[U-Boot] [RFC PATCH 27/29] drivers: watchdog: add reset support for OcteonTX

[Suneel Garapati <suneelglinux@gmail.com>]

From: Suneel Garapati <sgarapati@marvell.com>

Adds support for Core 0 poke on OcteonTX and OcteonTX2
platforms.

Signed-off-by: Suneel Garapati <sgarapati@marvell.com>
---
 drivers/watchdog/Kconfig        | 10 +++++
 drivers/watchdog/Makefile       |  1 +
 drivers/watchdog/octeontx_wdt.c | 76 +++++++++++++++++++++++++++++++++
 3 files changed, 87 insertions(+)
 create mode 100644 drivers/watchdog/octeontx_wdt.c

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 8c16d69d33..61357a7f0a 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -121,6 +121,16 @@ config WDT_MTK
 	  The watchdog timer is stopped when initialized.
 	  It performs full SoC reset.
 
+config WDT_OCTEONTX
+	bool "OcteonTX core watchdog support"
+	depends on WDT && (ARCH_OCTEONTX || ARCH_OCTEONTX2)
+	default y if WDT && ARCH_OCTEONTX || ARCH_OCTEONTX2
+	imply WATCHDOG
+	help
+	  This enables OcteonTX watchdog driver, which can be
+	  found on OcteonTX/TX2 chipsets and inline with driver model.
+	  Only supports watchdog reset.
+
 config WDT_OMAP3
         bool "TI OMAP watchdog timer support"
         depends on WDT && ARCH_OMAP2PLUS
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 955caef815..66b20b0e98 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -25,6 +25,7 @@ obj-$(CONFIG_WDT_CDNS) += cdns_wdt.o
 obj-$(CONFIG_WDT_MPC8xx) += mpc8xx_wdt.o
 obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o
 obj-$(CONFIG_WDT_MTK) += mtk_wdt.o
+obj-$(CONFIG_WDT_OCTEONTX) += octeontx_wdt.o
 obj-$(CONFIG_WDT_OMAP3) += omap_wdt.o
 obj-$(CONFIG_WDT_SP805) += sp805_wdt.o
 obj-$(CONFIG_WDT_STM32MP) += stm32mp_wdt.o
diff --git a/drivers/watchdog/octeontx_wdt.c b/drivers/watchdog/octeontx_wdt.c
new file mode 100644
index 0000000000..9362ad99bf
--- /dev/null
+++ b/drivers/watchdog/octeontx_wdt.c
@@ -0,0 +1,76 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2019 Marvell International Ltd.
+ *
+ * https://spdx.org/licenses
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <wdt.h>
+#include <asm/io.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define CORE0_POKE_OFFSET 0x50000
+
+#if CONFIG_IS_ENABLED(ARCH_OCTEONTX)
+#define REG_BASE 0x844000000000
+#elif CONFIG_IS_ENABLED(ARCH_OCTEONTX2)
+#define REG_BASE 0x802000000000
+#endif
+
+struct octeontx_wdt {
+	void __iomem *reg;
+};
+
+static struct udevice *wdt_dev;
+
+static int octeontx_wdt_reset(struct udevice *dev)
+{
+	struct octeontx_wdt *priv;
+	u64 poke_reg;
+
+	if (dev) {
+		priv = dev_get_priv(dev);
+		poke_reg = ((u64)priv->reg & ~0xfffffULL) | CORE0_POKE_OFFSET;
+	} else {
+		poke_reg = REG_BASE + CORE0_POKE_OFFSET;
+	}
+	writeq(~0ULL, poke_reg);
+
+	return 0;
+}
+
+static int octeontx_wdt_probe(struct udevice *dev)
+{
+	struct octeontx_wdt *priv = dev_get_priv(dev);
+	fdt_addr_t addr;
+
+	addr = dev_read_addr_index(dev, 0);
+	if (addr == FDT_ADDR_T_NONE)
+		return -ENODEV;
+
+	priv->reg = (void __iomem *)addr;
+	wdt_dev = dev;
+
+	return 0;
+}
+
+static const struct wdt_ops octeontx_wdt_ops = {
+	.reset = octeontx_wdt_reset,
+};
+
+static const struct udevice_id octeontx_wdt_ids[] = {
+	{ .compatible = "arm,sbsa-gwdt" },
+	{}
+};
+
+U_BOOT_DRIVER(wdt_octeontx) = {
+	.name = "wdt_octeontx",
+	.id = UCLASS_WDT,
+	.of_match = octeontx_wdt_ids,
+	.ops = &octeontx_wdt_ops,
+	.priv_auto_alloc_size = sizeof(struct octeontx_wdt),
+	.probe = octeontx_wdt_probe,
+};
-- 
2.23.0