Revision 0:6242d93d3c51, committed 2015-11-10

Comitter:

manitou

Date:

Tue Nov 10 12:07:03 2015 +0000

Commit message:

DMA SPI proof of concept, wire speed 44.3 mbs

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Tue Nov 10 12:07:03 2015 +0000
@@ -0,0 +1,119 @@
+//nucleo DMA SPI from pyboard SPI   proof of concept
+// need DMA channel for TX and another for RX
+//tx DMA2_Stream5, DMA_CHANNEL_3   rx DMA2_Stream2, DMA_CHANNEL_3
+// SPI1 and 4 max 45mbs    SPI3 4  max 22.5mbs
+#include "mbed.h"
+
+#define PRREG(z) printf(#z" 0x%x\n",z)
+Timer tmr;
+DigitalOut CSpin(D10);
+SPI spi(SPI_MOSI, SPI_MISO, SPI_SCK); // mosi, miso, sclk  SPI1
+
+#define SPI_BUFF_SIZE 1024
+uint8_t rx_buffer[SPI_BUFF_SIZE];
+uint8_t tx_buffer[SPI_BUFF_SIZE];
+
+void spiperf(int mhz) {
+    int i, us;
+
+    spi.frequency(mhz*1000000);
+    CSpin=0;
+    us = tmr.read_us();
+    for(i=0;i<SPI_BUFF_SIZE;i++) spi.write(tx_buffer[i]);
+    us = tmr.read_us()-us;
+    CSpin=1;
+    printf("spi %d mhz %d us %.2f mbs  %0x\n",mhz,us,8.*SPI_BUFF_SIZE/us,SPI1->CR1);
+}
+
+// need to re-create SPI firmware to access SPI handle
+static SPI_HandleTypeDef SpiHandle;
+  
+static void spiInit() {
+    SpiHandle.Instance = SPI1;
+
+    __HAL_SPI_DISABLE(&SpiHandle);
+
+    SpiHandle.Init.Mode              = SPI_MODE_MASTER;
+    SpiHandle.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_16;  // 2 is 45 mhz    32 is 2.81mhz
+    SpiHandle.Init.Direction         = SPI_DIRECTION_2LINES;
+    SpiHandle.Init.CLKPhase          = SPI_PHASE_1EDGE;  // mode 0
+    SpiHandle.Init.CLKPolarity       = SPI_POLARITY_LOW;
+    SpiHandle.Init.CRCCalculation    = SPI_CRCCALCULATION_DISABLED;
+    SpiHandle.Init.CRCPolynomial     = 7;
+    SpiHandle.Init.DataSize          = SPI_DATASIZE_8BIT;
+    SpiHandle.Init.FirstBit          = SPI_FIRSTBIT_MSB;
+    SpiHandle.Init.NSS               = SPI_NSS_SOFT;
+    SpiHandle.Init.TIMode            = SPI_TIMODE_DISABLED;
+
+    if (HAL_SPI_Init(&SpiHandle) != HAL_OK) {
+        error("Cannot initialize SPI");
+    }
+
+    __HAL_SPI_ENABLE(&SpiHandle);
+}
+
+DMA_HandleTypeDef tx_DMA_Handle, rx_DMA_Handle;
+
+static void dmaInit() {
+    __DMA2_CLK_ENABLE();
+    tx_DMA_Handle.Instance = DMA2_Stream5;
+
+    // Need to deinit DMA first
+    tx_DMA_Handle.State = HAL_DMA_STATE_READY;
+    HAL_DMA_DeInit(&tx_DMA_Handle);
+
+    tx_DMA_Handle.Init.Channel = DMA_CHANNEL_3;
+    tx_DMA_Handle.Init.Direction = DMA_MEMORY_TO_PERIPH;
+    tx_DMA_Handle.Init.PeriphInc = DMA_PINC_DISABLE;
+    tx_DMA_Handle.Init.MemInc = DMA_MINC_ENABLE;
+    tx_DMA_Handle.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
+    tx_DMA_Handle.Init.MemDataAlignment = DMA_MDATAALIGN_BYTE;
+    tx_DMA_Handle.Init.Mode = DMA_NORMAL;
+    tx_DMA_Handle.Init.Priority = DMA_PRIORITY_LOW;
+    tx_DMA_Handle.Init.FIFOMode = DMA_FIFOMODE_DISABLE;
+    tx_DMA_Handle.Init.FIFOThreshold = DMA_FIFO_THRESHOLD_FULL;
+    tx_DMA_Handle.Init.MemBurst = DMA_MBURST_INC4;
+    tx_DMA_Handle.Init.PeriphBurst = DMA_PBURST_INC4;
+    HAL_DMA_Init(&tx_DMA_Handle);
+    //__HAL_LINKDMA(spiHandle, DMA_Handle, tx_DMA_Handle);   // TODO macro
+    tx_DMA_Handle.Parent = &SpiHandle;
+    SpiHandle.hdmatx = &tx_DMA_Handle;
+    SpiHandle.hdmarx = NULL;
+}
+
+
+static void  spiSend(uint8_t *data, uint16_t bytes) {
+    // ? need SPI handle
+    HAL_SPI_Transmit_DMA(&SpiHandle, data, bytes);  // TODO
+    HAL_DMA_PollForTransfer(&tx_DMA_Handle, HAL_DMA_FULL_TRANSFER , 2000);
+    // while (tx_DMA_Handle.Instance->CR & DMA_SxCR_EN);   // spin
+}
+  
+int main() {
+    uint32_t us, i;
+    
+    printf("SystemCoreClock %d  %s %s\n",SystemCoreClock,__TIME__,__DATE__);
+    tmr.start();
+    CSpin =1;
+    for(i=0;i<SPI_BUFF_SIZE;i++) tx_buffer[i]=i;
+    PRREG(SPI1->CR1);
+    PRREG(SPI1->CR2);
+    PRREG(SPI1->SR);
+
+    spiperf(1);
+    spiperf(2);
+    spiperf(4);
+    spiperf(8);
+    spiperf(15);
+    spiperf(30);
+    spiperf(45);
+
+    spiInit();
+    dmaInit();
+    CSpin = 0;
+    us = tmr.read_us();
+    spiSend(tx_buffer,SPI_BUFF_SIZE);
+    us = tmr.read_us()-us;
+    CSpin=1;
+    printf("DMAspi  %d us %.2f mbs  %0x\n",us,8.*SPI_BUFF_SIZE/us,SPI1->CR1);
+}
\ No newline at end of file

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed.bld	Tue Nov 10 12:07:03 2015 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/mbed_official/code/mbed/builds/9296ab0bfc11
\ No newline at end of file