ftwdt010_wdt: support faraday ftwdt010 watchdog

Faraday ftwdt010 watchdog is an architecture independant
watchdog. It is usually used in SoC chip design.
Signed-off-by: NMacpaul Lin <macpaul@andestech.com>
Signed-off-by: NWolfgang Denk <wd@denx.de>

drivers/watchdog/Makefile

@@ -26,6 +26,7 @@ include $(TOPDIR)/config.mk
 LIB	:= $(obj)libwatchdog.o
 
 COBJS-$(CONFIG_AT91SAM9_WATCHDOG) += at91sam9_wdt.o
+COBJS-$(CONFIG_FTWDT010_WATCHDOG) += ftwdt010_wdt.o
 
 COBJS	:= $(COBJS-y)
 SRCS	:= $(COBJS:.o=.c)

drivers/watchdog/ftwdt010_wdt.c

+/*
+ * Watchdog driver for the FTWDT010 Watch Dog Driver
+ *
+ * (c) Copyright 2004 Faraday Technology Corp. (www.faraday-tech.com)
+ * Based on sa1100_wdt.c by Oleg Drokin <green@crimea.edu>
+ * Based on SoftDog driver by Alan Cox <alan@redhat.com>
+ *
+ * Copyright (C) 2011 Andes Technology Corporation
+ * Macpaul Lin, Andes Technology Corporation <macpaul@andestech.com>
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * 27/11/2004 Initial release, Faraday.
+ * 12/01/2011 Port to u-boot, Macpaul Lin.
+ */
+
+#include <common.h>
+#include <watchdog.h>
+#include <asm/io.h>
+#include "ftwdt010_wdt.h"
+
+/*
+ * Set the watchdog time interval.
+ * Counter is 32 bit.
+ */
+static int ftwdt010_wdt_settimeout(unsigned int timeout)
+{
+	unsigned int reg;
+
+	struct ftwdt010_wdt *wd = (struct ftwdt010_wdt *)CONFIG_FTWDT010_BASE;
+
+	debug("Activating WDT..\n");
+
+	/* Check if disabled */
+	if (readl(&wd->wdcr) & ~FTWDT010_WDCR_ENABLE) {
+		printf("sorry, watchdog is disabled\n");
+		return -1;
+	}
+
+	/*
+	 * In a 66MHz system,
+	 * if you set WDLOAD as 0x03EF1480 (66000000)
+	 * the reset timer is 1 second.
+	 */
+	reg = FTWDT010_WDLOAD(timeout * FTWDT010_TIMEOUT_FACTOR);
+
+	writel(reg, &wd->wdload);
+
+	return 0;
+}
+
+void ftwdt010_wdt_reset()
+{
+	struct ftwdt010_wdt *wd = (struct ftwdt010_wdt *)CONFIG_FTWDT010_BASE;
+
+	/* clear control register */
+	writel(0, &wd->wdcr);
+
+	/* Write Magic number */
+	writel(FTWDT010_WDRESTART_MAGIC, &wd->wdrestart);
+
+	/* Enable WDT */
+	writel((FTWDT010_WDCR_RST | FTWDT010_WDCR_ENABLE), &wd->wdcr);
+}
+
+void ftwdt010_wdt_disable()
+{
+	struct ftwdt010_wdt *wd = (struct ftwdt010_wdt *)CONFIG_FTWDT010_BASE;
+
+	debug("Deactivating WDT..\n");
+
+	/*
+	 * It was defined with CONFIG_WATCHDOG_NOWAYOUT in Linux
+	 *
+	 * Shut off the timer.
+	 * Lock it in if it's a module and we defined ...NOWAYOUT
+	 */
+	writel(0, &wd->wdcr);
+}
+
+void hw_watchdog_reset()
+{
+	ftwdt010_wdt_reset();
+}
+
+void hw_watchdog_init(void)
+{
+	/* set timer in ms */
+	ftwdt010_wdt_settimeout(CONFIG_FTWDT010_HW_TIMEOUT * 1000);
+}

drivers/watchdog/ftwdt010_wdt.h

+/*
+ * Watchdog driver for the FTWDT010 Watch Dog Driver
+ *
+ * (c) Copyright 2004 Faraday Technology Corp. (www.faraday-tech.com)
+ * Based on sa1100_wdt.c by Oleg Drokin <green@crimea.edu>
+ * Based on SoftDog driver by Alan Cox <alan@redhat.com>
+ *
+ * Copyright (C) 2011 Andes Technology Corporation
+ * Macpaul Lin, Andes Technology Corporation <macpaul@andestech.com>
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * 27/11/2004 Initial release, Faraday.
+ * 12/01/2011 Port to u-boot, Macpaul Lin.
+ */
+
+#ifndef __FTWDT010_H
+#define __FTWDT010_H
+
+struct ftwdt010_wdt {
+	unsigned int	wdcounter;	/* Counter Reg		- 0x00 */
+	unsigned int	wdload;		/* Counter Auto Reload Reg - 0x04 */
+	unsigned int	wdrestart;	/* Counter Restart Reg	- 0x08 */
+	unsigned int	wdcr;		/* Control Reg		- 0x0c */
+	unsigned int	wdstatus;	/* Status Reg		- 0x10 */
+	unsigned int	wdclear;	/* Timer Clear		- 0x14 */
+	unsigned int	wdintrlen;	/* Interrupt Length	- 0x18 */
+};
+
+/*
+ * WDLOAD - Counter Auto Reload Register
+ *   The Auto Reload Register is set to 0x03EF1480 (66Mhz) by default.
+ *   Which means in a 66MHz system, the period of Watch Dog timer reset is
+ *   one second.
+ */
+#define FTWDT010_WDLOAD(x)		((x) & 0xffffffff)
+
+/*
+ * WDRESTART - Watch Dog Timer Counter Restart Register
+ *   If writing 0x5AB9 to WDRESTART register, Watch Dog timer will
+ *   automatically reload WDLOAD to WDCOUNTER and restart counting.
+ */
+#define FTWDT010_WDRESTART_MAGIC	0x5AB9
+
+/* WDCR - Watch Dog Timer Control Register */
+#define FTWDT010_WDCR_ENABLE		(1 << 0)
+#define FTWDT010_WDCR_RST		(1 << 1)
+#define FTWDT010_WDCR_INTR		(1 << 2)
+/* FTWDT010_WDCR_EXT bit: Watch Dog Timer External Signal Enable */
+#define FTWDT010_WDCR_EXT		(1 << 3)
+/* FTWDT010_WDCR_CLOCK bit: Clock Source: 0: PCLK, 1: EXTCLK.
+ *  The clock source PCLK cannot be gated when system sleeps, even if
+ *  WDCLOCK bit is turned on.
+ *
+ *  Faraday's Watch Dog timer can be driven by an external clock. The
+ *  programmer just needs to write one to WdCR[WdClock] bit.
+ *
+ *  Note: There is a limitation between EXTCLK and PCLK:
+ *  EXTCLK cycle time / PCLK cycle time > 2.
+ *  If the system does not need an external clock,
+ *  just keep WdCR[WdClock] bit in its default value.
+ */
+#define FTWDT010_WDCR_CLOCK		(1 << 4)
+
+/*
+ * WDSTATUS - Watch Dog Timer Status Register
+ *   This bit is set when the counter reaches Zero
+ */
+#define FTWDT010_WDSTATUS(x)		((x) & 0x1)
+
+/*
+ * WDCLEAR - Watch Dog Timer Clear Register
+ *   Writing one to this register will clear WDSTATUS.
+ */
+#define FTWDT010_WDCLEAR		(1 << 0)
+
+/*
+ * WDINTRLEN - Watch Dog Timer Interrupt Length
+ *   This register controls the duration length of wd_rst, wd_intr and wd_ext.
+ *   The default value is 0xFF.
+ */
+#define FTWDT010_WDINTRLEN(x)		((x) & 0xff)
+
+/*
+ * Variable timeout should be set in ms.
+ * (CONFIG_SYS_CLK_FREQ/1000) equals 1 ms.
+ * WDLOAD = timeout * TIMEOUT_FACTOR.
+ */
+#define FTWDT010_TIMEOUT_FACTOR		(CONFIG_SYS_CLK_FREQ / 1000) /* 1 ms */
+
+#endif /* __FTWDT010_H */