Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4BF18C6FD20 for ; Wed, 8 Mar 2023 03:41:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229456AbjCHDkz convert rfc822-to-8bit (ORCPT ); Tue, 7 Mar 2023 22:40:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43122 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229887AbjCHDks (ORCPT ); Tue, 7 Mar 2023 22:40:48 -0500 Received: from fd01.gateway.ufhost.com (fd01.gateway.ufhost.com [61.152.239.71]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B8D4495451; Tue, 7 Mar 2023 19:40:40 -0800 (PST) Received: from EXMBX165.cuchost.com (unknown [175.102.18.54]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "EXMBX165", Issuer "EXMBX165" (not verified)) by fd01.gateway.ufhost.com (Postfix) with ESMTP id 7F67424E320; Wed, 8 Mar 2023 11:40:39 +0800 (CST) Received: from EXMBX061.cuchost.com (172.16.6.61) by EXMBX165.cuchost.com (172.16.6.75) with Microsoft SMTP Server (TLS) id 15.0.1497.42; Wed, 8 Mar 2023 11:40:39 +0800 Received: from localhost.localdomain (183.27.97.46) by EXMBX061.cuchost.com (172.16.6.61) with Microsoft SMTP Server (TLS) id 15.0.1497.42; Wed, 8 Mar 2023 11:40:38 +0800 From: Xingyu Wu To: , , , Wim Van Sebroeck , Guenter Roeck , Krzysztof Kozlowski , Emil Renner Berthing , Conor Dooley CC: Rob Herring , Paul Walmsley , Palmer Dabbelt , Albert Ou , Philipp Zabel , Xingyu Wu , Samin Guo , Subject: [PATCH v4 2/3] drivers: watchdog: Add StarFive Watchdog driver Date: Wed, 8 Mar 2023 11:40:35 +0800 Message-ID: <20230308034036.99213-3-xingyu.wu@starfivetech.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230308034036.99213-1-xingyu.wu@starfivetech.com> References: <20230308034036.99213-1-xingyu.wu@starfivetech.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [183.27.97.46] X-ClientProxiedBy: EXCAS066.cuchost.com (172.16.6.26) To EXMBX061.cuchost.com (172.16.6.61) X-YovoleRuleAgent: yovoleflag Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add watchdog driver for the StarFive JH7100 and JH7110 SoC. Signed-off-by: Xingyu Wu --- MAINTAINERS | 7 + drivers/watchdog/Kconfig | 9 + drivers/watchdog/Makefile | 2 + drivers/watchdog/starfive-wdt.c | 675 ++++++++++++++++++++++++++++++++ 4 files changed, 693 insertions(+) create mode 100644 drivers/watchdog/starfive-wdt.c diff --git a/MAINTAINERS b/MAINTAINERS index 8d5bc223f305..721d0e4e8a0d 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -19962,6 +19962,13 @@ S: Supported F: Documentation/devicetree/bindings/rng/starfive* F: drivers/char/hw_random/jh7110-trng.c +STARFIVE WATCHDOG DRIVER +M: Xingyu Wu +M: Samin Guo +S: Supported +F: Documentation/devicetree/bindings/watchdog/starfive* +F: drivers/watchdog/starfive-wdt.c + STATIC BRANCH/CALL M: Peter Zijlstra M: Josh Poimboeuf diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index f0872970daf9..9d825ffaf292 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -2090,6 +2090,15 @@ config UML_WATCHDOG tristate "UML watchdog" depends on UML || COMPILE_TEST +config STARFIVE_WATCHDOG + tristate "StarFive Watchdog support" + depends on ARCH_STARFIVE || COMPILE_TEST + select WATCHDOG_CORE + default ARCH_STARFIVE + help + Say Y here to support the watchdog of StarFive JH7100 and JH7110 + SoC. This driver can also be built as a module if choose M. + # # ISA-based Watchdog Cards # diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 9cbf6580f16c..4c0bd377e92a 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -211,6 +211,8 @@ obj-$(CONFIG_WATCHDOG_SUN4V) += sun4v_wdt.o # Xen obj-$(CONFIG_XEN_WDT) += xen_wdt.o +obj-$(CONFIG_STARFIVE_WATCHDOG) += starfive-wdt.o + # Architecture Independent obj-$(CONFIG_BD957XMUF_WATCHDOG) += bd9576_wdt.o obj-$(CONFIG_DA9052_WATCHDOG) += da9052_wdt.o diff --git a/drivers/watchdog/starfive-wdt.c b/drivers/watchdog/starfive-wdt.c new file mode 100644 index 000000000000..8ce9f985f068 --- /dev/null +++ b/drivers/watchdog/starfive-wdt.c @@ -0,0 +1,675 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Starfive Watchdog driver + * + * Copyright (C) 2022 StarFive Technology Co., Ltd. + */ + +#include +#include +#include +#include +#include +#include +#include + +/* JH7100 Watchdog register define */ +#define STARFIVE_WDT_JH7100_INTSTAUS 0x000 /* RO: [4]: Watchdog Interrupt status */ +#define STARFIVE_WDT_JH7100_CONTROL 0x104 /* RW: reset enable */ +#define STARFIVE_WDT_JH7100_LOAD 0x108 /* RW: Watchdog Load register */ +#define STARFIVE_WDT_JH7100_EN 0x110 /* RW: Watchdog Enable Register */ +#define STARFIVE_WDT_JH7100_RELOAD 0x114 /* RW: Write 0 or 1 to reload preset value */ +#define STARFIVE_WDT_JH7100_VALUE 0x118 /* RO: The current value for watchdog counter */ +#define STARFIVE_WDT_JH7100_INTCLR 0x120 /* + * RW: Watchdog Clear Interrupt Register + * [0]: Write 1 to clear interrupt + * [1]: 1 mean clearing and 0 mean complete + */ +#define STARFIVE_WDT_JH7100_LOCK 0x13c /* RW: Lock Register, write 0x378f0765 to unlock */ + +/* JH7110 Watchdog register define */ +#define STARFIVE_WDT_JH7110_LOAD 0x000 /* RW: Watchdog Load register */ +#define STARFIVE_WDT_JH7110_VALUE 0x004 /* RO: The current value for watchdog counter */ +#define STARFIVE_WDT_JH7110_CONTROL 0x008 /* + * RW: + * [0]: reset enable; + * [1]: int enable/wdt enable/reload counter; + * [31:2]: reserved. + */ +#define STARFIVE_WDT_JH7110_INTCLR 0x00c /* WO: clear intterupt && reload the counter */ +#define STARFIVE_WDT_JH7110_IMS 0x014 /* RO: Enabled interrupt status from the counter */ +#define STARFIVE_WDT_JH7110_LOCK 0xc00 /* RW: Lock Register, write 0x1ACCE551 to unlock */ + +/* WDOGCONTROL */ +#define STARFIVE_WDT_ENABLE 0x1 +#define STARFIVE_WDT_EN_SHIFT 0 +#define STARFIVE_WDT_RESET_EN 0x1 +#define STARFIVE_WDT_JH7100_RESEN_SHIFT 0 +#define STARFIVE_WDT_JH7110_RESEN_SHIFT 1 + +/* WDOGLOCK */ +#define STARFIVE_WDT_LOCKED BIT(0) +#define STARFIVE_WDT_JH7100_UNLOCK_KEY 0x378f0765 +#define STARFIVE_WDT_JH7110_UNLOCK_KEY 0x1acce551 + +/* WDOGINTCLR */ +#define STARFIVE_WDT_INTCLR 0x1 +#define STARFIVE_WDT_JH7100_INTCLR_AVA_SHIFT 1 /* Watchdog can clear interrupt when 0 */ + +#define STARFIVE_WDT_MAXCNT 0xffffffff +#define STARFIVE_WDT_DEFAULT_TIME (15) +#define STARFIVE_WDT_DELAY_US 0 +#define STARFIVE_WDT_TIMEOUT_US 10000 + +/* module parameter */ +#define STARFIVE_WDT_EARLY_ENA 0 + +static bool nowayout = WATCHDOG_NOWAYOUT; +static int heartbeat; +static bool early_enable = STARFIVE_WDT_EARLY_ENA; + +module_param(heartbeat, int, 0); +module_param(early_enable, bool, 0); +module_param(nowayout, bool, 0); + +MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (default=" + __MODULE_STRING(STARFIVE_WDT_DEFAULT_TIME) ")"); +MODULE_PARM_DESC(early_enable, + "Watchdog is started at boot time if set to 1, default=" + __MODULE_STRING(STARFIVE_WDT_EARLY_ENA)); +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" + __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); + +struct starfive_wdt_variant { + /* resgister */ + unsigned int control; + unsigned int load; + unsigned int reload; + unsigned int enable; + unsigned int value; + unsigned int int_clr; + unsigned int unlock; + unsigned int int_status; + + u32 unlock_key; + u8 enrst_shift; + u8 en_shift; + bool intclr_check; /* whether need to check it before clearing interrupt */ + u8 intclr_ava_shift; + bool double_timeout; /* The watchdog need twice timeout to reboot */ +}; + +struct starfive_wdt { + unsigned long freq; + struct device *dev; + struct watchdog_device wdt_device; + struct clk *core_clk; + struct clk *apb_clk; + struct reset_control *rsts; + u32 count; /*count of timeout*/ + u32 reload; /*restore the count*/ + void __iomem *base; + spinlock_t lock; /* spinlock for register handling */ + const struct starfive_wdt_variant *drv_data; +}; + +/* Register layout and configuration for the JH7100 */ +static const struct starfive_wdt_variant drv_data_jh7100 = { + .control = STARFIVE_WDT_JH7100_CONTROL, + .load = STARFIVE_WDT_JH7100_LOAD, + .reload = STARFIVE_WDT_JH7100_RELOAD, + .enable = STARFIVE_WDT_JH7100_EN, + .value = STARFIVE_WDT_JH7100_VALUE, + .int_clr = STARFIVE_WDT_JH7100_INTCLR, + .unlock = STARFIVE_WDT_JH7100_LOCK, + .unlock_key = STARFIVE_WDT_JH7100_UNLOCK_KEY, + .int_status = STARFIVE_WDT_JH7100_INTSTAUS, + .enrst_shift = STARFIVE_WDT_JH7100_RESEN_SHIFT, + .en_shift = STARFIVE_WDT_EN_SHIFT, + .intclr_check = true, + .intclr_ava_shift = STARFIVE_WDT_JH7100_INTCLR_AVA_SHIFT, + .double_timeout = false, +}; + +/* Register layout and configuration for the JH7110 */ +static const struct starfive_wdt_variant drv_data_jh7110 = { + .control = STARFIVE_WDT_JH7110_CONTROL, + .load = STARFIVE_WDT_JH7110_LOAD, + .enable = STARFIVE_WDT_JH7110_CONTROL, + .value = STARFIVE_WDT_JH7110_VALUE, + .int_clr = STARFIVE_WDT_JH7110_INTCLR, + .unlock = STARFIVE_WDT_JH7110_LOCK, + .unlock_key = STARFIVE_WDT_JH7110_UNLOCK_KEY, + .int_status = STARFIVE_WDT_JH7110_IMS, + .enrst_shift = STARFIVE_WDT_JH7110_RESEN_SHIFT, + .en_shift = STARFIVE_WDT_EN_SHIFT, + .intclr_check = false, + .double_timeout = true, +}; + +static const struct of_device_id starfive_wdt_match[] = { + { .compatible = "starfive,jh7100-wdt", .data = &drv_data_jh7100 }, + { .compatible = "starfive,jh7110-wdt", .data = &drv_data_jh7110 }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, starfive_wdt_match); + +static int starfive_wdt_get_clock_rate(struct starfive_wdt *wdt) +{ + wdt->freq = clk_get_rate(wdt->core_clk); + if (!wdt->freq) { + dev_err(wdt->dev, "get clock rate failed.\n"); + return -EINVAL; + } + + return 0; +} + +static int starfive_wdt_enable_clock(struct starfive_wdt *wdt) +{ + int ret; + + ret = clk_prepare_enable(wdt->apb_clk); + if (ret) + return dev_err_probe(wdt->dev, ret, "failed to enable apb_clk.\n"); + + ret = clk_prepare_enable(wdt->core_clk); + if (ret) + return dev_err_probe(wdt->dev, ret, "failed to enable core_clk.\n"); + + return 0; +} + +static void starfive_wdt_disable_clock(struct starfive_wdt *wdt) +{ + clk_disable_unprepare(wdt->core_clk); + clk_disable_unprepare(wdt->apb_clk); +} + +static int starfive_wdt_get_clock(struct starfive_wdt *wdt) +{ + wdt->apb_clk = devm_clk_get(wdt->dev, "apb"); + if (IS_ERR(wdt->apb_clk)) + return dev_err_probe(wdt->dev, PTR_ERR(wdt->apb_clk), + "failed to get apb clock.\n"); + + wdt->core_clk = devm_clk_get(wdt->dev, "core"); + if (IS_ERR(wdt->core_clk)) + return dev_err_probe(wdt->dev, PTR_ERR(wdt->core_clk), + "failed to get core clock.\n"); + + return 0; +} + +static int starfive_wdt_reset_init(struct starfive_wdt *wdt) +{ + int ret; + + wdt->rsts = devm_reset_control_array_get_exclusive(wdt->dev); + if (IS_ERR(wdt->rsts)) + return dev_err_probe(wdt->dev, PTR_ERR(wdt->rsts), + "failed to get resets.\n"); + + ret = reset_control_deassert(wdt->rsts); + if (ret) + return dev_err_probe(wdt->dev, ret, + "failed to deassert resets.\n"); + + return 0; +} + +static u32 starfive_wdt_ticks_to_sec(struct starfive_wdt *wdt, u32 ticks) +{ + return DIV_ROUND_CLOSEST(ticks, wdt->freq); +} + +/* + * Write unlock-key to unlock. Write other value to lock. When lock bit is 1, + * external accesses to other watchdog registers are ignored. + */ +static bool starfive_wdt_is_locked(struct starfive_wdt *wdt) +{ + u32 val; + + val = readl(wdt->base + wdt->drv_data->unlock); + return !!(val & STARFIVE_WDT_LOCKED); +} + +static void starfive_wdt_unlock(struct starfive_wdt *wdt) +{ + if (starfive_wdt_is_locked(wdt)) + writel(wdt->drv_data->unlock_key, + wdt->base + wdt->drv_data->unlock); +} + +static void starfive_wdt_lock(struct starfive_wdt *wdt) +{ + if (!starfive_wdt_is_locked(wdt)) + writel(~wdt->drv_data->unlock_key, + wdt->base + wdt->drv_data->unlock); +} + +/* enable watchdog interrupt to reset/reboot */ +static void starfive_wdt_enable_reset(struct starfive_wdt *wdt) +{ + u32 val; + + val = readl(wdt->base + wdt->drv_data->control); + val |= STARFIVE_WDT_RESET_EN << wdt->drv_data->enrst_shift; + writel(val, wdt->base + wdt->drv_data->control); +} + +/* interrupt status whether has been raised from the counter */ +static bool starfive_wdt_raise_irq_status(struct starfive_wdt *wdt) +{ + return !!readl(wdt->base + wdt->drv_data->int_status); +} + +/* waiting interrupt can be free to clear */ +static int starfive_wdt_wait_int_free(struct starfive_wdt *wdt) +{ + u32 value; + + value = readl(wdt->base + wdt->drv_data->int_clr); + return readl_poll_timeout_atomic(wdt->base + wdt->drv_data->int_clr, value, + !(value & BIT(wdt->drv_data->intclr_ava_shift)), + STARFIVE_WDT_DELAY_US, STARFIVE_WDT_TIMEOUT_US); +} + +/* clear interrupt signal before initialization or reload */ +static int starfive_wdt_int_clr(struct starfive_wdt *wdt) +{ + int ret; + + if (wdt->drv_data->intclr_check) { + ret = starfive_wdt_wait_int_free(wdt); + if (ret) + return dev_err_probe(wdt->dev, ret, + "watchdog is not ready to clear interrupt.\n"); + } + writel(STARFIVE_WDT_INTCLR, wdt->base + wdt->drv_data->int_clr); + + return 0; +} + +static inline void starfive_wdt_set_count(struct starfive_wdt *wdt, u32 val) +{ + writel(val, wdt->base + wdt->drv_data->load); +} + +static inline u32 starfive_wdt_get_count(struct starfive_wdt *wdt) +{ + return readl(wdt->base + wdt->drv_data->value); +} + +/* enable watchdog */ +static inline void starfive_wdt_enable(struct starfive_wdt *wdt) +{ + u32 val; + + val = readl(wdt->base + wdt->drv_data->enable); + val |= STARFIVE_WDT_ENABLE << wdt->drv_data->en_shift; + writel(val, wdt->base + wdt->drv_data->enable); +} + +/* disable watchdog */ +static inline void starfive_wdt_disable(struct starfive_wdt *wdt) +{ + u32 val; + + val = readl(wdt->base + wdt->drv_data->enable); + val &= ~(STARFIVE_WDT_ENABLE << wdt->drv_data->en_shift); + writel(val, wdt->base + wdt->drv_data->enable); +} + +static inline void starfive_wdt_set_reload_count(struct starfive_wdt *wdt, u32 count) +{ + starfive_wdt_set_count(wdt, count); + + /* 7100 need set any value to reload register and could reload value to counter */ + if (wdt->drv_data->reload) + writel(0x1, wdt->base + wdt->drv_data->reload); +} + +static unsigned int starfive_wdt_max_timeout(struct starfive_wdt *wdt) +{ + unsigned int timeout_num = wdt->drv_data->double_timeout ? 2 : 1; + + return DIV_ROUND_UP(STARFIVE_WDT_MAXCNT, (wdt->freq / timeout_num)) - 1; +} + +static unsigned int starfive_wdt_get_timeleft(struct watchdog_device *wdd) +{ + struct starfive_wdt *wdt = watchdog_get_drvdata(wdd); + u32 count; + + starfive_wdt_unlock(wdt); + /* + * If the watchdog takes twice timeout and set half count value, + * timeleft value should add the count value before first timeout. + */ + count = starfive_wdt_get_count(wdt); + if (wdt->drv_data->double_timeout && !starfive_wdt_raise_irq_status(wdt)) + count += wdt->count; + + starfive_wdt_lock(wdt); + + return starfive_wdt_ticks_to_sec(wdt, count); +} + +static int starfive_wdt_keepalive(struct watchdog_device *wdd) +{ + struct starfive_wdt *wdt = watchdog_get_drvdata(wdd); + int ret; + + spin_lock(&wdt->lock); + + starfive_wdt_unlock(wdt); + ret = starfive_wdt_int_clr(wdt); + if (ret) + return ret; + + starfive_wdt_set_reload_count(wdt, wdt->count); + starfive_wdt_lock(wdt); + + spin_unlock(&wdt->lock); + + return 0; +} + +static int starfive_wdt_stop(struct watchdog_device *wdd) +{ + struct starfive_wdt *wdt = watchdog_get_drvdata(wdd); + + spin_lock(&wdt->lock); + + starfive_wdt_unlock(wdt); + starfive_wdt_disable(wdt); + starfive_wdt_lock(wdt); + + spin_unlock(&wdt->lock); + + return 0; +} + +static int starfive_wdt_pm_stop(struct watchdog_device *wdd) +{ + struct starfive_wdt *wdt = watchdog_get_drvdata(wdd); + + starfive_wdt_stop(wdd); + pm_runtime_put_sync(wdt->dev); + + return 0; +} + +static int starfive_wdt_start(struct watchdog_device *wdd) +{ + struct starfive_wdt *wdt = watchdog_get_drvdata(wdd); + int ret; + + spin_lock(&wdt->lock); + starfive_wdt_unlock(wdt); + /* disable watchdog, to be safe */ + starfive_wdt_disable(wdt); + + starfive_wdt_enable_reset(wdt); + ret = starfive_wdt_int_clr(wdt); + if (ret) + return ret; + + starfive_wdt_set_count(wdt, wdt->count); + starfive_wdt_enable(wdt); + + starfive_wdt_lock(wdt); + spin_unlock(&wdt->lock); + + return 0; +} + +static int starfive_wdt_pm_start(struct watchdog_device *wdd) +{ + struct starfive_wdt *wdt = watchdog_get_drvdata(wdd); + + pm_runtime_get_sync(wdt->dev); + + return starfive_wdt_start(wdd); +} + +static int starfive_wdt_set_timeout(struct watchdog_device *wdd, + unsigned int timeout) +{ + struct starfive_wdt *wdt = watchdog_get_drvdata(wdd); + unsigned long freq = wdt->freq; + unsigned int timeout_num = wdt->drv_data->double_timeout ? 2 : 1; + + spin_lock(&wdt->lock); + + /* + * This watchdog takes twice timeouts to reset. + * In order to reduce time to reset, should set half count value. + */ + wdt->count = timeout * freq / timeout_num; + wdd->timeout = timeout; + + starfive_wdt_unlock(wdt); + starfive_wdt_disable(wdt); + starfive_wdt_set_reload_count(wdt, wdt->count); + starfive_wdt_enable(wdt); + starfive_wdt_lock(wdt); + + spin_unlock(&wdt->lock); + + return 0; +} + +#define OPTIONS (WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE) + +static const struct watchdog_info starfive_wdt_ident = { + .options = OPTIONS, + .identity = "StarFive Watchdog", +}; + +static const struct watchdog_ops starfive_wdt_ops = { + .owner = THIS_MODULE, + .start = starfive_wdt_pm_start, + .stop = starfive_wdt_pm_stop, + .ping = starfive_wdt_keepalive, + .set_timeout = starfive_wdt_set_timeout, + .get_timeleft = starfive_wdt_get_timeleft, +}; + +static const struct watchdog_device starfive_wdd = { + .info = &starfive_wdt_ident, + .ops = &starfive_wdt_ops, + .timeout = STARFIVE_WDT_DEFAULT_TIME, +}; + +static int starfive_wdt_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct starfive_wdt *wdt; + int ret; + + wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL); + if (!wdt) + return -ENOMEM; + + wdt->dev = dev; + spin_lock_init(&wdt->lock); + wdt->wdt_device = starfive_wdd; + wdt->drv_data = of_device_get_match_data(&pdev->dev); + + /* get the memory region for the watchdog timer */ + wdt->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(wdt->base)) { + ret = PTR_ERR(wdt->base); + return ret; + } + + platform_set_drvdata(pdev, wdt); + pm_runtime_enable(wdt->dev); + + ret = starfive_wdt_get_clock(wdt); + if (ret) + return ret; + + if (pm_runtime_enabled(wdt->dev)) { + ret = pm_runtime_get_sync(wdt->dev); + if (ret < 0) + return ret; + } else { + /* runtime PM is disabled but clocks need to be enabled */ + ret = starfive_wdt_enable_clock(wdt); + if (ret) + return ret; + } + + ret = starfive_wdt_get_clock_rate(wdt); + if (ret) + goto err_exit; + + ret = starfive_wdt_reset_init(wdt); + if (ret) + goto err_exit; + + wdt->wdt_device.min_timeout = 1; + wdt->wdt_device.max_timeout = starfive_wdt_max_timeout(wdt); + + watchdog_set_drvdata(&wdt->wdt_device, wdt); + + wdt->wdt_device.timeout = STARFIVE_WDT_DEFAULT_TIME; + watchdog_init_timeout(&wdt->wdt_device, heartbeat, dev); + starfive_wdt_set_timeout(&wdt->wdt_device, wdt->wdt_device.timeout); + + watchdog_set_nowayout(&wdt->wdt_device, nowayout); + watchdog_stop_on_reboot(&wdt->wdt_device); + watchdog_stop_on_unregister(&wdt->wdt_device); + + wdt->wdt_device.parent = dev; + + if (early_enable) { + starfive_wdt_start(&wdt->wdt_device); + set_bit(WDOG_HW_RUNNING, &wdt->wdt_device.status); + } else { + starfive_wdt_stop(&wdt->wdt_device); + } + + ret = watchdog_register_device(&wdt->wdt_device); + if (ret) + goto err_exit; + + if (!early_enable) + pm_runtime_put_sync(wdt->dev); + + return 0; + +err_exit: + starfive_wdt_disable_clock(wdt); + pm_runtime_disable(wdt->dev); + + return ret; +} + +static int starfive_wdt_remove(struct platform_device *dev) +{ + struct starfive_wdt *wdt = platform_get_drvdata(dev); + + starfive_wdt_stop(&wdt->wdt_device); + watchdog_unregister_device(&wdt->wdt_device); + + if (pm_runtime_enabled(wdt->dev)) + pm_runtime_disable(wdt->dev); + else + /* disable clock without PM */ + starfive_wdt_disable_clock(wdt); + + return 0; +} + +static void starfive_wdt_shutdown(struct platform_device *dev) +{ + struct starfive_wdt *wdt = platform_get_drvdata(dev); + + starfive_wdt_pm_stop(&wdt->wdt_device); +} + +#ifdef CONFIG_PM_SLEEP +static int starfive_wdt_suspend(struct device *dev) +{ + int ret; + struct starfive_wdt *wdt = dev_get_drvdata(dev); + + starfive_wdt_unlock(wdt); + + /* Save watchdog state, and turn it off. */ + wdt->reload = starfive_wdt_get_count(wdt); + + /* Note that WTCNT doesn't need to be saved. */ + starfive_wdt_stop(&wdt->wdt_device); + pm_runtime_force_suspend(dev); + + starfive_wdt_lock(wdt); + + return 0; +} + +static int starfive_wdt_resume(struct device *dev) +{ + int ret; + struct starfive_wdt *wdt = dev_get_drvdata(dev); + + starfive_wdt_unlock(wdt); + + pm_runtime_force_resume(dev); + + /* Restore watchdog state. */ + starfive_wdt_set_reload_count(wdt, wdt->reload); + + starfive_wdt_start(&wdt->wdt_device); + + starfive_wdt_lock(wdt); + + return 0; +} +#endif /* CONFIG_PM_SLEEP */ + +#ifdef CONFIG_PM +static int starfive_wdt_runtime_suspend(struct device *dev) +{ + struct starfive_wdt *wdt = dev_get_drvdata(dev); + + starfive_wdt_disable_clock(wdt); + + return 0; +} + +static int starfive_wdt_runtime_resume(struct device *dev) +{ + struct starfive_wdt *wdt = dev_get_drvdata(dev); + + return starfive_wdt_enable_clock(wdt); +} +#endif /* CONFIG_PM */ + +static const struct dev_pm_ops starfive_wdt_pm_ops = { + SET_RUNTIME_PM_OPS(starfive_wdt_runtime_suspend, starfive_wdt_runtime_resume, NULL) + SET_SYSTEM_SLEEP_PM_OPS(starfive_wdt_suspend, starfive_wdt_resume) +}; + +static struct platform_driver starfive_wdt_driver = { + .probe = starfive_wdt_probe, + .remove = starfive_wdt_remove, + .shutdown = starfive_wdt_shutdown, + .driver = { + .name = "starfive-wdt", + .pm = &starfive_wdt_pm_ops, + .of_match_table = of_match_ptr(starfive_wdt_match), + }, +}; + +module_platform_driver(starfive_wdt_driver); + +MODULE_AUTHOR("Xingyu Wu "); +MODULE_AUTHOR("Samin Guo "); +MODULE_DESCRIPTION("StarFive Watchdog Device Driver"); +MODULE_LICENSE("GPL"); -- 2.25.1