1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Pvpanic PCI Device Support
4 *
5 * Copyright (C) 2021 Oracle.
6 */
7
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/pci.h>
11 #include <linux/types.h>
12 #include <linux/slab.h>
13
14 #include <uapi/misc/pvpanic.h>
15
16 #include "pvpanic.h"
17
18 #define PCI_VENDOR_ID_REDHAT 0x1b36
19 #define PCI_DEVICE_ID_REDHAT_PVPANIC 0x0011
20
21 MODULE_AUTHOR("Mihai Carabas <mihai.carabas@oracle.com>");
22 MODULE_DESCRIPTION("pvpanic device driver");
23 MODULE_LICENSE("GPL");
24
capability_show(struct device * dev,struct device_attribute * attr,char * buf)25 static ssize_t capability_show(struct device *dev, struct device_attribute *attr, char *buf)
26 {
27 struct pvpanic_instance *pi = dev_get_drvdata(dev);
28
29 return sysfs_emit(buf, "%x\n", pi->capability);
30 }
31 static DEVICE_ATTR_RO(capability);
32
events_show(struct device * dev,struct device_attribute * attr,char * buf)33 static ssize_t events_show(struct device *dev, struct device_attribute *attr, char *buf)
34 {
35 struct pvpanic_instance *pi = dev_get_drvdata(dev);
36
37 return sysfs_emit(buf, "%x\n", pi->events);
38 }
39
events_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)40 static ssize_t events_store(struct device *dev, struct device_attribute *attr,
41 const char *buf, size_t count)
42 {
43 struct pvpanic_instance *pi = dev_get_drvdata(dev);
44 unsigned int tmp;
45 int err;
46
47 err = kstrtouint(buf, 16, &tmp);
48 if (err)
49 return err;
50
51 if ((tmp & pi->capability) != tmp)
52 return -EINVAL;
53
54 pi->events = tmp;
55
56 return count;
57 }
58 static DEVICE_ATTR_RW(events);
59
60 static struct attribute *pvpanic_pci_dev_attrs[] = {
61 &dev_attr_capability.attr,
62 &dev_attr_events.attr,
63 NULL
64 };
65 ATTRIBUTE_GROUPS(pvpanic_pci_dev);
66
pvpanic_pci_probe(struct pci_dev * pdev,const struct pci_device_id * ent)67 static int pvpanic_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
68 {
69 struct pvpanic_instance *pi;
70 void __iomem *base;
71 int ret;
72
73 ret = pcim_enable_device(pdev);
74 if (ret < 0)
75 return ret;
76
77 base = pcim_iomap(pdev, 0, 0);
78 if (!base)
79 return -ENOMEM;
80
81 pi = devm_kmalloc(&pdev->dev, sizeof(*pi), GFP_KERNEL);
82 if (!pi)
83 return -ENOMEM;
84
85 pi->base = base;
86 pi->capability = PVPANIC_PANICKED | PVPANIC_CRASH_LOADED;
87
88 /* initlize capability by RDPT */
89 pi->capability &= ioread8(base);
90 pi->events = pi->capability;
91
92 return devm_pvpanic_probe(&pdev->dev, pi);
93 }
94
95 static const struct pci_device_id pvpanic_pci_id_tbl[] = {
96 { PCI_DEVICE(PCI_VENDOR_ID_REDHAT, PCI_DEVICE_ID_REDHAT_PVPANIC)},
97 {}
98 };
99 MODULE_DEVICE_TABLE(pci, pvpanic_pci_id_tbl);
100
101 static struct pci_driver pvpanic_pci_driver = {
102 .name = "pvpanic-pci",
103 .id_table = pvpanic_pci_id_tbl,
104 .probe = pvpanic_pci_probe,
105 .driver = {
106 .dev_groups = pvpanic_pci_dev_groups,
107 },
108 };
109 module_pci_driver(pvpanic_pci_driver);
110