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authorHu Tao <hutao@cn.fujitsu.com>2013-05-08 11:15:32 +0800
committerMatthew Garrett <matthew.garrett@nebula.com>2013-05-08 19:59:52 -0400
commit8b10acd74cdad9063c7a63468e31759d9ac877d9 (patch)
tree5725bbe99b4fe8393486bd7023c4313e8f2f2963 /drivers/platform
parenta849e0024a84480c7be85e3b723610e14042751b (diff)
downloadlinux-8b10acd74cdad9063c7a63468e31759d9ac877d9.tar.bz2
pvpanic: pvpanic device driver
pvpanic device is a qemu simulated device through which guest panic event is sent to host. Signed-off-by: Hu Tao <hutao@cn.fujitsu.com> Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Diffstat (limited to 'drivers/platform')
-rw-r--r--drivers/platform/x86/Kconfig8
-rw-r--r--drivers/platform/x86/Makefile2
-rw-r--r--drivers/platform/x86/pvpanic.c124
3 files changed, 134 insertions, 0 deletions
diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index 3338437b559b..85772616efbf 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -781,4 +781,12 @@ config APPLE_GMUX
graphics as well as the backlight. Currently only backlight
control is supported by the driver.
+config PVPANIC
+ tristate "pvpanic device support"
+ depends on ACPI
+ ---help---
+ This driver provides support for the pvpanic device. pvpanic is
+ a paravirtualized device provided by QEMU; it lets a virtual machine
+ (guest) communicate panic events to the host.
+
endif # X86_PLATFORM_DEVICES
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index ace2b38942fe..ef0ec746f78c 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -51,3 +51,5 @@ obj-$(CONFIG_INTEL_OAKTRAIL) += intel_oaktrail.o
obj-$(CONFIG_SAMSUNG_Q10) += samsung-q10.o
obj-$(CONFIG_APPLE_GMUX) += apple-gmux.o
obj-$(CONFIG_CHROMEOS_LAPTOP) += chromeos_laptop.o
+
+obj-$(CONFIG_PVPANIC) += pvpanic.o
diff --git a/drivers/platform/x86/pvpanic.c b/drivers/platform/x86/pvpanic.c
new file mode 100644
index 000000000000..47ae0c47d4b5
--- /dev/null
+++ b/drivers/platform/x86/pvpanic.c
@@ -0,0 +1,124 @@
+/*
+ * pvpanic.c - pvpanic Device Support
+ *
+ * Copyright (C) 2013 Fujitsu.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <acpi/acpi_bus.h>
+#include <acpi/acpi_drivers.h>
+
+MODULE_AUTHOR("Hu Tao <hutao@cn.fujitsu.com>");
+MODULE_DESCRIPTION("pvpanic device driver");
+MODULE_LICENSE("GPL");
+
+static int pvpanic_add(struct acpi_device *device);
+static int pvpanic_remove(struct acpi_device *device);
+
+static const struct acpi_device_id pvpanic_device_ids[] = {
+ { "QEMU0001", 0 },
+ { "", 0 },
+};
+MODULE_DEVICE_TABLE(acpi, pvpanic_device_ids);
+
+#define PVPANIC_PANICKED (1 << 0)
+
+static u16 port;
+
+static struct acpi_driver pvpanic_driver = {
+ .name = "pvpanic",
+ .class = "QEMU",
+ .ids = pvpanic_device_ids,
+ .ops = {
+ .add = pvpanic_add,
+ .remove = pvpanic_remove,
+ },
+ .owner = THIS_MODULE,
+};
+
+static void
+pvpanic_send_event(unsigned int event)
+{
+ outb(event, port);
+}
+
+static int
+pvpanic_panic_notify(struct notifier_block *nb, unsigned long code,
+ void *unused)
+{
+ pvpanic_send_event(PVPANIC_PANICKED);
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block pvpanic_panic_nb = {
+ .notifier_call = pvpanic_panic_notify,
+};
+
+
+static acpi_status
+pvpanic_walk_resources(struct acpi_resource *res, void *context)
+{
+ switch (res->type) {
+ case ACPI_RESOURCE_TYPE_END_TAG:
+ return AE_OK;
+
+ case ACPI_RESOURCE_TYPE_IO:
+ port = res->data.io.minimum;
+ return AE_OK;
+
+ default:
+ return AE_ERROR;
+ }
+}
+
+static int pvpanic_add(struct acpi_device *device)
+{
+ acpi_status status;
+ u64 ret;
+
+ status = acpi_evaluate_integer(device->handle, "_STA", NULL,
+ &ret);
+
+ if (ACPI_FAILURE(status) || (ret & 0x0B) != 0x0B)
+ return -ENODEV;
+
+ acpi_walk_resources(device->handle, METHOD_NAME__CRS,
+ pvpanic_walk_resources, NULL);
+
+ if (!port)
+ return -ENODEV;
+
+ atomic_notifier_chain_register(&panic_notifier_list,
+ &pvpanic_panic_nb);
+
+ return 0;
+}
+
+static int pvpanic_remove(struct acpi_device *device)
+{
+
+ atomic_notifier_chain_unregister(&panic_notifier_list,
+ &pvpanic_panic_nb);
+ return 0;
+}
+
+module_acpi_driver(pvpanic_driver);