diff options
Diffstat (limited to 'drivers/pci/hotplug/cpci_hotplug_core.c')
| -rw-r--r-- | drivers/pci/hotplug/cpci_hotplug_core.c | 724 |
1 files changed, 724 insertions, 0 deletions
diff --git a/drivers/pci/hotplug/cpci_hotplug_core.c b/drivers/pci/hotplug/cpci_hotplug_core.c new file mode 100644 index 00000000..3fadf2f1 --- /dev/null +++ b/drivers/pci/hotplug/cpci_hotplug_core.c @@ -0,0 +1,724 @@ +/* + * CompactPCI Hot Plug Driver + * + * Copyright (C) 2002,2005 SOMA Networks, Inc. + * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com) + * Copyright (C) 2001 IBM Corp. + * + * All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or (at + * your option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for more + * details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * + * Send feedback to <scottm@somanetworks.com> + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/pci.h> +#include <linux/pci_hotplug.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/atomic.h> +#include <linux/delay.h> +#include <linux/kthread.h> +#include "cpci_hotplug.h" + +#define DRIVER_AUTHOR "Scott Murray <scottm@somanetworks.com>" +#define DRIVER_DESC "CompactPCI Hot Plug Core" + +#define MY_NAME "cpci_hotplug" + +#define dbg(format, arg...) \ + do { \ + if (cpci_debug) \ + printk (KERN_DEBUG "%s: " format "\n", \ + MY_NAME , ## arg); \ + } while (0) +#define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME , ## arg) +#define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME , ## arg) +#define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME , ## arg) + +/* local variables */ +static DECLARE_RWSEM(list_rwsem); +static LIST_HEAD(slot_list); +static int slots; +static atomic_t extracting; +int cpci_debug; +static struct cpci_hp_controller *controller; +static struct task_struct *cpci_thread; +static int thread_finished; + +static int enable_slot(struct hotplug_slot *slot); +static int disable_slot(struct hotplug_slot *slot); +static int set_attention_status(struct hotplug_slot *slot, u8 value); +static int get_power_status(struct hotplug_slot *slot, u8 * value); +static int get_attention_status(struct hotplug_slot *slot, u8 * value); +static int get_adapter_status(struct hotplug_slot *slot, u8 * value); +static int get_latch_status(struct hotplug_slot *slot, u8 * value); + +static struct hotplug_slot_ops cpci_hotplug_slot_ops = { + .enable_slot = enable_slot, + .disable_slot = disable_slot, + .set_attention_status = set_attention_status, + .get_power_status = get_power_status, + .get_attention_status = get_attention_status, + .get_adapter_status = get_adapter_status, + .get_latch_status = get_latch_status, +}; + +static int +update_latch_status(struct hotplug_slot *hotplug_slot, u8 value) +{ + struct hotplug_slot_info info; + + memcpy(&info, hotplug_slot->info, sizeof(struct hotplug_slot_info)); + info.latch_status = value; + return pci_hp_change_slot_info(hotplug_slot, &info); +} + +static int +update_adapter_status(struct hotplug_slot *hotplug_slot, u8 value) +{ + struct hotplug_slot_info info; + + memcpy(&info, hotplug_slot->info, sizeof(struct hotplug_slot_info)); + info.adapter_status = value; + return pci_hp_change_slot_info(hotplug_slot, &info); +} + +static int +enable_slot(struct hotplug_slot *hotplug_slot) +{ + struct slot *slot = hotplug_slot->private; + int retval = 0; + + dbg("%s - physical_slot = %s", __func__, slot_name(slot)); + + if (controller->ops->set_power) + retval = controller->ops->set_power(slot, 1); + return retval; +} + +static int +disable_slot(struct hotplug_slot *hotplug_slot) +{ + struct slot *slot = hotplug_slot->private; + int retval = 0; + + dbg("%s - physical_slot = %s", __func__, slot_name(slot)); + + down_write(&list_rwsem); + + /* Unconfigure device */ + dbg("%s - unconfiguring slot %s", __func__, slot_name(slot)); + if ((retval = cpci_unconfigure_slot(slot))) { + err("%s - could not unconfigure slot %s", + __func__, slot_name(slot)); + goto disable_error; + } + dbg("%s - finished unconfiguring slot %s", __func__, slot_name(slot)); + + /* Clear EXT (by setting it) */ + if (cpci_clear_ext(slot)) { + err("%s - could not clear EXT for slot %s", + __func__, slot_name(slot)); + retval = -ENODEV; + goto disable_error; + } + cpci_led_on(slot); + + if (controller->ops->set_power) + if ((retval = controller->ops->set_power(slot, 0))) + goto disable_error; + + if (update_adapter_status(slot->hotplug_slot, 0)) + warn("failure to update adapter file"); + + if (slot->extracting) { + slot->extracting = 0; + atomic_dec(&extracting); + } +disable_error: + up_write(&list_rwsem); + return retval; +} + +static u8 +cpci_get_power_status(struct slot *slot) +{ + u8 power = 1; + + if (controller->ops->get_power) + power = controller->ops->get_power(slot); + return power; +} + +static int +get_power_status(struct hotplug_slot *hotplug_slot, u8 * value) +{ + struct slot *slot = hotplug_slot->private; + + *value = cpci_get_power_status(slot); + return 0; +} + +static int +get_attention_status(struct hotplug_slot *hotplug_slot, u8 * value) +{ + struct slot *slot = hotplug_slot->private; + + *value = cpci_get_attention_status(slot); + return 0; +} + +static int +set_attention_status(struct hotplug_slot *hotplug_slot, u8 status) +{ + return cpci_set_attention_status(hotplug_slot->private, status); +} + +static int +get_adapter_status(struct hotplug_slot *hotplug_slot, u8 * value) +{ + *value = hotplug_slot->info->adapter_status; + return 0; +} + +static int +get_latch_status(struct hotplug_slot *hotplug_slot, u8 * value) +{ + *value = hotplug_slot->info->latch_status; + return 0; +} + +static void release_slot(struct hotplug_slot *hotplug_slot) +{ + struct slot *slot = hotplug_slot->private; + + kfree(slot->hotplug_slot->info); + kfree(slot->hotplug_slot); + if (slot->dev) + pci_dev_put(slot->dev); + kfree(slot); +} + +#define SLOT_NAME_SIZE 6 + +int +cpci_hp_register_bus(struct pci_bus *bus, u8 first, u8 last) +{ + struct slot *slot; + struct hotplug_slot *hotplug_slot; + struct hotplug_slot_info *info; + char name[SLOT_NAME_SIZE]; + int status = -ENOMEM; + int i; + + if (!(controller && bus)) + return -ENODEV; + + /* + * Create a structure for each slot, and register that slot + * with the pci_hotplug subsystem. + */ + for (i = first; i <= last; ++i) { + slot = kzalloc(sizeof (struct slot), GFP_KERNEL); + if (!slot) + goto error; + + hotplug_slot = + kzalloc(sizeof (struct hotplug_slot), GFP_KERNEL); + if (!hotplug_slot) + goto error_slot; + slot->hotplug_slot = hotplug_slot; + + info = kzalloc(sizeof (struct hotplug_slot_info), GFP_KERNEL); + if (!info) + goto error_hpslot; + hotplug_slot->info = info; + + slot->bus = bus; + slot->number = i; + slot->devfn = PCI_DEVFN(i, 0); + + snprintf(name, SLOT_NAME_SIZE, "%02x:%02x", bus->number, i); + + hotplug_slot->private = slot; + hotplug_slot->release = &release_slot; + hotplug_slot->ops = &cpci_hotplug_slot_ops; + + /* + * Initialize the slot info structure with some known + * good values. + */ + dbg("initializing slot %s", name); + info->power_status = cpci_get_power_status(slot); + info->attention_status = cpci_get_attention_status(slot); + + dbg("registering slot %s", name); + status = pci_hp_register(slot->hotplug_slot, bus, i, name); + if (status) { + err("pci_hp_register failed with error %d", status); + goto error_info; + } + dbg("slot registered with name: %s", slot_name(slot)); + + /* Add slot to our internal list */ + down_write(&list_rwsem); + list_add(&slot->slot_list, &slot_list); + slots++; + up_write(&list_rwsem); + } + return 0; +error_info: + kfree(info); +error_hpslot: + kfree(hotplug_slot); +error_slot: + kfree(slot); +error: + return status; +} + +int +cpci_hp_unregister_bus(struct pci_bus *bus) +{ + struct slot *slot; + struct slot *tmp; + int status = 0; + + down_write(&list_rwsem); + if (!slots) { + up_write(&list_rwsem); + return -1; + } + list_for_each_entry_safe(slot, tmp, &slot_list, slot_list) { + if (slot->bus == bus) { + list_del(&slot->slot_list); + slots--; + + dbg("deregistering slot %s", slot_name(slot)); + status = pci_hp_deregister(slot->hotplug_slot); + if (status) { + err("pci_hp_deregister failed with error %d", + status); + break; + } + } + } + up_write(&list_rwsem); + return status; +} + +/* This is the interrupt mode interrupt handler */ +static irqreturn_t +cpci_hp_intr(int irq, void *data) +{ + dbg("entered cpci_hp_intr"); + + /* Check to see if it was our interrupt */ + if ((controller->irq_flags & IRQF_SHARED) && + !controller->ops->check_irq(controller->dev_id)) { + dbg("exited cpci_hp_intr, not our interrupt"); + return IRQ_NONE; + } + + /* Disable ENUM interrupt */ + controller->ops->disable_irq(); + + /* Trigger processing by the event thread */ + wake_up_process(cpci_thread); + return IRQ_HANDLED; +} + +/* + * According to PICMG 2.1 R2.0, section 6.3.2, upon + * initialization, the system driver shall clear the + * INS bits of the cold-inserted devices. + */ +static int +init_slots(int clear_ins) +{ + struct slot *slot; + struct pci_dev* dev; + + dbg("%s - enter", __func__); + down_read(&list_rwsem); + if (!slots) { + up_read(&list_rwsem); + return -1; + } + list_for_each_entry(slot, &slot_list, slot_list) { + dbg("%s - looking at slot %s", __func__, slot_name(slot)); + if (clear_ins && cpci_check_and_clear_ins(slot)) + dbg("%s - cleared INS for slot %s", + __func__, slot_name(slot)); + dev = pci_get_slot(slot->bus, PCI_DEVFN(slot->number, 0)); + if (dev) { + if (update_adapter_status(slot->hotplug_slot, 1)) + warn("failure to update adapter file"); + if (update_latch_status(slot->hotplug_slot, 1)) + warn("failure to update latch file"); + slot->dev = dev; + } + } + up_read(&list_rwsem); + dbg("%s - exit", __func__); + return 0; +} + +static int +check_slots(void) +{ + struct slot *slot; + int extracted; + int inserted; + u16 hs_csr; + + down_read(&list_rwsem); + if (!slots) { + up_read(&list_rwsem); + err("no slots registered, shutting down"); + return -1; + } + extracted = inserted = 0; + list_for_each_entry(slot, &slot_list, slot_list) { + dbg("%s - looking at slot %s", __func__, slot_name(slot)); + if (cpci_check_and_clear_ins(slot)) { + /* + * Some broken hardware (e.g. PLX 9054AB) asserts + * ENUM# twice... + */ + if (slot->dev) { + warn("slot %s already inserted", + slot_name(slot)); + inserted++; + continue; + } + + /* Process insertion */ + dbg("%s - slot %s inserted", __func__, slot_name(slot)); + + /* GSM, debug */ + hs_csr = cpci_get_hs_csr(slot); + dbg("%s - slot %s HS_CSR (1) = %04x", + __func__, slot_name(slot), hs_csr); + + /* Configure device */ + dbg("%s - configuring slot %s", + __func__, slot_name(slot)); + if (cpci_configure_slot(slot)) { + err("%s - could not configure slot %s", + __func__, slot_name(slot)); + continue; + } + dbg("%s - finished configuring slot %s", + __func__, slot_name(slot)); + + /* GSM, debug */ + hs_csr = cpci_get_hs_csr(slot); + dbg("%s - slot %s HS_CSR (2) = %04x", + __func__, slot_name(slot), hs_csr); + + if (update_latch_status(slot->hotplug_slot, 1)) + warn("failure to update latch file"); + + if (update_adapter_status(slot->hotplug_slot, 1)) + warn("failure to update adapter file"); + + cpci_led_off(slot); + + /* GSM, debug */ + hs_csr = cpci_get_hs_csr(slot); + dbg("%s - slot %s HS_CSR (3) = %04x", + __func__, slot_name(slot), hs_csr); + + inserted++; + } else if (cpci_check_ext(slot)) { + /* Process extraction request */ + dbg("%s - slot %s extracted", + __func__, slot_name(slot)); + + /* GSM, debug */ + hs_csr = cpci_get_hs_csr(slot); + dbg("%s - slot %s HS_CSR = %04x", + __func__, slot_name(slot), hs_csr); + + if (!slot->extracting) { + if (update_latch_status(slot->hotplug_slot, 0)) { + warn("failure to update latch file"); + } + slot->extracting = 1; + atomic_inc(&extracting); + } + extracted++; + } else if (slot->extracting) { + hs_csr = cpci_get_hs_csr(slot); + if (hs_csr == 0xffff) { + /* + * Hmmm, we're likely hosed at this point, should we + * bother trying to tell the driver or not? + */ + err("card in slot %s was improperly removed", + slot_name(slot)); + if (update_adapter_status(slot->hotplug_slot, 0)) + warn("failure to update adapter file"); + slot->extracting = 0; + atomic_dec(&extracting); + } + } + } + up_read(&list_rwsem); + dbg("inserted=%d, extracted=%d, extracting=%d", + inserted, extracted, atomic_read(&extracting)); + if (inserted || extracted) + return extracted; + else if (!atomic_read(&extracting)) { + err("cannot find ENUM# source, shutting down"); + return -1; + } + return 0; +} + +/* This is the interrupt mode worker thread body */ +static int +event_thread(void *data) +{ + int rc; + + dbg("%s - event thread started", __func__); + while (1) { + dbg("event thread sleeping"); + set_current_state(TASK_INTERRUPTIBLE); + schedule(); + if (kthread_should_stop()) + break; + do { + rc = check_slots(); + if (rc > 0) { + /* Give userspace a chance to handle extraction */ + msleep(500); + } else if (rc < 0) { + dbg("%s - error checking slots", __func__); + thread_finished = 1; + goto out; + } + } while (atomic_read(&extracting) && !kthread_should_stop()); + if (kthread_should_stop()) + break; + + /* Re-enable ENUM# interrupt */ + dbg("%s - re-enabling irq", __func__); + controller->ops->enable_irq(); + } + out: + return 0; +} + +/* This is the polling mode worker thread body */ +static int +poll_thread(void *data) +{ + int rc; + + while (1) { + if (kthread_should_stop() || signal_pending(current)) + break; + if (controller->ops->query_enum()) { + do { + rc = check_slots(); + if (rc > 0) { + /* Give userspace a chance to handle extraction */ + msleep(500); + } else if (rc < 0) { + dbg("%s - error checking slots", __func__); + thread_finished = 1; + goto out; + } + } while (atomic_read(&extracting) && !kthread_should_stop()); + } + msleep(100); + } + out: + return 0; +} + +static int +cpci_start_thread(void) +{ + if (controller->irq) + cpci_thread = kthread_run(event_thread, NULL, "cpci_hp_eventd"); + else + cpci_thread = kthread_run(poll_thread, NULL, "cpci_hp_polld"); + if (IS_ERR(cpci_thread)) { + err("Can't start up our thread"); + return PTR_ERR(cpci_thread); + } + thread_finished = 0; + return 0; +} + +static void +cpci_stop_thread(void) +{ + kthread_stop(cpci_thread); + thread_finished = 1; +} + +int +cpci_hp_register_controller(struct cpci_hp_controller *new_controller) +{ + int status = 0; + + if (controller) + return -1; + if (!(new_controller && new_controller->ops)) + return -EINVAL; + if (new_controller->irq) { + if (!(new_controller->ops->enable_irq && + new_controller->ops->disable_irq)) + status = -EINVAL; + if (request_irq(new_controller->irq, + cpci_hp_intr, + new_controller->irq_flags, + MY_NAME, + new_controller->dev_id)) { + err("Can't get irq %d for the hotplug cPCI controller", + new_controller->irq); + status = -ENODEV; + } + dbg("%s - acquired controller irq %d", + __func__, new_controller->irq); + } + if (!status) + controller = new_controller; + return status; +} + +static void +cleanup_slots(void) +{ + struct slot *slot; + struct slot *tmp; + + /* + * Unregister all of our slots with the pci_hotplug subsystem, + * and free up all memory that we had allocated. + */ + down_write(&list_rwsem); + if (!slots) + goto cleanup_null; + list_for_each_entry_safe(slot, tmp, &slot_list, slot_list) { + list_del(&slot->slot_list); + pci_hp_deregister(slot->hotplug_slot); + } +cleanup_null: + up_write(&list_rwsem); + return; +} + +int +cpci_hp_unregister_controller(struct cpci_hp_controller *old_controller) +{ + int status = 0; + + if (controller) { + if (!thread_finished) + cpci_stop_thread(); + if (controller->irq) + free_irq(controller->irq, controller->dev_id); + controller = NULL; + cleanup_slots(); + } else + status = -ENODEV; + return status; +} + +int +cpci_hp_start(void) +{ + static int first = 1; + int status; + + dbg("%s - enter", __func__); + if (!controller) + return -ENODEV; + + down_read(&list_rwsem); + if (list_empty(&slot_list)) { + up_read(&list_rwsem); + return -ENODEV; + } + up_read(&list_rwsem); + + status = init_slots(first); + if (first) + first = 0; + if (status) + return status; + + status = cpci_start_thread(); + if (status) + return status; + dbg("%s - thread started", __func__); + + if (controller->irq) { + /* Start enum interrupt processing */ + dbg("%s - enabling irq", __func__); + controller->ops->enable_irq(); + } + dbg("%s - exit", __func__); + return 0; +} + +int +cpci_hp_stop(void) +{ + if (!controller) + return -ENODEV; + if (controller->irq) { + /* Stop enum interrupt processing */ + dbg("%s - disabling irq", __func__); + controller->ops->disable_irq(); + } + cpci_stop_thread(); + return 0; +} + +int __init +cpci_hotplug_init(int debug) +{ + cpci_debug = debug; + return 0; +} + +void __exit +cpci_hotplug_exit(void) +{ + /* + * Clean everything up. + */ + cpci_hp_stop(); + cpci_hp_unregister_controller(controller); +} + +EXPORT_SYMBOL_GPL(cpci_hp_register_controller); +EXPORT_SYMBOL_GPL(cpci_hp_unregister_controller); +EXPORT_SYMBOL_GPL(cpci_hp_register_bus); +EXPORT_SYMBOL_GPL(cpci_hp_unregister_bus); +EXPORT_SYMBOL_GPL(cpci_hp_start); +EXPORT_SYMBOL_GPL(cpci_hp_stop); |