linux/drivers/pci/hotplug/s390_pci_hpc.c
Pierre Morel 44510d6fa0 s390/pci: Handling multifunctions
We allow multiple functions on a single bus.
We suppress the ZPCI_DEVFN definition and replace its
occurences with zpci->devfn.

We verify the number of device during the registration.

There can never be more domains in use than existing
devices, so we do not need to verify the count of domain
after having verified the count of devices.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-28 13:49:47 +02:00

151 lines
3.1 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* PCI Hot Plug Controller Driver for System z
*
* Copyright 2012 IBM Corp.
*
* Author(s):
* Jan Glauber <jang@linux.vnet.ibm.com>
*/
#define KMSG_COMPONENT "zpci"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/pci.h>
#include <linux/pci_hotplug.h>
#include <asm/pci_debug.h>
#include <asm/sclp.h>
#define SLOT_NAME_SIZE 10
static int zpci_fn_configured(enum zpci_state state)
{
return state == ZPCI_FN_STATE_CONFIGURED ||
state == ZPCI_FN_STATE_ONLINE;
}
static inline int zdev_configure(struct zpci_dev *zdev)
{
int ret = sclp_pci_configure(zdev->fid);
zpci_dbg(3, "conf fid:%x, rc:%d\n", zdev->fid, ret);
if (!ret)
zdev->state = ZPCI_FN_STATE_CONFIGURED;
return ret;
}
static inline int zdev_deconfigure(struct zpci_dev *zdev)
{
int ret = sclp_pci_deconfigure(zdev->fid);
zpci_dbg(3, "deconf fid:%x, rc:%d\n", zdev->fid, ret);
if (!ret)
zdev->state = ZPCI_FN_STATE_STANDBY;
return ret;
}
static int enable_slot(struct hotplug_slot *hotplug_slot)
{
struct zpci_dev *zdev = container_of(hotplug_slot, struct zpci_dev,
hotplug_slot);
struct zpci_bus *zbus = zdev->zbus;
int rc;
if (zdev->state != ZPCI_FN_STATE_STANDBY)
return -EIO;
rc = zdev_configure(zdev);
if (rc)
return rc;
rc = zpci_enable_device(zdev);
if (rc)
goto out_deconfigure;
pci_scan_slot(zbus->bus, zdev->devfn);
pci_lock_rescan_remove();
pci_bus_add_devices(zbus->bus);
pci_unlock_rescan_remove();
return rc;
out_deconfigure:
zdev_deconfigure(zdev);
return rc;
}
static int disable_slot(struct hotplug_slot *hotplug_slot)
{
struct zpci_dev *zdev = container_of(hotplug_slot, struct zpci_dev,
hotplug_slot);
struct pci_dev *pdev;
struct zpci_bus *zbus = zdev->zbus;
int rc;
if (!zpci_fn_configured(zdev->state))
return -EIO;
pdev = pci_get_slot(zbus->bus, zdev->devfn);
if (pdev) {
pci_stop_and_remove_bus_device_locked(pdev);
pci_dev_put(pdev);
}
rc = zpci_disable_device(zdev);
if (rc)
return rc;
return zdev_deconfigure(zdev);
}
static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
struct zpci_dev *zdev = container_of(hotplug_slot, struct zpci_dev,
hotplug_slot);
switch (zdev->state) {
case ZPCI_FN_STATE_STANDBY:
*value = 0;
break;
default:
*value = 1;
break;
}
return 0;
}
static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
/* if the slot exits it always contains a function */
*value = 1;
return 0;
}
static const struct hotplug_slot_ops s390_hotplug_slot_ops = {
.enable_slot = enable_slot,
.disable_slot = disable_slot,
.get_power_status = get_power_status,
.get_adapter_status = get_adapter_status,
};
int zpci_init_slot(struct zpci_dev *zdev)
{
char name[SLOT_NAME_SIZE];
struct zpci_bus *zbus = zdev->zbus;
zdev->hotplug_slot.ops = &s390_hotplug_slot_ops;
snprintf(name, SLOT_NAME_SIZE, "%08x", zdev->fid);
return pci_hp_register(&zdev->hotplug_slot, zbus->bus,
zdev->devfn, name);
}
void zpci_exit_slot(struct zpci_dev *zdev)
{
pci_hp_deregister(&zdev->hotplug_slot);
}