Re: [PATCH v3 4/4] watchdog/pseries-wdt: initial support for H_WATCHDOG-based watchdog timers
Guenter Roeck writes: > On Mon, Jul 25, 2022 at 11:11:41AM -0500, Scott Cheloha wrote: >> On Wed, Jul 13, 2022 at 01:50:14PM -0700, Guenter Roeck wrote: >> > On 7/13/22 13:23, Scott Cheloha wrote: >> > > PAPR v2.12 defines a new hypercall, H_WATCHDOG. The hypercall permits >> > > guest control of one or more virtual watchdog timers. The timers have >> > > millisecond granularity. The guest is terminated when a timer >> > > expires. >> > > >> > > This patch adds a watchdog driver for these timers, "pseries-wdt". >> > > >> > > pseries_wdt_probe() currently assumes the existence of only one >> > > platform device and always assigns it watchdogNumber 1. If we ever >> > > expose more than one timer to userspace we will need to devise a way >> > > to assign a distinct watchdogNumber to each platform device at device >> > > registration time. >> > > >> > > Signed-off-by: Scott Cheloha >> > >> > Acked-by: Guenter Roeck >> >> Guenter, Michael, >> >> Which tree is taking this series? powerpc. It's been in next-test/next for about a week. It's in linux-next today. > The series includes non-watchdog changes, so my expectation was that some > other tree would take it. Yep, thanks for the ack. cheers
Re: [PATCH v3 4/4] watchdog/pseries-wdt: initial support for H_WATCHDOG-based watchdog timers
On Mon, Jul 25, 2022 at 11:11:41AM -0500, Scott Cheloha wrote: > On Wed, Jul 13, 2022 at 01:50:14PM -0700, Guenter Roeck wrote: > > On 7/13/22 13:23, Scott Cheloha wrote: > > > PAPR v2.12 defines a new hypercall, H_WATCHDOG. The hypercall permits > > > guest control of one or more virtual watchdog timers. The timers have > > > millisecond granularity. The guest is terminated when a timer > > > expires. > > > > > > This patch adds a watchdog driver for these timers, "pseries-wdt". > > > > > > pseries_wdt_probe() currently assumes the existence of only one > > > platform device and always assigns it watchdogNumber 1. If we ever > > > expose more than one timer to userspace we will need to devise a way > > > to assign a distinct watchdogNumber to each platform device at device > > > registration time. > > > > > > Signed-off-by: Scott Cheloha > > > > Acked-by: Guenter Roeck > > Guenter, Michael, > > Which tree is taking this series? > The series includes non-watchdog changes, so my expectation was that some other tree would take it. Guenter > watchdog-next or PPC development? > > -Scott
Re: [PATCH v3 4/4] watchdog/pseries-wdt: initial support for H_WATCHDOG-based watchdog timers
On Wed, Jul 13, 2022 at 01:50:14PM -0700, Guenter Roeck wrote: > On 7/13/22 13:23, Scott Cheloha wrote: > > PAPR v2.12 defines a new hypercall, H_WATCHDOG. The hypercall permits > > guest control of one or more virtual watchdog timers. The timers have > > millisecond granularity. The guest is terminated when a timer > > expires. > > > > This patch adds a watchdog driver for these timers, "pseries-wdt". > > > > pseries_wdt_probe() currently assumes the existence of only one > > platform device and always assigns it watchdogNumber 1. If we ever > > expose more than one timer to userspace we will need to devise a way > > to assign a distinct watchdogNumber to each platform device at device > > registration time. > > > > Signed-off-by: Scott Cheloha > > Acked-by: Guenter Roeck Guenter, Michael, Which tree is taking this series? watchdog-next or PPC development? -Scott
Re: [PATCH v3 4/4] watchdog/pseries-wdt: initial support for H_WATCHDOG-based watchdog timers
On 7/13/22 13:23, Scott Cheloha wrote: PAPR v2.12 defines a new hypercall, H_WATCHDOG. The hypercall permits guest control of one or more virtual watchdog timers. The timers have millisecond granularity. The guest is terminated when a timer expires. This patch adds a watchdog driver for these timers, "pseries-wdt". pseries_wdt_probe() currently assumes the existence of only one platform device and always assigns it watchdogNumber 1. If we ever expose more than one timer to userspace we will need to devise a way to assign a distinct watchdogNumber to each platform device at device registration time. Signed-off-by: Scott Cheloha Acked-by: Guenter Roeck --- .../watchdog/watchdog-parameters.rst | 12 + drivers/watchdog/Kconfig | 8 + drivers/watchdog/Makefile | 1 + drivers/watchdog/pseries-wdt.c| 239 ++ 4 files changed, 260 insertions(+) create mode 100644 drivers/watchdog/pseries-wdt.c diff --git a/Documentation/watchdog/watchdog-parameters.rst b/Documentation/watchdog/watchdog-parameters.rst index 223c99361a30..29153eed6689 100644 --- a/Documentation/watchdog/watchdog-parameters.rst +++ b/Documentation/watchdog/watchdog-parameters.rst @@ -425,6 +425,18 @@ pnx833x_wdt: - +pseries-wdt: +action: + Action taken when watchdog expires: 0 (power off), 1 (restart), + 2 (dump and restart). (default=1) +timeout: + Initial watchdog timeout in seconds. (default=60) +nowayout: + Watchdog cannot be stopped once started. + (default=kernel config parameter) + +- + rc32434_wdt: timeout: Watchdog timeout value, in seconds (default=20) diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 32fd37698932..a2429604a4ab 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -1962,6 +1962,14 @@ config MEN_A21_WDT # PPC64 Architecture +config PSERIES_WDT + tristate "POWER Architecture Platform Watchdog Timer" + depends on PPC_PSERIES + select WATCHDOG_CORE + help + Driver for virtual watchdog timers provided by PAPR + hypervisors (e.g. PowerVM, KVM). + config WATCHDOG_RTAS tristate "RTAS watchdog" depends on PPC_RTAS diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index c324e9d820e9..cdeb119e6e61 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -187,6 +187,7 @@ obj-$(CONFIG_BOOKE_WDT) += booke_wdt.o obj-$(CONFIG_MEN_A21_WDT) += mena21_wdt.o # PPC64 Architecture +obj-$(CONFIG_PSERIES_WDT) += pseries-wdt.o obj-$(CONFIG_WATCHDOG_RTAS) += wdrtas.o # S390 Architecture diff --git a/drivers/watchdog/pseries-wdt.c b/drivers/watchdog/pseries-wdt.c new file mode 100644 index ..7f53b5293409 --- /dev/null +++ b/drivers/watchdog/pseries-wdt.c @@ -0,0 +1,239 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2022 International Business Machines, Inc. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define DRV_NAME "pseries-wdt" + +/* + * H_WATCHDOG Input + * + * R4: "flags": + * + * Bits 48-55: "operation" + */ +#define PSERIES_WDTF_OP_START 0x100UL /* start timer */ +#define PSERIES_WDTF_OP_STOP 0x200UL /* stop timer */ +#define PSERIES_WDTF_OP_QUERY 0x300UL /* query timer capabilities */ + +/* + * Bits 56-63: "timeoutAction" (for "Start Watchdog" only) + */ +#define PSERIES_WDTF_ACTION_HARD_POWEROFF 0x1UL /* poweroff */ +#define PSERIES_WDTF_ACTION_HARD_RESTART 0x2UL /* restart */ +#define PSERIES_WDTF_ACTION_DUMP_RESTART 0x3UL /* dump + restart */ + +/* + * H_WATCHDOG Output + * + * R3: Return code + * + * H_SUCCESSThe operation completed. + * + * H_BUSY The hypervisor is too busy; retry the operation. + * + * H_PARAMETER The given "flags" are somehow invalid. Either the + * "operation" or "timeoutAction" is invalid, or a + * reserved bit is set. + * + * H_P2 The given "watchdogNumber" is zero or exceeds the + * supported maximum value. + * + * H_P3 The given "timeoutInMs" is below the supported + * minimum value. + * + * H_NOOP The given "watchdogNumber" is already stopped. + * + * H_HARDWARE The operation failed for ineffable reasons. + * + * H_FUNCTION The H_WATCHDOG hypercall is not supported by this + * hypervisor. + * + * R4: + * + * - For the "Query Watchdog Capabilities" operation, a 64-bit + * structure: + */ +#define PSERIES_WDTQ_MIN_TIMEOUT(cap) (((cap) >> 48) & 0x) +#define PSERIES_WDTQ_MAX_NUMBER(cap) (((cap) >> 32) & 0x) + +static const unsigned long
[PATCH v3 4/4] watchdog/pseries-wdt: initial support for H_WATCHDOG-based watchdog timers
PAPR v2.12 defines a new hypercall, H_WATCHDOG. The hypercall permits
guest control of one or more virtual watchdog timers. The timers have
millisecond granularity. The guest is terminated when a timer
expires.
This patch adds a watchdog driver for these timers, "pseries-wdt".
pseries_wdt_probe() currently assumes the existence of only one
platform device and always assigns it watchdogNumber 1. If we ever
expose more than one timer to userspace we will need to devise a way
to assign a distinct watchdogNumber to each platform device at device
registration time.
Signed-off-by: Scott Cheloha
---
.../watchdog/watchdog-parameters.rst | 12 +
drivers/watchdog/Kconfig | 8 +
drivers/watchdog/Makefile | 1 +
drivers/watchdog/pseries-wdt.c| 239 ++
4 files changed, 260 insertions(+)
create mode 100644 drivers/watchdog/pseries-wdt.c
diff --git a/Documentation/watchdog/watchdog-parameters.rst
b/Documentation/watchdog/watchdog-parameters.rst
index 223c99361a30..29153eed6689 100644
--- a/Documentation/watchdog/watchdog-parameters.rst
+++ b/Documentation/watchdog/watchdog-parameters.rst
@@ -425,6 +425,18 @@ pnx833x_wdt:
-
+pseries-wdt:
+action:
+ Action taken when watchdog expires: 0 (power off), 1 (restart),
+ 2 (dump and restart). (default=1)
+timeout:
+ Initial watchdog timeout in seconds. (default=60)
+nowayout:
+ Watchdog cannot be stopped once started.
+ (default=kernel config parameter)
+
+-
+
rc32434_wdt:
timeout:
Watchdog timeout value, in seconds (default=20)
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 32fd37698932..a2429604a4ab 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -1962,6 +1962,14 @@ config MEN_A21_WDT
# PPC64 Architecture
+config PSERIES_WDT
+ tristate "POWER Architecture Platform Watchdog Timer"
+ depends on PPC_PSERIES
+ select WATCHDOG_CORE
+ help
+ Driver for virtual watchdog timers provided by PAPR
+ hypervisors (e.g. PowerVM, KVM).
+
config WATCHDOG_RTAS
tristate "RTAS watchdog"
depends on PPC_RTAS
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index c324e9d820e9..cdeb119e6e61 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -187,6 +187,7 @@ obj-$(CONFIG_BOOKE_WDT) += booke_wdt.o
obj-$(CONFIG_MEN_A21_WDT) += mena21_wdt.o
# PPC64 Architecture
+obj-$(CONFIG_PSERIES_WDT) += pseries-wdt.o
obj-$(CONFIG_WATCHDOG_RTAS) += wdrtas.o
# S390 Architecture
diff --git a/drivers/watchdog/pseries-wdt.c b/drivers/watchdog/pseries-wdt.c
new file mode 100644
index ..7f53b5293409
--- /dev/null
+++ b/drivers/watchdog/pseries-wdt.c
@@ -0,0 +1,239 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2022 International Business Machines, Inc.
+ */
+
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+#define DRV_NAME "pseries-wdt"
+
+/*
+ * H_WATCHDOG Input
+ *
+ * R4: "flags":
+ *
+ * Bits 48-55: "operation"
+ */
+#define PSERIES_WDTF_OP_START 0x100UL /* start timer */
+#define PSERIES_WDTF_OP_STOP 0x200UL /* stop timer */
+#define PSERIES_WDTF_OP_QUERY 0x300UL /* query timer capabilities */
+
+/*
+ * Bits 56-63: "timeoutAction" (for "Start Watchdog" only)
+ */
+#define PSERIES_WDTF_ACTION_HARD_POWEROFF 0x1UL /* poweroff */
+#define PSERIES_WDTF_ACTION_HARD_RESTART 0x2UL /* restart */
+#define PSERIES_WDTF_ACTION_DUMP_RESTART 0x3UL /* dump + restart */
+
+/*
+ * H_WATCHDOG Output
+ *
+ * R3: Return code
+ *
+ * H_SUCCESSThe operation completed.
+ *
+ * H_BUSY The hypervisor is too busy; retry the operation.
+ *
+ * H_PARAMETER The given "flags" are somehow invalid. Either the
+ * "operation" or "timeoutAction" is invalid, or a
+ * reserved bit is set.
+ *
+ * H_P2 The given "watchdogNumber" is zero or exceeds the
+ * supported maximum value.
+ *
+ * H_P3 The given "timeoutInMs" is below the supported
+ * minimum value.
+ *
+ * H_NOOP The given "watchdogNumber" is already stopped.
+ *
+ * H_HARDWARE The operation failed for ineffable reasons.
+ *
+ * H_FUNCTION The H_WATCHDOG hypercall is not supported by this
+ * hypervisor.
+ *
+ * R4:
+ *
+ * - For the "Query Watchdog Capabilities" operation, a 64-bit
+ * structure:
+ */
+#define PSERIES_WDTQ_MIN_TIMEOUT(cap) (((cap) >> 48) & 0x)
+#define PSERIES_WDTQ_MAX_NUMBER(cap) (((cap) >> 32) & 0x)
+
+static const unsigned long pseries_wdt_action[] = {
+ [0] = PSERIES_WDTF_ACTION_HARD_POWEROFF,
+ [1] =
