diff options
Diffstat (limited to 'drivers/pci/hotplug/s390_pci_hpc.c')
| -rw-r--r-- | drivers/pci/hotplug/s390_pci_hpc.c | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/drivers/pci/hotplug/s390_pci_hpc.c b/drivers/pci/hotplug/s390_pci_hpc.c new file mode 100644 index 000000000..93b5341d2 --- /dev/null +++ b/drivers/pci/hotplug/s390_pci_hpc.c @@ -0,0 +1,206 @@ +// 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 LIST_HEAD(s390_hotplug_slot_list); + +static int zpci_fn_configured(enum zpci_state state) +{ + return state == ZPCI_FN_STATE_CONFIGURED || + state == ZPCI_FN_STATE_ONLINE; +} + +/* + * struct slot - slot information for each *physical* slot + */ +struct slot { + struct list_head slot_list; + struct hotplug_slot *hotplug_slot; + struct zpci_dev *zdev; +}; + +static inline int slot_configure(struct slot *slot) +{ + int ret = sclp_pci_configure(slot->zdev->fid); + + zpci_dbg(3, "conf fid:%x, rc:%d\n", slot->zdev->fid, ret); + if (!ret) + slot->zdev->state = ZPCI_FN_STATE_CONFIGURED; + + return ret; +} + +static inline int slot_deconfigure(struct slot *slot) +{ + int ret = sclp_pci_deconfigure(slot->zdev->fid); + + zpci_dbg(3, "deconf fid:%x, rc:%d\n", slot->zdev->fid, ret); + if (!ret) + slot->zdev->state = ZPCI_FN_STATE_STANDBY; + + return ret; +} + +static int enable_slot(struct hotplug_slot *hotplug_slot) +{ + struct slot *slot = hotplug_slot->private; + int rc; + + if (slot->zdev->state != ZPCI_FN_STATE_STANDBY) + return -EIO; + + rc = slot_configure(slot); + if (rc) + return rc; + + rc = zpci_enable_device(slot->zdev); + if (rc) + goto out_deconfigure; + + pci_scan_slot(slot->zdev->bus, ZPCI_DEVFN); + pci_lock_rescan_remove(); + pci_bus_add_devices(slot->zdev->bus); + pci_unlock_rescan_remove(); + + return rc; + +out_deconfigure: + slot_deconfigure(slot); + return rc; +} + +static int disable_slot(struct hotplug_slot *hotplug_slot) +{ + struct slot *slot = hotplug_slot->private; + struct pci_dev *pdev; + int rc; + + if (!zpci_fn_configured(slot->zdev->state)) + return -EIO; + + pdev = pci_get_slot(slot->zdev->bus, ZPCI_DEVFN); + if (pdev) { + pci_stop_and_remove_bus_device_locked(pdev); + pci_dev_put(pdev); + } + + rc = zpci_disable_device(slot->zdev); + if (rc) + return rc; + + return slot_deconfigure(slot); +} + +static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value) +{ + struct slot *slot = hotplug_slot->private; + + switch (slot->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 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) +{ + struct hotplug_slot *hotplug_slot; + struct hotplug_slot_info *info; + char name[SLOT_NAME_SIZE]; + struct slot *slot; + int rc; + + if (!zdev) + return 0; + + slot = kzalloc(sizeof(*slot), GFP_KERNEL); + if (!slot) + goto error; + + hotplug_slot = kzalloc(sizeof(*hotplug_slot), GFP_KERNEL); + if (!hotplug_slot) + goto error_hp; + hotplug_slot->private = slot; + + slot->hotplug_slot = hotplug_slot; + slot->zdev = zdev; + + info = kzalloc(sizeof(*info), GFP_KERNEL); + if (!info) + goto error_info; + hotplug_slot->info = info; + + hotplug_slot->ops = &s390_hotplug_slot_ops; + + get_power_status(hotplug_slot, &info->power_status); + get_adapter_status(hotplug_slot, &info->adapter_status); + + snprintf(name, SLOT_NAME_SIZE, "%08x", zdev->fid); + rc = pci_hp_register(slot->hotplug_slot, zdev->bus, + ZPCI_DEVFN, name); + if (rc) + goto error_reg; + + list_add(&slot->slot_list, &s390_hotplug_slot_list); + return 0; + +error_reg: + kfree(info); +error_info: + kfree(hotplug_slot); +error_hp: + kfree(slot); +error: + return -ENOMEM; +} + +void zpci_exit_slot(struct zpci_dev *zdev) +{ + struct slot *slot, *next; + + list_for_each_entry_safe(slot, next, &s390_hotplug_slot_list, + slot_list) { + if (slot->zdev != zdev) + continue; + list_del(&slot->slot_list); + pci_hp_deregister(slot->hotplug_slot); + kfree(slot->hotplug_slot->info); + kfree(slot->hotplug_slot); + kfree(slot); + } +} |