linux/drivers/pci/hotplug/pciehp_core.c
Kenji Kaneshige c9ffa5a586 PCI: pciehp: add ACPI based slot detection
There is a problem that some non hot-pluggable PCIe slots are detected
as hot-pluggable by pciehp on some platforms. The immediate cause of
this problem is that hot-plug capable bit in the Slot Capabilities
register is set even for non hot-pluggable slots on those platforms.
It seems a BIOS/hardware problem, but we need workaround about that.

Some of those platforms define hot-pluggable PCIe slots on ACPI
namespace properly, while hot-plug capable bit in the Slot
Capabilities register is set improperly. So using ACPI namespace
information in pciehp to detect PCIe hot-pluggable slots would be a
workaround.

This patch adds 'pciehp_detect_mode' module option. When 'acpi' is
specified, pciehp uses ACPI namespace information to detect PCIe
hot-pluggable slots.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-01-07 11:13:10 -08:00

543 lines
14 KiB
C

/*
* PCI Express Hot Plug Controller Driver
*
* Copyright (C) 1995,2001 Compaq Computer Corporation
* Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
* Copyright (C) 2001 IBM Corp.
* Copyright (C) 2003-2004 Intel Corporation
*
* 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 <greg@kroah.com>, <kristen.c.accardi@intel.com>
*
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/pci.h>
#include "pciehp.h"
#include <linux/interrupt.h>
#include <linux/time.h>
/* Global variables */
int pciehp_debug;
int pciehp_poll_mode;
int pciehp_poll_time;
int pciehp_force;
struct workqueue_struct *pciehp_wq;
#define DRIVER_VERSION "0.4"
#define DRIVER_AUTHOR "Dan Zink <dan.zink@compaq.com>, Greg Kroah-Hartman <greg@kroah.com>, Dely Sy <dely.l.sy@intel.com>"
#define DRIVER_DESC "PCI Express Hot Plug Controller Driver"
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
module_param(pciehp_debug, bool, 0644);
module_param(pciehp_poll_mode, bool, 0644);
module_param(pciehp_poll_time, int, 0644);
module_param(pciehp_force, bool, 0644);
MODULE_PARM_DESC(pciehp_debug, "Debugging mode enabled or not");
MODULE_PARM_DESC(pciehp_poll_mode, "Using polling mechanism for hot-plug events or not");
MODULE_PARM_DESC(pciehp_poll_time, "Polling mechanism frequency, in seconds");
MODULE_PARM_DESC(pciehp_force, "Force pciehp, even if _OSC and OSHP are missing");
#define PCIE_MODULE_NAME "pciehp"
static int set_attention_status (struct hotplug_slot *slot, u8 value);
static int enable_slot (struct hotplug_slot *slot);
static int disable_slot (struct hotplug_slot *slot);
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_latch_status (struct hotplug_slot *slot, u8 *value);
static int get_adapter_status (struct hotplug_slot *slot, u8 *value);
static int get_max_bus_speed (struct hotplug_slot *slot, enum pci_bus_speed *value);
static int get_cur_bus_speed (struct hotplug_slot *slot, enum pci_bus_speed *value);
static struct hotplug_slot_ops pciehp_hotplug_slot_ops = {
.owner = THIS_MODULE,
.set_attention_status = set_attention_status,
.enable_slot = enable_slot,
.disable_slot = disable_slot,
.get_power_status = get_power_status,
.get_attention_status = get_attention_status,
.get_latch_status = get_latch_status,
.get_adapter_status = get_adapter_status,
.get_max_bus_speed = get_max_bus_speed,
.get_cur_bus_speed = get_cur_bus_speed,
};
/*
* Check the status of the Electro Mechanical Interlock (EMI)
*/
static int get_lock_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
struct slot *slot = hotplug_slot->private;
return (slot->hpc_ops->get_emi_status(slot, value));
}
/*
* sysfs interface for the Electro Mechanical Interlock (EMI)
* 1 == locked, 0 == unlocked
*/
static ssize_t lock_read_file(struct hotplug_slot *slot, char *buf)
{
int retval;
u8 value;
retval = get_lock_status(slot, &value);
if (retval)
goto lock_read_exit;
retval = sprintf (buf, "%d\n", value);
lock_read_exit:
return retval;
}
/*
* Change the status of the Electro Mechanical Interlock (EMI)
* This is a toggle - in addition there must be at least 1 second
* in between toggles.
*/
static int set_lock_status(struct hotplug_slot *hotplug_slot, u8 status)
{
struct slot *slot = hotplug_slot->private;
int retval;
u8 value;
mutex_lock(&slot->ctrl->crit_sect);
/* has it been >1 sec since our last toggle? */
if ((get_seconds() - slot->last_emi_toggle) < 1)
return -EINVAL;
/* see what our current state is */
retval = get_lock_status(hotplug_slot, &value);
if (retval || (value == status))
goto set_lock_exit;
slot->hpc_ops->toggle_emi(slot);
set_lock_exit:
mutex_unlock(&slot->ctrl->crit_sect);
return 0;
}
/*
* sysfs interface which allows the user to toggle the Electro Mechanical
* Interlock. Valid values are either 0 or 1. 0 == unlock, 1 == lock
*/
static ssize_t lock_write_file(struct hotplug_slot *hotplug_slot,
const char *buf, size_t count)
{
struct slot *slot = hotplug_slot->private;
unsigned long llock;
u8 lock;
int retval = 0;
llock = simple_strtoul(buf, NULL, 10);
lock = (u8)(llock & 0xff);
switch (lock) {
case 0:
case 1:
retval = set_lock_status(hotplug_slot, lock);
break;
default:
ctrl_err(slot->ctrl, "%d is an invalid lock value\n",
lock);
retval = -EINVAL;
}
if (retval)
return retval;
return count;
}
static struct hotplug_slot_attribute hotplug_slot_attr_lock = {
.attr = {.name = "lock", .mode = S_IFREG | S_IRUGO | S_IWUSR},
.show = lock_read_file,
.store = lock_write_file
};
/**
* release_slot - free up the memory used by a slot
* @hotplug_slot: slot to free
*/
static void release_slot(struct hotplug_slot *hotplug_slot)
{
struct slot *slot = hotplug_slot->private;
ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
__func__, hotplug_slot_name(hotplug_slot));
kfree(hotplug_slot->info);
kfree(hotplug_slot);
}
static int init_slots(struct controller *ctrl)
{
struct slot *slot;
struct hotplug_slot *hotplug_slot;
struct hotplug_slot_info *info;
char name[SLOT_NAME_SIZE];
int retval = -ENOMEM;
list_for_each_entry(slot, &ctrl->slot_list, slot_list) {
hotplug_slot = kzalloc(sizeof(*hotplug_slot), GFP_KERNEL);
if (!hotplug_slot)
goto error;
info = kzalloc(sizeof(*info), GFP_KERNEL);
if (!info)
goto error_hpslot;
/* register this slot with the hotplug pci core */
hotplug_slot->info = info;
hotplug_slot->private = slot;
hotplug_slot->release = &release_slot;
hotplug_slot->ops = &pciehp_hotplug_slot_ops;
slot->hotplug_slot = hotplug_slot;
snprintf(name, SLOT_NAME_SIZE, "%u", slot->number);
ctrl_dbg(ctrl, "Registering domain:bus:dev=%04x:%02x:%02x "
"hp_slot=%x sun=%x slot_device_offset=%x\n",
pci_domain_nr(ctrl->pci_dev->subordinate),
slot->bus, slot->device, slot->hp_slot, slot->number,
ctrl->slot_device_offset);
retval = pci_hp_register(hotplug_slot,
ctrl->pci_dev->subordinate,
slot->device,
name);
if (retval) {
ctrl_err(ctrl, "pci_hp_register failed with error %d\n",
retval);
goto error_info;
}
get_power_status(hotplug_slot, &info->power_status);
get_attention_status(hotplug_slot, &info->attention_status);
get_latch_status(hotplug_slot, &info->latch_status);
get_adapter_status(hotplug_slot, &info->adapter_status);
/* create additional sysfs entries */
if (EMI(ctrl)) {
retval = sysfs_create_file(&hotplug_slot->pci_slot->kobj,
&hotplug_slot_attr_lock.attr);
if (retval) {
pci_hp_deregister(hotplug_slot);
ctrl_err(ctrl, "Cannot create additional sysfs "
"entries\n");
goto error_info;
}
}
}
return 0;
error_info:
kfree(info);
error_hpslot:
kfree(hotplug_slot);
error:
return retval;
}
static void cleanup_slots(struct controller *ctrl)
{
struct slot *slot;
list_for_each_entry(slot, &ctrl->slot_list, slot_list) {
if (EMI(ctrl))
sysfs_remove_file(&slot->hotplug_slot->pci_slot->kobj,
&hotplug_slot_attr_lock.attr);
pci_hp_deregister(slot->hotplug_slot);
}
}
/*
* set_attention_status - Turns the Amber LED for a slot on, off or blink
*/
static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
{
struct slot *slot = hotplug_slot->private;
ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
__func__, slot_name(slot));
hotplug_slot->info->attention_status = status;
if (ATTN_LED(slot->ctrl))
slot->hpc_ops->set_attention_status(slot, status);
return 0;
}
static int enable_slot(struct hotplug_slot *hotplug_slot)
{
struct slot *slot = hotplug_slot->private;
ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
__func__, slot_name(slot));
return pciehp_sysfs_enable_slot(slot);
}
static int disable_slot(struct hotplug_slot *hotplug_slot)
{
struct slot *slot = hotplug_slot->private;
ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
__func__, slot_name(slot));
return pciehp_sysfs_disable_slot(slot);
}
static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
struct slot *slot = hotplug_slot->private;
int retval;
ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
__func__, slot_name(slot));
retval = slot->hpc_ops->get_power_status(slot, value);
if (retval < 0)
*value = hotplug_slot->info->power_status;
return 0;
}
static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
struct slot *slot = hotplug_slot->private;
int retval;
ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
__func__, slot_name(slot));
retval = slot->hpc_ops->get_attention_status(slot, value);
if (retval < 0)
*value = hotplug_slot->info->attention_status;
return 0;
}
static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
struct slot *slot = hotplug_slot->private;
int retval;
ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
__func__, slot_name(slot));
retval = slot->hpc_ops->get_latch_status(slot, value);
if (retval < 0)
*value = hotplug_slot->info->latch_status;
return 0;
}
static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
struct slot *slot = hotplug_slot->private;
int retval;
ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
__func__, slot_name(slot));
retval = slot->hpc_ops->get_adapter_status(slot, value);
if (retval < 0)
*value = hotplug_slot->info->adapter_status;
return 0;
}
static int get_max_bus_speed(struct hotplug_slot *hotplug_slot,
enum pci_bus_speed *value)
{
struct slot *slot = hotplug_slot->private;
int retval;
ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
__func__, slot_name(slot));
retval = slot->hpc_ops->get_max_bus_speed(slot, value);
if (retval < 0)
*value = PCI_SPEED_UNKNOWN;
return 0;
}
static int get_cur_bus_speed(struct hotplug_slot *hotplug_slot, enum pci_bus_speed *value)
{
struct slot *slot = hotplug_slot->private;
int retval;
ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
__func__, slot_name(slot));
retval = slot->hpc_ops->get_cur_bus_speed(slot, value);
if (retval < 0)
*value = PCI_SPEED_UNKNOWN;
return 0;
}
static int pciehp_probe(struct pcie_device *dev, const struct pcie_port_service_id *id)
{
int rc;
struct controller *ctrl;
struct slot *t_slot;
u8 value;
struct pci_dev *pdev = dev->port;
if (pciehp_force)
dev_info(&dev->device,
"Bypassing BIOS check for pciehp use on %s\n",
pci_name(pdev));
else if (pciehp_get_hp_hw_control_from_firmware(pdev))
goto err_out_none;
ctrl = pcie_init(dev);
if (!ctrl) {
dev_err(&dev->device, "Controller initialization failed\n");
goto err_out_none;
}
set_service_data(dev, ctrl);
/* Setup the slot information structures */
rc = init_slots(ctrl);
if (rc) {
if (rc == -EBUSY)
ctrl_warn(ctrl, "Slot already registered by another "
"hotplug driver\n");
else
ctrl_err(ctrl, "Slot initialization failed\n");
goto err_out_release_ctlr;
}
/* Check if slot is occupied */
t_slot = pciehp_find_slot(ctrl, ctrl->slot_device_offset);
t_slot->hpc_ops->get_adapter_status(t_slot, &value);
if (value) {
if (pciehp_force)
pciehp_enable_slot(t_slot);
} else {
/* Power off slot if not occupied */
if (POWER_CTRL(ctrl)) {
rc = t_slot->hpc_ops->power_off_slot(t_slot);
if (rc)
goto err_out_free_ctrl_slot;
}
}
return 0;
err_out_free_ctrl_slot:
cleanup_slots(ctrl);
err_out_release_ctlr:
ctrl->hpc_ops->release_ctlr(ctrl);
err_out_none:
return -ENODEV;
}
static void pciehp_remove (struct pcie_device *dev)
{
struct controller *ctrl = get_service_data(dev);
cleanup_slots(ctrl);
ctrl->hpc_ops->release_ctlr(ctrl);
}
#ifdef CONFIG_PM
static int pciehp_suspend (struct pcie_device *dev, pm_message_t state)
{
dev_info(&dev->device, "%s ENTRY\n", __func__);
return 0;
}
static int pciehp_resume (struct pcie_device *dev)
{
dev_info(&dev->device, "%s ENTRY\n", __func__);
if (pciehp_force) {
struct controller *ctrl = get_service_data(dev);
struct slot *t_slot;
u8 status;
/* reinitialize the chipset's event detection logic */
pcie_enable_notification(ctrl);
t_slot = pciehp_find_slot(ctrl, ctrl->slot_device_offset);
/* Check if slot is occupied */
t_slot->hpc_ops->get_adapter_status(t_slot, &status);
if (status)
pciehp_enable_slot(t_slot);
else
pciehp_disable_slot(t_slot);
}
return 0;
}
#endif
static struct pcie_port_service_id port_pci_ids[] = { {
.vendor = PCI_ANY_ID,
.device = PCI_ANY_ID,
.port_type = PCIE_ANY_PORT,
.service_type = PCIE_PORT_SERVICE_HP,
.driver_data = 0,
}, { /* end: all zeroes */ }
};
static struct pcie_port_service_driver hpdriver_portdrv = {
.name = PCIE_MODULE_NAME,
.id_table = &port_pci_ids[0],
.probe = pciehp_probe,
.remove = pciehp_remove,
#ifdef CONFIG_PM
.suspend = pciehp_suspend,
.resume = pciehp_resume,
#endif /* PM */
};
static int __init pcied_init(void)
{
int retval = 0;
pciehp_firmware_init();
retval = pcie_port_service_register(&hpdriver_portdrv);
dbg("pcie_port_service_register = %d\n", retval);
info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
if (retval)
dbg("Failure to register service\n");
return retval;
}
static void __exit pcied_cleanup(void)
{
dbg("unload_pciehpd()\n");
pcie_port_service_unregister(&hpdriver_portdrv);
info(DRIVER_DESC " version: " DRIVER_VERSION " unloaded\n");
}
module_init(pcied_init);
module_exit(pcied_cleanup);