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Dependents:   STM32_F103-C8T6basecanblink_led

Fork of mbed-dev by mbed official

Revision:
149:156823d33999
Child:
161:2cc1468da177
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/targets/TARGET_NUVOTON/TARGET_M451/dma_api.c	Fri Oct 28 11:17:30 2016 +0100
@@ -0,0 +1,178 @@
+/* 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 "dma_api.h"
+#include "string.h"
+#include "cmsis.h"
+#include "mbed_assert.h"
+#include "PeripheralNames.h"
+#include "nu_modutil.h"
+#include "nu_bitutil.h"
+#include "dma.h"
+
+struct nu_dma_chn_s {
+    void        (*handler)(uint32_t, uint32_t);
+    uint32_t    id;
+    uint32_t    event;
+};
+
+static int dma_inited = 0;
+static uint32_t dma_chn_mask = 0;
+static struct nu_dma_chn_s dma_chn_arr[PDMA_CH_MAX];
+
+static void pdma_vec(void);
+static const struct nu_modinit_s dma_modinit = {DMA_0, PDMA_MODULE, 0, 0, PDMA_RST, PDMA_IRQn, (void *) pdma_vec};
+
+
+void dma_init(void)
+{
+    if (dma_inited) {
+        return;
+    }
+    
+    dma_inited = 1;
+    dma_chn_mask = 0;
+    memset(dma_chn_arr, 0x00, sizeof (dma_chn_arr));
+    
+    // Reset this module
+    SYS_ResetModule(dma_modinit.rsetidx);
+    
+    // Enable IP clock
+    CLK_EnableModuleClock(dma_modinit.clkidx);
+    
+    PDMA_Open(0);
+    
+    NVIC_SetVector(dma_modinit.irq_n, (uint32_t) dma_modinit.var);
+    NVIC_EnableIRQ(dma_modinit.irq_n);
+}
+
+int dma_channel_allocate(uint32_t capabilities)
+{
+    if (! dma_inited) {
+        dma_init();
+    }
+    
+#if 1
+    int i = nu_cto(dma_chn_mask);
+    if (i != 32) {
+         dma_chn_mask |= 1 << i;
+         memset(dma_chn_arr + i, 0x00, sizeof (struct nu_dma_chn_s));
+         return i;
+    }
+#else
+    int i;
+    
+    for (i = 0; i < PDMA_CH_MAX; i ++) {
+        if ((dma_chn_mask & (1 << i)) == 0) {
+            // Channel available
+            dma_chn_mask |= 1 << i;
+            memset(dma_chn_arr + i, 0x00, sizeof (struct nu_dma_chn_s));
+            return i;
+        }
+    }
+#endif
+
+    // No channel available
+    return DMA_ERROR_OUT_OF_CHANNELS;
+}
+
+int dma_channel_free(int channelid)
+{
+    if (channelid != DMA_ERROR_OUT_OF_CHANNELS) {
+        dma_chn_mask &= ~(1 << channelid);
+    }
+    
+    return 0;
+}
+
+void dma_set_handler(int channelid, uint32_t handler, uint32_t id, uint32_t event)
+{
+    MBED_ASSERT(dma_chn_mask & (1 << channelid));
+    
+    dma_chn_arr[channelid].handler = (void (*)(uint32_t, uint32_t)) handler;
+    dma_chn_arr[channelid].id = id;
+    dma_chn_arr[channelid].event = event;
+    
+    // Set interrupt vector if someone has removed it.
+    NVIC_SetVector(dma_modinit.irq_n, (uint32_t) dma_modinit.var);
+    NVIC_EnableIRQ(dma_modinit.irq_n);
+}
+
+static void pdma_vec(void)
+{
+    uint32_t intsts = PDMA_GET_INT_STATUS();
+    
+    // Abort
+    if (intsts & PDMA_INTSTS_ABTIF_Msk) {
+        uint32_t abtsts = PDMA_GET_ABORT_STS();
+        // Clear all Abort flags
+        PDMA_CLR_ABORT_FLAG(abtsts);
+        
+        while (abtsts) {
+            int chn_id = nu_ctz(abtsts);
+            if (dma_chn_mask & (1 << chn_id)) {
+                struct nu_dma_chn_s *dma_chn = dma_chn_arr + chn_id;
+                if (dma_chn->handler && (dma_chn->event & DMA_EVENT_ABORT)) {
+                    dma_chn->handler(dma_chn->id, DMA_EVENT_ABORT);
+                }
+            }
+            abtsts &= ~(1 << chn_id);
+        }
+    }
+    
+    // Transfer done
+    if (intsts & PDMA_INTSTS_TDIF_Msk) {
+        uint32_t tdsts = PDMA_GET_TD_STS();    
+        // Clear all transfer done flags
+        PDMA_CLR_TD_FLAG(tdsts);
+        
+        while (tdsts) {
+            int chn_id = nu_ctz(tdsts);
+            if (dma_chn_mask & (1 << chn_id)) {
+                struct nu_dma_chn_s *dma_chn = dma_chn_arr + chn_id;
+                if (dma_chn->handler && (dma_chn->event & DMA_EVENT_TRANSFER_DONE)) {
+                    dma_chn->handler(dma_chn->id, DMA_EVENT_TRANSFER_DONE);
+                }
+            }
+            tdsts &= ~(1 << chn_id);
+        }
+    }
+    
+    // Table empty
+    if (intsts & PDMA_INTSTS_TEIF_Msk) {
+        uint32_t scatsts = PDMA_GET_EMPTY_STS();    
+        // Clear all table empty flags
+        PDMA_CLR_EMPTY_FLAG(scatsts);
+    }
+    
+    // Timeout
+    uint32_t reqto = intsts & PDMA_INTSTS_REQTOFn_Msk;
+    if (reqto) {
+        // Clear all Timeout flags
+        PDMA->INTSTS = reqto;
+        
+        while (reqto) {
+            int chn_id = nu_ctz(reqto) >> PDMA_INTSTS_REQTOFn_Pos;
+            if (dma_chn_mask & (1 << chn_id)) {
+                struct nu_dma_chn_s *dma_chn = dma_chn_arr + chn_id;
+                if (dma_chn->handler && (dma_chn->event & DMA_EVENT_TIMEOUT)) {
+                    dma_chn->handler(dma_chn->id, DMA_EVENT_TIMEOUT);
+                }
+            }
+            reqto &= ~(1 << (chn_id + PDMA_INTSTS_REQTOFn_Pos));
+        }
+    }
+}