watchdog: Add support for Xilinx Microblaze watchdog

Watchdog can be used on Microblaze, PPC and Zynq hw designs.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Tom Rini <trini@ti.com>

2 files changed, 88 insertions, 0 deletions

diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index b1f4e0f..13e7c37 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -32,6 +32,7 @@ COBJS-y += imx_watchdog.o
 endif
 COBJS-$(CONFIG_TNETV107X_WATCHDOG) += tnetv107x_wdt.o
 COBJS-$(CONFIG_S5P)               += s5p_wdt.o
+COBJS-$(CONFIG_XILINX_TB_WATCHDOG) += xilinx_tb_wdt.o
 
 COBJS	:= $(COBJS-y)
 SRCS	:= $(COBJS:.o=.c)
diff --git a/drivers/watchdog/xilinx_tb_wdt.c b/drivers/watchdog/xilinx_tb_wdt.c
new file mode 100644
index 0000000..f7c722e
--- /dev/null
+++ b/drivers/watchdog/xilinx_tb_wdt.c
@@ -0,0 +1,87 @@
+/*
+ * Copyright (c) 2011-2013 Xilinx Inc.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/microblaze_intc.h>
+#include <asm/processor.h>
+#include <watchdog.h>
+
+#define XWT_CSR0_WRS_MASK	0x00000008 /* Reset status Mask */
+#define XWT_CSR0_WDS_MASK	0x00000004 /* Timer state Mask */
+#define XWT_CSR0_EWDT1_MASK	0x00000002 /* Enable bit 1 Mask*/
+#define XWT_CSRX_EWDT2_MASK	0x00000001 /* Enable bit 2 Mask */
+
+struct watchdog_regs {
+	u32 twcsr0; /* 0x0 */
+	u32 twcsr1; /* 0x4 */
+	u32 tbr; /* 0x8 */
+};
+
+static struct watchdog_regs *watchdog_base =
+			(struct watchdog_regs *)CONFIG_WATCHDOG_BASEADDR;
+
+void hw_watchdog_reset(void)
+{
+	u32 reg;
+
+	/* Read the current contents of TCSR0 */
+	reg = readl(&watchdog_base->twcsr0);
+
+	/* Clear the watchdog WDS bit */
+	if (reg & (XWT_CSR0_EWDT1_MASK | XWT_CSRX_EWDT2_MASK))
+		writel(reg | XWT_CSR0_WDS_MASK, &watchdog_base->twcsr0);
+}
+
+void hw_watchdog_disable(void)
+{
+	u32 reg;
+
+	/* Read the current contents of TCSR0 */
+	reg = readl(&watchdog_base->twcsr0);
+
+	writel(reg & ~XWT_CSR0_EWDT1_MASK, &watchdog_base->twcsr0);
+	writel(~XWT_CSRX_EWDT2_MASK, &watchdog_base->twcsr1);
+
+	puts("Watchdog disabled!\n");
+}
+
+static void hw_watchdog_isr(void *arg)
+{
+	hw_watchdog_reset();
+}
+
+int hw_watchdog_init(void)
+{
+	int ret;
+
+	writel((XWT_CSR0_WRS_MASK | XWT_CSR0_WDS_MASK | XWT_CSR0_EWDT1_MASK),
+	       &watchdog_base->twcsr0);
+	writel(XWT_CSRX_EWDT2_MASK, &watchdog_base->twcsr1);
+
+	ret = install_interrupt_handler(CONFIG_WATCHDOG_IRQ,
+						hw_watchdog_isr, NULL);
+	if (ret)
+		return 1;
+
+	return 0;
+}