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
25 static const struct pci_device_id pvpanic_pci_id_tbl[] = {
26 { PCI_DEVICE(PCI_VENDOR_ID_REDHAT, PCI_DEVICE_ID_REDHAT_PVPANIC)},
27 {}
28 };
29
capability_show(struct device * dev,struct device_attribute * attr,char * buf)30 static ssize_t capability_show(struct device *dev,
31 struct device_attribute *attr, char *buf)
32 {
33 struct pvpanic_instance *pi = dev_get_drvdata(dev);
34
35 return sysfs_emit(buf, "%x\n", pi->capability);
36 }
37 static DEVICE_ATTR_RO(capability);
38
events_show(struct device * dev,struct device_attribute * attr,char * buf)39 static ssize_t events_show(struct device *dev, struct device_attribute *attr, char *buf)
40 {
41 struct pvpanic_instance *pi = dev_get_drvdata(dev);
42
43 return sysfs_emit(buf, "%x\n", pi->events);
44 }
45
events_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)46 static ssize_t events_store(struct device *dev, struct device_attribute *attr,
47 const char *buf, size_t count)
48 {
49 struct pvpanic_instance *pi = dev_get_drvdata(dev);
50 unsigned int tmp;
51 int err;
52
53 err = kstrtouint(buf, 16, &tmp);
54 if (err)
55 return err;
56
57 if ((tmp & pi->capability) != tmp)
58 return -EINVAL;
59
60 pi->events = tmp;
61
62 return count;
63 }
64 static DEVICE_ATTR_RW(events);
65
66 static struct attribute *pvpanic_pci_dev_attrs[] = {
67 &dev_attr_capability.attr,
68 &dev_attr_events.attr,
69 NULL
70 };
71 ATTRIBUTE_GROUPS(pvpanic_pci_dev);
72
pvpanic_pci_probe(struct pci_dev * pdev,const struct pci_device_id * ent)73 static int pvpanic_pci_probe(struct pci_dev *pdev,
74 const struct pci_device_id *ent)
75 {
76 struct pvpanic_instance *pi;
77 void __iomem *base;
78 int ret;
79
80 ret = pcim_enable_device(pdev);
81 if (ret < 0)
82 return ret;
83
84 base = pcim_iomap(pdev, 0, 0);
85 if (!base)
86 return -ENOMEM;
87
88 pi = devm_kmalloc(&pdev->dev, sizeof(*pi), GFP_KERNEL);
89 if (!pi)
90 return -ENOMEM;
91
92 pi->base = base;
93 pi->capability = PVPANIC_PANICKED | PVPANIC_CRASH_LOADED;
94
95 /* initlize capability by RDPT */
96 pi->capability &= ioread8(base);
97 pi->events = pi->capability;
98
99 return devm_pvpanic_probe(&pdev->dev, pi);
100 }
101
102 static struct pci_driver pvpanic_pci_driver = {
103 .name = "pvpanic-pci",
104 .id_table = pvpanic_pci_id_tbl,
105 .probe = pvpanic_pci_probe,
106 .driver = {
107 .dev_groups = pvpanic_pci_dev_groups,
108 },
109 };
110
111 MODULE_DEVICE_TABLE(pci, pvpanic_pci_id_tbl);
112
113 module_pci_driver(pvpanic_pci_driver);
114