Hi, Guenter > -----Original Message----- > From: Guenter Roeck [mailto:groeck7@xxxxxxxxx] On Behalf Of Guenter > Roeck > Sent: Tuesday, May 7, 2019 2:28 AM > To: Anson Huang <anson.huang@xxxxxxx> > Cc: robh+dt@xxxxxxxxxx; mark.rutland@xxxxxxx; wim@xxxxxxxxxxxxxxxxxx; > shawnguo@xxxxxxxxxx; s.hauer@xxxxxxxxxxxxxx; kernel@xxxxxxxxxxxxxx; > festevam@xxxxxxxxx; Aisheng Dong <aisheng.dong@xxxxxxx>; > ulf.hansson@xxxxxxxxxx; sboyd@xxxxxxxxxx; Daniel Baluta > <daniel.baluta@xxxxxxx>; Peng Fan <peng.fan@xxxxxxx>; > devicetree@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linux- > watchdog@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; dl-linux- > imx <linux-imx@xxxxxxx> > Subject: Re: [PATCH V3 3/3] watchdog: imx_sc: Add pretimeout support > > On Sun, May 05, 2019 at 02:15:00AM +0000, Anson Huang wrote: > > i.MX system controller watchdog can support pretimeout IRQ via general > > SCU MU IRQ, it depends on IMX_SCU and driver MUST be probed after SCU > > IPC ready, then enable corresponding SCU IRQ group and register SCU > > IRQ notifier, when watchdog pretimeout IRQ fires, SCU MU IRQ will be > > handled and watchdog pretimeout notifier will be called to handle the > > event. > > > > Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx> > > --- > > No change. > > --- > > drivers/watchdog/Kconfig | 1 + > > drivers/watchdog/imx_sc_wdt.c | 114 > > ++++++++++++++++++++++++++++++++++-------- > > 2 files changed, 95 insertions(+), 20 deletions(-) > > > > diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index > > e19960a..dbc74e1 100644 > > --- a/drivers/watchdog/Kconfig > > +++ b/drivers/watchdog/Kconfig > > @@ -710,6 +710,7 @@ config IMX2_WDT > > config IMX_SC_WDT > > tristate "IMX SC Watchdog" > > depends on HAVE_ARM_SMCCC > > + depends on IMX_SCU > > select WATCHDOG_CORE > > help > > This is the driver for the system controller watchdog diff --git > > a/drivers/watchdog/imx_sc_wdt.c b/drivers/watchdog/imx_sc_wdt.c index > > 49848b6..d8493a3 100644 > > --- a/drivers/watchdog/imx_sc_wdt.c > > +++ b/drivers/watchdog/imx_sc_wdt.c > > @@ -4,6 +4,7 @@ > > */ > > > > #include <linux/arm-smccc.h> > > +#include <linux/firmware/imx/sci.h> > > #include <linux/io.h> > > #include <linux/init.h> > > #include <linux/kernel.h> > > @@ -33,11 +34,19 @@ > > > > #define SC_TIMER_WDOG_ACTION_PARTITION 0 > > > > +#define SC_IRQ_WDOG 1 > > +#define SC_IRQ_GROUP_WDOG 1 > > + > > static bool nowayout = WATCHDOG_NOWAYOUT; > module_param(nowayout, > > bool, 0000); MODULE_PARM_DESC(nowayout, "Watchdog cannot be > stopped > > once started (default=" > > __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); > > > > +struct imx_sc_wdt_device { > > + struct watchdog_device wdd; > > + struct notifier_block wdt_notifier; > > +}; > > + > > static int imx_sc_wdt_ping(struct watchdog_device *wdog) { > > struct arm_smccc_res res; > > @@ -85,24 +94,66 @@ static int imx_sc_wdt_set_timeout(struct > watchdog_device *wdog, > > return res.a0 ? -EACCES : 0; > > } > > > > +static int imx_sc_wdt_set_pretimeout(struct watchdog_device *wdog, > > + unsigned int pretimeout) > > +{ > > + struct arm_smccc_res res; > > + > > + arm_smccc_smc(IMX_SIP_TIMER, > IMX_SIP_TIMER_SET_PRETIME_WDOG, > > + pretimeout * 1000, 0, 0, 0, 0, 0, &res); > > + if (res.a0) > > + return -EACCES; > > + > > + wdog->pretimeout = pretimeout; > > + > > + return 0; > > +} > > + > > +static int imx_sc_wdt_notify(struct notifier_block *nb, > > + unsigned long event, void *group) { > > + struct imx_sc_wdt_device *imx_sc_wdd = > > + container_of(nb, > > + struct imx_sc_wdt_device, > > + wdt_notifier); > > + > > + if (event & SC_IRQ_WDOG && > > + *(u8 *)group == SC_IRQ_GROUP_WDOG) > > + watchdog_notify_pretimeout(&imx_sc_wdd->wdd); > > + > > + return 0; > > +} > > + > > +static void imx_sc_wdt_action(void *data) { > > + struct notifier_block *wdt_notifier = data; > > + > > + imx_scu_irq_unregister_notifier(wdt_notifier); > > + imx_scu_irq_group_enable(SC_IRQ_GROUP_WDOG, > > + SC_IRQ_WDOG, > > + false); > > +} > > + > > static const struct watchdog_ops imx_sc_wdt_ops = { > > .owner = THIS_MODULE, > > .start = imx_sc_wdt_start, > > .stop = imx_sc_wdt_stop, > > .ping = imx_sc_wdt_ping, > > .set_timeout = imx_sc_wdt_set_timeout, > > + .set_pretimeout = imx_sc_wdt_set_pretimeout, > > }; > > > > -static const struct watchdog_info imx_sc_wdt_info = { > > +static struct watchdog_info imx_sc_wdt_info = { > > .identity = "i.MX SC watchdog timer", > > .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | > > - WDIOF_MAGICCLOSE | WDIOF_PRETIMEOUT, > > + WDIOF_MAGICCLOSE, > > }; > > > > static int imx_sc_wdt_probe(struct platform_device *pdev) { > > + struct imx_sc_wdt_device *imx_sc_wdd; > > + struct watchdog_device *wdog; > > struct device *dev = &pdev->dev; > > - struct watchdog_device *imx_sc_wdd; > > int ret; > > > > imx_sc_wdd = devm_kzalloc(dev, sizeof(*imx_sc_wdd), GFP_KERNEL); > @@ > > -111,42 +162,65 @@ static int imx_sc_wdt_probe(struct platform_device > > *pdev) > > > > platform_set_drvdata(pdev, imx_sc_wdd); > > > > - imx_sc_wdd->info = &imx_sc_wdt_info; > > - imx_sc_wdd->ops = &imx_sc_wdt_ops; > > - imx_sc_wdd->min_timeout = 1; > > - imx_sc_wdd->max_timeout = MAX_TIMEOUT; > > - imx_sc_wdd->parent = dev; > > - imx_sc_wdd->timeout = DEFAULT_TIMEOUT; > > + wdog = &imx_sc_wdd->wdd; > > + wdog->info = &imx_sc_wdt_info; > > + wdog->ops = &imx_sc_wdt_ops; > > + wdog->min_timeout = 1; > > + wdog->max_timeout = MAX_TIMEOUT; > > + wdog->parent = dev; > > + wdog->timeout = DEFAULT_TIMEOUT; > > > > - watchdog_init_timeout(imx_sc_wdd, 0, dev); > > - watchdog_stop_on_reboot(imx_sc_wdd); > > - watchdog_stop_on_unregister(imx_sc_wdd); > > + watchdog_init_timeout(wdog, 0, dev); > > + watchdog_stop_on_reboot(wdog); > > + watchdog_stop_on_unregister(wdog); > > > > - ret = devm_watchdog_register_device(dev, imx_sc_wdd); > > + ret = devm_watchdog_register_device(dev, wdog); > > if (ret) { > > dev_err(dev, "Failed to register watchdog device\n"); > > return ret; > > } > > > > - return 0; > > + ret = imx_scu_irq_group_enable(SC_IRQ_GROUP_WDOG, > > + SC_IRQ_WDOG, > > + true); > > + if (ret) { > > + dev_warn(dev, "Enable irq failed, pretimeout NOT > supported\n"); > > + return 0; > > + } > > + > > + imx_sc_wdd->wdt_notifier.notifier_call = imx_sc_wdt_notify; > > + ret = imx_scu_irq_register_notifier(&imx_sc_wdd->wdt_notifier); > > + if (ret) { > > + imx_scu_irq_group_enable(SC_IRQ_GROUP_WDOG, > > + SC_IRQ_WDOG, > > + false); > > + dev_warn(dev, > > + "Register irq notifier failed, pretimeout NOT > supported\n"); > > + return 0; > > + } > > + > > + imx_sc_wdt_info.options |= WDIOF_PRETIMEOUT; > > + ret = devm_add_action(dev, imx_sc_wdt_action, > > + &imx_sc_wdd->wdt_notifier); > > This needs devm_add_action_or_reset() because otherwise the notifier > would not be removed, and the interrupt group would not be disabled. Right, fix it in V4. > > > + return ret; > > This should not return an error. Accepting that the notifier can not be > registered and that the irq group can not be enabled but bailing out if > devm_add_action() fails is inconsistent. > Agreed, the pretimeout function should ONLT be enabled after the notifier register, irq group enable and add action all success, so I use below code in V4, please help review, thanks, + + ret = devm_add_action_or_reset(dev, imx_sc_wdt_action, + &imx_sc_wdd->wdt_notifier); + if (!ret) + imx_sc_wdt_info.options |= WDIOF_PRETIMEOUT; + else + dev_warn(dev, "Add action failed, pretimeout NOT supported\n"); + return 0; Anson. > Guenter > > > } > > > > static int __maybe_unused imx_sc_wdt_suspend(struct device *dev) { > > - struct watchdog_device *imx_sc_wdd = dev_get_drvdata(dev); > > + struct imx_sc_wdt_device *imx_sc_wdd = dev_get_drvdata(dev); > > > > - if (watchdog_active(imx_sc_wdd)) > > - imx_sc_wdt_stop(imx_sc_wdd); > > + if (watchdog_active(&imx_sc_wdd->wdd)) > > + imx_sc_wdt_stop(&imx_sc_wdd->wdd); > > > > return 0; > > } > > > > static int __maybe_unused imx_sc_wdt_resume(struct device *dev) { > > - struct watchdog_device *imx_sc_wdd = dev_get_drvdata(dev); > > + struct imx_sc_wdt_device *imx_sc_wdd = dev_get_drvdata(dev); > > > > - if (watchdog_active(imx_sc_wdd)) > > - imx_sc_wdt_start(imx_sc_wdd); > > + if (watchdog_active(&imx_sc_wdd->wdd)) > > + imx_sc_wdt_start(&imx_sc_wdd->wdd); > > > > return 0; > > } > > -- > > 2.7.4 > >
