linuxdebug/drivers/misc/pvpanic/pvpanic-pci.c

110 lines
2.4 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Pvpanic PCI Device Support
*
* Copyright (C) 2021 Oracle.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <uapi/misc/pvpanic.h>
#include "pvpanic.h"
#define PCI_VENDOR_ID_REDHAT 0x1b36
#define PCI_DEVICE_ID_REDHAT_PVPANIC 0x0011
MODULE_AUTHOR("Mihai Carabas <mihai.carabas@oracle.com>");
MODULE_DESCRIPTION("pvpanic 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_pci_dev_attrs[] = {
&dev_attr_capability.attr,
&dev_attr_events.attr,
NULL
};
ATTRIBUTE_GROUPS(pvpanic_pci_dev);
static int pvpanic_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
struct pvpanic_instance *pi;
void __iomem *base;
int ret;
ret = pcim_enable_device(pdev);
if (ret < 0)
return ret;
base = pcim_iomap(pdev, 0, 0);
if (!base)
return -ENOMEM;
pi = devm_kmalloc(&pdev->dev, sizeof(*pi), GFP_KERNEL);
if (!pi)
return -ENOMEM;
pi->base = base;
pi->capability = PVPANIC_PANICKED | PVPANIC_CRASH_LOADED;
/* initlize capability by RDPT */
pi->capability &= ioread8(base);
pi->events = pi->capability;
return devm_pvpanic_probe(&pdev->dev, pi);
}
static const struct pci_device_id pvpanic_pci_id_tbl[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_REDHAT, PCI_DEVICE_ID_REDHAT_PVPANIC)},
{}
};
MODULE_DEVICE_TABLE(pci, pvpanic_pci_id_tbl);
static struct pci_driver pvpanic_pci_driver = {
.name = "pvpanic-pci",
.id_table = pvpanic_pci_id_tbl,
.probe = pvpanic_pci_probe,
.driver = {
.dev_groups = pvpanic_pci_dev_groups,
},
};
module_pci_driver(pvpanic_pci_driver);