diff options
Diffstat (limited to 'drivers/misc/pvpanic/pvpanic-mmio.c')
-rw-r--r-- | drivers/misc/pvpanic/pvpanic-mmio.c | 130 |
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 0000000000..eb97167c03 --- /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); |