tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
21MODULE_AUTHOR("Mihai Carabas <mihai.carabas@oracle.com>");
22MODULE_DESCRIPTION("pvpanic device driver ");
23MODULE_LICENSE("GPL");
24
25static const struct pci_device_id pvpanic_pci_id_tbl[] = {
26 { PCI_DEVICE(PCI_VENDOR_ID_REDHAT, PCI_DEVICE_ID_REDHAT_PVPANIC)},
27 {}
28};
29
30static 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}
37static DEVICE_ATTR_RO(capability);
38
39static 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
46static 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}
64static DEVICE_ATTR_RW(events);
65
66static struct attribute *pvpanic_pci_dev_attrs[] = {
67 &dev_attr_capability.attr,
68 &dev_attr_events.attr,
69 NULL
70};
71ATTRIBUTE_GROUPS(pvpanic_pci_dev);
72
73static 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
102static 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
111module_pci_driver(pvpanic_pci_driver);