Merge pull request #28 from dominicgs/reset

LPC43xx: add watchdog reset
mossmann · Jan 27, 2017 · c9f40aa · c9f40aa
2 parents e180b2a + d3d6f3e
commit c9f40aa
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Showing 3 changed files with 37 additions and 1 deletion.
diff --git a/include/libopencm3/lpc43xx/wwdt.h b/include/libopencm3/lpc43xx/wwdt.h
@@ -48,12 +48,18 @@ extern "C" {
 
 /* Watchdog mode register */
 #define WWDT_MOD                        MMIO32(WWDT_BASE + 0x000)
+#define WWDT_MOD_WDEN      (1<<0)
+#define WWDT_MOD_WDRESET   (1<<1)
+#define WWDT_MOD_WDTOF     (1<<2)
+#define WWDT_MOD_WDINT     (1<<3)
+#define WWDT_MOD_WDPROTECT (1<<4)
 
 /* Watchdog timer constant register */
 #define WWDT_TC                         MMIO32(WWDT_BASE + 0x004)
 
 /* Watchdog feed sequence register */
 #define WWDT_FEED                       MMIO32(WWDT_BASE + 0x008)
+#define WWDT_FEED_SEQUENCE WWDT_FEED = 0xAA; WWDT_FEED = 0x55
 
 /* Watchdog timer value register */
 #define WWDT_TV                         MMIO32(WWDT_BASE + 0x00C)
@@ -66,6 +72,9 @@ extern "C" {
 
 /**@}*/
 
+/* Reset LPC4330 in timeout*4 clock cycles (min 256, max 2^24) */
+void wwdt_reset(uint32_t timeout);
+
 #ifdef __cplusplus
 }
 #endif

diff --git a/lib/lpc43xx/m4/Makefile b/lib/lpc43xx/m4/Makefile
@@ -39,7 +39,7 @@ CFLAGS		= -O2 -g3 \
 ARFLAGS		= rcs
 
 # LPC43xx common files for M4 / M0
-OBJ_LPC43XX     = gpio.o scu.o i2c.o ssp.o uart.o timer.o
+OBJ_LPC43XX     = gpio.o scu.o i2c.o ssp.o uart.o timer.o wwdt.o
 
 #LPC43xx M4 specific file + Generic LPC43xx M4/M0 files
 OBJS		= $(OBJ_LPC43XX) ipc.o

diff --git a/lib/lpc43xx/wwdt.c b/lib/lpc43xx/wwdt.c
@@ -0,0 +1,27 @@
+/*
+* This file is part of the libopencm3 project.
+*
+* Copyright (C) 2016 Dominic Spill <dominicgs@gmail.com>
+*
+* This library is free software: you can redistribute it and/or modify
+* it under the terms of the GNU Lesser General Public License as published by
+* the Free Software Foundation, either version 3 of the License, or
+* (at your option) any later version.
+*
+* This library 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 Lesser General Public License for more details.
+*
+* You should have received a copy of the GNU Lesser General Public License
+* along with this library.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <libopencm3/lpc43xx/wwdt.h>
+
+void wwdt_reset(uint32_t timeout) {
+    WWDT_MOD = WWDT_MOD_WDEN | WWDT_MOD_WDRESET;
+    timeout &= 0xFFFFFF;
+    WWDT_TC = timeout;
+    WWDT_FEED_SEQUENCE;
+}