summaryrefslogtreecommitdiffstats
path: root/drivers/watchdog
diff options
context:
space:
mode:
authorAntony Pavlov <antonynpavlov@gmail.com>2014-07-31 19:11:31 +0400
committerSascha Hauer <s.hauer@pengutronix.de>2014-08-01 07:35:51 +0200
commitb549a26fc3088b85602caf412bebd16f9e3e8ae9 (patch)
treea666349865908ca96ec3665266155f759f53a7dc /drivers/watchdog
parent03a2269509e5107f88c04c6bdde4ec692ba97a9a (diff)
downloadbarebox-b549a26fc3088b85602caf412bebd16f9e3e8ae9.tar.gz
watchdog: add minimal jz4740 driver
Also move reset_cpu() for jz4755 SoC from platform code into the new driver code. At the moment mach-xburst lacks clk support so jz4740 watchdog driver looks like a template. We can improve jz4740 watchdog driver later after adding clk support. Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Diffstat (limited to 'drivers/watchdog')
-rw-r--r--drivers/watchdog/Kconfig7
-rw-r--r--drivers/watchdog/Makefile1
-rw-r--r--drivers/watchdog/jz4740.c102
3 files changed, 110 insertions, 0 deletions
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 2e2900c..7f7b02e 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -21,4 +21,11 @@ config WATCHDOG_IMX
depends on ARCH_IMX
help
Add support for watchdog found on Freescale i.MX SoCs.
+
+config WATCHDOG_JZ4740
+ bool "Ingenic jz4740 SoC hardware watchdog"
+ depends on MACH_MIPS_XBURST
+ help
+ Hardware driver for the built-in watchdog timer on Ingenic jz4740 SoCs.
+
endif
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index f522b88..865fc47 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -1,3 +1,4 @@
obj-$(CONFIG_WATCHDOG) += wd_core.o
obj-$(CONFIG_WATCHDOG_MXS28) += im28wd.o
+obj-$(CONFIG_WATCHDOG_JZ4740) += jz4740.o
obj-$(CONFIG_WATCHDOG_IMX_RESET_SOURCE) += imxwd.o
diff --git a/drivers/watchdog/jz4740.c b/drivers/watchdog/jz4740.c
new file mode 100644
index 0000000..8ac51e0
--- /dev/null
+++ b/drivers/watchdog/jz4740.c
@@ -0,0 +1,102 @@
+/*
+ * JZ4740 Watchdog driver
+ *
+ * Copyright (C) 2014 Antony Pavlov <antonynpavlov@gmail.com>
+ *
+ * Based on jz4740_wdt.c from linux-3.15.
+ *
+ * Copyright (C) 2010, Paul Cercueil <paul@crapouillou.net>
+ *
+ * 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.
+ *
+ */
+
+#include <common.h>
+#include <init.h>
+#include <io.h>
+
+#define JZ_REG_WDT_TIMER_DATA 0x0
+#define JZ_REG_WDT_COUNTER_ENABLE 0x4
+#define JZ_REG_WDT_TIMER_COUNTER 0x8
+#define JZ_REG_WDT_TIMER_CONTROL 0xC
+
+#define JZ_WDT_CLOCK_PCLK 0x1
+#define JZ_WDT_CLOCK_RTC 0x2
+#define JZ_WDT_CLOCK_EXT 0x4
+
+#define JZ_WDT_CLOCK_DIV_SHIFT 3
+
+#define JZ_WDT_CLOCK_DIV_1 (0 << JZ_WDT_CLOCK_DIV_SHIFT)
+#define JZ_WDT_CLOCK_DIV_4 (1 << JZ_WDT_CLOCK_DIV_SHIFT)
+#define JZ_WDT_CLOCK_DIV_16 (2 << JZ_WDT_CLOCK_DIV_SHIFT)
+#define JZ_WDT_CLOCK_DIV_64 (3 << JZ_WDT_CLOCK_DIV_SHIFT)
+#define JZ_WDT_CLOCK_DIV_256 (4 << JZ_WDT_CLOCK_DIV_SHIFT)
+#define JZ_WDT_CLOCK_DIV_1024 (5 << JZ_WDT_CLOCK_DIV_SHIFT)
+
+#define JZ_EXTAL 24000000
+
+struct jz4740_wdt_drvdata {
+ void __iomem *base;
+};
+
+static struct jz4740_wdt_drvdata *reset_wd;
+
+void __noreturn reset_cpu(unsigned long addr)
+{
+ if (reset_wd) {
+ void __iomem *base = reset_wd->base;
+
+ writew(JZ_WDT_CLOCK_DIV_4 | JZ_WDT_CLOCK_EXT,
+ base + JZ_REG_WDT_TIMER_CONTROL);
+ writew(0, base + JZ_REG_WDT_TIMER_COUNTER);
+
+ /* reset after 4ms */
+ writew(JZ_EXTAL / 1000, base + JZ_REG_WDT_TIMER_DATA);
+
+ /* start wdt */
+ writeb(0x1, base + JZ_REG_WDT_COUNTER_ENABLE);
+
+ mdelay(1000);
+ } else
+ pr_err("%s: can't reset cpu\n", __func__);
+
+ hang();
+}
+EXPORT_SYMBOL(reset_cpu);
+
+static int jz4740_wdt_probe(struct device_d *dev)
+{
+ struct jz4740_wdt_drvdata *priv;
+
+ priv = xzalloc(sizeof(struct jz4740_wdt_drvdata));
+ priv->base = dev_request_mem_region(dev, 0);
+ if (!priv->base) {
+ dev_err(dev, "could not get memory region\n");
+ return -ENODEV;
+ }
+
+ if (!reset_wd)
+ reset_wd = priv;
+
+ dev->priv = priv;
+
+ return 0;
+}
+
+static __maybe_unused struct of_device_id jz4740_wdt_dt_ids[] = {
+ {
+ .compatible = "ingenic,jz4740-wdt",
+ }, {
+ /* sentinel */
+ }
+};
+
+static struct driver_d jz4740_wdt_driver = {
+ .name = "jz4740-wdt",
+ .probe = jz4740_wdt_probe,
+ .of_compatible = DRV_OF_COMPAT(jz4740_wdt_dt_ids),
+};
+device_platform_driver(jz4740_wdt_driver);