Add watchdog timer specific driver for Loongson1 SoC. Signed-off-by: Yang Ling <gnaygnil@xxxxxxxxx> --- drivers/watchdog/Kconfig | 7 ++ drivers/watchdog/Makefile | 1 + drivers/watchdog/loongson1_wdt.c | 158 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 166 insertions(+) create mode 100644 drivers/watchdog/loongson1_wdt.c diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 50dbaa8..28c44f2 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -1553,6 +1553,13 @@ config PIC32_DMT To compile this driver as a loadable module, choose M here. The module will be called pic32-dmt. +config LOONGSON1_WDT + tristate "Loongson1 SoC hardware watchdog" + depends on MACH_LOONGSON32 + select WATCHDOG_CORE + help + Hardware driver for the Loongson1 SoC Watchdog Timer. + # PARISC Architecture # POWERPC Architecture diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index cba0043..bd3b00e 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -162,6 +162,7 @@ obj-$(CONFIG_IMGPDC_WDT) += imgpdc_wdt.o obj-$(CONFIG_MT7621_WDT) += mt7621_wdt.o obj-$(CONFIG_PIC32_WDT) += pic32-wdt.o obj-$(CONFIG_PIC32_DMT) += pic32-dmt.o +obj-$(CONFIG_LOONGSON1_WDT) += loongson1_wdt.o # PARISC Architecture diff --git a/drivers/watchdog/loongson1_wdt.c b/drivers/watchdog/loongson1_wdt.c new file mode 100644 index 0000000..fe96e2c --- /dev/null +++ b/drivers/watchdog/loongson1_wdt.c @@ -0,0 +1,158 @@ +/* + * Copyright (c) 2016 Yang Ling <gnaygnil@xxxxxxxxx> + * + * 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 <linux/module.h> +#include <linux/watchdog.h> +#include <linux/platform_device.h> +#include <linux/clk.h> + +#include <loongson1.h> + +#define MIN_HEARTBEAT 1 +#define MAX_HEARTBEAT 30 +#define DEFAULT_HEARTBEAT 10 + +static bool nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, bool, 0); + +static unsigned int heartbeat = DEFAULT_HEARTBEAT; +module_param(heartbeat, uint, 0); + +struct ls1x_wdt_drvdata { + struct watchdog_device wdt; + void __iomem *base; + unsigned int count; + struct clk *clk; +}; + +static int ls1x_wdt_ping(struct watchdog_device *wdt_dev) +{ + struct ls1x_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev); + + writel(0x1, drvdata->base + WDT_EN); + writel(drvdata->count, drvdata->base + WDT_TIMER); + writel(0x1, drvdata->base + WDT_SET); + + return 0; +} + +static int ls1x_wdt_set_timeout(struct watchdog_device *wdt_dev, + unsigned int new_timeout) +{ + struct ls1x_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev); + int counts_per_second; + + if (watchdog_init_timeout(wdt_dev, new_timeout, NULL)) + return -EINVAL; + + counts_per_second = clk_get_rate(drvdata->clk); + drvdata->count = counts_per_second * wdt_dev->timeout; + + ls1x_wdt_ping(wdt_dev); + + return 0; +} + +static int ls1x_wdt_start(struct watchdog_device *wdt_dev) +{ + ls1x_wdt_set_timeout(wdt_dev, wdt_dev->timeout); + + return 0; +} + +static int ls1x_wdt_stop(struct watchdog_device *wdt_dev) +{ + struct ls1x_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev); + + writel(0x0, drvdata->base + WDT_EN); + + return 0; +} + +static const struct watchdog_info ls1x_wdt_info = { + .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, + .identity = "Loongson1 Watchdog", +}; + +static const struct watchdog_ops ls1x_wdt_ops = { + .owner = THIS_MODULE, + .start = ls1x_wdt_start, + .stop = ls1x_wdt_stop, + .ping = ls1x_wdt_ping, + .set_timeout = ls1x_wdt_set_timeout, +}; + +static int ls1x_wdt_probe(struct platform_device *pdev) +{ + struct ls1x_wdt_drvdata *drvdata; + struct watchdog_device *ls1x_wdt; + struct resource *res; + int ret; + + drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL); + if (!drvdata) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + drvdata->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(drvdata->base)) + return PTR_ERR(drvdata->base); + + drvdata->clk = devm_clk_get(&pdev->dev, pdev->name); + if (IS_ERR(drvdata->clk)) { + dev_err(&pdev->dev, "failed to get %s clock\n", pdev->name); + return PTR_ERR(drvdata->clk); + } + clk_prepare_enable(drvdata->clk); + + ls1x_wdt = &drvdata->wdt; + ls1x_wdt->info = &ls1x_wdt_info; + ls1x_wdt->ops = &ls1x_wdt_ops; + ls1x_wdt->timeout = heartbeat; + ls1x_wdt->min_timeout = MIN_HEARTBEAT; + ls1x_wdt->max_timeout = MAX_HEARTBEAT; + ls1x_wdt->parent = &pdev->dev; + watchdog_set_nowayout(ls1x_wdt, nowayout); + watchdog_set_drvdata(ls1x_wdt, drvdata); + + ret = watchdog_register_device(&drvdata->wdt); + if (ret < 0) { + dev_err(&pdev->dev, "failed to register watchdog device\n"); + return ret; + } + + platform_set_drvdata(pdev, drvdata); + + return 0; +} + +static int ls1x_wdt_remove(struct platform_device *pdev) +{ + struct ls1x_wdt_drvdata *drvdata = platform_get_drvdata(pdev); + + ls1x_wdt_stop(&drvdata->wdt); + watchdog_unregister_device(&drvdata->wdt); + clk_disable_unprepare(drvdata->clk); + + return 0; +} + +static struct platform_driver ls1x_wdt_driver = { + .probe = ls1x_wdt_probe, + .remove = ls1x_wdt_remove, + .driver = { + .name = "ls1x-wdt", + }, +}; + +module_platform_driver(ls1x_wdt_driver); + +MODULE_AUTHOR("Yang Ling <gnaygnil@xxxxxxxxx>"); +MODULE_DESCRIPTION("Loongson1 Watchdog Driver"); +MODULE_LICENSE("GPL"); -- 1.9.1