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-rw-r--r--drivers/misc/pvpanic.c192
1 files changed, 192 insertions, 0 deletions
diff --git a/drivers/misc/pvpanic.c b/drivers/misc/pvpanic.c
new file mode 100644
index 000000000000..595ac065b401
--- /dev/null
+++ b/drivers/misc/pvpanic.c
@@ -0,0 +1,192 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Pvpanic Device Support
+ *
+ * Copyright (C) 2013 Fujitsu.
+ * Copyright (C) 2018 ZTE.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/acpi.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+
+static void __iomem *base;
+
+#define PVPANIC_PANICKED (1 << 0)
+
+MODULE_AUTHOR("Hu Tao <hutao@cn.fujitsu.com>");
+MODULE_DESCRIPTION("pvpanic device driver");
+MODULE_LICENSE("GPL");
+
+static void
+pvpanic_send_event(unsigned int event)
+{
+ iowrite8(event, base);
+}
+
+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,
+ .priority = 1, /* let this called before broken drm_fb_helper */
+};
+
+#ifdef CONFIG_ACPI
+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);
+
+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 acpi_status
+pvpanic_walk_resources(struct acpi_resource *res, void *context)
+{
+ struct resource r;
+
+ if (acpi_dev_resource_io(res, &r)) {
+ base = ioport_map(r.start, resource_size(&r));
+ return AE_OK;
+ } else if (acpi_dev_resource_memory(res, &r)) {
+ base = ioremap(r.start, resource_size(&r));
+ return AE_OK;
+ }
+
+ return AE_ERROR;
+}
+
+static int pvpanic_add(struct acpi_device *device)
+{
+ int ret;
+
+ ret = acpi_bus_get_status(device);
+ if (ret < 0)
+ return ret;
+
+ if (!device->status.enabled || !device->status.functional)
+ return -ENODEV;
+
+ acpi_walk_resources(device->handle, METHOD_NAME__CRS,
+ pvpanic_walk_resources, NULL);
+
+ if (!base)
+ 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);
+ iounmap(base);
+
+ return 0;
+}
+
+static int pvpanic_register_acpi_driver(void)
+{
+ return acpi_bus_register_driver(&pvpanic_driver);
+}
+
+static void pvpanic_unregister_acpi_driver(void)
+{
+ acpi_bus_unregister_driver(&pvpanic_driver);
+}
+#else
+static int pvpanic_register_acpi_driver(void)
+{
+ return -ENODEV;
+}
+
+static void pvpanic_unregister_acpi_driver(void) {}
+#endif
+
+static int pvpanic_mmio_probe(struct platform_device *pdev)
+{
+ struct resource *mem;
+
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!mem)
+ return -EINVAL;
+
+ base = devm_ioremap_resource(&pdev->dev, mem);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ atomic_notifier_chain_register(&panic_notifier_list,
+ &pvpanic_panic_nb);
+
+ return 0;
+}
+
+static int pvpanic_mmio_remove(struct platform_device *pdev)
+{
+
+ atomic_notifier_chain_unregister(&panic_notifier_list,
+ &pvpanic_panic_nb);
+
+ return 0;
+}
+
+static const struct of_device_id pvpanic_mmio_match[] = {
+ { .compatible = "qemu,pvpanic-mmio", },
+ {}
+};
+
+static struct platform_driver pvpanic_mmio_driver = {
+ .driver = {
+ .name = "pvpanic-mmio",
+ .of_match_table = pvpanic_mmio_match,
+ },
+ .probe = pvpanic_mmio_probe,
+ .remove = pvpanic_mmio_remove,
+};
+
+static int __init pvpanic_mmio_init(void)
+{
+ if (acpi_disabled)
+ return platform_driver_register(&pvpanic_mmio_driver);
+ else
+ return pvpanic_register_acpi_driver();
+}
+
+static void __exit pvpanic_mmio_exit(void)
+{
+ if (acpi_disabled)
+ platform_driver_unregister(&pvpanic_mmio_driver);
+ else
+ pvpanic_unregister_acpi_driver();
+}
+
+module_init(pvpanic_mmio_init);
+module_exit(pvpanic_mmio_exit);