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Diff: targets/TARGET_NUVOTON/TARGET_NUC472/spi_api.c
- Revision:
- 0:f269e3021894
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/TARGET_NUVOTON/TARGET_NUC472/spi_api.c Sun Oct 23 15:10:02 2016 +0000 @@ -0,0 +1,768 @@ +/* mbed Microcontroller Library + * Copyright (c) 2015-2016 Nuvoton + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "spi_api.h" + +#if DEVICE_SPI + +#include "cmsis.h" +#include "pinmap.h" +#include "PeripheralPins.h" +#include "nu_modutil.h" +#include "nu_miscutil.h" +#include "nu_bitutil.h" + +#if DEVICE_SPI_ASYNCH +#include "dma_api.h" +#include "dma.h" +#endif + +#define NU_SPI_FRAME_MIN 8 +#define NU_SPI_FRAME_MAX 32 +#define NU_SPI_FIFO_DEPTH 8 + +struct nu_spi_var { +#if DEVICE_SPI_ASYNCH + uint8_t pdma_perp_tx; + uint8_t pdma_perp_rx; +#endif +}; + +static struct nu_spi_var spi0_var = { +#if DEVICE_SPI_ASYNCH + .pdma_perp_tx = PDMA_SPI0_TX, + .pdma_perp_rx = PDMA_SPI0_RX +#endif +}; +static struct nu_spi_var spi1_var = { +#if DEVICE_SPI_ASYNCH + .pdma_perp_tx = PDMA_SPI1_TX, + .pdma_perp_rx = PDMA_SPI1_RX +#endif +}; +static struct nu_spi_var spi2_var = { +#if DEVICE_SPI_ASYNCH + .pdma_perp_tx = PDMA_SPI2_TX, + .pdma_perp_rx = PDMA_SPI2_RX +#endif +}; +static struct nu_spi_var spi3_var = { +#if DEVICE_SPI_ASYNCH + .pdma_perp_tx = PDMA_SPI3_TX, + .pdma_perp_rx = PDMA_SPI3_RX +#endif +}; + +#if DEVICE_SPI_ASYNCH +static void spi_enable_vector_interrupt(spi_t *obj, uint32_t handler, uint8_t enable); +static void spi_master_enable_interrupt(spi_t *obj, uint8_t enable); +static uint32_t spi_master_write_asynch(spi_t *obj, uint32_t tx_limit); +static uint32_t spi_master_read_asynch(spi_t *obj); +static uint32_t spi_event_check(spi_t *obj); +static void spi_enable_event(spi_t *obj, uint32_t event, uint8_t enable); +static void spi_buffer_set(spi_t *obj, const void *tx, size_t tx_length, void *rx, size_t rx_length); +static void spi_check_dma_usage(DMAUsage *dma_usage, int *dma_ch_tx, int *dma_ch_rx); +static uint8_t spi_get_data_width(spi_t *obj); +static int spi_is_tx_complete(spi_t *obj); +static int spi_is_rx_complete(spi_t *obj); +static int spi_writeable(spi_t * obj); +static int spi_readable(spi_t * obj); +static void spi_dma_handler_tx(uint32_t id, uint32_t event_dma); +static void spi_dma_handler_rx(uint32_t id, uint32_t event_dma); +#endif + +static uint32_t spi_modinit_mask = 0; + +static const struct nu_modinit_s spi_modinit_tab[] = { + {SPI_0, SPI0_MODULE, 0, 0, SPI0_RST, SPI0_IRQn, &spi0_var}, + {SPI_1, SPI1_MODULE, 0, 0, SPI1_RST, SPI1_IRQn, &spi1_var}, + {SPI_2, SPI2_MODULE, 0, 0, SPI2_RST, SPI2_IRQn, &spi2_var}, + {SPI_3, SPI3_MODULE, 0, 0, SPI3_RST, SPI3_IRQn, &spi3_var}, + + {NC, 0, 0, 0, 0, (IRQn_Type) 0, NULL} +}; + +void spi_init(spi_t *obj, PinName mosi, PinName miso, PinName sclk, PinName ssel) { + // Determine which SPI_x the pins are used for + uint32_t spi_mosi = pinmap_peripheral(mosi, PinMap_SPI_MOSI); + uint32_t spi_miso = pinmap_peripheral(miso, PinMap_SPI_MISO); + uint32_t spi_sclk = pinmap_peripheral(sclk, PinMap_SPI_SCLK); + uint32_t spi_ssel = pinmap_peripheral(ssel, PinMap_SPI_SSEL); + uint32_t spi_data = pinmap_merge(spi_mosi, spi_miso); + uint32_t spi_cntl = pinmap_merge(spi_sclk, spi_ssel); + obj->spi.spi = (SPIName) pinmap_merge(spi_data, spi_cntl); + MBED_ASSERT((int)obj->spi.spi != NC); + + const struct nu_modinit_s *modinit = get_modinit(obj->spi.spi, spi_modinit_tab); + MBED_ASSERT(modinit != NULL); + MBED_ASSERT(modinit->modname == obj->spi.spi); + + // Reset this module + SYS_ResetModule(modinit->rsetidx); + + // Enable IP clock + CLK_EnableModuleClock(modinit->clkidx); + + //SPI_T *spi_base = (SPI_T *) NU_MODBASE(obj->spi.spi); + + pinmap_pinout(mosi, PinMap_SPI_MOSI); + pinmap_pinout(miso, PinMap_SPI_MISO); + pinmap_pinout(sclk, PinMap_SPI_SCLK); + pinmap_pinout(ssel, PinMap_SPI_SSEL); + + obj->spi.pin_mosi = mosi; + obj->spi.pin_miso = miso; + obj->spi.pin_sclk = sclk; + obj->spi.pin_ssel = ssel; + + // Configure the SPI data format and frequency + //spi_format(obj, 8, 0, SPI_MSB); // 8 bits, mode 0 + //spi_frequency(obj, 1000000); + +#if DEVICE_SPI_ASYNCH + obj->spi.dma_usage = DMA_USAGE_NEVER; + obj->spi.event = 0; + obj->spi.dma_chn_id_tx = DMA_ERROR_OUT_OF_CHANNELS; + obj->spi.dma_chn_id_rx = DMA_ERROR_OUT_OF_CHANNELS; +#endif + + // Mark this module to be inited. + int i = modinit - spi_modinit_tab; + spi_modinit_mask |= 1 << i; +} + +void spi_free(spi_t *obj) +{ +#if DEVICE_SPI_ASYNCH + if (obj->spi.dma_chn_id_tx != DMA_ERROR_OUT_OF_CHANNELS) { + dma_channel_free(obj->spi.dma_chn_id_tx); + obj->spi.dma_chn_id_tx = DMA_ERROR_OUT_OF_CHANNELS; + } + if (obj->spi.dma_chn_id_rx != DMA_ERROR_OUT_OF_CHANNELS) { + dma_channel_free(obj->spi.dma_chn_id_rx); + obj->spi.dma_chn_id_rx = DMA_ERROR_OUT_OF_CHANNELS; + } +#endif + + SPI_Close((SPI_T *) NU_MODBASE(obj->spi.spi)); + + const struct nu_modinit_s *modinit = get_modinit(obj->spi.spi, spi_modinit_tab); + MBED_ASSERT(modinit != NULL); + MBED_ASSERT(modinit->modname == obj->spi.spi); + + SPI_DisableInt(((SPI_T *) NU_MODBASE(obj->spi.spi)), (SPI_FIFO_RXOVIEN_MASK | SPI_FIFO_RXTHIEN_MASK | SPI_FIFO_TXTHIEN_MASK)); + NVIC_DisableIRQ(modinit->irq_n); + + // Disable IP clock + CLK_DisableModuleClock(modinit->clkidx); + + //((struct nu_spi_var *) modinit->var)->obj = NULL; + + // Mark this module to be deinited. + int i = modinit - spi_modinit_tab; + spi_modinit_mask &= ~(1 << i); +} +void spi_format(spi_t *obj, int bits, int mode, int slave) +{ + MBED_ASSERT(bits >= NU_SPI_FRAME_MIN && bits <= NU_SPI_FRAME_MAX); + + SPI_T *spi_base = (SPI_T *) NU_MODBASE(obj->spi.spi); + + // NOTE 1: All configurations should be ready before enabling SPI peripheral. + // NOTE 2: Re-configuration is allowed only as SPI peripheral is idle. + while (SPI_IS_BUSY(spi_base)); + SPI_DISABLE(spi_base); + + SPI_Open(spi_base, + slave ? SPI_SLAVE : SPI_MASTER, + (mode == 0) ? SPI_MODE_0 : (mode == 1) ? SPI_MODE_1 : (mode == 2) ? SPI_MODE_2 : SPI_MODE_3, + bits, + SPI_GetBusClock(spi_base)); + // NOTE: Hardcode to be MSB first. + SPI_SET_MSB_FIRST(spi_base); + + if (! slave) { + // Master + if (obj->spi.pin_ssel != NC) { + // Configure SS as low active. + SPI_EnableAutoSS(spi_base, SPI_SS0, SPI_SS_ACTIVE_LOW); + // NOTE: In NUC472 series, all SPI SS pins are SS0, so we can hardcode SS0 here. + } + else { + SPI_DisableAutoSS(spi_base); + } + } + else { + // Slave + // Configure SS as low active. + spi_base->SSCTL &= ~SPI_SSCTL_SSACTPOL_Msk; + // NOTE: SPI_SS0 is defined as the slave select input in Slave mode. + } +} + +void spi_frequency(spi_t *obj, int hz) +{ + SPI_T *spi_base = (SPI_T *) NU_MODBASE(obj->spi.spi); + + while (SPI_IS_BUSY(spi_base)); + SPI_DISABLE(spi_base); + + SPI_SetBusClock((SPI_T *) NU_MODBASE(obj->spi.spi), hz); +} + + +int spi_master_write(spi_t *obj, int value) +{ + SPI_T *spi_base = (SPI_T *) NU_MODBASE(obj->spi.spi); + + // NOTE: Data in receive FIFO can be read out via ICE. + SPI_ENABLE(spi_base); + + // Wait for tx buffer empty + while(! spi_writeable(obj)); + SPI_WRITE_TX(spi_base, value); + + // Wait for rx buffer full + while (! spi_readable(obj)); + int value2 = SPI_READ_RX(spi_base); + + SPI_DISABLE(spi_base); + + return value2; +} + +#if DEVICE_SPISLAVE +int spi_slave_receive(spi_t *obj) +{ + SPI_T *spi_base = (SPI_T *) NU_MODBASE(obj->spi.spi); + + SPI_ENABLE(spi_base); + + return spi_readable(obj); +}; + +int spi_slave_read(spi_t *obj) +{ + SPI_T *spi_base = (SPI_T *) NU_MODBASE(obj->spi.spi); + + SPI_ENABLE(spi_base); + + // Wait for rx buffer full + while (! spi_readable(obj)); + int value = SPI_READ_RX(spi_base); + return value; +} + +void spi_slave_write(spi_t *obj, int value) +{ + SPI_T *spi_base = (SPI_T *) NU_MODBASE(obj->spi.spi); + + SPI_ENABLE(spi_base); + + // Wait for tx buffer empty + while(! spi_writeable(obj)); + SPI_WRITE_TX(spi_base, value); +} +#endif + +#if DEVICE_SPI_ASYNCH +void spi_master_transfer(spi_t *obj, const void *tx, size_t tx_length, void *rx, size_t rx_length, uint8_t bit_width, uint32_t handler, uint32_t event, DMAUsage hint) +{ + //MBED_ASSERT(bits >= NU_SPI_FRAME_MIN && bits <= NU_SPI_FRAME_MAX); + SPI_T *spi_base = (SPI_T *) NU_MODBASE(obj->spi.spi); + SPI_SET_DATA_WIDTH(spi_base, bit_width); + + obj->spi.dma_usage = hint; + spi_check_dma_usage(&obj->spi.dma_usage, &obj->spi.dma_chn_id_tx, &obj->spi.dma_chn_id_rx); + uint32_t data_width = spi_get_data_width(obj); + // Conditions to go DMA way: + // (1) No DMA support for non-8 multiple data width. + // (2) tx length >= rx length. Otherwise, as tx DMA is done, no bus activity for remaining rx. + if ((data_width % 8) || + (tx_length < rx_length)) { + obj->spi.dma_usage = DMA_USAGE_NEVER; + dma_channel_free(obj->spi.dma_chn_id_tx); + obj->spi.dma_chn_id_tx = DMA_ERROR_OUT_OF_CHANNELS; + dma_channel_free(obj->spi.dma_chn_id_rx); + obj->spi.dma_chn_id_rx = DMA_ERROR_OUT_OF_CHANNELS; + } + + // SPI IRQ is necessary for both interrupt way and DMA way + spi_enable_event(obj, event, 1); + spi_buffer_set(obj, tx, tx_length, rx, rx_length); + + SPI_ENABLE(spi_base); + + if (obj->spi.dma_usage == DMA_USAGE_NEVER) { + // Interrupt way + spi_master_write_asynch(obj, NU_SPI_FIFO_DEPTH / 2); + spi_enable_vector_interrupt(obj, handler, 1); + spi_master_enable_interrupt(obj, 1); + } else { + // DMA way + const struct nu_modinit_s *modinit = get_modinit(obj->spi.spi, spi_modinit_tab); + MBED_ASSERT(modinit != NULL); + MBED_ASSERT(modinit->modname == obj->spi.spi); + + // Configure tx DMA + PDMA->CHCTL |= 1 << obj->spi.dma_chn_id_tx; // Enable this DMA channel + PDMA_SetTransferMode(obj->spi.dma_chn_id_tx, + ((struct nu_spi_var *) modinit->var)->pdma_perp_tx, // Peripheral connected to this PDMA + 0, // Scatter-gather disabled + 0); // Scatter-gather descriptor address + PDMA_SetTransferCnt(obj->spi.dma_chn_id_tx, + (data_width == 8) ? PDMA_WIDTH_8 : (data_width == 16) ? PDMA_WIDTH_16 : PDMA_WIDTH_32, + tx_length); + PDMA_SetTransferAddr(obj->spi.dma_chn_id_tx, + ((uint32_t) tx) + (data_width / 8) * tx_length, // NOTE: End of source address + PDMA_SAR_INC, // Source address incremental + (uint32_t) &spi_base->TX, // Destination address + PDMA_DAR_FIX); // Destination address fixed + PDMA_SetBurstType(obj->spi.dma_chn_id_tx, + PDMA_REQ_SINGLE, // Single mode + 0); // Burst size + PDMA_EnableInt(obj->spi.dma_chn_id_tx, + 0); // Interrupt type. No use here + // Register DMA event handler + dma_set_handler(obj->spi.dma_chn_id_tx, (uint32_t) spi_dma_handler_tx, (uint32_t) obj, DMA_EVENT_ALL); + + // Configure rx DMA + PDMA->CHCTL |= 1 << obj->spi.dma_chn_id_rx; // Enable this DMA channel + PDMA_SetTransferMode(obj->spi.dma_chn_id_rx, + ((struct nu_spi_var *) modinit->var)->pdma_perp_rx, // Peripheral connected to this PDMA + 0, // Scatter-gather disabled + 0); // Scatter-gather descriptor address + PDMA_SetTransferCnt(obj->spi.dma_chn_id_rx, + (data_width == 8) ? PDMA_WIDTH_8 : (data_width == 16) ? PDMA_WIDTH_16 : PDMA_WIDTH_32, + rx_length); + PDMA_SetTransferAddr(obj->spi.dma_chn_id_rx, + (uint32_t) &spi_base->RX, // Source address + PDMA_SAR_FIX, // Source address fixed + ((uint32_t) rx) + (data_width / 8) * rx_length, // NOTE: End of destination address + PDMA_DAR_INC); // Destination address incremental + PDMA_SetBurstType(obj->spi.dma_chn_id_rx, + PDMA_REQ_SINGLE, // Single mode + 0); // Burst size + PDMA_EnableInt(obj->spi.dma_chn_id_rx, + 0); // Interrupt type. No use here + // Register DMA event handler + dma_set_handler(obj->spi.dma_chn_id_rx, (uint32_t) spi_dma_handler_rx, (uint32_t) obj, DMA_EVENT_ALL); + + // Start tx/rx DMA transfer + spi_enable_vector_interrupt(obj, handler, 1); + // NOTE: It is safer to start rx DMA first and then tx DMA. Otherwise, receive FIFO is subject to overflow by tx DMA. + SPI_TRIGGER_RX_PDMA(((SPI_T *) NU_MODBASE(obj->spi.spi))); + SPI_TRIGGER_TX_PDMA(((SPI_T *) NU_MODBASE(obj->spi.spi))); + spi_master_enable_interrupt(obj, 1); + } +} + +/** + * Abort an SPI transfer + * This is a helper function for event handling. When any of the events listed occurs, the HAL will abort any ongoing + * transfers + * @param[in] obj The SPI peripheral to stop + */ +void spi_abort_asynch(spi_t *obj) +{ + SPI_T *spi_base = (SPI_T *) NU_MODBASE(obj->spi.spi); + + if (obj->spi.dma_usage != DMA_USAGE_NEVER) { + // Receive FIFO Overrun in case of tx length > rx length on DMA way + if (spi_base->STATUS & SPI_STATUS_RXOVIF_Msk) { + spi_base->STATUS = SPI_STATUS_RXOVIF_Msk; + } + + if (obj->spi.dma_chn_id_tx != DMA_ERROR_OUT_OF_CHANNELS) { + PDMA_DisableInt(obj->spi.dma_chn_id_tx, 0); + // FIXME: Next PDMA transfer will fail with PDMA_STOP() called. Cause is unknown. + //PDMA_STOP(obj->spi.dma_chn_id_tx); + PDMA->CHCTL &= ~(1 << obj->spi.dma_chn_id_tx); + } + SPI_DISABLE_TX_PDMA(((SPI_T *) NU_MODBASE(obj->spi.spi))); + + if (obj->spi.dma_chn_id_rx != DMA_ERROR_OUT_OF_CHANNELS) { + PDMA_DisableInt(obj->spi.dma_chn_id_rx, 0); + // FIXME: Next PDMA transfer will fail with PDMA_STOP() called. Cause is unknown. + //PDMA_STOP(obj->spi.dma_chn_id_rx); + PDMA->CHCTL &= ~(1 << obj->spi.dma_chn_id_rx); + } + SPI_DISABLE_RX_PDMA(((SPI_T *) NU_MODBASE(obj->spi.spi))); + } + + // Necessary for both interrupt way and DMA way + spi_enable_vector_interrupt(obj, 0, 0); + spi_master_enable_interrupt(obj, 0); + + // FIXME: SPI H/W may get out of state without the busy check. + while (SPI_IS_BUSY(spi_base)); + SPI_DISABLE(spi_base); + + SPI_ClearRxFIFO(spi_base); + SPI_ClearTxFIFO(spi_base); +} + +/** + * Handle the SPI interrupt + * Read frames until the RX FIFO is empty. Write at most as many frames as were read. This way, + * it is unlikely that the RX FIFO will overflow. + * @param[in] obj The SPI peripheral that generated the interrupt + * @return + */ +uint32_t spi_irq_handler_asynch(spi_t *obj) +{ + // Check for SPI events + uint32_t event = spi_event_check(obj); + if (event) { + spi_abort_asynch(obj); + } + + return (obj->spi.event & event) | ((event & SPI_EVENT_COMPLETE) ? SPI_EVENT_INTERNAL_TRANSFER_COMPLETE : 0); +} + +uint8_t spi_active(spi_t *obj) +{ + SPI_T *spi_base = (SPI_T *) NU_MODBASE(obj->spi.spi); + // FIXME + /* + if ((obj->rx_buff.buffer && obj->rx_buff.pos < obj->rx_buff.length) + || (obj->tx_buff.buffer && obj->tx_buff.pos < obj->tx_buff.length) ){ + return 1; + } else { + // interrupts are disabled, all transaction have been completed + // TODO: checking rx fifo, it reports data eventhough RFDF is not set + return DSPI_HAL_GetIntMode(obj->spi.address, kDspiRxFifoDrainRequest); + }*/ + + //return SPI_IS_BUSY(spi_base); + return (spi_base->CTL & SPI_CTL_SPIEN_Msk); +} + +int spi_allow_powerdown(void) +{ + uint32_t modinit_mask = spi_modinit_mask; + while (modinit_mask) { + int spi_idx = nu_ctz(modinit_mask); + const struct nu_modinit_s *modinit = spi_modinit_tab + spi_idx; + if (modinit->modname != NC) { + SPI_T *spi_base = (SPI_T *) NU_MODBASE(modinit->modname); + // Disallow entering power-down mode if SPI transfer is enabled. + if (spi_base->CTL & SPI_CTL_SPIEN_Msk) { + return 0; + } + } + modinit_mask &= ~(1 << spi_idx); + } + + return 1; +} + +static int spi_writeable(spi_t * obj) +{ + // Receive FIFO must not be full to avoid receive FIFO overflow on next transmit/receive + //return (! SPI_GET_TX_FIFO_FULL_FLAG(((SPI_T *) NU_MODBASE(obj->spi.spi)))) && (SPI_GET_RX_FIFO_COUNT(((SPI_T *) NU_MODBASE(obj->spi.spi))) < NU_SPI_FIFO_DEPTH); + return (! SPI_GET_TX_FIFO_FULL_FLAG(((SPI_T *) NU_MODBASE(obj->spi.spi)))); +} + +static int spi_readable(spi_t * obj) +{ + return ! SPI_GET_RX_FIFO_EMPTY_FLAG(((SPI_T *) NU_MODBASE(obj->spi.spi))); +} + +static void spi_enable_event(spi_t *obj, uint32_t event, uint8_t enable) +{ + obj->spi.event &= ~SPI_EVENT_ALL; + obj->spi.event |= (event & SPI_EVENT_ALL); + if (event & SPI_EVENT_RX_OVERFLOW) { + SPI_EnableInt((SPI_T *) NU_MODBASE(obj->spi.spi), SPI_FIFO_RXOVIEN_MASK); + } +} + +static void spi_enable_vector_interrupt(spi_t *obj, uint32_t handler, uint8_t enable) +{ + const struct nu_modinit_s *modinit = get_modinit(obj->spi.spi, spi_modinit_tab); + MBED_ASSERT(modinit != NULL); + MBED_ASSERT(modinit->modname == obj->spi.spi); + + if (enable) { + NVIC_SetVector(modinit->irq_n, handler); + NVIC_EnableIRQ(modinit->irq_n); + } + else { + //NVIC_SetVector(modinit->irq_n, handler); + NVIC_DisableIRQ(modinit->irq_n); + } +} + +static void spi_master_enable_interrupt(spi_t *obj, uint8_t enable) +{ + SPI_T *spi_base = (SPI_T *) NU_MODBASE(obj->spi.spi); + + if (enable) { + SPI_SetFIFOThreshold(spi_base, 4, 4); + //SPI_SET_SUSPEND_CYCLE(spi_base, 4); + // Enable tx/rx FIFO threshold interrupt + SPI_EnableInt(spi_base, SPI_FIFO_RXTHIEN_MASK | SPI_FIFO_TXTHIEN_MASK); + } + else { + SPI_DisableInt(spi_base, SPI_FIFO_RXTHIEN_MASK | SPI_FIFO_TXTHIEN_MASK); + } +} + +static uint32_t spi_event_check(spi_t *obj) +{ + SPI_T *spi_base = (SPI_T *) NU_MODBASE(obj->spi.spi); + uint32_t event = 0; + + if (obj->spi.dma_usage == DMA_USAGE_NEVER) { + uint32_t n_rec = spi_master_read_asynch(obj); + spi_master_write_asynch(obj, n_rec); + } + + if (spi_is_tx_complete(obj) && spi_is_rx_complete(obj)) { + event |= SPI_EVENT_COMPLETE; + } + + // Receive FIFO Overrun + if (spi_base->STATUS & SPI_STATUS_RXOVIF_Msk) { + spi_base->STATUS = SPI_STATUS_RXOVIF_Msk; + // In case of tx length > rx length on DMA way + if (obj->spi.dma_usage == DMA_USAGE_NEVER) { + event |= SPI_EVENT_RX_OVERFLOW; + } + } + + // Receive Time-Out + if (spi_base->STATUS & SPI_STATUS_RXTOIF_Msk) { + spi_base->STATUS = SPI_STATUS_RXTOIF_Msk; + //event |= SPI_EVENT_ERROR; + } + // Transmit FIFO Under-Run + if (spi_base->STATUS & SPI_STATUS_TXUFIF_Msk) { + spi_base->STATUS = SPI_STATUS_TXUFIF_Msk; + event |= SPI_EVENT_ERROR; + } + + return event; +} + +/** + * Send words from the SPI TX buffer until the send limit is reached or the TX FIFO is full + * tx_limit is provided to ensure that the number of SPI frames (words) in flight can be managed. + * @param[in] obj The SPI object on which to operate + * @param[in] tx_limit The maximum number of words to send + * @return The number of SPI words that have been transfered + */ +static uint32_t spi_master_write_asynch(spi_t *obj, uint32_t tx_limit) +{ + uint32_t n_words = 0; + uint32_t tx_rmn = obj->tx_buff.length - obj->tx_buff.pos; + uint32_t rx_rmn = obj->rx_buff.length - obj->rx_buff.pos; + uint32_t max_tx = NU_MAX(tx_rmn, rx_rmn); + max_tx = NU_MIN(max_tx, tx_limit); + uint8_t data_width = spi_get_data_width(obj); + uint8_t bytes_per_word = (data_width + 7) / 8; + uint8_t *tx = (uint8_t *)(obj->tx_buff.buffer) + bytes_per_word * obj->tx_buff.pos; + SPI_T *spi_base = (SPI_T *) NU_MODBASE(obj->spi.spi); + + while ((n_words < max_tx) && spi_writeable(obj)) { + if (spi_is_tx_complete(obj)) { + // Transmit dummy as transmit buffer is empty + SPI_WRITE_TX(spi_base, 0); + } + else { + switch (bytes_per_word) { + case 4: + SPI_WRITE_TX(spi_base, nu_get32_le(tx)); + tx += 4; + break; + case 2: + SPI_WRITE_TX(spi_base, nu_get16_le(tx)); + tx += 2; + break; + case 1: + SPI_WRITE_TX(spi_base, *((uint8_t *) tx)); + tx += 1; + break; + } + + obj->tx_buff.pos ++; + } + n_words ++; + } + + //Return the number of words that have been sent + return n_words; +} + +/** + * Read SPI words out of the RX FIFO + * Continues reading words out of the RX FIFO until the following condition is met: + * o There are no more words in the FIFO + * OR BOTH OF: + * o At least as many words as the TX buffer have been received + * o At least as many words as the RX buffer have been received + * This way, RX overflows are not generated when the TX buffer size exceeds the RX buffer size + * @param[in] obj The SPI object on which to operate + * @return Returns the number of words extracted from the RX FIFO + */ +static uint32_t spi_master_read_asynch(spi_t *obj) +{ + uint32_t n_words = 0; + uint32_t tx_rmn = obj->tx_buff.length - obj->tx_buff.pos; + uint32_t rx_rmn = obj->rx_buff.length - obj->rx_buff.pos; + uint32_t max_rx = NU_MAX(tx_rmn, rx_rmn); + uint8_t data_width = spi_get_data_width(obj); + uint8_t bytes_per_word = (data_width + 7) / 8; + uint8_t *rx = (uint8_t *)(obj->rx_buff.buffer) + bytes_per_word * obj->rx_buff.pos; + SPI_T *spi_base = (SPI_T *) NU_MODBASE(obj->spi.spi); + + while ((n_words < max_rx) && spi_readable(obj)) { + if (spi_is_rx_complete(obj)) { + // Disregard as receive buffer is full + SPI_READ_RX(spi_base); + } + else { + switch (bytes_per_word) { + case 4: { + uint32_t val = SPI_READ_RX(spi_base); + nu_set32_le(rx, val); + rx += 4; + break; + } + case 2: { + uint16_t val = SPI_READ_RX(spi_base); + nu_set16_le(rx, val); + rx += 2; + break; + } + case 1: + *rx ++ = SPI_READ_RX(spi_base); + break; + } + + obj->rx_buff.pos ++; + } + n_words ++; + } + + // Return the number of words received + return n_words; +} + +static void spi_buffer_set(spi_t *obj, const void *tx, size_t tx_length, void *rx, size_t rx_length) +{ + obj->tx_buff.buffer = (void *) tx; + obj->tx_buff.length = tx_length; + obj->tx_buff.pos = 0; + obj->tx_buff.width = spi_get_data_width(obj); + obj->rx_buff.buffer = rx; + obj->rx_buff.length = rx_length; + obj->rx_buff.pos = 0; + obj->rx_buff.width = spi_get_data_width(obj); +} + +static void spi_check_dma_usage(DMAUsage *dma_usage, int *dma_ch_tx, int *dma_ch_rx) +{ + if (*dma_usage != DMA_USAGE_NEVER) { + if (*dma_ch_tx == DMA_ERROR_OUT_OF_CHANNELS) { + *dma_ch_tx = dma_channel_allocate(DMA_CAP_NONE); + } + if (*dma_ch_rx == DMA_ERROR_OUT_OF_CHANNELS) { + *dma_ch_rx = dma_channel_allocate(DMA_CAP_NONE); + } + + if (*dma_ch_tx == DMA_ERROR_OUT_OF_CHANNELS || *dma_ch_rx == DMA_ERROR_OUT_OF_CHANNELS) { + *dma_usage = DMA_USAGE_NEVER; + } + } + + if (*dma_usage == DMA_USAGE_NEVER) { + dma_channel_free(*dma_ch_tx); + *dma_ch_tx = DMA_ERROR_OUT_OF_CHANNELS; + dma_channel_free(*dma_ch_rx); + *dma_ch_rx = DMA_ERROR_OUT_OF_CHANNELS; + } +} + +static uint8_t spi_get_data_width(spi_t *obj) +{ + SPI_T *spi_base = (SPI_T *) NU_MODBASE(obj->spi.spi); + + return ((spi_base->CTL & SPI_CTL_DWIDTH_Msk) >> SPI_CTL_DWIDTH_Pos); +} + +static int spi_is_tx_complete(spi_t *obj) +{ + // ???: Exclude tx fifo empty check due to no such interrupt on DMA way + return (obj->tx_buff.pos == obj->tx_buff.length); + //return (obj->tx_buff.pos == obj->tx_buff.length && SPI_GET_TX_FIFO_EMPTY_FLAG(((SPI_T *) NU_MODBASE(obj->spi.spi)))); +} + +static int spi_is_rx_complete(spi_t *obj) +{ + return (obj->rx_buff.pos == obj->rx_buff.length); +} + +static void spi_dma_handler_tx(uint32_t id, uint32_t event_dma) +{ + spi_t *obj = (spi_t *) id; + + // FIXME: Pass this error to caller + if (event_dma & DMA_EVENT_ABORT) { + } + // Expect SPI IRQ will catch this transfer done event + if (event_dma & DMA_EVENT_TRANSFER_DONE) { + obj->tx_buff.pos = obj->tx_buff.length; + } + // FIXME: Pass this error to caller + if (event_dma & DMA_EVENT_TIMEOUT) { + } + + const struct nu_modinit_s *modinit = get_modinit(obj->spi.spi, spi_modinit_tab); + MBED_ASSERT(modinit != NULL); + MBED_ASSERT(modinit->modname == obj->spi.spi); + + void (*vec)(void) = (void (*)(void)) NVIC_GetVector(modinit->irq_n); + vec(); +} + +static void spi_dma_handler_rx(uint32_t id, uint32_t event_dma) +{ + spi_t *obj = (spi_t *) id; + + // FIXME: Pass this error to caller + if (event_dma & DMA_EVENT_ABORT) { + } + // Expect SPI IRQ will catch this transfer done event + if (event_dma & DMA_EVENT_TRANSFER_DONE) { + obj->rx_buff.pos = obj->rx_buff.length; + } + // FIXME: Pass this error to caller + if (event_dma & DMA_EVENT_TIMEOUT) { + } + + const struct nu_modinit_s *modinit = get_modinit(obj->spi.spi, spi_modinit_tab); + MBED_ASSERT(modinit != NULL); + MBED_ASSERT(modinit->modname == obj->spi.spi); + + void (*vec)(void) = (void (*)(void)) NVIC_GetVector(modinit->irq_n); + vec(); +} + +#endif + +#endif