OpenCloudOS-Kernel/drivers/pci/hotplug/pciehp_core.c

363 lines
9.3 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* 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.
*
* Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
*
* Authors:
* Dan Zink <dan.zink@compaq.com>
* Greg Kroah-Hartman <greg@kroah.com>
* Dely Sy <dely.l.sy@intel.com>"
*/
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/pci.h>
#include "pciehp.h"
#include <linux/interrupt.h>
#include <linux/time.h>
#include "../pci.h"
/* Global variables */
bool pciehp_debug;
bool pciehp_poll_mode;
int pciehp_poll_time;
/*
* not really modular, but the easiest way to keep compat with existing
* bootargs behaviour is to continue using module_param here.
*/
module_param(pciehp_debug, bool, 0644);
module_param(pciehp_poll_mode, bool, 0644);
module_param(pciehp_poll_time, int, 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");
#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 reset_slot(struct hotplug_slot *slot, int probe);
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->reset_slot = reset_slot;
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;
} else if (ctrl->pcie->port->hotplug_user_indicators) {
ops->get_attention_status = pciehp_get_raw_indicator_status;
ops->set_attention_status = pciehp_set_raw_indicator_status;
}
/* register this slot with the hotplug pci core */
hotplug->info = info;
hotplug->private = slot;
hotplug->ops = ops;
slot->hotplug_slot = hotplug;
snprintf(name, SLOT_NAME_SIZE, "%u", PSN(ctrl));
retval = pci_hp_initialize(hotplug,
ctrl->pcie->port->subordinate, 0, name);
if (retval)
ctrl_err(ctrl, "pci_hp_initialize failed: error %d\n", retval);
out:
if (retval) {
kfree(ops);
kfree(info);
kfree(hotplug);
}
return retval;
}
static void cleanup_slot(struct controller *ctrl)
{
struct hotplug_slot *hotplug_slot = ctrl->slot->hotplug_slot;
pci_hp_destroy(hotplug_slot);
kfree(hotplug_slot->ops);
kfree(hotplug_slot->info);
kfree(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;
struct pci_dev *pdev = slot->ctrl->pcie->port;
pci_config_pm_runtime_get(pdev);
pciehp_set_attention_status(slot, status);
pci_config_pm_runtime_put(pdev);
return 0;
}
static int enable_slot(struct hotplug_slot *hotplug_slot)
{
struct slot *slot = hotplug_slot->private;
return pciehp_sysfs_enable_slot(slot);
}
static int disable_slot(struct hotplug_slot *hotplug_slot)
{
struct slot *slot = hotplug_slot->private;
return pciehp_sysfs_disable_slot(slot);
}
static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
struct slot *slot = hotplug_slot->private;
struct pci_dev *pdev = slot->ctrl->pcie->port;
pci_config_pm_runtime_get(pdev);
pciehp_get_power_status(slot, value);
pci_config_pm_runtime_put(pdev);
return 0;
}
static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
struct slot *slot = hotplug_slot->private;
pciehp_get_attention_status(slot, value);
return 0;
}
static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
struct slot *slot = hotplug_slot->private;
struct pci_dev *pdev = slot->ctrl->pcie->port;
pci_config_pm_runtime_get(pdev);
pciehp_get_latch_status(slot, value);
pci_config_pm_runtime_put(pdev);
return 0;
}
static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
struct slot *slot = hotplug_slot->private;
struct pci_dev *pdev = slot->ctrl->pcie->port;
pci_config_pm_runtime_get(pdev);
pciehp_get_adapter_status(slot, value);
pci_config_pm_runtime_put(pdev);
return 0;
}
static int reset_slot(struct hotplug_slot *hotplug_slot, int probe)
{
struct slot *slot = hotplug_slot->private;
return pciehp_reset_slot(slot, probe);
}
/**
* pciehp_check_presence() - synthesize event if presence has changed
*
* On probe and resume, an explicit presence check is necessary to bring up an
* occupied slot or bring down an unoccupied slot. This can't be triggered by
* events in the Slot Status register, they may be stale and are therefore
* cleared. Secondly, sending an interrupt for "events that occur while
* interrupt generation is disabled [when] interrupt generation is subsequently
* enabled" is optional per PCIe r4.0, sec 6.7.3.4.
*/
static void pciehp_check_presence(struct controller *ctrl)
{
struct slot *slot = ctrl->slot;
u8 occupied;
down_read(&ctrl->reset_lock);
mutex_lock(&slot->lock);
pciehp_get_adapter_status(slot, &occupied);
if ((occupied && (slot->state == OFF_STATE ||
slot->state == BLINKINGON_STATE)) ||
(!occupied && (slot->state == ON_STATE ||
slot->state == BLINKINGOFF_STATE)))
pciehp_request(ctrl, PCI_EXP_SLTSTA_PDC);
mutex_unlock(&slot->lock);
up_read(&ctrl->reset_lock);
}
static int pciehp_probe(struct pcie_device *dev)
{
int rc;
struct controller *ctrl;
struct slot *slot;
/* If this is not a "hotplug" service, we have no business here. */
if (dev->service != PCIE_PORT_SERVICE_HP)
return -ENODEV;
if (!dev->port->subordinate) {
/* Can happen if we run out of bus numbers during probe */
dev_err(&dev->device,
"Hotplug bridge without secondary bus, ignoring\n");
return -ENODEV;
}
ctrl = pcie_init(dev);
if (!ctrl) {
dev_err(&dev->device, "Controller initialization failed\n");
return -ENODEV;
}
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 (%d)\n", rc);
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 (%d)\n", rc);
goto err_out_free_ctrl_slot;
}
/* Publish to user space */
slot = ctrl->slot;
rc = pci_hp_add(slot->hotplug_slot);
if (rc) {
ctrl_err(ctrl, "Publication to user space failed (%d)\n", rc);
goto err_out_shutdown_notification;
}
pciehp_check_presence(ctrl);
return 0;
err_out_shutdown_notification:
pcie_shutdown_notification(ctrl);
err_out_free_ctrl_slot:
cleanup_slot(ctrl);
err_out_release_ctlr:
pciehp_release_ctrl(ctrl);
return -ENODEV;
}
static void pciehp_remove(struct pcie_device *dev)
{
struct controller *ctrl = get_service_data(dev);
pci_hp_del(ctrl->slot->hotplug_slot);
pcie_shutdown_notification(ctrl);
cleanup_slot(ctrl);
pciehp_release_ctrl(ctrl);
}
#ifdef CONFIG_PM
static int pciehp_suspend(struct pcie_device *dev)
{
return 0;
}
static int pciehp_resume_noirq(struct pcie_device *dev)
{
struct controller *ctrl = get_service_data(dev);
struct slot *slot = ctrl->slot;
/* pci_restore_state() just wrote to the Slot Control register */
ctrl->cmd_started = jiffies;
ctrl->cmd_busy = true;
/* clear spurious events from rediscovery of inserted card */
if (slot->state == ON_STATE || slot->state == BLINKINGOFF_STATE)
pcie_clear_hotplug_events(ctrl);
return 0;
}
static int pciehp_resume(struct pcie_device *dev)
{
struct controller *ctrl = get_service_data(dev);
pciehp_check_presence(ctrl);
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_noirq = pciehp_resume_noirq,
.resume = pciehp_resume,
#endif /* PM */
};
static int __init pcied_init(void)
{
int retval = 0;
retval = pcie_port_service_register(&hpdriver_portdrv);
dbg("pcie_port_service_register = %d\n", retval);
if (retval)
dbg("Failure to register service\n");
return retval;
}
device_initcall(pcied_init);