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authorLinus Torvalds <torvalds@linux-foundation.org>2016-03-01 08:57:34 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2016-03-01 08:57:34 -0800
commit7d46af2084eabe73ce4dbf06072fded34b58b0c7 (patch)
tree3b7be860d274f98257648c202f81016bc841148c /drivers/watchdog
parentLinux 4.5-rc6 (diff)
parentsparc64: Fix sparc64_set_context stack handling. (diff)
downloadlinux-dev-7d46af2084eabe73ce4dbf06072fded34b58b0c7.tar.xz
linux-dev-7d46af2084eabe73ce4dbf06072fded34b58b0c7.zip
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
Pull sparc fixes from David Miller: 1) System call tracing doesn't handle register contents properly across the trace. From Mike Frysinger. 2) Hook up copy_file_range 3) Build fix for 32-bit with newer tools. 4) New sun4v watchdog driver, from Wim Coekaerts. 5) Set context system call has to allow for servicable faults when we flush the register windows to memory * git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc: sparc64: Fix sparc64_set_context stack handling. sparc32: Add -Wa,-Av8 to KBUILD_CFLAGS. Add sun4v_wdt watchdog driver sparc: Fix system call tracing register handling. sparc: Hook up copy_file_range syscall.
Diffstat (limited to 'drivers/watchdog')
-rw-r--r--drivers/watchdog/Kconfig11
-rw-r--r--drivers/watchdog/Makefile1
-rw-r--r--drivers/watchdog/sun4v_wdt.c191
3 files changed, 203 insertions, 0 deletions
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 0f6d8515ba4f..80825a7e8e48 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -1569,6 +1569,17 @@ config WATCHDOG_RIO
machines. The watchdog timeout period is normally one minute but
can be changed with a boot-time parameter.
+config WATCHDOG_SUN4V
+ tristate "Sun4v Watchdog support"
+ select WATCHDOG_CORE
+ depends on SPARC64
+ help
+ Say Y here to support the hypervisor watchdog capability embedded
+ in the SPARC sun4v architecture.
+
+ To compile this driver as a module, choose M here. The module will
+ be called sun4v_wdt.
+
# XTENSA Architecture
# Xen Architecture
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index f566753256ab..f6a6a387c6c7 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -179,6 +179,7 @@ obj-$(CONFIG_SH_WDT) += shwdt.o
obj-$(CONFIG_WATCHDOG_RIO) += riowd.o
obj-$(CONFIG_WATCHDOG_CP1XXX) += cpwd.o
+obj-$(CONFIG_WATCHDOG_SUN4V) += sun4v_wdt.o
# XTENSA Architecture
diff --git a/drivers/watchdog/sun4v_wdt.c b/drivers/watchdog/sun4v_wdt.c
new file mode 100644
index 000000000000..1467fe50a76f
--- /dev/null
+++ b/drivers/watchdog/sun4v_wdt.c
@@ -0,0 +1,191 @@
+/*
+ * sun4v watchdog timer
+ * (c) Copyright 2016 Oracle Corporation
+ *
+ * Implement a simple watchdog driver using the built-in sun4v hypervisor
+ * watchdog support. If time expires, the hypervisor stops or bounces
+ * the guest domain.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/watchdog.h>
+#include <asm/hypervisor.h>
+#include <asm/mdesc.h>
+
+#define WDT_TIMEOUT 60
+#define WDT_MAX_TIMEOUT 31536000
+#define WDT_MIN_TIMEOUT 1
+#define WDT_DEFAULT_RESOLUTION_MS 1000 /* 1 second */
+
+static unsigned int timeout;
+module_param(timeout, uint, 0);
+MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds (default="
+ __MODULE_STRING(WDT_TIMEOUT) ")");
+
+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) ")");
+
+static int sun4v_wdt_stop(struct watchdog_device *wdd)
+{
+ sun4v_mach_set_watchdog(0, NULL);
+
+ return 0;
+}
+
+static int sun4v_wdt_ping(struct watchdog_device *wdd)
+{
+ int hverr;
+
+ /*
+ * HV watchdog timer will round up the timeout
+ * passed in to the nearest multiple of the
+ * watchdog resolution in milliseconds.
+ */
+ hverr = sun4v_mach_set_watchdog(wdd->timeout * 1000, NULL);
+ if (hverr == HV_EINVAL)
+ return -EINVAL;
+
+ return 0;
+}
+
+static int sun4v_wdt_set_timeout(struct watchdog_device *wdd,
+ unsigned int timeout)
+{
+ wdd->timeout = timeout;
+
+ return 0;
+}
+
+static const struct watchdog_info sun4v_wdt_ident = {
+ .options = WDIOF_SETTIMEOUT |
+ WDIOF_MAGICCLOSE |
+ WDIOF_KEEPALIVEPING,
+ .identity = "sun4v hypervisor watchdog",
+ .firmware_version = 0,
+};
+
+static struct watchdog_ops sun4v_wdt_ops = {
+ .owner = THIS_MODULE,
+ .start = sun4v_wdt_ping,
+ .stop = sun4v_wdt_stop,
+ .ping = sun4v_wdt_ping,
+ .set_timeout = sun4v_wdt_set_timeout,
+};
+
+static struct watchdog_device wdd = {
+ .info = &sun4v_wdt_ident,
+ .ops = &sun4v_wdt_ops,
+ .min_timeout = WDT_MIN_TIMEOUT,
+ .max_timeout = WDT_MAX_TIMEOUT,
+ .timeout = WDT_TIMEOUT,
+};
+
+static int __init sun4v_wdt_init(void)
+{
+ struct mdesc_handle *handle;
+ u64 node;
+ const u64 *value;
+ int err = 0;
+ unsigned long major = 1, minor = 1;
+
+ /*
+ * There are 2 properties that can be set from the control
+ * domain for the watchdog.
+ * watchdog-resolution
+ * watchdog-max-timeout
+ *
+ * We can expect a handle to be returned otherwise something
+ * serious is wrong. Correct to return -ENODEV here.
+ */
+
+ handle = mdesc_grab();
+ if (!handle)
+ return -ENODEV;
+
+ node = mdesc_node_by_name(handle, MDESC_NODE_NULL, "platform");
+ err = -ENODEV;
+ if (node == MDESC_NODE_NULL)
+ goto out_release;
+
+ /*
+ * This is a safe way to validate if we are on the right
+ * platform.
+ */
+ if (sun4v_hvapi_register(HV_GRP_CORE, major, &minor))
+ goto out_hv_unreg;
+
+ /* Allow value of watchdog-resolution up to 1s (default) */
+ value = mdesc_get_property(handle, node, "watchdog-resolution", NULL);
+ err = -EINVAL;
+ if (value) {
+ if (*value == 0 ||
+ *value > WDT_DEFAULT_RESOLUTION_MS)
+ goto out_hv_unreg;
+ }
+
+ value = mdesc_get_property(handle, node, "watchdog-max-timeout", NULL);
+ if (value) {
+ /*
+ * If the property value (in ms) is smaller than
+ * min_timeout, return -EINVAL.
+ */
+ if (*value < wdd.min_timeout * 1000)
+ goto out_hv_unreg;
+
+ /*
+ * If the property value is smaller than
+ * default max_timeout then set watchdog max_timeout to
+ * the value of the property in seconds.
+ */
+ if (*value < wdd.max_timeout * 1000)
+ wdd.max_timeout = *value / 1000;
+ }
+
+ watchdog_init_timeout(&wdd, timeout, NULL);
+
+ watchdog_set_nowayout(&wdd, nowayout);
+
+ err = watchdog_register_device(&wdd);
+ if (err)
+ goto out_hv_unreg;
+
+ pr_info("initialized (timeout=%ds, nowayout=%d)\n",
+ wdd.timeout, nowayout);
+
+ mdesc_release(handle);
+
+ return 0;
+
+out_hv_unreg:
+ sun4v_hvapi_unregister(HV_GRP_CORE);
+
+out_release:
+ mdesc_release(handle);
+ return err;
+}
+
+static void __exit sun4v_wdt_exit(void)
+{
+ sun4v_hvapi_unregister(HV_GRP_CORE);
+ watchdog_unregister_device(&wdd);
+}
+
+module_init(sun4v_wdt_init);
+module_exit(sun4v_wdt_exit);
+
+MODULE_AUTHOR("Wim Coekaerts <wim.coekaerts@oracle.com>");
+MODULE_DESCRIPTION("sun4v watchdog driver");
+MODULE_LICENSE("GPL");