linux/drivers/pci/hotplug/pciehp_core.c
Kenji Kaneshige 8792e11f1c PCI: pciehp: prevent unnecessary power off
Prevent unnecessary power off at initialization time. If slot power
is already off, we don't need to power off the slot.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-11-04 09:02:35 -08:00

385 lines
10 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);
/**
* 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->ops);
kfree(hotplug_slot->info);
kfree(hotplug_slot);
}
static int init_slot(struct controller *ctrl)
{
struct slot *slot = ctrl->slot;
struct hotplug_slot *hotplug = NULL;
struct hotplug_slot_info *info = NULL;
struct hotplug_slot_ops *ops = NULL;
char name[SLOT_NAME_SIZE];
int retval = -ENOMEM;
hotplug = kzalloc(sizeof(*hotplug), GFP_KERNEL);
if (!hotplug)
goto out;
info = kzalloc(sizeof(*info), GFP_KERNEL);
if (!info)
goto out;
/* Setup hotplug slot ops */
ops = kzalloc(sizeof(*ops), GFP_KERNEL);
if (!ops)
goto out;
ops->enable_slot = enable_slot;
ops->disable_slot = disable_slot;
ops->get_power_status = get_power_status;
ops->get_adapter_status = get_adapter_status;
ops->get_max_bus_speed = get_max_bus_speed;
ops->get_cur_bus_speed = get_cur_bus_speed;
if (MRL_SENS(ctrl))
ops->get_latch_status = get_latch_status;
if (ATTN_LED(ctrl)) {
ops->get_attention_status = get_attention_status;
ops->set_attention_status = set_attention_status;
}
/* register this slot with the hotplug pci core */
hotplug->info = info;
hotplug->private = slot;
hotplug->release = &release_slot;
hotplug->ops = ops;
slot->hotplug_slot = hotplug;
snprintf(name, SLOT_NAME_SIZE, "%u", PSN(ctrl));
ctrl_dbg(ctrl, "Registering domain:bus:dev=%04x:%02x:00 sun=%x\n",
pci_domain_nr(ctrl->pcie->port->subordinate),
ctrl->pcie->port->subordinate->number, PSN(ctrl));
retval = pci_hp_register(hotplug,
ctrl->pcie->port->subordinate, 0, name);
if (retval)
ctrl_err(ctrl,
"pci_hp_register failed with error %d\n", retval);
out:
if (retval) {
kfree(ops);
kfree(info);
kfree(hotplug);
}
return retval;
}
static void cleanup_slot(struct controller *ctrl)
{
pci_hp_deregister(ctrl->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));
return pciehp_set_attention_status(slot, status);
}
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;
ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
__func__, slot_name(slot));
return pciehp_get_power_status(slot, value);
}
static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
struct slot *slot = hotplug_slot->private;
ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
__func__, slot_name(slot));
return pciehp_get_attention_status(slot, value);
}
static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
struct slot *slot = hotplug_slot->private;
ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
__func__, slot_name(slot));
return pciehp_get_latch_status(slot, value);
}
static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
struct slot *slot = hotplug_slot->private;
ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
__func__, slot_name(slot));
return pciehp_get_adapter_status(slot, value);
}
static int get_max_bus_speed(struct hotplug_slot *hotplug_slot,
enum pci_bus_speed *value)
{
struct slot *slot = hotplug_slot->private;
ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
__func__, slot_name(slot));
return pciehp_get_max_link_speed(slot, value);
}
static int get_cur_bus_speed(struct hotplug_slot *hotplug_slot, enum pci_bus_speed *value)
{
struct slot *slot = hotplug_slot->private;
ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
__func__, slot_name(slot));
return pciehp_get_cur_link_speed(slot, value);
}
static int pciehp_probe(struct pcie_device *dev)
{
int rc;
struct controller *ctrl;
struct slot *slot;
u8 occupied, poweron;
if (pciehp_force)
dev_info(&dev->device,
"Bypassing BIOS check for pciehp use on %s\n",
pci_name(dev->port));
else if (pciehp_get_hp_hw_control_from_firmware(dev->port))
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_slot(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;
}
/* Enable events after we have setup the data structures */
rc = pcie_init_notification(ctrl);
if (rc) {
ctrl_err(ctrl, "Notification initialization failed\n");
goto err_out_free_ctrl_slot;
}
/* Check if slot is occupied */
slot = ctrl->slot;
pciehp_get_adapter_status(slot, &occupied);
pciehp_get_power_status(slot, &poweron);
if (occupied && pciehp_force)
pciehp_enable_slot(slot);
/* If empty slot's power status is on, turn power off */
if (!occupied && poweron && POWER_CTRL(ctrl))
pciehp_power_off_slot(slot);
return 0;
err_out_free_ctrl_slot:
cleanup_slot(ctrl);
err_out_release_ctlr:
pciehp_release_ctrl(ctrl);
err_out_none:
return -ENODEV;
}
static void pciehp_remove(struct pcie_device *dev)
{
struct controller *ctrl = get_service_data(dev);
cleanup_slot(ctrl);
pciehp_release_ctrl(ctrl);
}
#ifdef CONFIG_PM
static int pciehp_suspend (struct pcie_device *dev)
{
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 *slot;
u8 status;
/* reinitialize the chipset's event detection logic */
pcie_enable_notification(ctrl);
slot = ctrl->slot;
/* Check if slot is occupied */
pciehp_get_adapter_status(slot, &status);
if (status)
pciehp_enable_slot(slot);
else
pciehp_disable_slot(slot);
}
return 0;
}
#endif /* PM */
static struct pcie_port_service_driver hpdriver_portdrv = {
.name = PCIE_MODULE_NAME,
.port_type = PCIE_ANY_PORT,
.service = PCIE_PORT_SERVICE_HP,
.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);