CRC engine support. NOT TESTED

diff --git a/core/crc_engine.c b/core/crc_engine.c
new file mode 100644 (file)
index 0000000..7cbf534
--- /dev/null
+++ b/core/crc_engine.c
@@ -0,0 +1,68 @@
+/****************************************************************************
+ *  core/crc_engine
+ *
+ * Copyright 2015 Nathael Pajani <nathael.pajani@ed3l.fr>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *************************************************************************** */
+
+/***************************************************************************** */
+/*                CRC engine                                                   */
+/***************************************************************************** */
+
+/* CRC engine configuration and utility functions
+ * Refer to the LPC122x documentation (UM10441.pdf) for more information
+ */
+
+
+#include "lib/stdint.h"
+#include "core/crc_engine.h"
+
+
+static uint32_t crc_seed = 0;
+
+/***************************************************************************** */
+/* Configure the CRC engine. */
+void crc_config(uint8_t poly, uint32_t seed, uint8_t data_mode, uint8_t sum_mode)
+{
+       struct lpc_crc_engine* crc_ctrl = LPC_CRC_ENGINE;
+
+       crc_ctrl->mode = ((poly & 0x03) | (data_mode & 0x0C) | (sum_mode & 0x30));
+       crc_ctrl->seed = seed;
+       crc_seed = seed;
+}
+
+
+void crc_reinit(void)
+{
+       struct lpc_crc_engine* crc_ctrl = LPC_CRC_ENGINE;
+       crc_ctrl->seed = crc_seed;
+}
+
+uint32_t crc_get_sum(void)
+{
+       struct lpc_crc_engine* crc_ctrl = LPC_CRC_ENGINE;
+       return crc_ctrl->sum;
+}
+
+
+void crc_add(uint32_t value)
+{
+       struct lpc_crc_engine* crc_ctrl = LPC_CRC_ENGINE;
+       crc_ctrl->sum = value;
+}
+
+
+

diff --git a/include/core/crc_engine.h b/include/core/crc_engine.h
new file mode 100644 (file)
index 0000000..d201a3b
--- /dev/null
+++ b/include/core/crc_engine.h
@@ -0,0 +1,81 @@
+/****************************************************************************
+ *  core/crc_engine.h
+ *
+ * Copyright 2015 Nathael Pajani <nathael.pajani@ed3l.fr>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *************************************************************************** */
+
+
+#ifndef CORE_CRC_ENGINE_H
+#define CORE_CRC_ENGINE_H
+
+/***************************************************************************** */
+/*                CRC engine                                                   */
+/***************************************************************************** */
+
+/* CRC engine configuration and utility functions
+ * Refer to the LPC122x documentation (UM10441.pdf) for more information
+ */
+
+
+#include "lib/stdint.h"
+#include "core/lpc_regs.h"
+
+
+
+/***************************************************************************** */
+/* Configure the CRC engine. */
+void crc_config(uint8_t poly, uint32_t seed, uint8_t data_mode, uint8_t sum_mode);
+
+
+void crc_reinit(void);
+
+uint32_t crc_get_sum(void);
+
+void crc_add(uint32_t value);
+
+
+
+
+/***************************************************************************** */
+/*                  CRC engine                                                 */
+/***************************************************************************** */
+/* CRC engine */
+struct lpc_crc_engine
+{
+       volatile uint32_t mode; /* 0x000 CRC Mode (R/W) */
+       volatile uint32_t seed; /* 0x004 CRC Seed (R/W) */
+       union {
+               volatile uint32_t sum;  /* 0x008 CRC CRC Checksum (R/-) */
+               volatile uint32_t data; /* 0x008 CRC Data (-/W) */
+       };
+};
+#define LPC_CRC_ENGINE  ((struct lpc_crc_engine*)LPC_CRC_BASE)
+
+/* Mode register */
+#define LPC_CRC_POLY_CRC32   (0x02)
+#define LPC_CRC_POLY_CRC16   (0x01)
+#define LPC_CRC_POLY_CRCCITT (0x00)
+#define LPC_CRC_REVERSE_DATA_BIT_ORDER (0x01 << 2)
+#define LPC_CRC_DATA_COMPLEMENT        (0x01 << 3)
+#define LPC_CRC_REVERSE_SUM_BIT_ORDER  (0x01 << 4)
+#define LPC_CRC_SUM_COMPLEMENT         (0x01 << 5)
+
+
+
+#endif  /* CORE_CRC_ENGINE_H */
+
+