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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 | // 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); |