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linux/drivers/pci/hotplug/pciehp_core.c
rajesh.shah@intel.com a3a45ec8f8 [PATCH] pciehp: clean-up how we request control of hotplug hardware
This patch further tweaks how we request control of hotplug
controller hardware from BIOS. We first search the ACPI namespace
corresponding to a specific hotplug controller looking for an
_OSC or OSHP method. On failure, we successively move to the
ACPI parent object, till we hit the highest level host bridge
in the hierarchy. This allows for different types of BIOS's
which place the _OSC/OSHP methods at various places in the acpi
namespace, while still not encroaching on the namespace of
some other root level host bridge.

This patch also introduces a new load time option (pciehp_force)
that allows us to bypass all _OSC/OSHP checking. Not supporting
these methods seems to be be the most common ACPI firmware problem
we've run into. This will still _not_ allow the pciehp driver to
work correctly if the BIOS really doesn't support pciehp (i.e. if
it doesn't generate a hotplug interrupt). Use this option with
caution.  Some BIOS's may deliberately not build any _OSC/OSHP
methods to make sure it retains control the hotplug hardware.
Using the pciehp_force parameter for such systems can lead to
two separate entities trying to control the same hardware.

Signed-off-by: Rajesh Shah <rajesh.shah@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-11-10 16:09:15 -08:00

590 lines
15 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>
/* Global variables */
int pciehp_debug;
int pciehp_poll_mode;
int pciehp_poll_time;
int pciehp_force;
struct controller *pciehp_ctrl_list;
#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 pcie_start_thread (void);
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,
};
/**
* 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;
dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
kfree(slot->hotplug_slot->info);
kfree(slot->hotplug_slot->name);
kfree(slot->hotplug_slot);
kfree(slot);
}
static int init_slots(struct controller *ctrl)
{
struct slot *new_slot;
u8 number_of_slots;
u8 slot_device;
u32 slot_number;
int result = -ENOMEM;
number_of_slots = ctrl->num_slots;
slot_device = ctrl->slot_device_offset;
slot_number = ctrl->first_slot;
while (number_of_slots) {
new_slot = kmalloc(sizeof(*new_slot), GFP_KERNEL);
if (!new_slot)
goto error;
memset(new_slot, 0, sizeof(struct slot));
new_slot->hotplug_slot =
kmalloc(sizeof(*(new_slot->hotplug_slot)),
GFP_KERNEL);
if (!new_slot->hotplug_slot)
goto error_slot;
memset(new_slot->hotplug_slot, 0, sizeof(struct hotplug_slot));
new_slot->hotplug_slot->info =
kmalloc(sizeof(*(new_slot->hotplug_slot->info)),
GFP_KERNEL);
if (!new_slot->hotplug_slot->info)
goto error_hpslot;
memset(new_slot->hotplug_slot->info, 0,
sizeof(struct hotplug_slot_info));
new_slot->hotplug_slot->name = kmalloc(SLOT_NAME_SIZE,
GFP_KERNEL);
if (!new_slot->hotplug_slot->name)
goto error_info;
new_slot->ctrl = ctrl;
new_slot->bus = ctrl->slot_bus;
new_slot->device = slot_device;
new_slot->hpc_ops = ctrl->hpc_ops;
new_slot->number = ctrl->first_slot;
new_slot->hp_slot = slot_device - ctrl->slot_device_offset;
/* register this slot with the hotplug pci core */
new_slot->hotplug_slot->private = new_slot;
new_slot->hotplug_slot->release = &release_slot;
make_slot_name(new_slot->hotplug_slot->name, SLOT_NAME_SIZE, new_slot);
new_slot->hotplug_slot->ops = &pciehp_hotplug_slot_ops;
new_slot->hpc_ops->get_power_status(new_slot, &(new_slot->hotplug_slot->info->power_status));
new_slot->hpc_ops->get_attention_status(new_slot, &(new_slot->hotplug_slot->info->attention_status));
new_slot->hpc_ops->get_latch_status(new_slot, &(new_slot->hotplug_slot->info->latch_status));
new_slot->hpc_ops->get_adapter_status(new_slot, &(new_slot->hotplug_slot->info->adapter_status));
dbg("Registering bus=%x dev=%x hp_slot=%x sun=%x slot_device_offset=%x\n",
new_slot->bus, new_slot->device, new_slot->hp_slot, new_slot->number, ctrl->slot_device_offset);
result = pci_hp_register (new_slot->hotplug_slot);
if (result) {
err ("pci_hp_register failed with error %d\n", result);
goto error_name;
}
new_slot->next = ctrl->slot;
ctrl->slot = new_slot;
number_of_slots--;
slot_device++;
slot_number += ctrl->slot_num_inc;
}
return 0;
error_name:
kfree(new_slot->hotplug_slot->name);
error_info:
kfree(new_slot->hotplug_slot->info);
error_hpslot:
kfree(new_slot->hotplug_slot);
error_slot:
kfree(new_slot);
error:
return result;
}
static int cleanup_slots (struct controller * ctrl)
{
struct slot *old_slot, *next_slot;
old_slot = ctrl->slot;
ctrl->slot = NULL;
while (old_slot) {
next_slot = old_slot->next;
pci_hp_deregister (old_slot->hotplug_slot);
old_slot = next_slot;
}
return(0);
}
static int get_ctlr_slot_config(struct controller *ctrl)
{
int num_ctlr_slots; /* Not needed; PCI Express has 1 slot per port*/
int first_device_num; /* Not needed */
int physical_slot_num;
u8 ctrlcap;
int rc;
rc = pcie_get_ctlr_slot_config(ctrl, &num_ctlr_slots, &first_device_num, &physical_slot_num, &ctrlcap);
if (rc) {
err("%s: get_ctlr_slot_config fail for b:d (%x:%x)\n", __FUNCTION__, ctrl->bus, ctrl->device);
return (-1);
}
ctrl->num_slots = num_ctlr_slots; /* PCI Express has 1 slot per port */
ctrl->slot_device_offset = first_device_num;
ctrl->first_slot = physical_slot_num;
ctrl->ctrlcap = ctrlcap;
dbg("%s: bus(0x%x) num_slot(0x%x) 1st_dev(0x%x) psn(0x%x) ctrlcap(%x) for b:d (%x:%x)\n",
__FUNCTION__, ctrl->slot_bus, num_ctlr_slots, first_device_num, physical_slot_num, ctrlcap,
ctrl->bus, ctrl->device);
return (0);
}
/*
* 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;
dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
hotplug_slot->info->attention_status = status;
if (ATTN_LED(slot->ctrl->ctrlcap))
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;
dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
return pciehp_enable_slot(slot);
}
static int disable_slot(struct hotplug_slot *hotplug_slot)
{
struct slot *slot = hotplug_slot->private;
dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
return pciehp_disable_slot(slot);
}
static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
struct slot *slot = hotplug_slot->private;
int retval;
dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
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;
dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
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;
dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
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;
dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
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;
dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
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;
dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
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;
int first_device_num = 0 ; /* first PCI device number supported by this PCIE */
int num_ctlr_slots; /* number of slots supported by this HPC */
u8 value;
struct pci_dev *pdev;
ctrl = kmalloc(sizeof(*ctrl), GFP_KERNEL);
if (!ctrl) {
err("%s : out of memory\n", __FUNCTION__);
goto err_out_none;
}
memset(ctrl, 0, sizeof(struct controller));
pdev = dev->port;
ctrl->pci_dev = pdev;
rc = pcie_init(ctrl, dev);
if (rc) {
dbg("%s: controller initialization failed\n", PCIE_MODULE_NAME);
goto err_out_free_ctrl;
}
pci_set_drvdata(pdev, ctrl);
ctrl->pci_bus = kmalloc(sizeof(*ctrl->pci_bus), GFP_KERNEL);
if (!ctrl->pci_bus) {
err("%s: out of memory\n", __FUNCTION__);
rc = -ENOMEM;
goto err_out_unmap_mmio_region;
}
memcpy (ctrl->pci_bus, pdev->bus, sizeof (*ctrl->pci_bus));
ctrl->bus = pdev->bus->number; /* ctrl bus */
ctrl->slot_bus = pdev->subordinate->number; /* bus controlled by this HPC */
ctrl->device = PCI_SLOT(pdev->devfn);
ctrl->function = PCI_FUNC(pdev->devfn);
dbg("%s: ctrl bus=0x%x, device=%x, function=%x, irq=%x\n", __FUNCTION__,
ctrl->bus, ctrl->device, ctrl->function, pdev->irq);
/*
* Save configuration headers for this and subordinate PCI buses
*/
rc = get_ctlr_slot_config(ctrl);
if (rc) {
err(msg_initialization_err, rc);
goto err_out_free_ctrl_bus;
}
first_device_num = ctrl->slot_device_offset;
num_ctlr_slots = ctrl->num_slots;
/* Setup the slot information structures */
rc = init_slots(ctrl);
if (rc) {
err(msg_initialization_err, 6);
goto err_out_free_ctrl_slot;
}
t_slot = pciehp_find_slot(ctrl, first_device_num);
/* Finish setting up the hot plug ctrl device */
ctrl->next_event = 0;
if (!pciehp_ctrl_list) {
pciehp_ctrl_list = ctrl;
ctrl->next = NULL;
} else {
ctrl->next = pciehp_ctrl_list;
pciehp_ctrl_list = ctrl;
}
/* Wait for exclusive access to hardware */
down(&ctrl->crit_sect);
t_slot->hpc_ops->get_adapter_status(t_slot, &value); /* Check if slot is occupied */
if ((POWER_CTRL(ctrl->ctrlcap)) && !value) {
rc = t_slot->hpc_ops->power_off_slot(t_slot); /* Power off slot if not occupied*/
if (rc) {
/* Done with exclusive hardware access */
up(&ctrl->crit_sect);
goto err_out_free_ctrl_slot;
} else
/* Wait for the command to complete */
wait_for_ctrl_irq (ctrl);
}
/* Done with exclusive hardware access */
up(&ctrl->crit_sect);
return 0;
err_out_free_ctrl_slot:
cleanup_slots(ctrl);
err_out_free_ctrl_bus:
kfree(ctrl->pci_bus);
err_out_unmap_mmio_region:
ctrl->hpc_ops->release_ctlr(ctrl);
err_out_free_ctrl:
kfree(ctrl);
err_out_none:
return -ENODEV;
}
static int pcie_start_thread(void)
{
int retval = 0;
dbg("Initialize + Start the notification/polling mechanism \n");
retval = pciehp_event_start_thread();
if (retval) {
dbg("pciehp_event_start_thread() failed\n");
return retval;
}
return retval;
}
static void __exit unload_pciehpd(void)
{
struct controller *ctrl;
struct controller *tctrl;
ctrl = pciehp_ctrl_list;
while (ctrl) {
cleanup_slots(ctrl);
kfree (ctrl->pci_bus);
ctrl->hpc_ops->release_ctlr(ctrl);
tctrl = ctrl;
ctrl = ctrl->next;
kfree(tctrl);
}
/* Stop the notification mechanism */
pciehp_event_stop_thread();
}
int hpdriver_context = 0;
static void pciehp_remove (struct pcie_device *device)
{
printk("%s ENTRY\n", __FUNCTION__);
printk("%s -> Call free_irq for irq = %d\n",
__FUNCTION__, device->irq);
free_irq(device->irq, &hpdriver_context);
}
#ifdef CONFIG_PM
static int pciehp_suspend (struct pcie_device *dev, pm_message_t state)
{
printk("%s ENTRY\n", __FUNCTION__);
return 0;
}
static int pciehp_resume (struct pcie_device *dev)
{
printk("%s ENTRY\n", __FUNCTION__);
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 const char device_name[] = "hpdriver";
static struct pcie_port_service_driver hpdriver_portdrv = {
.name = (char *)device_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;
#ifdef CONFIG_HOTPLUG_PCI_PCIE_POLL_EVENT_MODE
pciehp_poll_mode = 1;
#endif
retval = pcie_start_thread();
if (retval)
goto error_hpc_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("%s: Failure to register service\n", __FUNCTION__);
error_hpc_init:
if (retval) {
pciehp_event_stop_thread();
};
return retval;
}
static void __exit pcied_cleanup(void)
{
dbg("unload_pciehpd()\n");
unload_pciehpd();
pcie_port_service_unregister(&hpdriver_portdrv);
info(DRIVER_DESC " version: " DRIVER_VERSION " unloaded\n");
}
module_init(pcied_init);
module_exit(pcied_cleanup);