Hi Guenter,
Thanks for your comment.
> On 05/23/2017 11:34 PM, Keiji Hayashibara wrote:
> > Add a watchdog driver for Socionext UniPhier series SoC.
> > Note that the timeout value for this device must be a power
> > of 2 because of the specification.
> >
> > Signed-off-by: Keiji Hayashibara <hayashibara.ke...@socionext.com>
> > ---
> > .../devicetree/bindings/watchdog/uniphier-wdt.txt | 20 ++
> > Documentation/watchdog/watchdog-parameters.txt | 6 +
> > drivers/watchdog/Kconfig | 11 +
> > drivers/watchdog/Makefile | 1 +
> > drivers/watchdog/uniphier_wdt.c | 273
> > +++++++++++++++++++++
> > 5 files changed, 311 insertions(+)
> > create mode 100644
> > Documentation/devicetree/bindings/watchdog/uniphier-wdt.txt
> > create mode 100644 drivers/watchdog/uniphier_wdt.c
> >
> > diff --git a/Documentation/devicetree/bindings/watchdog/uniphier-wdt.txt
> b/Documentation/devicetree/bindings/watchdog/uniphier-wdt.txt
> > new file mode 100644
> > index 0000000..a59d1ba
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/watchdog/uniphier-wdt.txt
> > @@ -0,0 +1,20 @@
> > +UniPhier watchdog timer controller
> > +
> > +This UniPhier watchdog timer controller must be under sysctrl compatible
> > node.
> > +
> > +Required properties:
> > +- compatible: should be "socionext,uniphier-wdt"
> > +
> > +Example:
> > +
> > + sysctrl@61840000 {
> > + compatible = "socionext,uniphier-ld11-sysctrl",
> > + "simple-mfd", "syscon";
> > + reg = <0x61840000 0x4000>;
> > +
> > + sys_wdt: watchdog {
> > + compatible = "socionext,uniphier-wdt";
> > + }
> > +
> > + other nodes ...
> > + };
>
> Bindings should be in a separate patch.
I will do in next v2 patch.
> > diff --git a/Documentation/watchdog/watchdog-parameters.txt
> > b/Documentation/watchdog/watchdog-parameters.txt > index
> 4f7d86d..6f9d7b4 100644
> > --- a/Documentation/watchdog/watchdog-parameters.txt
> > +++ b/Documentation/watchdog/watchdog-parameters.txt
> > @@ -369,6 +369,12 @@ timeout: Watchdog timeout in seconds. (0<timeout<N,
> > default=60)
> > nowayout: Watchdog cannot be stopped once started
> > (default=kernel config parameter)
> > -------------------------------------------------
> > +uniphier_wdt:
> > +timeout: Watchdog timeout in power of two seconds.
> > + (1 <= timeout <= 128, default=64)
> > +nowayout: Watchdog cannot be stopped once started
> > + (default=kernel config parameter)
> > +-------------------------------------------------
> > w83627hf_wdt:
> > wdt_io: w83627hf/thf WDT io port (default 0x2E)
> > timeout: Watchdog timeout in seconds. 1 <= timeout <= 255, default=60.
> > diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> > index 52a70ee..2a9d9a6 100644
> > --- a/drivers/watchdog/Kconfig
> > +++ b/drivers/watchdog/Kconfig
> > @@ -744,6 +744,17 @@ config ZX2967_WATCHDOG
> > To compile this driver as a module, choose M here: the
> > module will be called zx2967_wdt.
> >
> > +config UNIPHIER_WATCHDOG
> > + tristate "UniPhier watchdog support"
> > + depends on ARCH_UNIPHIER || COMPILE_TEST
> > + select WATCHDOG_CORE
> > + help
> > + Say Y here to include support watchdog timer embedded
> > + into the UniPhier system.
> > +
> > + To compile this driver as a module, choose M here: the
> > + module will be called uniphier_wdt.
> > +
> > # AVR32 Architecture
> >
> > config AT32AP700X_WDT
> > diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> > index a2126e2..0928dac 100644
> > --- a/drivers/watchdog/Makefile
> > +++ b/drivers/watchdog/Makefile
> > @@ -84,6 +84,7 @@ obj-$(CONFIG_ATLAS7_WATCHDOG) += atlas7_wdt.o
> > obj-$(CONFIG_RENESAS_WDT) += renesas_wdt.o
> > obj-$(CONFIG_ASPEED_WATCHDOG) += aspeed_wdt.o
> > obj-$(CONFIG_ZX2967_WATCHDOG) += zx2967_wdt.o
> > +obj-$(CONFIG_UNIPHIER_WATCHDOG) += uniphier_wdt.o
> >
> > # AVR32 Architecture
> > obj-$(CONFIG_AT32AP700X_WDT) += at32ap700x_wdt.o
> > diff --git a/drivers/watchdog/uniphier_wdt.c
> > b/drivers/watchdog/uniphier_wdt.c
> > new file mode 100644
> > index 0000000..80ad2a3
> > --- /dev/null
> > +++ b/drivers/watchdog/uniphier_wdt.c
> > @@ -0,0 +1,273 @@
> > +/*
> > + * Watchdog driver for the UniPhier watchdog timer
> > + *
> > + * (c) Copyright 2014 Panasonic Corporation
> > + * (c) Copyright 2016 Socionext Inc.
> > + * All rights reserved.
> > + *
> > + * 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.
> > + */
> > +
> > +#include <linux/delay.h>
> > +#include <linux/module.h>
> > +#include <linux/mfd/syscon.h>
> > +#include <linux/of.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/regmap.h>
> > +#include <linux/watchdog.h>
> > +
> > +/* WDT timer setting register */
> > +#define WDTTIMSET 0x3004
> > +#define WDTTIMSET_PERIOD_MASK (0xf << 0)
> > +#define WDTTIMSET_PERIOD_1_SEC (0x3 << 0)
> > +#define WDTTIMSET_PERIOD_2_SEC (0x4 << 0)
> > +#define WDTTIMSET_PERIOD_4_SEC (0x5 << 0)
> > +#define WDTTIMSET_PERIOD_8_SEC (0x6 << 0)
> > +#define WDTTIMSET_PERIOD_16_SEC (0x7 << 0)
> > +#define WDTTIMSET_PERIOD_32_SEC (0x8 << 0)
> > +#define WDTTIMSET_PERIOD_64_SEC (0x9 << 0)
> > +#define WDTTIMSET_PERIOD_128_SEC (0xa << 0)
> > +
> > +/* WDT reset selection register */
> > +#define WDTRSTSEL 0x3008
> > +#define WDTRSTSEL_RSTSEL_MASK (0x3 << 0)
> > +#define WDTRSTSEL_RSTSEL_BOTH (0x0 << 0)
> > +#define WDTRSTSEL_RSTSEL_IRQ_ONLY (0x2 << 0)
> > +
> > +/* WDT control register */
> > +#define WDTCTRL 0x300c
> > +#define WDTCTRL_STATUS BIT(8)
> > +#define WDTCTRL_CLEAR BIT(1)
> > +#define WDTCTRL_ENABLE BIT(0)
> > +
>
> Should include bitops.h.
I will do in next v2 patch.
> > +#define SEC_TO_WDTTIMSET_PRD(sec) \
> > + (ilog2(sec) + WDTTIMSET_PERIOD_1_SEC)
> > +
> > +#define WDTST_TIMEOUT 1000 /* usec */
> > +
> > +#define WDT_DEFAULT_TIMEOUT 64 /* Default is 64 seconds */
> > +#define WDT_PERIOD_MIN 1
> > +#define WDT_PERIOD_MAX 128
> > +
> > +static unsigned int timeout = WDT_DEFAULT_TIMEOUT;
> > +static bool nowayout = WATCHDOG_NOWAYOUT;
> > +
> > +struct uniphier_wdt_dev {
> > + struct watchdog_device wdt_dev;
> > + struct regmap *regmap;
> > +};
> > +
> > +/*
> > + * UniPhier Watchdog operations
> > + */
> > +static int uniphier_watchdog_ping(struct watchdog_device *w)
> > +{
> > + struct uniphier_wdt_dev *wdev = watchdog_get_drvdata(w);
> > +
> > + /* Clear counter */
> > + return regmap_write(wdev->regmap, WDTCTRL,
> > + WDTCTRL_CLEAR | WDTCTRL_ENABLE);
> > +}
> > +
> > +static int __uniphier_watchdog_start(struct regmap *regmap, unsigned int
> > sec)
> > +{
> > + int ret;
> > +
> > + /* Setup period */
> > + ret = regmap_write(regmap, WDTTIMSET,
> > + SEC_TO_WDTTIMSET_PRD(sec));
> > + if (ret)
> > + return ret;
> > +
> > + /* Enable and clear watchdog */
> > + return regmap_write(regmap, WDTCTRL, WDTCTRL_ENABLE | WDTCTRL_CLEAR);
> > +}
> > +
> > +static int __uniphier_watchdog_stop(struct regmap *regmap)
> > +{
> > + /* Disable and stop watchdog */
> > + return regmap_write_bits(regmap, WDTCTRL, WDTCTRL_ENABLE, 0);
> > +}
> > +
> > +static int __uniphier_watchdog_restart(struct regmap *regmap, unsigned int
> > sec)
> > +{
> > + unsigned int val;
> > + int ret;
> > +
> > + ret = __uniphier_watchdog_stop(regmap);
> > + if (ret)
> > + return ret;
> > +
> > + ret = regmap_read_poll_timeout(regmap, WDTCTRL, val,
> > + !(val & WDTCTRL_STATUS),
> > + 0, WDTST_TIMEOUT);
> > + if (ret)
> > + return ret;
> > +
> > + return __uniphier_watchdog_start(regmap, sec);
> > +}
> > +
> > +static int uniphier_watchdog_start(struct watchdog_device *w)
> > +{
> > + struct uniphier_wdt_dev *wdev = watchdog_get_drvdata(w);
> > + unsigned int tmp_timeout;
> > +
> > + tmp_timeout = roundup_pow_of_two(w->timeout);
> > +
> > + return __uniphier_watchdog_start(wdev->regmap, tmp_timeout);
> > +}
> > +
> > +static int uniphier_watchdog_stop(struct watchdog_device *w)
> > +{
> > + struct uniphier_wdt_dev *wdev = watchdog_get_drvdata(w);
> > +
> > + return __uniphier_watchdog_stop(wdev->regmap);
> > +}
> > +
> > +static int uniphier_watchdog_set_timeout(struct watchdog_device *w,
> > + unsigned int t)
> > +{
> > + struct uniphier_wdt_dev *wdev = watchdog_get_drvdata(w);
> > + unsigned int tmp_timeout;
> > + int ret;
> > +
> > + tmp_timeout = roundup_pow_of_two(t);
> > + if (tmp_timeout == w->timeout)
> > + return 0;
> > +
> > + if (watchdog_active(w)) {
> > + ret = __uniphier_watchdog_restart(wdev->regmap, tmp_timeout);
> > + if (ret)
> > + return ret;
> > + }
> > +
> > + w->timeout = tmp_timeout;
> > +
> > + return 0;
> > +}
> > +
> > +/*
> > + * Kernel Interfaces
> > + */
> > +static const struct watchdog_info uniphier_wdt_info = {
> > + .identity = "uniphier-wdt",
> > + .options = WDIOF_SETTIMEOUT |
> > + WDIOF_KEEPALIVEPING |
> > + WDIOF_MAGICCLOSE |
> > + WDIOF_OVERHEAT,
> > +};
> > +
> > +static const struct watchdog_ops uniphier_wdt_ops = {
> > + .owner = THIS_MODULE,
> > + .start = uniphier_watchdog_start,
> > + .stop = uniphier_watchdog_stop,
> > + .ping = uniphier_watchdog_ping,
> > + .set_timeout = uniphier_watchdog_set_timeout,
> > + .restart = NULL,
>
> What is this about ? It is unnecessary to set a static variable to NULL.
I will remove ".restart" in next v2 patch.
> > +};
> > +
> > +static int uniphier_wdt_probe(struct platform_device *pdev)
> > +{
> > + struct device *dev = &pdev->dev;
> > + struct uniphier_wdt_dev *wdev;
> > + struct regmap *regmap;
> > + struct device_node *parent;
> > + int ret;
> > +
> > + wdev = devm_kzalloc(dev, sizeof(*wdev), GFP_KERNEL);
> > + if (!wdev)
> > + return -ENOMEM;
> > +
> > + platform_set_drvdata(pdev, wdev);
> > +
> > + parent = of_get_parent(dev->of_node); /* parent should be syscon node */
> > + regmap = syscon_node_to_regmap(parent);
> > + of_node_put(parent);
> > + if (IS_ERR(regmap))
> > + return PTR_ERR(regmap);
> > +
> > + wdev->regmap = regmap;
> > + wdev->wdt_dev.info = &uniphier_wdt_info;
> > + wdev->wdt_dev.ops = &uniphier_wdt_ops;
> > + wdev->wdt_dev.timeout = WDT_DEFAULT_TIMEOUT;
> > + wdev->wdt_dev.max_timeout = WDT_PERIOD_MAX;
> > + wdev->wdt_dev.min_timeout = WDT_PERIOD_MIN;
> > + wdev->wdt_dev.parent = dev;
> > +
> > + watchdog_init_timeout(&wdev->wdt_dev, timeout, dev);
> > + watchdog_set_nowayout(&wdev->wdt_dev, nowayout);
> > + watchdog_set_restart_priority(&wdev->wdt_dev, 128);
>
> This does not make sense without a restart handler function.
I will remove it in next v2 patch.
> > +
> > + watchdog_set_drvdata(&wdev->wdt_dev, wdev);
> > +
> > + uniphier_watchdog_stop(&wdev->wdt_dev);
> > + ret = regmap_write(wdev->regmap, WDTRSTSEL, WDTRSTSEL_RSTSEL_BOTH);
> > + if (ret)
> > + return ret;
> > +
> > + ret = watchdog_register_device(&wdev->wdt_dev);
>
> You can use devm_watchdog_register_device().
I will use it in next v2 patch.
> > + if (ret)
> > + return ret;
> > +
> > + dev_info(dev, "watchdog driver (timeout=%d sec, nowayout=%d)\n",
> > + wdev->wdt_dev.timeout, nowayout);
> > +
> > + return 0;
> > +}
> > +
> > +static void uniphier_wdt_shutdown(struct platform_device *pdev)
> > +{
> > + struct uniphier_wdt_dev *wdev = platform_get_drvdata(pdev);
> > +
> > + if (watchdog_active(&wdev->wdt_dev))
> > + uniphier_watchdog_stop(&wdev->wdt_dev);
>
> Can you use WDOG_STOP_ON_REBOOT instead ?
Yes, I will remove uniphier_wdt_shutdown() and call watchdog_stop_on_reboot()
in uniphier_wdt_probe().
> > +}
> > +
> > +static int uniphier_wdt_remove(struct platform_device *pdev)
> > +{
> > + struct uniphier_wdt_dev *wdev = platform_get_drvdata(pdev);
> > +
> > + watchdog_unregister_device(&wdev->wdt_dev);
> > +
> > + return 0;
> > +}
> > +
> > +static const struct of_device_id uniphier_wdt_dt_ids[] = {
> > + { .compatible = "socionext,uniphier-wdt" },
> > + { /* sentinel */ }
> > +};
> > +MODULE_DEVICE_TABLE(of, uniphier_wdt_dt_ids);
> > +
> > +static struct platform_driver uniphier_wdt_driver = {
> > + .probe = uniphier_wdt_probe,
> > + .remove = uniphier_wdt_remove,
> > + .shutdown = uniphier_wdt_shutdown,
> > + .driver = {
> > + .name = "uniphier-wdt",
> > + .of_match_table = uniphier_wdt_dt_ids,
> > + },
> > +};
> > +
> > +module_platform_driver(uniphier_wdt_driver);
> > +
> > +module_param(timeout, uint, 0000);
> > +MODULE_PARM_DESC(timeout,
> > + "Watchdog timeout seconds in power of 2. (0 < timeout < 128, default="
> > + __MODULE_STRING(WDT_DEFAULT_TIMEOUT) ")");
> > +
> > +module_param(nowayout, bool, 0000);
> > +MODULE_PARM_DESC(nowayout,
> > + "Watchdog cannot be stopped once started (default="
> > + __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
> > +
> > +MODULE_AUTHOR("Socionext Inc.");
> > +MODULE_DESCRIPTION("UniPhier Watchdog Device Driver");
> > +MODULE_LICENSE("GPL v2");
> >
-----
Best Regards,
Keiji Hayashibara
