linux/drivers/pci/hotplug/s390_pci_hpc.c
Niklas Schnelle f6576a1b48 s390/pci: refactor zpci function states
The current zdev->state mixes the configuration states supported by CLP
with an additional Online state which is used inconsistently to include
enabled zPCI functions which are not yet visible to the common PCI
subsytem. In preparation for a clean separation between architected
configuration states and fine grained function states remove the Online
function state.

Where we previously checked for Online it is more accurate to check if
the function is enabled to avoid an edge case where a disabled device
was still treated as Online. This also simplifies checks whether
a function is configured as this is now directly reflected by its
function state.

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-03-22 11:36:03 +01:00

147 lines
3.0 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 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;
int rc;
if (zdev->state != ZPCI_FN_STATE_CONFIGURED)
return -EIO;
pdev = pci_get_slot(zdev->zbus->bus, zdev->devfn);
if (pdev && pci_num_vf(pdev)) {
pci_dev_put(pdev);
return -EBUSY;
}
pci_dev_put(pdev);
zpci_remove_device(zdev, false);
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);
}