Diff: targets/TARGET_Silicon_Labs/TARGET_EFM32/dma_api.c

Revision:

149:156823d33999

Parent:

144:ef7eb2e8f9f7

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/targets/TARGET_Silicon_Labs/TARGET_EFM32/dma_api.c	Fri Oct 28 11:17:30 2016 +0100
@@ -0,0 +1,202 @@
+/***************************************************************************//**
+ * @file dma_api.c
+ *******************************************************************************
+ * @section License
+ * <b>(C) Copyright 2015 Silicon Labs, http://www.silabs.com</b>
+ *******************************************************************************
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * 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 <stdint.h>
+#include "dma_api_HAL.h"
+#include "em_device.h"
+#include "em_cmu.h"
+
+#ifdef DMA_PRESENT
+#include "em_dma.h"
+#endif
+
+#ifdef LDMA_PRESENT
+#include "em_ldma.h"
+#endif
+
+/** DMA control block array, requires proper alignment. */
+#ifdef DMA_PRESENT
+#if defined (__ICCARM__)
+#pragma data_alignment=DMACTRL_ALIGNMENT
+DMA_DESCRIPTOR_TypeDef dmaControlBlock[DMACTRL_CH_CNT * 2];
+
+#elif defined (__CC_ARM)
+DMA_DESCRIPTOR_TypeDef dmaControlBlock[DMACTRL_CH_CNT * 2] __attribute__ ((aligned(DMACTRL_ALIGNMENT)));
+
+#elif defined (__GNUC__)
+DMA_DESCRIPTOR_TypeDef dmaControlBlock[DMACTRL_CH_CNT * 2] __attribute__ ((aligned(DMACTRL_ALIGNMENT), section("dma")));
+
+#else
+#error Undefined toolkit, need to define alignment
+#endif
+#endif /* DMA_PRESENT */
+
+uint32_t channels = 0; // Bit vector of taken channels
+bool enabled = false;
+
+void dma_init(void)
+{
+    if (enabled) return;
+
+#if defined DMA_PRESENT
+    CMU_ClockEnable(cmuClock_DMA, true);
+    CMU_ClockEnable(cmuClock_HFPER, true); // FIXME: DMA is clocked via HFCORECLK, why HFPERCLK?
+
+    DMA_Init_TypeDef   dmaInit;
+
+    dmaInit.hprot        = 0;
+    dmaInit.controlBlock = dmaControlBlock;
+    DMA_Init(&dmaInit);
+
+#elif defined LDMA_PRESENT
+    CMU_ClockEnable(cmuClock_LDMA, true);
+
+    LDMA_Init_t ldmaInit;
+
+    ldmaInit.ldmaInitCtrlNumFixed = 0;     /* All channels round-robin */
+    ldmaInit.ldmaInitCtrlSyncPrsClrEn = 0; /* Do not allow PRS to clear SYNCTRIG */
+    ldmaInit.ldmaInitCtrlSyncPrsSetEn = 0; /* Do not allow PRS to set SYNCTRIG */
+    ldmaInit.ldmaInitIrqPriority = 2;      /* IRQ Priority */
+
+    LDMA_Init(&ldmaInit);
+#else
+#error "Unrecognized DMA peripheral"
+#endif
+
+    enabled = true;
+}
+
+int dma_channel_allocate(uint32_t capabilities)
+{
+    int i;
+    // Check if 2d copy is required
+    if (DMA_CAP_2DCOPY & capabilities) {
+        if (channels & 1) {
+            // Channel already in use
+            return DMA_ERROR_OUT_OF_CHANNELS;
+        } else {
+            channels |= 1 << 0;
+            return 0;
+        }
+    }
+    for (i = 1; i < DMA_CHAN_COUNT; i++) {
+        if ((channels & (1 << i)) == 0) {
+            // Channel available
+            channels |= 1 << i;
+            return i;
+        }
+    }
+    // Check if channel 0 is available
+    if ((channels & 1 ) == 0) {
+        channels |= 1 << 0;
+        return 0;
+    }
+    // Couldn't find a channel.
+    return DMA_ERROR_OUT_OF_CHANNELS;
+}
+
+int dma_channel_free(int channelid)
+{
+    if( channelid >= 0 ) {
+        channels &= ~(1 << channelid);
+    }
+
+    return 0;
+}
+
+#ifdef LDMA_PRESENT
+
+/* LDMA emlib API extensions */
+
+typedef struct {
+    LDMAx_CBFunc_t callback;
+    void *userdata;
+} LDMA_InternCallback_t;
+
+static LDMA_InternCallback_t ldmaCallback[DMA_CHAN_COUNT];
+
+void LDMAx_StartTransfer(  int ch,
+                           LDMA_TransferCfg_t *transfer,
+                           LDMA_Descriptor_t  *descriptor,
+                           LDMAx_CBFunc_t cbFunc,
+                           void *userData )
+{
+    ldmaCallback[ch].callback = cbFunc;
+    ldmaCallback[ch].userdata = userData;
+
+    LDMA_StartTransfer(ch, transfer, descriptor);
+}
+
+void LDMA_IRQHandler( void )
+{
+    uint32_t pending, chnum, chmask;
+
+    /* Get all pending and enabled interrupts */
+    pending  = LDMA->IF;
+    pending &= LDMA->IEN;
+
+    /* Check for LDMA error */
+    if ( pending & LDMA_IF_ERROR )
+    {
+        /* Loop here to enable the debugger to see what has happened */
+        while (1)
+            ;
+    }
+
+    /* Iterate over all LDMA channels. */
+    for ( chnum = 0,                chmask = 1;
+          chnum < DMA_CHAN_COUNT;
+          chnum++,                  chmask <<= 1 )
+    {
+        if ( pending & chmask )
+        {
+            /* Clear interrupt flag. */
+            LDMA->IFC = chmask;
+
+            /* Do more stuff here, execute callbacks etc. */
+            if ( ldmaCallback[chnum].callback )
+            {
+                ldmaCallback[chnum].callback(chnum, false, ldmaCallback[chnum].userdata);
+            }
+        }
+    }
+}
+
+/***************************************************************************//**
+ * @brief
+ *   Check if LDMA channel is enabled.
+ *
+ * @param[in] ch
+ *   LDMA channel to check.
+ *
+ * @return
+ *   true if channel is enabled, false if not.
+ ******************************************************************************/
+bool LDMAx_ChannelEnabled( int ch )
+{
+    EFM_ASSERT(ch < DMA_CHAN_COUNT);
+    uint32_t chMask = 1 << ch;
+    return (bool)(LDMA->CHEN & chMask);
+}
+
+#endif /* LDMA_PRESENT */