Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754285AbbERRif (ORCPT ); Mon, 18 May 2015 13:38:35 -0400 Received: from mail-ob0-f181.google.com ([209.85.214.181]:34822 "EHLO mail-ob0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753126AbbERRia (ORCPT ); Mon, 18 May 2015 13:38:30 -0400 MIME-Version: 1.0 In-Reply-To: <555679DE.4080502@roeck-us.net> References: <=fu.wei@linaro.org> <1431689090-3125-1-git-send-email-fu.wei@linaro.org> <1431689090-3125-2-git-send-email-fu.wei@linaro.org> <555679DE.4080502@roeck-us.net> Date: Tue, 19 May 2015 01:38:29 +0800 Message-ID: Subject: Re: [PATCH 5/6] Watchdog: introdouce ARM SBSA watchdog driver From: Fu Wei To: Guenter Roeck Cc: Suravee Suthikulpanit , Linaro ACPI Mailman List , linux-watchdog@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, Wei Fu , G Gregory , Al Stone , Hanjun Guo , Timur Tabi , Ashwin Chaugule , Arnd Bergmann , vgandhi@codeaurora.org, wim@iguana.be, Jon Masters , Leo Duran , Jon Corbet Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 25819 Lines: 846 Hi Grenter, Great thanks for your review, On 16 May 2015 at 06:57, Guenter Roeck wrote: > On 05/15/2015 04:24 AM, fu.wei@linaro.org wrote: >> >> From: Fu Wei >> >> (1)Use linux kernel watchdog framework >> (2)Work with FDT on ARM64 >> (3)Use "pretimeout" in watchdog framework >> (4)In first timeout(WS0), do panic to save system context >> (5)support geting timeout and pretimeout from > > > getting > >> parameter and FDT at the driver init stage. > > > Subject: s/introdouce/introduce/ > > Please find a better description. > > Also, please provide revisions numbers for your patch sets, and > list the changes from one revision to the next. sorry for those typo, I have fixed them, and will provide revisions numbers and changelog in next patch > >> >> Signed-off-by: Fu Wei >> --- >> drivers/watchdog/Kconfig | 10 + >> drivers/watchdog/Makefile | 1 + >> drivers/watchdog/sbsa_gwdt.c | 553 >> +++++++++++++++++++++++++++++++++++++++++++ >> 3 files changed, 564 insertions(+) >> create mode 100644 drivers/watchdog/sbsa_gwdt.c >> >> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig >> index e5e7c55..1e1bc8b 100644 >> --- a/drivers/watchdog/Kconfig >> +++ b/drivers/watchdog/Kconfig >> @@ -152,6 +152,16 @@ config ARM_SP805_WATCHDOG >> ARM Primecell SP805 Watchdog timer. This will reboot your system >> when >> the timeout is reached. >> >> +config ARM_SBSA_WATCHDOG >> + tristate "ARM SBSA Generic Watchdog" >> + depends on ARM || ARM64 || COMPILE_TEST >> + select WATCHDOG_CORE >> + help >> + ARM SBSA Generic Watchdog timer. This has two Watchdog >> Signal(WS0/WS1), > > > signals > >> + will trigger a warnning interrupt(do panic) in the first >> timeout(WS0); > > > warning sorry for these typoes, I have fixed them, > > >> + will reboot your system when the second timeout(WS1) is reached. >> + More details: DEN0029B - Server Base System Architecture (SBSA) >> + >> config AT91RM9200_WATCHDOG >> tristate "AT91RM9200 watchdog" >> depends on SOC_AT91RM9200 && MFD_SYSCON >> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile >> index 5c19294..471f1b7c 100644 >> --- a/drivers/watchdog/Makefile >> +++ b/drivers/watchdog/Makefile >> @@ -30,6 +30,7 @@ obj-$(CONFIG_USBPCWATCHDOG) += pcwd_usb.o >> >> # ARM Architecture >> obj-$(CONFIG_ARM_SP805_WATCHDOG) += sp805_wdt.o >> +obj-$(CONFIG_ARM_SBSA_WATCHDOG) += sbsa_gwdt.o >> obj-$(CONFIG_AT91RM9200_WATCHDOG) += at91rm9200_wdt.o >> obj-$(CONFIG_AT91SAM9X_WATCHDOG) += at91sam9_wdt.o >> obj-$(CONFIG_CADENCE_WATCHDOG) += cadence_wdt.o >> diff --git a/drivers/watchdog/sbsa_gwdt.c b/drivers/watchdog/sbsa_gwdt.c >> new file mode 100644 >> index 0000000..52838b1 >> --- /dev/null >> +++ b/drivers/watchdog/sbsa_gwdt.c >> @@ -0,0 +1,553 @@ >> +/* >> + * SBSA(Server Base System Architecture) Generic Watchdog driver >> + * >> + * Copyright (c) 2015, Linaro Ltd. >> + * Author: Fu Wei >> + * Suravee Suthikulpanit >> + * >> + * This program is free software; you can redistribute it and/or modify >> + * it under the terms of the GNU General Public License 2 as published >> + * by the Free Software Foundation. >> + * >> + * 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. >> + * >> + * Note: This SBSA Generic watchdog driver is compatible with >> + * the pretimeout concept of Linux kernel. >> + * But timeout and pretimeout are set by the different REGs. > > > Why "But" ? deleted it :-) > >> + * The first watch period is set by writing WCV directly, >> + * that can support more than 10s timeout at the maximum >> + * system counter frequency. >> + * And the second watch period is set by WOR(32bit) which will be >> loaded > > > s/And the/The/ Thanks, I have fixed them, > > >> + * automatically by hardware, when WS0 is triggered. >> + * This gives a maximum watch period of around 10s at the maximum >> + * system counter frequency. >> + * The System Counter shall run at maximum of 400MHz. >> + * More details: DEN0029B - Server Base System Architecture (SBSA) >> + * >> + * Kernel/API: P---------| pretimeout >> + * |-------------------------------T timeout >> + * SBSA GWDT: P--WOR---WS1 pretimeout >> + * |-------WCV----------WS0~~~~~~~~T timeout >> + */ >> + >> +#include >> + >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> + >> +/* SBSA Generic Watchdog register definitions */ >> +/* refresh frame */ >> +#define SBSA_GWDT_WRR 0x000 >> + >> +/* control frame */ >> +#define SBSA_GWDT_WCS 0x000 >> +#define SBSA_GWDT_WOR 0x008 >> +#define SBSA_GWDT_WCV_LO 0x010 >> +#define SBSA_GWDT_WCV_HI 0x014 >> + >> +/* refresh/control frame */ >> +#define SBSA_GWDT_W_IIDR 0xfcc >> +#define SBSA_GWDT_IDR 0xfd0 >> + >> +/* Watchdog Control and Status Register */ >> +#define SBSA_GWDT_WCS_EN BIT(0) >> +#define SBSA_GWDT_WCS_WS0 BIT(1) >> +#define SBSA_GWDT_WCS_WS1 BIT(2) >> + >> +/* Watchdog Interface Identification Register */ >> +#define SBSA_GWDT_W_IIDR_PID(x) ((x >> 20) & >> 0xfff) >> +#define SBSA_GWDT_W_IIDR_ARCH_VER(x) ((x >> 16) & 0xf) >> +#define SBSA_GWDT_W_IIDR_REV(x) ((x >> 12) & 0xf) >> +#define SBSA_GWDT_W_IIDR_IMPLEMENTER(x) (x & 0xfff) >> +#define SBSA_GWDT_W_IIDR_VID_BANK(x) ((x >> 8) & 0xf) >> +#define SBSA_GWDT_W_IIDR_VID(x) (x & 0x7f) >> + >> +/* Watchdog Identification Register */ >> +#define SBSA_GWDT_IDR_W_PIDR2 0xfe8 >> +#define SBSA_GWDT_IDR_W_PIDR2_ARCH_VER(x) ((x >> 4) & 0xf) >> + > > > (x) for all the above macros, please. Great thanks , my bad , I have fixed them > >> +/** >> + * struct sbsa_gwdt - Internal representation of the SBSA GWDT >> + * @wdd: kernel watchdog_device structure >> + * @clk: store the System Counter clock frequency, in Hz. >> + * @refresh_base: VA of the watchdog refresh frame >> + * @control_base: VA of the watchdog control frame > > > Please spell out "Virtual address". done :-) > >> + * @lock: struct sbsa_gwdt spinlock >> + * @pm_status_store: store the PM info of WDT >> + */ >> +struct sbsa_gwdt { >> + struct watchdog_device wdd; >> + u32 clk; >> + void __iomem *refresh_base; >> + void __iomem *control_base; >> +#ifdef CONFIG_PM_SLEEP >> + spinlock_t lock; >> + u8 pm_status_store; >> +#endif > > > Please avoid the #ifdef I have deleted them , thanks > > >> +}; >> + >> +#define to_sbsa_gwdt(e) container_of(e, struct sbsa_gwdt, wdd) >> + >> +#define DEFAULT_TIMEOUT_WS0 10 /* seconds, the 1st watch period*/ >> +#define DEFAULT_PRETIMEOUT 5 /* seconds, the 2nd watch period*/ >> + >> +static unsigned int timeout; >> +module_param(timeout, uint, 0); >> +MODULE_PARM_DESC(timeout, >> + "Watchdog timeout in seconds. (>=0, default=" >> + __MODULE_STRING(DEFAULT_TIMEOUT_WS0 + DEFAULT_PRETIMEOUT) >> ")"); >> + >> +static unsigned int max_timeout = UINT_MAX; >> +module_param(max_timeout, uint, 0); >> +MODULE_PARM_DESC(max_timeout, >> + "Watchdog max timeout in seconds. (>=0, default=" >> + __MODULE_STRING(UINT_MAX) ")"); >> + >> +static unsigned int max_pretimeout = U32_MAX; >> +module_param(max_pretimeout, uint, 0); >> +MODULE_PARM_DESC(max_pretimeout, >> + "Watchdog max pretimeout in seconds. (>=0, default=" >> + __MODULE_STRING(U32_MAX) ")"); >> + >> +static unsigned int pretimeout; >> +module_param(pretimeout, uint, 0); >> +MODULE_PARM_DESC(pretimeout, >> + "Watchdog pretimeout in seconds. (>=0, default=" >> + __MODULE_STRING(DEFAULT_PRETIMEOUT) ")"); >> + >> +static bool nowayout = WATCHDOG_NOWAYOUT; >> +module_param(nowayout, bool, S_IRUGO); >> +MODULE_PARM_DESC(nowayout, >> + "Watchdog cannot be stopped once started (default=" >> + __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); >> + >> +/* >> + * Architected system timer support. >> + */ >> +static void sbsa_gwdt_cf_write(unsigned int reg, u32 val, >> + struct watchdog_device *wdd) >> +{ >> + struct sbsa_gwdt *gwdt = to_sbsa_gwdt(wdd); >> + >> + writel_relaxed(val, gwdt->control_base + reg); >> +} >> + >> +static void sbsa_gwdt_rf_write(unsigned int reg, u32 val, >> + struct watchdog_device *wdd) >> +{ >> + struct sbsa_gwdt *gwdt = to_sbsa_gwdt(wdd); >> + >> + writel_relaxed(val, gwdt->refresh_base + reg); >> +} >> + >> +static u32 sbsa_gwdt_cf_read(unsigned int reg, struct watchdog_device >> *wdd) >> +{ >> + struct sbsa_gwdt *gwdt = to_sbsa_gwdt(wdd); >> + >> + return readl_relaxed(gwdt->control_base + reg); >> +} >> + >> +/* >> + * help founctions for accessing 64bit WCV register >> + * mutex_lock must be called prior to calling this function. >> + */ >> +static u64 sbsa_gwdt_get_wcv(struct watchdog_device *wdd) >> +{ >> + u32 wcv_lo, wcv_hi; >> + >> + do { >> + wcv_hi = sbsa_gwdt_cf_read(SBSA_GWDT_WCV_HI, wdd); >> + wcv_lo = sbsa_gwdt_cf_read(SBSA_GWDT_WCV_LO, wdd); >> + } while (wcv_hi != sbsa_gwdt_cf_read(SBSA_GWDT_WCV_HI, wdd)); >> + >> + return (((u64)wcv_hi << 32) | wcv_lo); >> +} >> + >> +static void sbsa_gwdt_set_wcv(struct watchdog_device *wdd, u64 value) >> +{ >> + u32 wcv_lo, wcv_hi; >> + >> + wcv_lo = value & U32_MAX; >> + wcv_hi = (value >> 32) & U32_MAX; >> + >> + sbsa_gwdt_cf_write(SBSA_GWDT_WCV_HI, wcv_hi, wdd); >> + sbsa_gwdt_cf_write(SBSA_GWDT_WCV_LO, wcv_lo, wdd); >> + >> + pr_debug("sbsa_gwdt: set WCV to %llu, result: %llu\n", >> + value, sbsa_gwdt_get_wcv(wdd)); > > > Is this pr_debug still necessary ? will remove it , Thanks > > >> +} >> + >> +static void reload_timeout_to_wcv(struct watchdog_device *wdd) >> +{ >> + struct sbsa_gwdt *gwdt = to_sbsa_gwdt(wdd); >> + u64 wcv; >> + >> + wcv = arch_counter_get_cntvct() + >> + (u64)(wdd->timeout - wdd->pretimeout) * gwdt->clk; >> + >> + sbsa_gwdt_set_wcv(wdd, wcv); >> +} >> + >> +/* >> + * Use the following function to set the limit of timeout >> + * after updating pretimeout >> + */ >> +static void sbsa_gwdt_set_timeout_limits(struct sbsa_gwdt *gwdt) >> +{ >> + unsigned int first_period_max = (U64_MAX / gwdt->clk); >> + struct watchdog_device *wdd = &gwdt->wdd; >> + >> + wdd->min_timeout = wdd->pretimeout + 1; >> + wdd->max_timeout = min(wdd->pretimeout + first_period_max, >> max_timeout); >> + >> + pr_debug("sbsa_gwdt: timeout (%u-%u), pretimeout (%u-%u)\n", >> + wdd->min_timeout, wdd->max_timeout, >> + wdd->min_pretimeout, wdd->max_pretimeout); > > > Is this still necessary ? will remove it , Thanks > >> +} >> + >> +static int sbsa_gwdt_set_timeout(struct watchdog_device *wdd, >> + unsigned int timeout) >> +{ >> + wdd->timeout = timeout; >> + >> + return 0; >> + /* watchdog framework will trigger a ping, after this call */ > > > Unnecessary comment. will remove it , Thanks > >> +} >> + >> +static int sbsa_gwdt_set_pretimeout(struct watchdog_device *wdd, >> + unsigned int pretimeout) >> +{ >> + struct sbsa_gwdt *gwdt = to_sbsa_gwdt(wdd); >> + u32 wor; >> + >> + wdd->pretimeout = pretimeout; >> + sbsa_gwdt_set_timeout_limits(gwdt); >> + >> + if (!pretimeout) >> + /* gives sbsa_gwdt_start a chance to setup timeout */ >> + wor = gwdt->clk; >> + else >> + wor = pretimeout * gwdt->clk; >> + >> + /* refresh the WOR, that will cause an explicit watchdog refresh >> */ >> + sbsa_gwdt_cf_write(SBSA_GWDT_WOR, wor, wdd); >> + >> + pr_debug("sbsa_gwdt: set WOR to %x(%us), result: %x\n", >> + wor, pretimeout, sbsa_gwdt_cf_read(SBSA_GWDT_WOR, wdd)); > > > Is this still necessary ? will remove it , Thanks > >> + >> + return 0; >> + /* watchdog framework will trigger a ping, after this call */ > > > Unnecessary comment. will remove it , Thanks > >> +} >> + >> +static unsigned int sbsa_gwdt_get_timeleft(struct watchdog_device *wdd) >> +{ >> + struct sbsa_gwdt *gwdt = to_sbsa_gwdt(wdd); >> + u64 timeleft = sbsa_gwdt_get_wcv(wdd) - arch_counter_get_cntvct(); >> + >> + return timeleft / gwdt->clk; > > > Will this ever be built on a 32 bit target ? That may cause a link error > due to the 64 bit divide operation. yes, you are right, you found a bug, I have fixed it by do_div(). Great thanks !! > >> +} >> + >> +static int sbsa_gwdt_start(struct watchdog_device *wdd) >> +{ >> + /* Force refresh */ >> + sbsa_gwdt_rf_write(SBSA_GWDT_WRR, 0xc0ffee, wdd); >> + /* writing WCS will cause an explicit watchdog refresh */ >> + sbsa_gwdt_cf_write(SBSA_GWDT_WCS, SBSA_GWDT_WCS_EN, wdd); >> + >> + reload_timeout_to_wcv(wdd); >> + >> + pr_debug("sbsa_gwdt: WCS is %x(%s)\n", >> + sbsa_gwdt_cf_read(SBSA_GWDT_WCS, wdd), __func__); > > > Another one. If you think you need to keep those, can you at least use > dev_dbg ? > I won't comment on the debug messages further, but I really think that even > for debug messages this is a bit noisy. will remove it , Thanks > > >> + >> + return 0; >> +} >> + >> +static int sbsa_gwdt_stop(struct watchdog_device *wdd) >> +{ >> + /* Force refresh */ >> + sbsa_gwdt_rf_write(SBSA_GWDT_WRR, 0xc0ffee, wdd); >> + /* writing WCS will cause an explicit watchdog refresh */ >> + sbsa_gwdt_cf_write(SBSA_GWDT_WCS, 0, wdd); >> + >> + pr_debug("sbsa_gwdt: WCS is %x(%s)\n", >> + sbsa_gwdt_cf_read(SBSA_GWDT_WCS, wdd), __func__); >> + >> + return 0; >> +} >> + >> +static int sbsa_gwdt_keepalive(struct watchdog_device *wdd) >> +{ >> + /* >> + * Writing WRR for an explicit watchdog refresh >> + * You can write anyting(like 0xc0ffee) >> + */ >> + sbsa_gwdt_rf_write(SBSA_GWDT_WRR, 0xc0ffee, wdd); >> + >> + reload_timeout_to_wcv(wdd); >> + >> + pr_debug("sbsa_gwdt: ping, %us left.\n", >> sbsa_gwdt_get_timeleft(wdd)); >> + >> + return 0; >> +} >> + >> +static irqreturn_t sbsa_gwdt_interrupt(int irq, void *dev_id) >> +{ >> + struct sbsa_gwdt *gwdt = (struct sbsa_gwdt *)dev_id; >> + struct watchdog_device *wdd = &gwdt->wdd; >> + u32 status; >> + >> + status = sbsa_gwdt_cf_read(SBSA_GWDT_WCS, wdd); >> + >> + pr_debug("sbsa_gwdt: interrupt routine, WCS@%x\n", status); >> + >> + if (status & SBSA_GWDT_WCS_WS0) { >> + pr_debug("sbsa_gwdt WS0: trigger WS1 in %ds!\n", >> + sbsa_gwdt_get_timeleft(wdd)); >> + panic("SBSA Watchdog pre-timeout"); >> + } >> + >> + return IRQ_HANDLED; >> +} >> + >> +static struct watchdog_info sbsa_gwdt_info = { >> + .identity = "SBSA Generic Watchdog", >> + .options = WDIOF_SETTIMEOUT | >> + WDIOF_KEEPALIVEPING | >> + WDIOF_MAGICCLOSE | >> + WDIOF_PRETIMEOUT | >> + WDIOF_CARDRESET, >> +}; >> + >> +static struct watchdog_ops sbsa_gwdt_ops = { >> + .owner = THIS_MODULE, >> + .start = sbsa_gwdt_start, >> + .stop = sbsa_gwdt_stop, >> + .ping = sbsa_gwdt_keepalive, >> + .set_timeout = sbsa_gwdt_set_timeout, >> + .set_pretimeout = sbsa_gwdt_set_pretimeout, >> + .get_timeleft = sbsa_gwdt_get_timeleft, >> +}; >> + >> +static int sbsa_gwdt_probe(struct platform_device *pdev) >> +{ >> + struct device *dev = &pdev->dev; >> + >> + struct sbsa_gwdt *gwdt; >> + struct watchdog_device *wdd; >> + >> + struct resource *res; >> + void *rf_base, *cf_base; >> + int irq; >> + u32 clk, status, w_iidr; >> + >> + int ret = 0; > > > Please drop the empty lines above. OK, np, done :-) > >> + >> + /* >> + * Try to determine the frequency from the cp15 interface >> + */ >> + clk = arch_timer_get_cntfrq(); >> + if (!clk) { >> + dev_err(dev, "System Counter frequency not available\n"); >> + return -EINVAL; >> + } >> + >> + gwdt = devm_kzalloc(dev, sizeof(*gwdt), GFP_KERNEL); >> + if (!gwdt) >> + return -ENOMEM; >> + >> + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, >> "refresh"); >> + rf_base = devm_ioremap_resource(dev, res); >> + if (IS_ERR(rf_base)) >> + return PTR_ERR(rf_base); >> + >> + pr_debug("sbsa_gwdt: ioremap %s frame 0x%llx(size: %llu)-->%p.\n", >> + res->name, (unsigned long long)res->start, >> + (unsigned long long)(res->end - res->start + 1), rf_base); > > > If you think you need to keep those messages, please at least use %pR. thanks for your suggestion, but I will remove it > > >> + >> + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, >> "control"); >> + cf_base = devm_ioremap_resource(dev, res); >> + if (IS_ERR(rf_base)) >> + return PTR_ERR(rf_base); >> + >> + pr_debug("sbsa_gwdt: ioremap %s frame 0x%llx(size: %llu)-->%p.\n", >> + res->name, (unsigned long long)res->start, >> + (unsigned long long)(res->end - res->start + 1), cf_base); >> + >> + irq = platform_get_irq_byname(pdev, "ws0"); >> + if (irq < 0) { >> + dev_err(dev, "unable to get ws0 interrupt.\n"); >> + return irq; >> + } >> + >> + pr_debug("sbsa_gwdt: ws0 irq %d.\n", irq); >> + >> + gwdt->refresh_base = rf_base; >> + gwdt->control_base = cf_base; >> + gwdt->clk = clk; >> +#ifdef CONFIG_PM_SLEEP >> + spin_lock_init(&gwdt->lock); >> +#endif >> + platform_set_drvdata(pdev, gwdt); >> + >> + pr_debug("sbsa_gwdt: hw clk: %uHz--> WOR(32bit) max timeout is >> %us.\n", >> + gwdt->clk, U32_MAX / clk); >> + >> + wdd = &gwdt->wdd; >> + wdd->parent = dev; >> + wdd->info = &sbsa_gwdt_info; >> + wdd->ops = &sbsa_gwdt_ops; >> + watchdog_set_drvdata(wdd, gwdt); >> + watchdog_set_nowayout(wdd, nowayout); >> + >> + status = sbsa_gwdt_cf_read(SBSA_GWDT_WCS, wdd); >> + if (status & SBSA_GWDT_WCS_WS1) { >> + dev_warn(dev, "System was reseted by WDT(WCS: %x, WCV: >> %llx)\n", > > > "was reseted" is kind of odd. Can you use just "reset" or maybe "restarted" > ? yes, will do , thanks > >> + status, sbsa_gwdt_get_wcv(wdd)); >> + wdd->bootstatus |= WDIOF_CARDRESET; >> + } >> + /* Check if watchdog is already enabled */ >> + if (status & SBSA_GWDT_WCS_EN) { >> + dev_warn(dev, "already enabled!\n"); >> + sbsa_gwdt_keepalive(wdd); >> + } >> + >> + pr_debug("sbsa_gwdt: WCS: %x(%s)\n", status, __func__); >> + >> + wdd->min_pretimeout = 0; >> + wdd->max_pretimeout = min(U32_MAX / clk, max_timeout - 1); >> + sbsa_gwdt_set_timeout_limits(gwdt); >> + >> + watchdog_init_pretimeout(wdd, pretimeout, dev); >> + if (!wdd->pretimeout) { >> + wdd->pretimeout = DEFAULT_PRETIMEOUT; >> + dev_info(dev, "can't get pretimeout param, set default >> %us.\n", >> + wdd->pretimeout); > > > Unnecessary message. The pretimeout is printed again below. > >> + } >> + sbsa_gwdt_set_pretimeout(wdd, wdd->pretimeout); >> + >> + watchdog_init_timeout(wdd, timeout, dev); >> + if (!wdd->timeout) { >> + wdd->timeout = wdd->pretimeout + DEFAULT_TIMEOUT_WS0; >> + dev_info(dev, "can't get timeout param, set default: >> %us.\n", >> + wdd->timeout); > > > Same here. > yes, I have removed them. >> + } >> + sbsa_gwdt_set_timeout(wdd, wdd->timeout); >> + >> + ret = devm_request_irq(dev, irq, sbsa_gwdt_interrupt, IRQF_TIMER, >> + pdev->name, gwdt); >> + if (ret) { >> + dev_err(dev, "unable to request IRQ %d\n", irq); >> + return ret; >> + } >> + >> + ret = watchdog_register_device(wdd); >> + if (ret) >> + return ret; >> + >> + /* get device information from control frame and display */ >> + w_iidr = sbsa_gwdt_cf_read(SBSA_GWDT_W_IIDR, &gwdt->wdd); >> + dev_info(dev, "PID:%u(JEP106 %u-%u), Arch v%u Rev %u.", >> + SBSA_GWDT_W_IIDR_PID(w_iidr), >> + SBSA_GWDT_W_IIDR_VID_BANK(w_iidr), >> + SBSA_GWDT_W_IIDR_VID(w_iidr), >> + SBSA_GWDT_W_IIDR_ARCH_VER(w_iidr), >> + SBSA_GWDT_W_IIDR_REV(w_iidr)); > > > Is this valuable information ? not too much value, just tell you the hw info, should I remove it? > > >> + >> + dev_info(dev, "Initialized with %ds timeout, %ds pretimeout @ >> %uHz\n", >> + wdd->timeout, wdd->pretimeout, gwdt->clk); >> + >> + return 0; >> +} >> + >> +static void sbsa_gwdt_shutdown(struct platform_device *pdev) >> +{ >> + struct sbsa_gwdt *gwdt = platform_get_drvdata(pdev); >> + >> + sbsa_gwdt_stop(&gwdt->wdd); >> +} >> + >> +static int sbsa_gwdt_remove(struct platform_device *pdev) >> +{ >> + struct sbsa_gwdt *gwdt = platform_get_drvdata(pdev); >> + int ret = 0; >> + >> + if (!nowayout) >> + ret = sbsa_gwdt_stop(&gwdt->wdd); >> + >> + watchdog_unregister_device(&gwdt->wdd); >> + >> + return ret; >> +} >> + >> +#ifdef CONFIG_PM_SLEEP > > > You don't need the #ifdef if you use __maybe_unused with the function > declarations. yes, doing this way now > >> +/* Disable watchdog if it is active during suspend */ >> +static int sbsa_gwdt_suspend(struct device *dev) >> +{ >> + struct sbsa_gwdt *gwdt = dev_get_drvdata(dev); >> + struct watchdog_device *wdd = &gwdt->wdd; >> + >> + spin_lock(&gwdt->lock); >> + gwdt->pm_status_store = sbsa_gwdt_cf_read(SBSA_GWDT_WCS, wdd); >> + >> + if (gwdt->pm_status_store & SBSA_GWDT_WCS_EN) >> + sbsa_gwdt_stop(wdd); >> + spin_unlock(&gwdt->lock); > > > Wonder what this lock is protecting against. Can you explain ? > I would assume that suspend and resume are mutually exclusive > and don't require locking against each other. > >> + >> + return 0; >> +} >> + >> +/* Enable watchdog and configure it if necessary */ >> +static int sbsa_gwdt_resume(struct device *dev) >> +{ >> + struct sbsa_gwdt *gwdt = dev_get_drvdata(dev); >> + struct watchdog_device *wdd = &gwdt->wdd; >> + >> + spin_lock(&gwdt->lock); >> + if (gwdt->pm_status_store & SBSA_GWDT_WCS_EN) >> + sbsa_gwdt_start(wdd); >> + else >> + sbsa_gwdt_stop(wdd); > > > What is the stop here for ? Thanks , I have improved this part. :-) > > >> + spin_unlock(&gwdt->lock); >> + >> + return 0; >> +} >> +#endif >> + >> +static const struct of_device_id sbsa_gwdt_of_match[] = { >> + { .compatible = "arm,sbsa-gwdt", }, >> + {}, >> +}; >> +MODULE_DEVICE_TABLE(of, sbsa_gwdt_of_match); >> + >> +static const struct dev_pm_ops sbsa_gwdt_pm_ops = { >> + SET_SYSTEM_SLEEP_PM_OPS(sbsa_gwdt_suspend, sbsa_gwdt_resume) >> +}; >> + >> +static struct platform_driver sbsa_gwdt_driver = { >> + .driver = { >> + .name = "sbsa-gwdt", >> + .pm = &sbsa_gwdt_pm_ops, >> + .of_match_table = sbsa_gwdt_of_match, >> + }, >> + .probe = sbsa_gwdt_probe, >> + .remove = sbsa_gwdt_remove, >> + .shutdown = sbsa_gwdt_shutdown, >> +}; >> + >> +module_platform_driver(sbsa_gwdt_driver); >> + >> +MODULE_DESCRIPTION("SBSA Generic Watchdog Driver"); >> +MODULE_AUTHOR("Fu Wei "); >> +MODULE_LICENSE("GPL v2"); >> > -- Best regards, Fu Wei Software Engineer Red Hat Software (Beijing) Co.,Ltd.Shanghai Branch Ph: +86 21 61221326(direct) Ph: +86 186 2020 4684 (mobile) Room 1512, Regus One Corporate Avenue,Level 15, One Corporate Avenue,222 Hubin Road,Huangpu District, Shanghai,China 200021 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/