| Message ID | 20250312-ivo-intel_oc_wdt-v2-1-52d09738cd0b@siemens.com |
|---|---|
| State | New |
| Headers | show |
| Series | Add driver for Intel Over-Clocking Watchdog | expand |
On 3/12/25 08:46, Diogo Ivo wrote: > Add a driver for the Intel Over-Clocking Watchdog found in Intel > Platform Controller (PCH) chipsets. This watchdog is controlled > via a simple single-register interface and would otherwise be > standard except for the presence of a LOCK bit that can only be > set once per power cycle, needing extra handling around it. > > Signed-off-by: Diogo Ivo <diogo.ivo@siemens.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> > --- > v1->v2: > - Split v1 into two patches, adding the ACPI IDs in a separate patch > - Initialize hearbeat module parameter to zero > - Clarify wording around lock handling > - Properly print resource with %pR when failing to obtain it > - Enable compile testing and add dependency on HAS_IOPORT > - Drop unneeded ACPI_PTR() and MODULE_ALIAS() > --- > --- > drivers/watchdog/Kconfig | 11 ++ > drivers/watchdog/Makefile | 1 + > drivers/watchdog/intel_oc_wdt.c | 233 ++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 245 insertions(+) > > diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig > index f81705f8539aa0b12d156a86aae521aa40b4527d..94d058c6c49a19f8fee97d82ceb653b60d1944cd 100644 > --- a/drivers/watchdog/Kconfig > +++ b/drivers/watchdog/Kconfig > @@ -1350,6 +1350,17 @@ config INTEL_MID_WATCHDOG > > To compile this driver as a module, choose M here. > > +config INTEL_OC_WATCHDOG > + tristate "Intel OC Watchdog" > + depends on (X86 || COMPILE_TEST) && ACPI && HAS_IOPORT > + select WATCHDOG_CORE > + help > + Hardware driver for Intel Over-Clocking watchdog present in > + Platform Controller Hub (PCH) chipsets. > + > + To compile this driver as a module, choose M here: the > + module will be called intel_oc_wdt. > + > config ITCO_WDT > tristate "Intel TCO Timer/Watchdog" > depends on X86 && PCI > diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile > index 8411626fa162268e8ccd06349f7193b15a9d281a..3a13f3e80a0f460b99b4f1592fcf17cc6428876b 100644 > --- a/drivers/watchdog/Makefile > +++ b/drivers/watchdog/Makefile > @@ -149,6 +149,7 @@ obj-$(CONFIG_W83977F_WDT) += w83977f_wdt.o > obj-$(CONFIG_MACHZ_WDT) += machzwd.o > obj-$(CONFIG_SBC_EPX_C3_WATCHDOG) += sbc_epx_c3.o > obj-$(CONFIG_INTEL_MID_WATCHDOG) += intel-mid_wdt.o > +obj-$(CONFIG_INTEL_OC_WATCHDOG) += intel_oc_wdt.o > obj-$(CONFIG_INTEL_MEI_WDT) += mei_wdt.o > obj-$(CONFIG_NI903X_WDT) += ni903x_wdt.o > obj-$(CONFIG_NIC7018_WDT) += nic7018_wdt.o > diff --git a/drivers/watchdog/intel_oc_wdt.c b/drivers/watchdog/intel_oc_wdt.c > new file mode 100644 > index 0000000000000000000000000000000000000000..7c0551106981b08f9e1d2eab8f3ddce99a2462aa > --- /dev/null > +++ b/drivers/watchdog/intel_oc_wdt.c > @@ -0,0 +1,233 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Intel OC Watchdog driver > + * > + * Copyright (C) 2025, Siemens > + * Author: Diogo Ivo <diogo.ivo@siemens.com> > + */ > + > +#define DRV_NAME "intel_oc_wdt" > + > +#include <linux/acpi.h> > +#include <linux/bits.h> > +#include <linux/io.h> > +#include <linux/module.h> > +#include <linux/moduleparam.h> > +#include <linux/platform_device.h> > +#include <linux/watchdog.h> > + > +#define INTEL_OC_WDT_TOV GENMASK(9, 0) > +#define INTEL_OC_WDT_MIN_TOV 1 > +#define INTEL_OC_WDT_MAX_TOV 1024 > +#define INTEL_OC_WDT_DEF_TOV 60 > + > +/* > + * One-time writable lock bit. If set forbids > + * modification of itself, _TOV and _EN until > + * next reboot. > + */ > +#define INTEL_OC_WDT_CTL_LCK BIT(12) > + > +#define INTEL_OC_WDT_EN BIT(14) > +#define INTEL_OC_WDT_NO_ICCSURV_STS BIT(24) > +#define INTEL_OC_WDT_ICCSURV_STS BIT(25) > +#define INTEL_OC_WDT_RLD BIT(31) > + > +#define INTEL_OC_WDT_STS_BITS (INTEL_OC_WDT_NO_ICCSURV_STS | \ > + INTEL_OC_WDT_ICCSURV_STS) > + > +#define INTEL_OC_WDT_CTRL_REG(wdt) ((wdt)->ctrl_res->start) > + > +struct intel_oc_wdt { > + struct watchdog_device wdd; > + struct resource *ctrl_res; > + bool locked; > +}; > + > +static int heartbeat; > +module_param(heartbeat, uint, 0); > +MODULE_PARM_DESC(heartbeat, "Watchdog heartbeats in seconds. (default=" > + __MODULE_STRING(WDT_HEARTBEAT) ")"); > + > +static bool nowayout = WATCHDOG_NOWAYOUT; > +module_param(nowayout, bool, 0); > +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" > + __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); > + > +static int intel_oc_wdt_start(struct watchdog_device *wdd) > +{ > + struct intel_oc_wdt *oc_wdt = watchdog_get_drvdata(wdd); > + > + if (oc_wdt->locked) > + return 0; > + > + outl(inl(INTEL_OC_WDT_CTRL_REG(oc_wdt)) | INTEL_OC_WDT_EN, > + INTEL_OC_WDT_CTRL_REG(oc_wdt)); > + > + return 0; > +} > + > +static int intel_oc_wdt_stop(struct watchdog_device *wdd) > +{ > + struct intel_oc_wdt *oc_wdt = watchdog_get_drvdata(wdd); > + > + outl(inl(INTEL_OC_WDT_CTRL_REG(oc_wdt)) & ~INTEL_OC_WDT_EN, > + INTEL_OC_WDT_CTRL_REG(oc_wdt)); > + > + return 0; > +} > + > +static int intel_oc_wdt_ping(struct watchdog_device *wdd) > +{ > + struct intel_oc_wdt *oc_wdt = watchdog_get_drvdata(wdd); > + > + outl(inl(INTEL_OC_WDT_CTRL_REG(oc_wdt)) | INTEL_OC_WDT_RLD, > + INTEL_OC_WDT_CTRL_REG(oc_wdt)); > + > + return 0; > +} > + > +static int intel_oc_wdt_set_timeout(struct watchdog_device *wdd, > + unsigned int t) > +{ > + struct intel_oc_wdt *oc_wdt = watchdog_get_drvdata(wdd); > + > + outl((inl(INTEL_OC_WDT_CTRL_REG(oc_wdt)) & ~INTEL_OC_WDT_TOV) | (t - 1), > + INTEL_OC_WDT_CTRL_REG(oc_wdt)); > + > + wdd->timeout = t; > + > + return 0; > +} > + > +static const struct watchdog_info intel_oc_wdt_info = { > + .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING, > + .identity = DRV_NAME, > +}; > + > +static const struct watchdog_ops intel_oc_wdt_ops = { > + .owner = THIS_MODULE, > + .start = intel_oc_wdt_start, > + .stop = intel_oc_wdt_stop, > + .ping = intel_oc_wdt_ping, > + .set_timeout = intel_oc_wdt_set_timeout, > +}; > + > +static int intel_oc_wdt_setup(struct intel_oc_wdt *oc_wdt) > +{ > + struct watchdog_info *info; > + unsigned long val; > + > + val = inl(INTEL_OC_WDT_CTRL_REG(oc_wdt)); > + > + if (val & INTEL_OC_WDT_STS_BITS) > + oc_wdt->wdd.bootstatus |= WDIOF_CARDRESET; > + > + oc_wdt->locked = !!(val & INTEL_OC_WDT_CTL_LCK); > + > + if (val & INTEL_OC_WDT_EN) { > + /* > + * No need to issue a ping here to "commit" the new timeout > + * value to hardware as the watchdog core schedules one > + * immediately when registering the watchdog. > + */ > + set_bit(WDOG_HW_RUNNING, &oc_wdt->wdd.status); > + > + if (oc_wdt->locked) { > + info = (struct watchdog_info *)&intel_oc_wdt_info; > + /* > + * Set nowayout unconditionally as we cannot stop > + * the watchdog. > + */ > + nowayout = true; > + /* > + * If we are locked read the current timeout value > + * and inform the core we can't change it. > + */ > + oc_wdt->wdd.timeout = (val & INTEL_OC_WDT_TOV) + 1; > + info->options &= ~WDIOF_SETTIMEOUT; > + > + dev_info(oc_wdt->wdd.parent, > + "Register access locked, heartbeat fixed at: %u s\n", > + oc_wdt->wdd.timeout); > + } > + } else if (oc_wdt->locked) { > + /* > + * In case the watchdog is disabled and locked there > + * is nothing we can do with it so just fail probing. > + */ > + return -EACCES; > + } > + > + val &= ~INTEL_OC_WDT_TOV; > + outl(val | (oc_wdt->wdd.timeout - 1), INTEL_OC_WDT_CTRL_REG(oc_wdt)); > + > + return 0; > +} > + > +static int intel_oc_wdt_probe(struct platform_device *pdev) > +{ > + struct device *dev = &pdev->dev; > + struct intel_oc_wdt *oc_wdt; > + struct watchdog_device *wdd; > + int ret; > + > + oc_wdt = devm_kzalloc(&pdev->dev, sizeof(*oc_wdt), GFP_KERNEL); > + if (!oc_wdt) > + return -ENOMEM; > + > + oc_wdt->ctrl_res = platform_get_resource(pdev, IORESOURCE_IO, 0); > + if (!oc_wdt->ctrl_res) { > + dev_err(&pdev->dev, "missing I/O resource\n"); > + return -ENODEV; > + } > + > + if (!devm_request_region(&pdev->dev, oc_wdt->ctrl_res->start, > + resource_size(oc_wdt->ctrl_res), pdev->name)) { > + dev_err(dev, "resource %pR already in use, device disabled\n", > + oc_wdt->ctrl_res); > + return -EBUSY; > + } > + > + wdd = &oc_wdt->wdd; > + wdd->min_timeout = INTEL_OC_WDT_MIN_TOV; > + wdd->max_timeout = INTEL_OC_WDT_MAX_TOV; > + wdd->timeout = INTEL_OC_WDT_DEF_TOV; > + wdd->info = &intel_oc_wdt_info; > + wdd->ops = &intel_oc_wdt_ops; > + wdd->parent = dev; > + > + watchdog_init_timeout(wdd, heartbeat, dev); > + > + ret = intel_oc_wdt_setup(oc_wdt); > + if (ret) > + return ret; > + > + watchdog_set_drvdata(wdd, oc_wdt); > + watchdog_set_nowayout(wdd, nowayout); > + watchdog_stop_on_reboot(wdd); > + watchdog_stop_on_unregister(wdd); > + > + return devm_watchdog_register_device(dev, wdd); > +} > + > +static const struct acpi_device_id intel_oc_wdt_match[] = { > + { "INT3F0D" }, > + { "INTC1099" }, > + { }, > +}; > +MODULE_DEVICE_TABLE(acpi, intel_oc_wdt_match); > + > +static struct platform_driver intel_oc_wdt_platform_driver = { > + .driver = { > + .name = DRV_NAME, > + .acpi_match_table = intel_oc_wdt_match, > + }, > + .probe = intel_oc_wdt_probe, > +}; > + > +module_platform_driver(intel_oc_wdt_platform_driver); > + > +MODULE_AUTHOR("Diogo Ivo <diogo.ivo@siemens.com>"); > +MODULE_LICENSE("GPL"); > +MODULE_DESCRIPTION("Intel OC Watchdog driver"); >
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index f81705f8539aa0b12d156a86aae521aa40b4527d..94d058c6c49a19f8fee97d82ceb653b60d1944cd 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -1350,6 +1350,17 @@ config INTEL_MID_WATCHDOG To compile this driver as a module, choose M here. +config INTEL_OC_WATCHDOG + tristate "Intel OC Watchdog" + depends on (X86 || COMPILE_TEST) && ACPI && HAS_IOPORT + select WATCHDOG_CORE + help + Hardware driver for Intel Over-Clocking watchdog present in + Platform Controller Hub (PCH) chipsets. + + To compile this driver as a module, choose M here: the + module will be called intel_oc_wdt. + config ITCO_WDT tristate "Intel TCO Timer/Watchdog" depends on X86 && PCI diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 8411626fa162268e8ccd06349f7193b15a9d281a..3a13f3e80a0f460b99b4f1592fcf17cc6428876b 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -149,6 +149,7 @@ obj-$(CONFIG_W83977F_WDT) += w83977f_wdt.o obj-$(CONFIG_MACHZ_WDT) += machzwd.o obj-$(CONFIG_SBC_EPX_C3_WATCHDOG) += sbc_epx_c3.o obj-$(CONFIG_INTEL_MID_WATCHDOG) += intel-mid_wdt.o +obj-$(CONFIG_INTEL_OC_WATCHDOG) += intel_oc_wdt.o obj-$(CONFIG_INTEL_MEI_WDT) += mei_wdt.o obj-$(CONFIG_NI903X_WDT) += ni903x_wdt.o obj-$(CONFIG_NIC7018_WDT) += nic7018_wdt.o diff --git a/drivers/watchdog/intel_oc_wdt.c b/drivers/watchdog/intel_oc_wdt.c new file mode 100644 index 0000000000000000000000000000000000000000..7c0551106981b08f9e1d2eab8f3ddce99a2462aa --- /dev/null +++ b/drivers/watchdog/intel_oc_wdt.c @@ -0,0 +1,233 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Intel OC Watchdog driver + * + * Copyright (C) 2025, Siemens + * Author: Diogo Ivo <diogo.ivo@siemens.com> + */ + +#define DRV_NAME "intel_oc_wdt" + +#include <linux/acpi.h> +#include <linux/bits.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/platform_device.h> +#include <linux/watchdog.h> + +#define INTEL_OC_WDT_TOV GENMASK(9, 0) +#define INTEL_OC_WDT_MIN_TOV 1 +#define INTEL_OC_WDT_MAX_TOV 1024 +#define INTEL_OC_WDT_DEF_TOV 60 + +/* + * One-time writable lock bit. If set forbids + * modification of itself, _TOV and _EN until + * next reboot. + */ +#define INTEL_OC_WDT_CTL_LCK BIT(12) + +#define INTEL_OC_WDT_EN BIT(14) +#define INTEL_OC_WDT_NO_ICCSURV_STS BIT(24) +#define INTEL_OC_WDT_ICCSURV_STS BIT(25) +#define INTEL_OC_WDT_RLD BIT(31) + +#define INTEL_OC_WDT_STS_BITS (INTEL_OC_WDT_NO_ICCSURV_STS | \ + INTEL_OC_WDT_ICCSURV_STS) + +#define INTEL_OC_WDT_CTRL_REG(wdt) ((wdt)->ctrl_res->start) + +struct intel_oc_wdt { + struct watchdog_device wdd; + struct resource *ctrl_res; + bool locked; +}; + +static int heartbeat; +module_param(heartbeat, uint, 0); +MODULE_PARM_DESC(heartbeat, "Watchdog heartbeats in seconds. (default=" + __MODULE_STRING(WDT_HEARTBEAT) ")"); + +static bool nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, bool, 0); +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" + __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); + +static int intel_oc_wdt_start(struct watchdog_device *wdd) +{ + struct intel_oc_wdt *oc_wdt = watchdog_get_drvdata(wdd); + + if (oc_wdt->locked) + return 0; + + outl(inl(INTEL_OC_WDT_CTRL_REG(oc_wdt)) | INTEL_OC_WDT_EN, + INTEL_OC_WDT_CTRL_REG(oc_wdt)); + + return 0; +} + +static int intel_oc_wdt_stop(struct watchdog_device *wdd) +{ + struct intel_oc_wdt *oc_wdt = watchdog_get_drvdata(wdd); + + outl(inl(INTEL_OC_WDT_CTRL_REG(oc_wdt)) & ~INTEL_OC_WDT_EN, + INTEL_OC_WDT_CTRL_REG(oc_wdt)); + + return 0; +} + +static int intel_oc_wdt_ping(struct watchdog_device *wdd) +{ + struct intel_oc_wdt *oc_wdt = watchdog_get_drvdata(wdd); + + outl(inl(INTEL_OC_WDT_CTRL_REG(oc_wdt)) | INTEL_OC_WDT_RLD, + INTEL_OC_WDT_CTRL_REG(oc_wdt)); + + return 0; +} + +static int intel_oc_wdt_set_timeout(struct watchdog_device *wdd, + unsigned int t) +{ + struct intel_oc_wdt *oc_wdt = watchdog_get_drvdata(wdd); + + outl((inl(INTEL_OC_WDT_CTRL_REG(oc_wdt)) & ~INTEL_OC_WDT_TOV) | (t - 1), + INTEL_OC_WDT_CTRL_REG(oc_wdt)); + + wdd->timeout = t; + + return 0; +} + +static const struct watchdog_info intel_oc_wdt_info = { + .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING, + .identity = DRV_NAME, +}; + +static const struct watchdog_ops intel_oc_wdt_ops = { + .owner = THIS_MODULE, + .start = intel_oc_wdt_start, + .stop = intel_oc_wdt_stop, + .ping = intel_oc_wdt_ping, + .set_timeout = intel_oc_wdt_set_timeout, +}; + +static int intel_oc_wdt_setup(struct intel_oc_wdt *oc_wdt) +{ + struct watchdog_info *info; + unsigned long val; + + val = inl(INTEL_OC_WDT_CTRL_REG(oc_wdt)); + + if (val & INTEL_OC_WDT_STS_BITS) + oc_wdt->wdd.bootstatus |= WDIOF_CARDRESET; + + oc_wdt->locked = !!(val & INTEL_OC_WDT_CTL_LCK); + + if (val & INTEL_OC_WDT_EN) { + /* + * No need to issue a ping here to "commit" the new timeout + * value to hardware as the watchdog core schedules one + * immediately when registering the watchdog. + */ + set_bit(WDOG_HW_RUNNING, &oc_wdt->wdd.status); + + if (oc_wdt->locked) { + info = (struct watchdog_info *)&intel_oc_wdt_info; + /* + * Set nowayout unconditionally as we cannot stop + * the watchdog. + */ + nowayout = true; + /* + * If we are locked read the current timeout value + * and inform the core we can't change it. + */ + oc_wdt->wdd.timeout = (val & INTEL_OC_WDT_TOV) + 1; + info->options &= ~WDIOF_SETTIMEOUT; + + dev_info(oc_wdt->wdd.parent, + "Register access locked, heartbeat fixed at: %u s\n", + oc_wdt->wdd.timeout); + } + } else if (oc_wdt->locked) { + /* + * In case the watchdog is disabled and locked there + * is nothing we can do with it so just fail probing. + */ + return -EACCES; + } + + val &= ~INTEL_OC_WDT_TOV; + outl(val | (oc_wdt->wdd.timeout - 1), INTEL_OC_WDT_CTRL_REG(oc_wdt)); + + return 0; +} + +static int intel_oc_wdt_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct intel_oc_wdt *oc_wdt; + struct watchdog_device *wdd; + int ret; + + oc_wdt = devm_kzalloc(&pdev->dev, sizeof(*oc_wdt), GFP_KERNEL); + if (!oc_wdt) + return -ENOMEM; + + oc_wdt->ctrl_res = platform_get_resource(pdev, IORESOURCE_IO, 0); + if (!oc_wdt->ctrl_res) { + dev_err(&pdev->dev, "missing I/O resource\n"); + return -ENODEV; + } + + if (!devm_request_region(&pdev->dev, oc_wdt->ctrl_res->start, + resource_size(oc_wdt->ctrl_res), pdev->name)) { + dev_err(dev, "resource %pR already in use, device disabled\n", + oc_wdt->ctrl_res); + return -EBUSY; + } + + wdd = &oc_wdt->wdd; + wdd->min_timeout = INTEL_OC_WDT_MIN_TOV; + wdd->max_timeout = INTEL_OC_WDT_MAX_TOV; + wdd->timeout = INTEL_OC_WDT_DEF_TOV; + wdd->info = &intel_oc_wdt_info; + wdd->ops = &intel_oc_wdt_ops; + wdd->parent = dev; + + watchdog_init_timeout(wdd, heartbeat, dev); + + ret = intel_oc_wdt_setup(oc_wdt); + if (ret) + return ret; + + watchdog_set_drvdata(wdd, oc_wdt); + watchdog_set_nowayout(wdd, nowayout); + watchdog_stop_on_reboot(wdd); + watchdog_stop_on_unregister(wdd); + + return devm_watchdog_register_device(dev, wdd); +} + +static const struct acpi_device_id intel_oc_wdt_match[] = { + { "INT3F0D" }, + { "INTC1099" }, + { }, +}; +MODULE_DEVICE_TABLE(acpi, intel_oc_wdt_match); + +static struct platform_driver intel_oc_wdt_platform_driver = { + .driver = { + .name = DRV_NAME, + .acpi_match_table = intel_oc_wdt_match, + }, + .probe = intel_oc_wdt_probe, +}; + +module_platform_driver(intel_oc_wdt_platform_driver); + +MODULE_AUTHOR("Diogo Ivo <diogo.ivo@siemens.com>"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Intel OC Watchdog driver");
Add a driver for the Intel Over-Clocking Watchdog found in Intel Platform Controller (PCH) chipsets. This watchdog is controlled via a simple single-register interface and would otherwise be standard except for the presence of a LOCK bit that can only be set once per power cycle, needing extra handling around it. Signed-off-by: Diogo Ivo <diogo.ivo@siemens.com> --- v1->v2: - Split v1 into two patches, adding the ACPI IDs in a separate patch - Initialize hearbeat module parameter to zero - Clarify wording around lock handling - Properly print resource with %pR when failing to obtain it - Enable compile testing and add dependency on HAS_IOPORT - Drop unneeded ACPI_PTR() and MODULE_ALIAS() --- --- drivers/watchdog/Kconfig | 11 ++ drivers/watchdog/Makefile | 1 + drivers/watchdog/intel_oc_wdt.c | 233 ++++++++++++++++++++++++++++++++++++++++ 3 files changed, 245 insertions(+)