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path: root/drivers/misc/pvpanic/pvpanic-mmio.c
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-rw-r--r--drivers/misc/pvpanic/pvpanic-mmio.c130
1 files changed, 130 insertions, 0 deletions
diff --git a/drivers/misc/pvpanic/pvpanic-mmio.c b/drivers/misc/pvpanic/pvpanic-mmio.c
new file mode 100644
index 000000000..eb97167c0
--- /dev/null
+++ b/drivers/misc/pvpanic/pvpanic-mmio.c
@@ -0,0 +1,130 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Pvpanic MMIO Device Support
+ *
+ * Copyright (C) 2013 Fujitsu.
+ * Copyright (C) 2018 ZTE.
+ * Copyright (C) 2021 Oracle.
+ */
+
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/kexec.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+
+#include <uapi/misc/pvpanic.h>
+
+#include "pvpanic.h"
+
+MODULE_AUTHOR("Hu Tao <hutao@cn.fujitsu.com>");
+MODULE_DESCRIPTION("pvpanic-mmio device driver");
+MODULE_LICENSE("GPL");
+
+static ssize_t capability_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct pvpanic_instance *pi = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%x\n", pi->capability);
+}
+static DEVICE_ATTR_RO(capability);
+
+static ssize_t events_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct pvpanic_instance *pi = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%x\n", pi->events);
+}
+
+static ssize_t events_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct pvpanic_instance *pi = dev_get_drvdata(dev);
+ unsigned int tmp;
+ int err;
+
+ err = kstrtouint(buf, 16, &tmp);
+ if (err)
+ return err;
+
+ if ((tmp & pi->capability) != tmp)
+ return -EINVAL;
+
+ pi->events = tmp;
+
+ return count;
+}
+static DEVICE_ATTR_RW(events);
+
+static struct attribute *pvpanic_mmio_dev_attrs[] = {
+ &dev_attr_capability.attr,
+ &dev_attr_events.attr,
+ NULL
+};
+ATTRIBUTE_GROUPS(pvpanic_mmio_dev);
+
+static int pvpanic_mmio_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct pvpanic_instance *pi;
+ struct resource *res;
+ void __iomem *base;
+
+ res = platform_get_mem_or_io(pdev, 0);
+ if (!res)
+ return -EINVAL;
+
+ switch (resource_type(res)) {
+ case IORESOURCE_IO:
+ base = devm_ioport_map(dev, res->start, resource_size(res));
+ if (!base)
+ return -ENOMEM;
+ break;
+ case IORESOURCE_MEM:
+ base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ pi = devm_kmalloc(dev, sizeof(*pi), GFP_KERNEL);
+ if (!pi)
+ return -ENOMEM;
+
+ pi->base = base;
+ pi->capability = PVPANIC_PANICKED | PVPANIC_CRASH_LOADED;
+
+ /* initialize capability by RDPT */
+ pi->capability &= ioread8(base);
+ pi->events = pi->capability;
+
+ return devm_pvpanic_probe(dev, pi);
+}
+
+static const struct of_device_id pvpanic_mmio_match[] = {
+ { .compatible = "qemu,pvpanic-mmio", },
+ {}
+};
+MODULE_DEVICE_TABLE(of, pvpanic_mmio_match);
+
+static const struct acpi_device_id pvpanic_device_ids[] = {
+ { "QEMU0001", 0 },
+ { "", 0 }
+};
+MODULE_DEVICE_TABLE(acpi, pvpanic_device_ids);
+
+static struct platform_driver pvpanic_mmio_driver = {
+ .driver = {
+ .name = "pvpanic-mmio",
+ .of_match_table = pvpanic_mmio_match,
+ .acpi_match_table = pvpanic_device_ids,
+ .dev_groups = pvpanic_mmio_dev_groups,
+ },
+ .probe = pvpanic_mmio_probe,
+};
+module_platform_driver(pvpanic_mmio_driver);