All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH v1 1/4] powerpc/pseries: hvcall.h: add H_WATCHDOG opcode, H_NOOP return code
@ 2022-05-20 17:20 ` Scott Cheloha
  0 siblings, 0 replies; 12+ messages in thread
From: Scott Cheloha @ 2022-05-20 17:20 UTC (permalink / raw)
  To: linux-watchdog
  Cc: linux, tzungbi, brking, nathanl, aik, npiggin, vaishnavi, wvoigt,
	linuxppc-dev, Scott Cheloha

PAPR v2.12 defines a new hypercall, H_WATCHDOG.  The hypercall permits
guest control of one or more virtual watchdog timers.

Add the opcode for the H_WATCHDOG hypercall to hvcall.h.  While here,
add a definition for H_NOOP, a possible return code for H_WATCHDOG.

Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>
---
 arch/powerpc/include/asm/hvcall.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h
index d92a20a85395..4b4f69c35b4f 100644
--- a/arch/powerpc/include/asm/hvcall.h
+++ b/arch/powerpc/include/asm/hvcall.h
@@ -87,6 +87,7 @@
 #define H_P7		-60
 #define H_P8		-61
 #define H_P9		-62
+#define H_NOOP		-63
 #define H_TOO_BIG	-64
 #define H_UNSUPPORTED	-67
 #define H_OVERLAP	-68
@@ -324,7 +325,8 @@
 #define H_RPT_INVALIDATE	0x448
 #define H_SCM_FLUSH		0x44C
 #define H_GET_ENERGY_SCALE_INFO	0x450
-#define MAX_HCALL_OPCODE	H_GET_ENERGY_SCALE_INFO
+#define H_WATCHDOG		0x45C
+#define MAX_HCALL_OPCODE	H_WATCHDOG
 
 /* Scope args for H_SCM_UNBIND_ALL */
 #define H_UNBIND_SCOPE_ALL (0x1)
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH v1 1/4] powerpc/pseries: hvcall.h: add H_WATCHDOG opcode, H_NOOP return code
@ 2022-05-20 17:20 ` Scott Cheloha
  0 siblings, 0 replies; 12+ messages in thread
From: Scott Cheloha @ 2022-05-20 17:20 UTC (permalink / raw)
  To: linux-watchdog
  Cc: nathanl, wvoigt, aik, Scott Cheloha, vaishnavi, npiggin, tzungbi,
	brking, linuxppc-dev, linux

PAPR v2.12 defines a new hypercall, H_WATCHDOG.  The hypercall permits
guest control of one or more virtual watchdog timers.

Add the opcode for the H_WATCHDOG hypercall to hvcall.h.  While here,
add a definition for H_NOOP, a possible return code for H_WATCHDOG.

Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>
---
 arch/powerpc/include/asm/hvcall.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h
index d92a20a85395..4b4f69c35b4f 100644
--- a/arch/powerpc/include/asm/hvcall.h
+++ b/arch/powerpc/include/asm/hvcall.h
@@ -87,6 +87,7 @@
 #define H_P7		-60
 #define H_P8		-61
 #define H_P9		-62
+#define H_NOOP		-63
 #define H_TOO_BIG	-64
 #define H_UNSUPPORTED	-67
 #define H_OVERLAP	-68
@@ -324,7 +325,8 @@
 #define H_RPT_INVALIDATE	0x448
 #define H_SCM_FLUSH		0x44C
 #define H_GET_ENERGY_SCALE_INFO	0x450
-#define MAX_HCALL_OPCODE	H_GET_ENERGY_SCALE_INFO
+#define H_WATCHDOG		0x45C
+#define MAX_HCALL_OPCODE	H_WATCHDOG
 
 /* Scope args for H_SCM_UNBIND_ALL */
 #define H_UNBIND_SCOPE_ALL (0x1)
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH v1 2/4] powerpc/pseries: add FW_FEATURE_WATCHDOG flag
  2022-05-20 17:20 ` Scott Cheloha
@ 2022-05-20 17:20   ` Scott Cheloha
  -1 siblings, 0 replies; 12+ messages in thread
From: Scott Cheloha @ 2022-05-20 17:20 UTC (permalink / raw)
  To: linux-watchdog
  Cc: linux, tzungbi, brking, nathanl, aik, npiggin, vaishnavi, wvoigt,
	linuxppc-dev, Scott Cheloha

PAPR v2.12 specifies a new optional function set, "hcall-watchdog",
for the /rtas/ibm,hypertas-functions property.  The presence of this
function set indicates support for the H_WATCHDOG hypercall.

Check for this function set and, if present, set the new
FW_FEATURE_WATCHDOG flag.

Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>
---
 arch/powerpc/include/asm/firmware.h       | 3 ++-
 arch/powerpc/platforms/pseries/firmware.c | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/firmware.h b/arch/powerpc/include/asm/firmware.h
index 8dddd34b8ecf..398e0b5e485f 100644
--- a/arch/powerpc/include/asm/firmware.h
+++ b/arch/powerpc/include/asm/firmware.h
@@ -55,6 +55,7 @@
 #define FW_FEATURE_RPT_INVALIDATE ASM_CONST(0x0000010000000000)
 #define FW_FEATURE_FORM2_AFFINITY ASM_CONST(0x0000020000000000)
 #define FW_FEATURE_ENERGY_SCALE_INFO ASM_CONST(0x0000040000000000)
+#define FW_FEATURE_WATCHDOG	ASM_CONST(0x0000080000000000)
 
 #ifndef __ASSEMBLY__
 
@@ -76,7 +77,7 @@ enum {
 		FW_FEATURE_DRC_INFO | FW_FEATURE_BLOCK_REMOVE |
 		FW_FEATURE_PAPR_SCM | FW_FEATURE_ULTRAVISOR |
 		FW_FEATURE_RPT_INVALIDATE | FW_FEATURE_FORM2_AFFINITY |
-		FW_FEATURE_ENERGY_SCALE_INFO,
+		FW_FEATURE_ENERGY_SCALE_INFO | FW_FEATURE_WATCHDOG,
 	FW_FEATURE_PSERIES_ALWAYS = 0,
 	FW_FEATURE_POWERNV_POSSIBLE = FW_FEATURE_OPAL | FW_FEATURE_ULTRAVISOR,
 	FW_FEATURE_POWERNV_ALWAYS = 0,
diff --git a/arch/powerpc/platforms/pseries/firmware.c b/arch/powerpc/platforms/pseries/firmware.c
index 09c119b2f623..080108d129ed 100644
--- a/arch/powerpc/platforms/pseries/firmware.c
+++ b/arch/powerpc/platforms/pseries/firmware.c
@@ -67,6 +67,7 @@ hypertas_fw_features_table[] = {
 	{FW_FEATURE_PAPR_SCM,		"hcall-scm"},
 	{FW_FEATURE_RPT_INVALIDATE,	"hcall-rpt-invalidate"},
 	{FW_FEATURE_ENERGY_SCALE_INFO,	"hcall-energy-scale-info"},
+	{FW_FEATURE_WATCHDOG,		"hcall-watchdog"},
 };
 
 /* Build up the firmware features bitmask using the contents of
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH v1 2/4] powerpc/pseries: add FW_FEATURE_WATCHDOG flag
@ 2022-05-20 17:20   ` Scott Cheloha
  0 siblings, 0 replies; 12+ messages in thread
From: Scott Cheloha @ 2022-05-20 17:20 UTC (permalink / raw)
  To: linux-watchdog
  Cc: nathanl, wvoigt, aik, Scott Cheloha, vaishnavi, npiggin, tzungbi,
	brking, linuxppc-dev, linux

PAPR v2.12 specifies a new optional function set, "hcall-watchdog",
for the /rtas/ibm,hypertas-functions property.  The presence of this
function set indicates support for the H_WATCHDOG hypercall.

Check for this function set and, if present, set the new
FW_FEATURE_WATCHDOG flag.

Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>
---
 arch/powerpc/include/asm/firmware.h       | 3 ++-
 arch/powerpc/platforms/pseries/firmware.c | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/firmware.h b/arch/powerpc/include/asm/firmware.h
index 8dddd34b8ecf..398e0b5e485f 100644
--- a/arch/powerpc/include/asm/firmware.h
+++ b/arch/powerpc/include/asm/firmware.h
@@ -55,6 +55,7 @@
 #define FW_FEATURE_RPT_INVALIDATE ASM_CONST(0x0000010000000000)
 #define FW_FEATURE_FORM2_AFFINITY ASM_CONST(0x0000020000000000)
 #define FW_FEATURE_ENERGY_SCALE_INFO ASM_CONST(0x0000040000000000)
+#define FW_FEATURE_WATCHDOG	ASM_CONST(0x0000080000000000)
 
 #ifndef __ASSEMBLY__
 
@@ -76,7 +77,7 @@ enum {
 		FW_FEATURE_DRC_INFO | FW_FEATURE_BLOCK_REMOVE |
 		FW_FEATURE_PAPR_SCM | FW_FEATURE_ULTRAVISOR |
 		FW_FEATURE_RPT_INVALIDATE | FW_FEATURE_FORM2_AFFINITY |
-		FW_FEATURE_ENERGY_SCALE_INFO,
+		FW_FEATURE_ENERGY_SCALE_INFO | FW_FEATURE_WATCHDOG,
 	FW_FEATURE_PSERIES_ALWAYS = 0,
 	FW_FEATURE_POWERNV_POSSIBLE = FW_FEATURE_OPAL | FW_FEATURE_ULTRAVISOR,
 	FW_FEATURE_POWERNV_ALWAYS = 0,
diff --git a/arch/powerpc/platforms/pseries/firmware.c b/arch/powerpc/platforms/pseries/firmware.c
index 09c119b2f623..080108d129ed 100644
--- a/arch/powerpc/platforms/pseries/firmware.c
+++ b/arch/powerpc/platforms/pseries/firmware.c
@@ -67,6 +67,7 @@ hypertas_fw_features_table[] = {
 	{FW_FEATURE_PAPR_SCM,		"hcall-scm"},
 	{FW_FEATURE_RPT_INVALIDATE,	"hcall-rpt-invalidate"},
 	{FW_FEATURE_ENERGY_SCALE_INFO,	"hcall-energy-scale-info"},
+	{FW_FEATURE_WATCHDOG,		"hcall-watchdog"},
 };
 
 /* Build up the firmware features bitmask using the contents of
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH v1 3/4] powerpc/pseries: register pseries-wdt device with platform bus
  2022-05-20 17:20 ` Scott Cheloha
@ 2022-05-20 17:20   ` Scott Cheloha
  -1 siblings, 0 replies; 12+ messages in thread
From: Scott Cheloha @ 2022-05-20 17:20 UTC (permalink / raw)
  To: linux-watchdog
  Cc: linux, tzungbi, brking, nathanl, aik, npiggin, vaishnavi, wvoigt,
	linuxppc-dev, Scott Cheloha

PAPR v2.12 defines a new hypercall, H_WATCHDOG.  The hypercall permits
guest control of one or more virtual watchdog timers.

These timers do not conform to PowerPC device conventions.  They are
not affixed to any extant bus, nor do they have full representation in
the device tree.

As a workaround we represent them as platform devices.

This patch registers a single platform device, "pseries-wdt", with the
platform bus if the FW_FEATURE_WATCHDOG flag is set.

A driver for this device, "pseries-wdt", will be introduced in a
subsequent patch.

Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>
---
 arch/powerpc/platforms/pseries/setup.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 955ff8aa1644..6e8b67ea2a33 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -14,6 +14,7 @@
 
 #include <linux/cpu.h>
 #include <linux/errno.h>
+#include <linux/platform_device.h>
 #include <linux/sched.h>
 #include <linux/kernel.h>
 #include <linux/mm.h>
@@ -169,6 +170,22 @@ static void __init fwnmi_init(void)
 #endif
 }
 
+/*
+ * Affix a device for the first timer to the platform bus if
+ * we have firmware support for the H_WATCHDOG hypercall.
+ */
+static struct platform_device *pseries_wdt_pdev;
+
+static __init int pseries_wdt_init(void)
+{
+	if (!firmware_has_feature(FW_FEATURE_WATCHDOG))
+		return 0;
+	pseries_wdt_pdev = platform_device_register_simple("pseries-wdt",
+							   0, NULL, 0);
+	return 0;
+}
+machine_subsys_initcall(pseries, pseries_wdt_init);
+
 static void pseries_8259_cascade(struct irq_desc *desc)
 {
 	struct irq_chip *chip = irq_desc_get_chip(desc);
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH v1 3/4] powerpc/pseries: register pseries-wdt device with platform bus
@ 2022-05-20 17:20   ` Scott Cheloha
  0 siblings, 0 replies; 12+ messages in thread
From: Scott Cheloha @ 2022-05-20 17:20 UTC (permalink / raw)
  To: linux-watchdog
  Cc: nathanl, wvoigt, aik, Scott Cheloha, vaishnavi, npiggin, tzungbi,
	brking, linuxppc-dev, linux

PAPR v2.12 defines a new hypercall, H_WATCHDOG.  The hypercall permits
guest control of one or more virtual watchdog timers.

These timers do not conform to PowerPC device conventions.  They are
not affixed to any extant bus, nor do they have full representation in
the device tree.

As a workaround we represent them as platform devices.

This patch registers a single platform device, "pseries-wdt", with the
platform bus if the FW_FEATURE_WATCHDOG flag is set.

A driver for this device, "pseries-wdt", will be introduced in a
subsequent patch.

Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>
---
 arch/powerpc/platforms/pseries/setup.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 955ff8aa1644..6e8b67ea2a33 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -14,6 +14,7 @@
 
 #include <linux/cpu.h>
 #include <linux/errno.h>
+#include <linux/platform_device.h>
 #include <linux/sched.h>
 #include <linux/kernel.h>
 #include <linux/mm.h>
@@ -169,6 +170,22 @@ static void __init fwnmi_init(void)
 #endif
 }
 
+/*
+ * Affix a device for the first timer to the platform bus if
+ * we have firmware support for the H_WATCHDOG hypercall.
+ */
+static struct platform_device *pseries_wdt_pdev;
+
+static __init int pseries_wdt_init(void)
+{
+	if (!firmware_has_feature(FW_FEATURE_WATCHDOG))
+		return 0;
+	pseries_wdt_pdev = platform_device_register_simple("pseries-wdt",
+							   0, NULL, 0);
+	return 0;
+}
+machine_subsys_initcall(pseries, pseries_wdt_init);
+
 static void pseries_8259_cascade(struct irq_desc *desc)
 {
 	struct irq_chip *chip = irq_desc_get_chip(desc);
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH v1 4/4] watchdog/pseries-wdt: initial support for PAPR H_WATCHDOG timers
  2022-05-20 17:20 ` Scott Cheloha
@ 2022-05-20 17:20   ` Scott Cheloha
  -1 siblings, 0 replies; 12+ messages in thread
From: Scott Cheloha @ 2022-05-20 17:20 UTC (permalink / raw)
  To: linux-watchdog
  Cc: linux, tzungbi, brking, nathanl, aik, npiggin, vaishnavi, wvoigt,
	linuxppc-dev, Scott Cheloha

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 <cheloha@linux.ibm.com>
---
 .../watchdog/watchdog-parameters.rst          |  12 +
 drivers/watchdog/Kconfig                      |   8 +
 drivers/watchdog/Makefile                     |   1 +
 drivers/watchdog/pseries-wdt.c                | 337 ++++++++++++++++++
 4 files changed, 358 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..4ffe725e796c 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: 1 (power off), 2 (restart),
+	3 (dump and restart). (default=2)
+    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 c4e82a8d863f..06b412603f3e 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -1932,6 +1932,14 @@ 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 f7da867e8782..f35660409f17 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -184,6 +184,7 @@ 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 000000000000..f41bc4d3b7a2
--- /dev/null
+++ b/drivers/watchdog/pseries-wdt.c
@@ -0,0 +1,337 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2022 International Business Machines, Inc.
+ */
+
+#include <linux/bitops.h>
+#include <linux/kernel.h>
+#include <linux/limits.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/platform_device.h>
+#include <linux/watchdog.h>
+
+#define DRV_NAME "pseries-wdt"
+
+/*
+ * The PAPR's MSB->LSB bit ordering is 0->63.  These macros simplify
+ * defining bitfields as described in the PAPR without needing to
+ * transpose values to the more C-like 63->0 ordering.
+ */
+#define SETFIELD(_v, _b, _e)	\
+	(((unsigned long)(_v) << PPC_BITLSHIFT(_e)) & PPC_BITMASK((_b), (_e)))
+#define GETFIELD(_v, _b, _e)	\
+	(((unsigned long)(_v) & PPC_BITMASK((_b), (_e))) >> PPC_BITLSHIFT(_e))
+
+/*
+ * H_WATCHDOG Hypercall Input
+ *
+ * R4: "flags":
+ *
+ *     A 64-bit value structured as follows:
+ *
+ *         Bits 0-46: Reserved (must be zero).
+ */
+#define PSERIES_WDTF_RESERVED	PPC_BITMASK(0, 46)
+
+/*
+ *         Bit 47: "leaveOtherWatchdogsRunningOnTimeout"
+ *
+ *             0  Stop outstanding watchdogs on timeout.
+ *             1  Leave outstanding watchdogs running on timeout.
+ */
+#define PSERIES_WDTF_LEAVE_OTHER	PPC_BIT(47)
+
+/*
+ *         Bits 48-55: "operation"
+ *
+ *             0x01  Start Watchdog
+ *             0x02  Stop Watchdog
+ *             0x03  Query Watchdog Capabilities
+ *             0x04  Query Watchdog LPM Requirement
+ */
+#define PSERIES_WDTF_OP(op)		SETFIELD((op), 48, 55)
+#define PSERIES_WDTF_OP_START		PSERIES_WDTF_OP(0x1)
+#define PSERIES_WDTF_OP_STOP		PSERIES_WDTF_OP(0x2)
+#define PSERIES_WDTF_OP_QUERY		PSERIES_WDTF_OP(0x3)
+#define PSERIES_WDTF_OP_QUERY_LPM	PSERIES_WDTF_OP(0x4)
+
+/*
+ *         Bits 56-63: "timeoutAction"
+ *
+ *             0x01  Hard poweroff
+ *             0x02  Hard restart
+ *             0x03  Dump restart
+ */
+#define PSERIES_WDTF_ACTION(ac)			SETFIELD(ac, 56, 63)
+#define PSERIES_WDTF_ACTION_HARD_POWEROFF	PSERIES_WDTF_ACTION(0x1)
+#define PSERIES_WDTF_ACTION_HARD_RESTART	PSERIES_WDTF_ACTION(0x2)
+#define PSERIES_WDTF_ACTION_DUMP_RESTART	PSERIES_WDTF_ACTION(0x3)
+
+/*
+ * R5: "watchdogNumber":
+ *
+ *     The target watchdog.  Watchdog numbers are 1-based.  The
+ *     maximum supported watchdog number may be obtained via the
+ *     "Query Watchdog Capabilities" operation.
+ *
+ *     This input is ignored for the "Query Watchdog Capabilities"
+ *     operation.
+ *
+ * R6: "timeoutInMs":
+ *
+ *     The timeout in milliseconds.  The minimum supported timeout may
+ *     be obtained via the "Query Watchdog Capabilities" operation.
+ *
+ *     This input is ignored for the "Stop Watchdog", "Query Watchdog
+ *     Capabilities", and "Query Watchdog LPM Requirement" operations.
+ */
+
+/*
+ * H_WATCHDOG Hypercall Output
+ *
+ * R3: Return code
+ *
+ *     H_SUCCESS    The 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
+ *   value structured as follows:
+ *
+ *       Bits  0-15: The minimum supported timeout in milliseconds.
+ *       Bits 16-31: The number of watchdogs supported.
+ *       Bits 32-63: Reserved.
+ */
+#define PSERIES_WDTQ_MIN_TIMEOUT(cap)	GETFIELD((cap), 0, 15)
+#define PSERIES_WDTQ_MAX_NUMBER(cap)	GETFIELD((cap), 16, 31)
+#define PSERIES_WDTQ_RESERVED		PPC_BITMASK(32, 63)
+
+/*
+ * - For the "Query Watchdog LPM Requirement" operation:
+ *
+ *       1  The given "watchdogNumber" must be stopped prior to
+ *          suspending.
+ *
+ *       2  The given "watchdogNumber" does not have to be stopped
+ *          prior to suspending.
+ */
+#define PSERIES_WDTQL_MUST_STOP		1
+#define PSERIES_WDTQL_NEED_NOT_STOP	2
+
+static unsigned long action = PSERIES_WDTF_ACTION_HARD_RESTART;
+
+static int action_get(char *buf, const struct kernel_param *kp)
+{
+	int val;
+
+	switch (action) {
+	case PSERIES_WDTF_ACTION_HARD_POWEROFF:
+		val = 1;
+		break;
+	case PSERIES_WDTF_ACTION_HARD_RESTART:
+		val = 2;
+		break;
+	case PSERIES_WDTF_ACTION_DUMP_RESTART:
+		val = 3;
+		break;
+	default:
+		return -EINVAL;
+	}
+	return sprintf(buf, "%d\n", val);
+}
+
+static int action_set(const char *val, const struct kernel_param *kp)
+{
+	int choice;
+
+	if (kstrtoint(val, 10, &choice))
+		return -EINVAL;
+	switch (choice) {
+	case 1:
+		action = PSERIES_WDTF_ACTION_HARD_POWEROFF;
+		return 0;
+	case 2:
+		action = PSERIES_WDTF_ACTION_HARD_RESTART;
+		return 0;
+	case 3:
+		action = PSERIES_WDTF_ACTION_DUMP_RESTART;
+		return 0;
+	}
+	return -EINVAL;
+}
+
+static const struct kernel_param_ops action_ops = {
+	.get = action_get,
+	.set = action_set,
+};
+module_param_cb(action, &action_ops, NULL, 0444);
+MODULE_PARM_DESC(action, "Action taken when watchdog expires (default=2)");
+
+static bool nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, bool, 0444);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
+		 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+#define WATCHDOG_TIMEOUT 60
+static unsigned int timeout = WATCHDOG_TIMEOUT;
+module_param(timeout, uint, 0444);
+MODULE_PARM_DESC(timeout, "Initial watchdog timeout in seconds (default="
+		 __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
+
+struct pseries_wdt {
+	struct watchdog_device wd;
+	unsigned long num;		/* Watchdog numbers are 1-based */
+};
+
+static int pseries_wdt_start(struct watchdog_device *wdd)
+{
+	struct device *dev = wdd->parent;
+	struct pseries_wdt *pw = watchdog_get_drvdata(wdd);
+	unsigned long flags, msecs;
+	long rc;
+
+	flags = action | PSERIES_WDTF_OP_START;
+	msecs = wdd->timeout * 1000UL;
+	rc = plpar_hcall_norets(H_WATCHDOG, flags, pw->num, msecs);
+	if (rc != H_SUCCESS) {
+		dev_crit(dev, "H_WATCHDOG: %ld: failed to start timer %lu",
+			 rc, pw->num);
+		return -EIO;
+	}
+	return 0;
+}
+
+static int pseries_wdt_stop(struct watchdog_device *wdd)
+{
+	struct device *dev = wdd->parent;
+	struct pseries_wdt *pw = watchdog_get_drvdata(wdd);
+	long rc;
+
+	rc = plpar_hcall_norets(H_WATCHDOG, PSERIES_WDTF_OP_STOP, pw->num);
+	if (rc != H_SUCCESS && rc != H_NOOP) {
+		dev_crit(dev, "H_WATCHDOG: %ld: failed to stop timer %lu",
+			 rc, pw->num);
+		return -EIO;
+	}
+	return 0;
+}
+
+static struct watchdog_info pseries_wdt_info = {
+	.identity = DRV_NAME,
+	.options = WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT
+	    | WDIOF_PRETIMEOUT,
+};
+
+static const struct watchdog_ops pseries_wdt_ops = {
+	.owner = THIS_MODULE,
+	.start = pseries_wdt_start,
+	.stop = pseries_wdt_stop,
+};
+
+static int pseries_wdt_probe(struct platform_device *pdev)
+{
+	unsigned long ret[PLPAR_HCALL_BUFSIZE] = { 0 };
+	unsigned long cap, min_timeout_ms;
+	long rc;
+	struct pseries_wdt *pw;
+	int err;
+
+	rc = plpar_hcall(H_WATCHDOG, ret, PSERIES_WDTF_OP_QUERY);
+	if (rc != H_SUCCESS)
+		return rc == H_FUNCTION ? -ENODEV : -EIO;
+	cap = ret[0];
+
+	pw = devm_kzalloc(&pdev->dev, sizeof(*pw), GFP_KERNEL);
+	if (!pw)
+		return -ENOMEM;
+
+	/*
+	 * Assume watchdogNumber 1 for now.  If we ever support
+	 * multiple timers we will need to devise a way to choose a
+	 * distinct watchdogNumber for each platform device at device
+	 * registration time.
+	 */
+	pw->num = 1;
+
+	pw->wd.parent = &pdev->dev;
+	pw->wd.info = &pseries_wdt_info;
+	pw->wd.ops = &pseries_wdt_ops;
+	min_timeout_ms = PSERIES_WDTQ_MIN_TIMEOUT(cap);
+	pw->wd.min_timeout = roundup(min_timeout_ms, 1000) / 1000;
+	pw->wd.max_timeout = UINT_MAX;
+	watchdog_init_timeout(&pw->wd, timeout, NULL);
+	watchdog_set_nowayout(&pw->wd, nowayout);
+	watchdog_stop_on_reboot(&pw->wd);
+	watchdog_stop_on_unregister(&pw->wd);
+	watchdog_set_drvdata(&pw->wd, pw);
+
+	err = devm_watchdog_register_device(&pdev->dev, &pw->wd);
+	if (err)
+		return err;
+
+	platform_set_drvdata(pdev, &pw->wd);
+
+	return 0;
+}
+
+static int pseries_wdt_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	struct watchdog_device *wd = platform_get_drvdata(pdev);
+
+	if (watchdog_active(wd))
+		return pseries_wdt_stop(wd);
+	return 0;
+}
+
+static int pseries_wdt_resume(struct platform_device *pdev)
+{
+	struct watchdog_device *wd = platform_get_drvdata(pdev);
+
+	if (watchdog_active(wd))
+		return pseries_wdt_start(wd);
+	return 0;
+}
+
+static const struct platform_device_id pseries_wdt_id[] = {
+	{ .name = "pseries-wdt" },
+	{}
+};
+MODULE_DEVICE_TABLE(platform, pseries_wdt_id);
+
+static struct platform_driver pseries_wdt_driver = {
+	.driver = {
+		.name = DRV_NAME,
+		.owner = THIS_MODULE,
+	},
+	.id_table = pseries_wdt_id,
+	.probe = pseries_wdt_probe,
+	.resume = pseries_wdt_resume,
+	.suspend = pseries_wdt_suspend,
+};
+module_platform_driver(pseries_wdt_driver);
+
+MODULE_AUTHOR("Alexey Kardashevskiy <aik@ozlabs.ru>");
+MODULE_AUTHOR("Scott Cheloha <cheloha@linux.ibm.com>");
+MODULE_DESCRIPTION("POWER Architecture Platform Watchdog Driver");
+MODULE_LICENSE("GPL");
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH v1 4/4] watchdog/pseries-wdt: initial support for PAPR H_WATCHDOG timers
@ 2022-05-20 17:20   ` Scott Cheloha
  0 siblings, 0 replies; 12+ messages in thread
From: Scott Cheloha @ 2022-05-20 17:20 UTC (permalink / raw)
  To: linux-watchdog
  Cc: nathanl, wvoigt, aik, Scott Cheloha, vaishnavi, npiggin, tzungbi,
	brking, linuxppc-dev, linux

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 <cheloha@linux.ibm.com>
---
 .../watchdog/watchdog-parameters.rst          |  12 +
 drivers/watchdog/Kconfig                      |   8 +
 drivers/watchdog/Makefile                     |   1 +
 drivers/watchdog/pseries-wdt.c                | 337 ++++++++++++++++++
 4 files changed, 358 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..4ffe725e796c 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: 1 (power off), 2 (restart),
+	3 (dump and restart). (default=2)
+    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 c4e82a8d863f..06b412603f3e 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -1932,6 +1932,14 @@ 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 f7da867e8782..f35660409f17 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -184,6 +184,7 @@ 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 000000000000..f41bc4d3b7a2
--- /dev/null
+++ b/drivers/watchdog/pseries-wdt.c
@@ -0,0 +1,337 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2022 International Business Machines, Inc.
+ */
+
+#include <linux/bitops.h>
+#include <linux/kernel.h>
+#include <linux/limits.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/platform_device.h>
+#include <linux/watchdog.h>
+
+#define DRV_NAME "pseries-wdt"
+
+/*
+ * The PAPR's MSB->LSB bit ordering is 0->63.  These macros simplify
+ * defining bitfields as described in the PAPR without needing to
+ * transpose values to the more C-like 63->0 ordering.
+ */
+#define SETFIELD(_v, _b, _e)	\
+	(((unsigned long)(_v) << PPC_BITLSHIFT(_e)) & PPC_BITMASK((_b), (_e)))
+#define GETFIELD(_v, _b, _e)	\
+	(((unsigned long)(_v) & PPC_BITMASK((_b), (_e))) >> PPC_BITLSHIFT(_e))
+
+/*
+ * H_WATCHDOG Hypercall Input
+ *
+ * R4: "flags":
+ *
+ *     A 64-bit value structured as follows:
+ *
+ *         Bits 0-46: Reserved (must be zero).
+ */
+#define PSERIES_WDTF_RESERVED	PPC_BITMASK(0, 46)
+
+/*
+ *         Bit 47: "leaveOtherWatchdogsRunningOnTimeout"
+ *
+ *             0  Stop outstanding watchdogs on timeout.
+ *             1  Leave outstanding watchdogs running on timeout.
+ */
+#define PSERIES_WDTF_LEAVE_OTHER	PPC_BIT(47)
+
+/*
+ *         Bits 48-55: "operation"
+ *
+ *             0x01  Start Watchdog
+ *             0x02  Stop Watchdog
+ *             0x03  Query Watchdog Capabilities
+ *             0x04  Query Watchdog LPM Requirement
+ */
+#define PSERIES_WDTF_OP(op)		SETFIELD((op), 48, 55)
+#define PSERIES_WDTF_OP_START		PSERIES_WDTF_OP(0x1)
+#define PSERIES_WDTF_OP_STOP		PSERIES_WDTF_OP(0x2)
+#define PSERIES_WDTF_OP_QUERY		PSERIES_WDTF_OP(0x3)
+#define PSERIES_WDTF_OP_QUERY_LPM	PSERIES_WDTF_OP(0x4)
+
+/*
+ *         Bits 56-63: "timeoutAction"
+ *
+ *             0x01  Hard poweroff
+ *             0x02  Hard restart
+ *             0x03  Dump restart
+ */
+#define PSERIES_WDTF_ACTION(ac)			SETFIELD(ac, 56, 63)
+#define PSERIES_WDTF_ACTION_HARD_POWEROFF	PSERIES_WDTF_ACTION(0x1)
+#define PSERIES_WDTF_ACTION_HARD_RESTART	PSERIES_WDTF_ACTION(0x2)
+#define PSERIES_WDTF_ACTION_DUMP_RESTART	PSERIES_WDTF_ACTION(0x3)
+
+/*
+ * R5: "watchdogNumber":
+ *
+ *     The target watchdog.  Watchdog numbers are 1-based.  The
+ *     maximum supported watchdog number may be obtained via the
+ *     "Query Watchdog Capabilities" operation.
+ *
+ *     This input is ignored for the "Query Watchdog Capabilities"
+ *     operation.
+ *
+ * R6: "timeoutInMs":
+ *
+ *     The timeout in milliseconds.  The minimum supported timeout may
+ *     be obtained via the "Query Watchdog Capabilities" operation.
+ *
+ *     This input is ignored for the "Stop Watchdog", "Query Watchdog
+ *     Capabilities", and "Query Watchdog LPM Requirement" operations.
+ */
+
+/*
+ * H_WATCHDOG Hypercall Output
+ *
+ * R3: Return code
+ *
+ *     H_SUCCESS    The 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
+ *   value structured as follows:
+ *
+ *       Bits  0-15: The minimum supported timeout in milliseconds.
+ *       Bits 16-31: The number of watchdogs supported.
+ *       Bits 32-63: Reserved.
+ */
+#define PSERIES_WDTQ_MIN_TIMEOUT(cap)	GETFIELD((cap), 0, 15)
+#define PSERIES_WDTQ_MAX_NUMBER(cap)	GETFIELD((cap), 16, 31)
+#define PSERIES_WDTQ_RESERVED		PPC_BITMASK(32, 63)
+
+/*
+ * - For the "Query Watchdog LPM Requirement" operation:
+ *
+ *       1  The given "watchdogNumber" must be stopped prior to
+ *          suspending.
+ *
+ *       2  The given "watchdogNumber" does not have to be stopped
+ *          prior to suspending.
+ */
+#define PSERIES_WDTQL_MUST_STOP		1
+#define PSERIES_WDTQL_NEED_NOT_STOP	2
+
+static unsigned long action = PSERIES_WDTF_ACTION_HARD_RESTART;
+
+static int action_get(char *buf, const struct kernel_param *kp)
+{
+	int val;
+
+	switch (action) {
+	case PSERIES_WDTF_ACTION_HARD_POWEROFF:
+		val = 1;
+		break;
+	case PSERIES_WDTF_ACTION_HARD_RESTART:
+		val = 2;
+		break;
+	case PSERIES_WDTF_ACTION_DUMP_RESTART:
+		val = 3;
+		break;
+	default:
+		return -EINVAL;
+	}
+	return sprintf(buf, "%d\n", val);
+}
+
+static int action_set(const char *val, const struct kernel_param *kp)
+{
+	int choice;
+
+	if (kstrtoint(val, 10, &choice))
+		return -EINVAL;
+	switch (choice) {
+	case 1:
+		action = PSERIES_WDTF_ACTION_HARD_POWEROFF;
+		return 0;
+	case 2:
+		action = PSERIES_WDTF_ACTION_HARD_RESTART;
+		return 0;
+	case 3:
+		action = PSERIES_WDTF_ACTION_DUMP_RESTART;
+		return 0;
+	}
+	return -EINVAL;
+}
+
+static const struct kernel_param_ops action_ops = {
+	.get = action_get,
+	.set = action_set,
+};
+module_param_cb(action, &action_ops, NULL, 0444);
+MODULE_PARM_DESC(action, "Action taken when watchdog expires (default=2)");
+
+static bool nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, bool, 0444);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
+		 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+#define WATCHDOG_TIMEOUT 60
+static unsigned int timeout = WATCHDOG_TIMEOUT;
+module_param(timeout, uint, 0444);
+MODULE_PARM_DESC(timeout, "Initial watchdog timeout in seconds (default="
+		 __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
+
+struct pseries_wdt {
+	struct watchdog_device wd;
+	unsigned long num;		/* Watchdog numbers are 1-based */
+};
+
+static int pseries_wdt_start(struct watchdog_device *wdd)
+{
+	struct device *dev = wdd->parent;
+	struct pseries_wdt *pw = watchdog_get_drvdata(wdd);
+	unsigned long flags, msecs;
+	long rc;
+
+	flags = action | PSERIES_WDTF_OP_START;
+	msecs = wdd->timeout * 1000UL;
+	rc = plpar_hcall_norets(H_WATCHDOG, flags, pw->num, msecs);
+	if (rc != H_SUCCESS) {
+		dev_crit(dev, "H_WATCHDOG: %ld: failed to start timer %lu",
+			 rc, pw->num);
+		return -EIO;
+	}
+	return 0;
+}
+
+static int pseries_wdt_stop(struct watchdog_device *wdd)
+{
+	struct device *dev = wdd->parent;
+	struct pseries_wdt *pw = watchdog_get_drvdata(wdd);
+	long rc;
+
+	rc = plpar_hcall_norets(H_WATCHDOG, PSERIES_WDTF_OP_STOP, pw->num);
+	if (rc != H_SUCCESS && rc != H_NOOP) {
+		dev_crit(dev, "H_WATCHDOG: %ld: failed to stop timer %lu",
+			 rc, pw->num);
+		return -EIO;
+	}
+	return 0;
+}
+
+static struct watchdog_info pseries_wdt_info = {
+	.identity = DRV_NAME,
+	.options = WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT
+	    | WDIOF_PRETIMEOUT,
+};
+
+static const struct watchdog_ops pseries_wdt_ops = {
+	.owner = THIS_MODULE,
+	.start = pseries_wdt_start,
+	.stop = pseries_wdt_stop,
+};
+
+static int pseries_wdt_probe(struct platform_device *pdev)
+{
+	unsigned long ret[PLPAR_HCALL_BUFSIZE] = { 0 };
+	unsigned long cap, min_timeout_ms;
+	long rc;
+	struct pseries_wdt *pw;
+	int err;
+
+	rc = plpar_hcall(H_WATCHDOG, ret, PSERIES_WDTF_OP_QUERY);
+	if (rc != H_SUCCESS)
+		return rc == H_FUNCTION ? -ENODEV : -EIO;
+	cap = ret[0];
+
+	pw = devm_kzalloc(&pdev->dev, sizeof(*pw), GFP_KERNEL);
+	if (!pw)
+		return -ENOMEM;
+
+	/*
+	 * Assume watchdogNumber 1 for now.  If we ever support
+	 * multiple timers we will need to devise a way to choose a
+	 * distinct watchdogNumber for each platform device at device
+	 * registration time.
+	 */
+	pw->num = 1;
+
+	pw->wd.parent = &pdev->dev;
+	pw->wd.info = &pseries_wdt_info;
+	pw->wd.ops = &pseries_wdt_ops;
+	min_timeout_ms = PSERIES_WDTQ_MIN_TIMEOUT(cap);
+	pw->wd.min_timeout = roundup(min_timeout_ms, 1000) / 1000;
+	pw->wd.max_timeout = UINT_MAX;
+	watchdog_init_timeout(&pw->wd, timeout, NULL);
+	watchdog_set_nowayout(&pw->wd, nowayout);
+	watchdog_stop_on_reboot(&pw->wd);
+	watchdog_stop_on_unregister(&pw->wd);
+	watchdog_set_drvdata(&pw->wd, pw);
+
+	err = devm_watchdog_register_device(&pdev->dev, &pw->wd);
+	if (err)
+		return err;
+
+	platform_set_drvdata(pdev, &pw->wd);
+
+	return 0;
+}
+
+static int pseries_wdt_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	struct watchdog_device *wd = platform_get_drvdata(pdev);
+
+	if (watchdog_active(wd))
+		return pseries_wdt_stop(wd);
+	return 0;
+}
+
+static int pseries_wdt_resume(struct platform_device *pdev)
+{
+	struct watchdog_device *wd = platform_get_drvdata(pdev);
+
+	if (watchdog_active(wd))
+		return pseries_wdt_start(wd);
+	return 0;
+}
+
+static const struct platform_device_id pseries_wdt_id[] = {
+	{ .name = "pseries-wdt" },
+	{}
+};
+MODULE_DEVICE_TABLE(platform, pseries_wdt_id);
+
+static struct platform_driver pseries_wdt_driver = {
+	.driver = {
+		.name = DRV_NAME,
+		.owner = THIS_MODULE,
+	},
+	.id_table = pseries_wdt_id,
+	.probe = pseries_wdt_probe,
+	.resume = pseries_wdt_resume,
+	.suspend = pseries_wdt_suspend,
+};
+module_platform_driver(pseries_wdt_driver);
+
+MODULE_AUTHOR("Alexey Kardashevskiy <aik@ozlabs.ru>");
+MODULE_AUTHOR("Scott Cheloha <cheloha@linux.ibm.com>");
+MODULE_DESCRIPTION("POWER Architecture Platform Watchdog Driver");
+MODULE_LICENSE("GPL");
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* Re: [PATCH v1 1/4] powerpc/pseries: hvcall.h: add H_WATCHDOG opcode, H_NOOP return code
  2022-05-20 17:20 ` Scott Cheloha
@ 2022-05-20 17:44   ` Guenter Roeck
  -1 siblings, 0 replies; 12+ messages in thread
From: Guenter Roeck @ 2022-05-20 17:44 UTC (permalink / raw)
  To: Scott Cheloha, linux-watchdog
  Cc: tzungbi, brking, nathanl, aik, npiggin, vaishnavi, wvoigt, linuxppc-dev

On 5/20/22 10:20, Scott Cheloha wrote:
> PAPR v2.12 defines a new hypercall, H_WATCHDOG.  The hypercall permits
> guest control of one or more virtual watchdog timers.
> 
> Add the opcode for the H_WATCHDOG hypercall to hvcall.h.  While here,
> add a definition for H_NOOP, a possible return code for H_WATCHDOG.
> 
> Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>

Please provide a change log against the earlier RFC series.

Thanks,
Guenter

> ---
>   arch/powerpc/include/asm/hvcall.h | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h
> index d92a20a85395..4b4f69c35b4f 100644
> --- a/arch/powerpc/include/asm/hvcall.h
> +++ b/arch/powerpc/include/asm/hvcall.h
> @@ -87,6 +87,7 @@
>   #define H_P7		-60
>   #define H_P8		-61
>   #define H_P9		-62
> +#define H_NOOP		-63
>   #define H_TOO_BIG	-64
>   #define H_UNSUPPORTED	-67
>   #define H_OVERLAP	-68
> @@ -324,7 +325,8 @@
>   #define H_RPT_INVALIDATE	0x448
>   #define H_SCM_FLUSH		0x44C
>   #define H_GET_ENERGY_SCALE_INFO	0x450
> -#define MAX_HCALL_OPCODE	H_GET_ENERGY_SCALE_INFO
> +#define H_WATCHDOG		0x45C
> +#define MAX_HCALL_OPCODE	H_WATCHDOG
>   
>   /* Scope args for H_SCM_UNBIND_ALL */
>   #define H_UNBIND_SCOPE_ALL (0x1)


^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH v1 1/4] powerpc/pseries: hvcall.h: add H_WATCHDOG opcode,  H_NOOP return code
@ 2022-05-20 17:44   ` Guenter Roeck
  0 siblings, 0 replies; 12+ messages in thread
From: Guenter Roeck @ 2022-05-20 17:44 UTC (permalink / raw)
  To: Scott Cheloha, linux-watchdog
  Cc: nathanl, wvoigt, aik, vaishnavi, npiggin, tzungbi, brking, linuxppc-dev

On 5/20/22 10:20, Scott Cheloha wrote:
> PAPR v2.12 defines a new hypercall, H_WATCHDOG.  The hypercall permits
> guest control of one or more virtual watchdog timers.
> 
> Add the opcode for the H_WATCHDOG hypercall to hvcall.h.  While here,
> add a definition for H_NOOP, a possible return code for H_WATCHDOG.
> 
> Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>

Please provide a change log against the earlier RFC series.

Thanks,
Guenter

> ---
>   arch/powerpc/include/asm/hvcall.h | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h
> index d92a20a85395..4b4f69c35b4f 100644
> --- a/arch/powerpc/include/asm/hvcall.h
> +++ b/arch/powerpc/include/asm/hvcall.h
> @@ -87,6 +87,7 @@
>   #define H_P7		-60
>   #define H_P8		-61
>   #define H_P9		-62
> +#define H_NOOP		-63
>   #define H_TOO_BIG	-64
>   #define H_UNSUPPORTED	-67
>   #define H_OVERLAP	-68
> @@ -324,7 +325,8 @@
>   #define H_RPT_INVALIDATE	0x448
>   #define H_SCM_FLUSH		0x44C
>   #define H_GET_ENERGY_SCALE_INFO	0x450
> -#define MAX_HCALL_OPCODE	H_GET_ENERGY_SCALE_INFO
> +#define H_WATCHDOG		0x45C
> +#define MAX_HCALL_OPCODE	H_WATCHDOG
>   
>   /* Scope args for H_SCM_UNBIND_ALL */
>   #define H_UNBIND_SCOPE_ALL (0x1)


^ permalink raw reply	[flat|nested] 12+ messages in thread

* [PATCH v1 1/4] powerpc/pseries: hvcall.h: add H_WATCHDOG opcode, H_NOOP return code
  2022-05-20 18:35 [PATCH v1 0/4] pseries-wdt: initial support for PAPR virtual watchdog timers Scott Cheloha
@ 2022-05-20 18:35   ` Scott Cheloha
  0 siblings, 0 replies; 12+ messages in thread
From: Scott Cheloha @ 2022-05-20 18:35 UTC (permalink / raw)
  To: linux-watchdog
  Cc: linux, tzungbi, brking, nathanl, aik, npiggin, vaishnavi, wvoigt,
	linuxppc-dev, Scott Cheloha

PAPR v2.12 defines a new hypercall, H_WATCHDOG.  The hypercall permits
guest control of one or more virtual watchdog timers.

Add the opcode for the H_WATCHDOG hypercall to hvcall.h.  While here,
add a definition for H_NOOP, a possible return code for H_WATCHDOG.

Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>
---
 arch/powerpc/include/asm/hvcall.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h
index d92a20a85395..4b4f69c35b4f 100644
--- a/arch/powerpc/include/asm/hvcall.h
+++ b/arch/powerpc/include/asm/hvcall.h
@@ -87,6 +87,7 @@
 #define H_P7		-60
 #define H_P8		-61
 #define H_P9		-62
+#define H_NOOP		-63
 #define H_TOO_BIG	-64
 #define H_UNSUPPORTED	-67
 #define H_OVERLAP	-68
@@ -324,7 +325,8 @@
 #define H_RPT_INVALIDATE	0x448
 #define H_SCM_FLUSH		0x44C
 #define H_GET_ENERGY_SCALE_INFO	0x450
-#define MAX_HCALL_OPCODE	H_GET_ENERGY_SCALE_INFO
+#define H_WATCHDOG		0x45C
+#define MAX_HCALL_OPCODE	H_WATCHDOG
 
 /* Scope args for H_SCM_UNBIND_ALL */
 #define H_UNBIND_SCOPE_ALL (0x1)
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH v1 1/4] powerpc/pseries: hvcall.h: add H_WATCHDOG opcode, H_NOOP return code
@ 2022-05-20 18:35   ` Scott Cheloha
  0 siblings, 0 replies; 12+ messages in thread
From: Scott Cheloha @ 2022-05-20 18:35 UTC (permalink / raw)
  To: linux-watchdog
  Cc: nathanl, wvoigt, aik, Scott Cheloha, vaishnavi, npiggin, tzungbi,
	brking, linuxppc-dev, linux

PAPR v2.12 defines a new hypercall, H_WATCHDOG.  The hypercall permits
guest control of one or more virtual watchdog timers.

Add the opcode for the H_WATCHDOG hypercall to hvcall.h.  While here,
add a definition for H_NOOP, a possible return code for H_WATCHDOG.

Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>
---
 arch/powerpc/include/asm/hvcall.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h
index d92a20a85395..4b4f69c35b4f 100644
--- a/arch/powerpc/include/asm/hvcall.h
+++ b/arch/powerpc/include/asm/hvcall.h
@@ -87,6 +87,7 @@
 #define H_P7		-60
 #define H_P8		-61
 #define H_P9		-62
+#define H_NOOP		-63
 #define H_TOO_BIG	-64
 #define H_UNSUPPORTED	-67
 #define H_OVERLAP	-68
@@ -324,7 +325,8 @@
 #define H_RPT_INVALIDATE	0x448
 #define H_SCM_FLUSH		0x44C
 #define H_GET_ENERGY_SCALE_INFO	0x450
-#define MAX_HCALL_OPCODE	H_GET_ENERGY_SCALE_INFO
+#define H_WATCHDOG		0x45C
+#define MAX_HCALL_OPCODE	H_WATCHDOG
 
 /* Scope args for H_SCM_UNBIND_ALL */
 #define H_UNBIND_SCOPE_ALL (0x1)
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread

end of thread, other threads:[~2022-05-20 18:38 UTC | newest]

Thread overview: 12+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-05-20 17:20 [PATCH v1 1/4] powerpc/pseries: hvcall.h: add H_WATCHDOG opcode, H_NOOP return code Scott Cheloha
2022-05-20 17:20 ` Scott Cheloha
2022-05-20 17:20 ` [PATCH v1 2/4] powerpc/pseries: add FW_FEATURE_WATCHDOG flag Scott Cheloha
2022-05-20 17:20   ` Scott Cheloha
2022-05-20 17:20 ` [PATCH v1 3/4] powerpc/pseries: register pseries-wdt device with platform bus Scott Cheloha
2022-05-20 17:20   ` Scott Cheloha
2022-05-20 17:20 ` [PATCH v1 4/4] watchdog/pseries-wdt: initial support for PAPR H_WATCHDOG timers Scott Cheloha
2022-05-20 17:20   ` Scott Cheloha
2022-05-20 17:44 ` [PATCH v1 1/4] powerpc/pseries: hvcall.h: add H_WATCHDOG opcode, H_NOOP return code Guenter Roeck
2022-05-20 17:44   ` Guenter Roeck
2022-05-20 18:35 [PATCH v1 0/4] pseries-wdt: initial support for PAPR virtual watchdog timers Scott Cheloha
2022-05-20 18:35 ` [PATCH v1 1/4] powerpc/pseries: hvcall.h: add H_WATCHDOG opcode, H_NOOP return code Scott Cheloha
2022-05-20 18:35   ` Scott Cheloha

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.