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Revision:
171:3a7713b1edbc
Parent:
111:4336505e4b1c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TARGET_SAMR21G18A/TOOLCHAIN_GCC_ARM/dma_crc.h	Thu Nov 08 11:45:42 2018 +0000
@@ -0,0 +1,230 @@
+/**
+ * \file
+ *
+ * \brief SAM DMA cyclic redundancy check (CRC) Driver
+ *
+ * Copyright (C) 2014-2015 Atmel Corporation. All rights reserved.
+ *
+ * \asf_license_start
+ *
+ * \page License
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * 3. The name of Atmel may not be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * 4. This software may only be redistributed and used in connection with an
+ *    Atmel microcontroller product.
+ *
+ * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
+ * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ * \asf_license_stop
+ *
+ */
+/*
+ * Support and FAQ: visit <a href="http://www.atmel.com/design-support/">Atmel Support</a>
+ */
+#ifndef DMA_CRC_H_INCLUDED
+#define DMA_CRC_H_INCLUDED
+
+#include <compiler.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** DMA channel n offset. */
+#define DMA_CRC_CHANNEL_N_OFFSET 0x20
+
+/** CRC Polynomial Type. */
+enum crc_polynomial_type {
+    /** CRC16 (CRC-CCITT). */
+    CRC_TYPE_16,
+    /** CRC32 (IEEE 802.3). */
+    CRC_TYPE_32,
+};
+
+/** CRC Beat Type. */
+enum crc_beat_size {
+    /** Byte bus access. */
+    CRC_BEAT_SIZE_BYTE,
+    /** Half-word bus access. */
+    CRC_BEAT_SIZE_HWORD,
+    /** Word bus access. */
+    CRC_BEAT_SIZE_WORD,
+};
+
+/** Configurations for CRC calculation. */
+struct dma_crc_config {
+    /** CRC polynomial type. */
+    enum crc_polynomial_type type;
+    /** CRC beat size. */
+    enum crc_beat_size size;
+};
+
+/**
+ * \brief Get DMA CRC default configurations.
+ *
+ * The default configuration is as follows:
+ *  \li Polynomial type is set to CRC-16(CRC-CCITT)
+ *  \li CRC Beat size: BYTE
+ *
+ * \param[in] config default configurations
+ */
+static inline void dma_crc_get_config_defaults(struct dma_crc_config *config)
+{
+    Assert(config);
+
+    config->type = CRC_TYPE_16;
+    config->size = CRC_BEAT_SIZE_BYTE;
+}
+
+/**
+ * \brief Enable DMA CRC module with an DMA channel.
+ *
+ * This function enables a CRC calculation with an allocated DMA channel. This channel ID
+ * can be gotten from a successful \ref dma_allocate.
+ *
+ * \param[in] channel_id DMA channel expected with CRC calculation
+ * \param[in] config CRC calculation configurations
+ *
+ * \return Status of the DMC CRC.
+ * \retval STATUS_OK Get the DMA CRC module
+ * \retval STATUS_BUSY DMA CRC module is already taken and not ready yet
+ */
+static inline enum status_code dma_crc_channel_enable(uint32_t channel_id,
+        struct dma_crc_config *config)
+{
+    if (DMAC->CRCSTATUS.reg & DMAC_CRCSTATUS_CRCBUSY) {
+        return STATUS_BUSY;
+    }
+
+    DMAC->CRCCTRL.reg = DMAC_CRCCTRL_CRCBEATSIZE(config->size) |
+                        DMAC_CRCCTRL_CRCPOLY(config->type) |
+                        DMAC_CRCCTRL_CRCSRC(channel_id+DMA_CRC_CHANNEL_N_OFFSET);
+
+    DMAC->CTRL.reg |= DMAC_CTRL_CRCENABLE;
+
+    return STATUS_OK;
+}
+
+/**
+ * \brief Disable DMA CRC module.
+ *
+ */
+static inline void dma_crc_disable(void)
+{
+    DMAC->CTRL.reg &= ~DMAC_CTRL_CRCENABLE;
+    DMAC->CRCCTRL.reg = 0;
+}
+
+/**
+ * \brief Get DMA CRC checksum value.
+ *
+ * \return Calculated CRC checksum.
+ */
+static inline uint32_t dma_crc_get_checksum(void)
+{
+    if (DMAC->CRCCTRL.bit.CRCSRC == DMAC_CRCCTRL_CRCSRC_IO_Val) {
+        DMAC->CRCSTATUS.reg = DMAC_CRCSTATUS_CRCBUSY;
+    }
+
+    return DMAC->CRCCHKSUM.reg;
+}
+
+/**
+ * \brief Enable DMA CRC module with I/O.
+ *
+ * This function enables a CRC calculation with I/O mode.
+ *
+ * \param[in] config CRC calculation configurations.
+ *
+ * \return Status of the DMC CRC.
+ * \retval STATUS_OK Get the DMA CRC module
+ * \retval STATUS_BUSY DMA CRC module is already taken and not ready yet
+ */
+static inline enum status_code dma_crc_io_enable(
+    struct dma_crc_config *config)
+{
+    if (DMAC->CRCSTATUS.reg & DMAC_CRCSTATUS_CRCBUSY) {
+        return STATUS_BUSY;
+    }
+
+    if (DMAC->CTRL.reg & DMAC_CTRL_CRCENABLE) {
+        return STATUS_BUSY;
+    }
+
+    DMAC->CRCCTRL.reg = DMAC_CRCCTRL_CRCBEATSIZE(config->size) |
+                        DMAC_CRCCTRL_CRCPOLY(config->type) |
+                        DMAC_CRCCTRL_CRCSRC_IO;
+
+    if (config->type == CRC_TYPE_32) {
+        DMAC->CRCCHKSUM.reg = 0xFFFFFFFF;
+    }
+
+    DMAC->CTRL.reg |= DMAC_CTRL_CRCENABLE;
+
+    return STATUS_OK;
+}
+
+/**
+ * \brief Calculate CRC with I/O.
+ *
+ * This function calculate the CRC of the input data buffer.
+ *
+ * \param[in] buffer CRC Pointer to calculation buffer
+ * \param[in] total_beat_size Total beat size to be calculated
+ *
+ * \return Calculated CRC checksum value.
+ */
+static inline void dma_crc_io_calculation(void *buffer,
+        uint32_t total_beat_size)
+{
+    uint32_t counter = total_beat_size;
+    uint8_t *buffer_8;
+    uint16_t *buffer_16;
+    uint32_t *buffer_32;
+
+    for (counter=0; counter<total_beat_size; counter++) {
+        if (DMAC->CRCCTRL.bit.CRCBEATSIZE == CRC_BEAT_SIZE_BYTE) {
+            buffer_8 = buffer;
+            DMAC->CRCDATAIN.reg = buffer_8[counter];
+        } else if (DMAC->CRCCTRL.bit.CRCBEATSIZE == CRC_BEAT_SIZE_HWORD) {
+            buffer_16 = buffer;
+            DMAC->CRCDATAIN.reg = buffer_16[counter];
+        } else if (DMAC->CRCCTRL.bit.CRCBEATSIZE == CRC_BEAT_SIZE_WORD) {
+            buffer_32 = buffer;
+            DMAC->CRCDATAIN.reg = buffer_32[counter];
+        }
+        /* Wait several cycle to make sure CRC complete */
+        nop();
+        nop();
+        nop();
+        nop();
+    }
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* DMA_CRC_H_INCLUDED */