watchdog: octeontx_wdt: Add support for start and stop
This patch enhances the Octeon TX/TX2 watchdog driver to fully enable
the WDT. With this changes, the "wdt" command is now also supported
on these platforms.
Signed-off-by: Suneel Garapati <sgarapati@marvell.com>
Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Aaron Williams <awilliams@marvell.com>
Cc: Suneel Garapati <sgarapati@marvell.com>
Cc: Chandrakala Chavva <cchavva@marvell.com>
diff --git a/drivers/watchdog/octeontx_wdt.c b/drivers/watchdog/octeontx_wdt.c
index 1e0670e..88708dc 100644
--- a/drivers/watchdog/octeontx_wdt.c
+++ b/drivers/watchdog/octeontx_wdt.c
@@ -5,25 +5,90 @@
* https://spdx.org/licenses
*/
+#include <clk.h>
#include <dm.h>
#include <errno.h>
#include <wdt.h>
#include <asm/io.h>
+#include <linux/bitfield.h>
DECLARE_GLOBAL_DATA_PTR;
+#define CORE0_WDOG_OFFSET 0x40000
#define CORE0_POKE_OFFSET 0x50000
#define CORE0_POKE_OFFSET_MASK 0xfffffULL
+#define WDOG_MODE GENMASK_ULL(1, 0)
+#define WDOG_LEN GENMASK_ULL(19, 4)
+#define WDOG_CNT GENMASK_ULL(43, 20)
+
struct octeontx_wdt {
void __iomem *reg;
+ struct clk clk;
};
+static int octeontx_wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags)
+{
+ struct octeontx_wdt *priv = dev_get_priv(dev);
+ u64 clk_rate, val;
+ u64 tout_wdog;
+
+ clk_rate = clk_get_rate(&priv->clk);
+ if (IS_ERR_VALUE(clk_rate))
+ return -EINVAL;
+
+ /* Watchdog counts in 1024 cycle steps */
+ tout_wdog = (clk_rate * timeout_ms / 1000) >> 10;
+
+ /*
+ * We can only specify the upper 16 bits of a 24 bit value.
+ * Round up
+ */
+ tout_wdog = (tout_wdog + 0xff) >> 8;
+
+ /* If the timeout overflows the hardware limit, set max */
+ if (tout_wdog >= 0x10000)
+ tout_wdog = 0xffff;
+
+ val = FIELD_PREP(WDOG_MODE, 0x3) |
+ FIELD_PREP(WDOG_LEN, tout_wdog) |
+ FIELD_PREP(WDOG_CNT, tout_wdog << 8);
+ writeq(val, priv->reg + CORE0_WDOG_OFFSET);
+
+ return 0;
+}
+
+static int octeontx_wdt_stop(struct udevice *dev)
+{
+ struct octeontx_wdt *priv = dev_get_priv(dev);
+
+ writeq(0, priv->reg + CORE0_WDOG_OFFSET);
+
+ return 0;
+}
+
+static int octeontx_wdt_expire_now(struct udevice *dev, ulong flags)
+{
+ octeontx_wdt_stop(dev);
+
+ /* Start with 100ms timeout to expire immediately */
+ octeontx_wdt_start(dev, 100, flags);
+
+ return 0;
+}
+
static int octeontx_wdt_reset(struct udevice *dev)
{
struct octeontx_wdt *priv = dev_get_priv(dev);
+ writeq(~0ULL, priv->reg + CORE0_POKE_OFFSET);
+
+ return 0;
+}
+
- writeq(~0ULL, priv->reg);
+static int octeontx_wdt_remove(struct udevice *dev)
+{
+ octeontx_wdt_stop(dev);
return 0;
}
@@ -31,24 +96,35 @@
static int octeontx_wdt_probe(struct udevice *dev)
{
struct octeontx_wdt *priv = dev_get_priv(dev);
+ int ret;
priv->reg = dev_remap_addr(dev);
if (!priv->reg)
return -EINVAL;
/*
- * Save core poke register address in reg (its not 0xa0000 as
- * extracted from the DT but 0x50000 instead)
+ * Save base register address in reg masking lower 20 bits
+ * as 0xa0000 appears when extracted from the DT
*/
priv->reg = (void __iomem *)(((u64)priv->reg &
- ~CORE0_POKE_OFFSET_MASK) |
- CORE0_POKE_OFFSET);
+ ~CORE0_POKE_OFFSET_MASK));
+
+ ret = clk_get_by_index(dev, 0, &priv->clk);
+ if (ret < 0)
+ return ret;
+
+ ret = clk_enable(&priv->clk);
+ if (ret)
+ return ret;
return 0;
}
static const struct wdt_ops octeontx_wdt_ops = {
.reset = octeontx_wdt_reset,
+ .start = octeontx_wdt_start,
+ .stop = octeontx_wdt_stop,
+ .expire_now = octeontx_wdt_expire_now,
};
static const struct udevice_id octeontx_wdt_ids[] = {
@@ -63,4 +139,6 @@
.ops = &octeontx_wdt_ops,
.priv_auto_alloc_size = sizeof(struct octeontx_wdt),
.probe = octeontx_wdt_probe,
+ .remove = octeontx_wdt_remove,
+ .flags = DM_FLAG_OS_PREPARE,
};