTRLB.reg = DMAC_CHCTRLB_LVL_LVL0 |
DMAC_CHCTRLB_TRIGSRC(trigsrc) |
DMAC_CHCTRLB_TRIGACT_BEAT |
event_output_enable;
common_hal_mcu_enable_interrupts();
#endif
#ifdef SAMD51
DmacChannel* channel = &DMAC->Channel[channel_number];
channel->CHCTRLA.reg &= ~DMAC_CHCTRLA_ENABLE;
channel->CHCTRLA.reg = DMAC_CHCTRLA_SWRST;
if (output_event) {
channel->CHEVCTRL.reg = DMAC_CHEVCTRL_EVOE;
}
channel->CHCTRLA.reg = DMAC_CHCTRLA_TRIGSRC(trigsrc) |
DMAC_CHCTRLA_TRIGACT_BURST |
DMAC_CHCTRLA_BURSTLEN_SINGLE;
#endif
}
void dma_enable_channel(uint8_t channel_number) {
#ifdef SAMD21
common_hal_mcu_disable_interrupts();
/** Select the DMA channel and clear software trigger */
DMAC->CHID.reg = DMAC_CHID_ID(channel_number);
DMAC->CHCTRLA.bit.ENABLE = true;
common_hal_mcu_enable_interrupts();
#endif
#ifdef SAMD51
DmacChannel* channel = &DMAC->Channel[channel_number];
channel->CHCTRLA.bit.ENABLE = true;
#endif
}
void dma_disable_channel(uint8_t channel_number) {
#ifdef SAMD21
common_hal_mcu_disable_interrupts();
/** Select the DMA channel and clear software trigger */
DMAC->CHID.reg = DMAC_CHID_ID(channel_number);
DMAC->CHCTRLA.bit.ENABLE = false;
common_hal_mcu_enable_interrupts();
#endif
#ifdef SAMD51
DmacChannel* channel = &DMAC->Channel[channel_number];
channel->CHCTRLA.bit.ENABLE = false;
#endif
}
bool dma_channel_enabled(uint8_t channel_number) {
#ifdef SAMD21
common_hal_mcu_disable_interrupts();
/** Select the DMA channel and clear software trigger */
DMAC->CHID.reg = DMAC_CHID_ID(channel_number);
bool enabled = DMAC->CHCTRLA.bit.ENABLE;
common_hal_mcu_enable_interrupts();
return enabled;
#endif
#ifdef SAMD51
DmacChannel* channel = &DMAC->Channel[channel_number];
return channel->CHCTRLA.bit.ENABLE;
#endif
}
uint8_t dma_transfer_status(uint8_t channel_number) {
#ifdef SAMD21
common_hal_mcu_disable_interrupts();
/** Select the DMA channel and clear software trigger */
DMAC->CHID.reg = DMAC_CHID_ID(channel_number);
uint8_t status = DMAC->CHINTFLAG.reg;
common_hal_mcu_enable_interrupts();
return status;
#endif
#ifdef SAMD51
DmacChannel* channel = &DMAC->Channel[channel_number];
return channel->CHINTFLAG.reg;
#endif
}
static bool channel_free(uint8_t channel_number) {
#ifdef SAMD21
common_hal_mcu_disable_interrupts();
DMAC->CHID.reg = DMAC_CHID_ID(channel_number);
bool channel_free = DMAC->CHSTATUS.reg == 0;
common_hal_mcu_enable_interrupts();
return channel_free;
#endif
#ifdef SAMD51
DmacChannel* channel = &DMAC->Channel[channel_number];
return channel->CHSTATUS.reg == 0;
#endif
}
void init_shared_dma(void) {
// Turn on the clocks
#ifdef SAMD51
MCLK->AHBMASK.reg |= MCLK_AHBMASK_DMAC;
#endif
#ifdef SAMD21
PM->AHBMASK.reg |= PM_AHBMASK_DMAC;
PM->APBBMASK.reg |= PM_APBBMASK_DMAC;
#endif
DMAC->CTRL.reg = DMAC_CTRL_SWRST;
DMAC->BASEADDR.reg = (uint32_t) dma_descriptors;
DMAC->WRBADDR.reg = (uint32_t) write_back_descriptors;
DMAC->CTRL.reg = DMAC_CTRL_DMAENABLE | DMAC_CTRL_LVLEN0;
for (uint8_t i = 0; i < AUDIO_DMA_CHANNEL_COUNT; i++) {
dma_configure(i, 0, true);
}
}
// Do write and read simultaneously. If buffer_out is NULL, write the tx byte over and over.
// If buffer_out is a real buffer, ignore tx.
// DMAs buffer_out -> dest
// DMAs src -> buffer_in
static int32_t shared_dma_transfer(void* peripheral,
const uint8_t* buffer_out, volatile uint32_t* dest,
volatile uint32_t* src, uint8_t* buffer_in,
uint32_t length, uint8_t tx) {
if (!channel_free(SHARED_TX_CHANNEL) ||
(buffer_in != NULL && !channel_free(SHARED_RX_CHANNEL))) {
return -1;
}
uint32_t beat_size = DMAC_BTCTRL_BEATSIZE_BYTE;
bool sercom = true;
bool tx_active = false;
bool rx_active = false;
uint16_t beat_length = length;
#ifdef SAMD51
if (peripheral == QSPI) {
// Check input alignment on word boundaries.
if ((((uint32_t) buffer_in) & 0x3) != 0 ||
(((uint32_t) buffer_out) & 0x3) != 0) {
return -3;
}
beat_size = DMAC_BTCTRL_BEATSIZE_WORD | DMAC_BTCTRL_SRCINC | DMAC_BTCTRL_DSTINC;
beat_length /= 4;
sercom = false;
if (buffer_out != NULL) {
dma_configure(SHARED_TX_CHANNEL, QSPI_DMAC_ID_TX, false);
tx_active = true;
} else {
dma_configure(SHARED_RX_CHANNEL, QSPI_DMAC_ID_RX, false);
rx_active = true;
}
} else {
#endif
// sercom index is incorrect for SAMD51
dma_configure(SHARED_TX_CHANNEL, sercom_index(peripheral) * 2 + FIRST_SERCOM_TX_TRIGSRC, false);
tx_active = true;
if (buffer_in != NULL) {
dma_configure(SHARED_RX_CHANNEL, sercom_index(peripheral) * 2 + FIRST_SERCOM_RX_TRIGSRC, false);
rx_active = true;
}
#ifdef SAMD51
}
#endif
// Set up RX first.
if (rx_active) {
DmacDescriptor* rx_descriptor = &dma_descriptors[SHARED_RX_CHANNEL];
rx_descriptor->BTCTRL.reg = beat_size | DMAC_BTCTRL_DSTINC;
rx_descriptor->BTCNT.reg = beat_length;
rx_descriptor->SRCADDR.reg = ((uint32_t) src);
#ifdef SAMD51
if (peripheral == QSPI) {
rx_descriptor->SRCADDR.reg = ((uint32_t) src + length);
}
#endif
rx_descriptor->DSTADDR.reg = ((uint32_t)buffer_in + length);
rx_descriptor->BTCTRL.bit.VALID = true;
}
// Set up TX second.
if (tx_active) {
DmacDescriptor* tx_descriptor = &dma_descriptors[SHARED_TX_CHANNEL];
tx_descriptor->BTCTRL.reg = beat_size;
tx_descriptor->BTCNT.reg = beat_length;
if (buffer_out != NULL) {
tx_descriptor->SRCADDR.reg = ((uint32_t)buffer_out + length);
tx_descriptor->BTCTRL.reg |= DMAC_BTCTRL_SRCINC;
} else {
tx_descriptor->SRCADDR.reg = ((uint32_t) &tx);
}
tx_descriptor->DSTADDR.reg = ((uint32_t) dest);
tx_descriptor->BTCTRL.bit.VALID = true;
}
if (sercom) {
SercomSpi *s = &((Sercom*) peripheral)->SPI;
s->INTFLAG.reg = SERCOM_SPI_INTFLAG_RXC | SERCOM_SPI_INTFLAG_DRE;
} else {
//QSPI->INTFLAG.reg = QSPI_INTFLAG_RXC | QSPI_INTFLAG_DRE;
}
// Start the RX job first so we don't miss the first byte. The TX job clocks
// the output.
if (rx_active) {
dma_enable_channel(SHARED_RX_CHANNEL);
}
if (tx_active) {
dma_enable_channel(SHARED_TX_CHANNEL);
}
if (sercom) {
//DMAC->SWTRIGCTRL.reg |= (1 << SHARED_TX_CHANNEL);
} else {
// Do a manual copy to trigger then DMA. We do 32-bit accesses to match the DMA.
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wcast-align"
if (rx_active) {
//buffer_in[0] = *src;
DMAC->SWTRIGCTRL.reg |= (1 << SHARED_RX_CHANNEL);
} else {
//*(uint32_t*)dest = ((uint32_t*) buffer_out)[0];
}
#pragma GCC diagnostic pop
}
// Channels cycle between Suspend -> Pending -> Busy and back while transfering. So, we check
// the channels transfer status for an error or completion.
if (rx_active) {
while ((dma_transfer_status(SHARED_RX_CHANNEL) & 0x3) == 0) {}
}
if (tx_active) {
while ((dma_transfer_status(SHARED_TX_CHANNEL) & 0x3) == 0) {}
}
if (sercom) {
Sercom* s = (Sercom*) peripheral;
// Wait for the SPI transfer to complete.
while (s->SPI.INTFLAG.bit.TXC == 0) {}
// This transmit will cause the RX buffer overflow but we're OK with that.
// So, read the garbage and clear the overflow flag.
if (!rx_active) {
while (s->SPI.INTFLAG.bit.RXC == 1) {
s->SPI.DATA.reg;
}
s->SPI.STATUS.bit.BUFOVF = 1;
s->SPI.INTFLAG.reg = SERCOM_SPI_INTFLAG_ERROR;
}
}
if ((!rx_active || dma_transfer_status(SHARED_RX_CHANNEL) == DMAC_CHINTFLAG_TCMPL) &&
(!tx_active || dma_transfer_status(SHARED_TX_CHANNEL) == DMAC_CHINTFLAG_TCMPL)) {
return length;
}
return -2;
}
int32_t sercom_dma_transfer(Sercom* sercom, const uint8_t* buffer_out, uint8_t* buffer_in,
uint32_t length) {
return shared_dma_transfer(sercom, buffer_out, &sercom->SPI.DATA.reg, &sercom->SPI.DATA.reg, buffer_in, length, 0);
}
int32_t sercom_dma_write(Sercom* sercom, const uint8_t* buffer, uint32_t length) {
return shared_dma_transfer(sercom, buffer, &sercom->SPI.DATA.reg, NULL, NULL, length, 0);
}
int32_t sercom_dma_read(Sercom* sercom, uint8_t* buffer, uint32_t length, uint8_t tx) {
return shared_dma_transfer(sercom, NULL, &sercom->SPI.DATA.reg, &sercom->SPI.DATA.reg, buffer, length, tx);
}
#ifdef SAMD51
int32_t qspi_dma_write(uint32_t address, const uint8_t* buffer, uint32_t length) {
return shared_dma_transfer(QSPI, buffer, (uint32_t*) (QSPI_AHB + address), NULL, NULL, length, 0);
}
int32_t qspi_dma_read(uint32_t address, uint8_t* buffer, uint32_t length) {
return shared_dma_transfer(QSPI, NULL, NULL, (uint32_t*) (QSPI_AHB + address), buffer, length, 0);
}
#endif
DmacDescriptor* dma_descriptor(uint8_t channel_number) {
return &dma_descriptors[channel_number];
}
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