+// SPDX-License-Identifier: GPL-2.0+
/*
* [origin: Linux kernel drivers/watchdog/at91sam9_wdt.c]
*
- * Watchdog driver for Atmel AT91SAM9x processors.
+ * Watchdog driver for AT91SAM9x processors.
*
* Copyright (C) 2008 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
* Copyright (C) 2008 Renaud CERRATO r.cerrato@til-technologies.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.
*/
/*
* write to this register. Inform Linux to it too
*/
-#include <common.h>
-#include <watchdog.h>
-#include <asm/arch/hardware.h>
-#include <asm/arch/io.h>
+#include <asm/io.h>
#include <asm/arch/at91_wdt.h>
+#include <common.h>
+#include <div64.h>
+#include <dm.h>
+#include <errno.h>
+#include <wdt.h>
+
+DECLARE_GLOBAL_DATA_PTR;
/*
* AT91SAM9 watchdog runs a 12bit counter @ 256Hz,
* use this to convert a watchdog
- * value from/to milliseconds.
+ * value from seconds.
*/
-#define ms_to_ticks(t) (((t << 8) / 1000) - 1)
-#define ticks_to_ms(t) (((t + 1) * 1000) >> 8)
-
-/* Hardware timeout in seconds */
-#define WDT_HW_TIMEOUT 2
+#define WDT_SEC2TICKS(s) (((s) << 8) - 1)
/*
* Set the watchdog time interval in 1/256Hz (write-once)
* Counter is 12 bit.
*/
-static int at91_wdt_settimeout(unsigned int timeout)
+static int at91_wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags)
{
- unsigned int reg;
- unsigned int mr;
+ struct at91_wdt_priv *priv = dev_get_priv(dev);
+ u64 timeout;
+ u32 ticks;
+
+ /* Calculate timeout in seconds and the resulting ticks */
+ timeout = timeout_ms;
+ do_div(timeout, 1000);
+ timeout = min_t(u64, timeout, WDT_MAX_TIMEOUT);
+ ticks = WDT_SEC2TICKS(timeout);
/* Check if disabled */
- mr = at91_sys_read(AT91_WDT_MR);
- if (mr & AT91_WDT_WDDIS) {
+ if (readl(priv->regs + AT91_WDT_MR) & AT91_WDT_MR_WDDIS) {
printf("sorry, watchdog is disabled\n");
return -1;
}
* Since WDV is a 12-bit counter, the maximum period is
* 4096 / 256 = 16 seconds.
*/
- reg = AT91_WDT_WDRSTEN /* causes watchdog reset */
- /* | AT91_WDT_WDRPROC causes processor reset only */
- | AT91_WDT_WDDBGHLT /* disabled in debug mode */
- | AT91_WDT_WDD /* restart at any time */
- | (timeout & AT91_WDT_WDV); /* timer value */
- at91_sys_write(AT91_WDT_MR, reg);
+ priv->regval = AT91_WDT_MR_WDRSTEN /* causes watchdog reset */
+ | AT91_WDT_MR_WDDBGHLT /* disabled in debug mode */
+ | AT91_WDT_MR_WDD(0xfff) /* restart at any time */
+ | AT91_WDT_MR_WDV(ticks); /* timer value */
+ writel(priv->regval, priv->regs + AT91_WDT_MR);
+
+ return 0;
+}
+
+static int at91_wdt_stop(struct udevice *dev)
+{
+ struct at91_wdt_priv *priv = dev_get_priv(dev);
+
+ /* Disable Watchdog Timer */
+ priv->regval |= AT91_WDT_MR_WDDIS;
+ writel(priv->regval, priv->regs + AT91_WDT_MR);
return 0;
}
-void hw_watchdog_reset(void)
+static int at91_wdt_reset(struct udevice *dev)
{
- at91_sys_write(AT91_WDT_CR, AT91_WDT_KEY | AT91_WDT_WDRSTT);
+ struct at91_wdt_priv *priv = dev_get_priv(dev);
+
+ writel(AT91_WDT_CR_WDRSTT | AT91_WDT_CR_KEY, priv->regs + AT91_WDT_CR);
+
+ return 0;
}
-void hw_watchdog_init(void)
+static const struct wdt_ops at91_wdt_ops = {
+ .start = at91_wdt_start,
+ .stop = at91_wdt_stop,
+ .reset = at91_wdt_reset,
+};
+
+static const struct udevice_id at91_wdt_ids[] = {
+ { .compatible = "atmel,at91sam9260-wdt" },
+ {}
+};
+
+static int at91_wdt_probe(struct udevice *dev)
{
- /* 16 seconds timer, resets enabled */
- at91_wdt_settimeout(ms_to_ticks(WDT_HW_TIMEOUT * 1000));
+ struct at91_wdt_priv *priv = dev_get_priv(dev);
+
+ priv->regs = dev_remap_addr(dev);
+ if (!priv->regs)
+ return -EINVAL;
+
+ debug("%s: Probing wdt%u\n", __func__, dev->seq);
+
+ return 0;
}
+
+U_BOOT_DRIVER(at91_wdt) = {
+ .name = "at91_wdt",
+ .id = UCLASS_WDT,
+ .of_match = at91_wdt_ids,
+ .priv_auto_alloc_size = sizeof(struct at91_wdt_priv),
+ .ops = &at91_wdt_ops,
+ .probe = at91_wdt_probe,
+};