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/* 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>
*
*/
#ifndef _PCIEHP_H
#define _PCIEHP_H
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/pci_hotplug.h>
#include <linux/delay.h>
#include <linux/sched/signal.h> /* signal_pending() */
#include <linux/mutex.h>
#include <linux/rwsem.h>
#include <linux/workqueue.h>
#include "../pcie/portdrv.h"
#define MY_NAME "pciehp"
extern bool pciehp_poll_mode;
extern int pciehp_poll_time;
extern bool pciehp_debug;
#define dbg(format, arg...) \
do { \
if (pciehp_debug) \
printk(KERN_DEBUG "%s: " format, MY_NAME, ## arg); \
} while (0)
#define err(format, arg...) \
printk(KERN_ERR "%s: " format, MY_NAME, ## arg)
#define info(format, arg...) \
printk(KERN_INFO "%s: " format, MY_NAME, ## arg)
#define warn(format, arg...) \
printk(KERN_WARNING "%s: " format, MY_NAME, ## arg)
#define ctrl_dbg(ctrl, format, arg...) \
do { \
if (pciehp_debug) \
dev_printk(KERN_DEBUG, &ctrl->pcie->device, \
format, ## arg); \
} while (0)
#define ctrl_err(ctrl, format, arg...) \
dev_err(&ctrl->pcie->device, format, ## arg)
#define ctrl_info(ctrl, format, arg...) \
dev_info(&ctrl->pcie->device, format, ## arg)
#define ctrl_warn(ctrl, format, arg...) \
dev_warn(&ctrl->pcie->device, format, ## arg)
#define SLOT_NAME_SIZE 10
/**
* struct slot - PCIe hotplug slot
* @state: current state machine position
* @ctrl: pointer to the slot's controller structure
* @hotplug_slot: pointer to the structure registered with the PCI hotplug core
* @work: work item to turn the slot on or off after 5 seconds in response to
* an Attention Button press
* @lock: protects reads and writes of @state;
* protects scheduling, execution and cancellation of @work
*/
struct slot {
u8 state;
struct controller *ctrl;
struct hotplug_slot *hotplug_slot;
struct delayed_work work;
struct mutex lock;
};
/**
* struct controller - PCIe hotplug controller
* @ctrl_lock: serializes writes to the Slot Control register
* @pcie: pointer to the controller's PCIe port service device
* @reset_lock: prevents access to the Data Link Layer Link Active bit in the
* Link Status register and to the Presence Detect State bit in the Slot
* Status register during a slot reset which may cause them to flap
* @slot: pointer to the controller's slot structure
* @queue: wait queue to wake up on reception of a Command Completed event,
* used for synchronous writes to the Slot Control register
* @slot_cap: cached copy of the Slot Capabilities register
* @slot_ctrl: cached copy of the Slot Control register
* @poll_thread: thread to poll for slot events if no IRQ is available,
* enabled with pciehp_poll_mode module parameter
* @cmd_started: jiffies when the Slot Control register was last written;
* the next write is allowed 1 second later, absent a Command Completed
* interrupt (PCIe r4.0, sec 6.7.3.2)
* @cmd_busy: flag set on Slot Control register write, cleared by IRQ handler
* on reception of a Command Completed event
* @link_active_reporting: cached copy of Data Link Layer Link Active Reporting
* Capable bit in Link Capabilities register; if this bit is zero, the
* Data Link Layer Link Active bit in the Link Status register will never
* be set and the driver is thus confined to wait 1 second before assuming
* the link to a hotplugged device is up and accessing it
* @notification_enabled: whether the IRQ was requested successfully
* @power_fault_detected: whether a power fault was detected by the hardware
* that has not yet been cleared by the user
* @pending_events: used by the IRQ handler to save events retrieved from the
* Slot Status register for later consumption by the IRQ thread
* @ist_running: flag to keep user request waiting while IRQ thread is running
* @request_result: result of last user request submitted to the IRQ thread
* @requester: wait queue to wake up on completion of user request,
* used for synchronous slot enable/disable request via sysfs
*/
struct controller {
struct mutex ctrl_lock;
struct pcie_device *pcie;
struct rw_semaphore reset_lock;
struct slot *slot;
wait_queue_head_t queue;
u32 slot_cap;
u16 slot_ctrl;
struct task_struct *poll_thread;
unsigned long cmd_started; /* jiffies */
unsigned int cmd_busy:1;
unsigned int link_active_reporting:1;
unsigned int notification_enabled:1;
unsigned int power_fault_detected;
atomic_t pending_events;
unsigned int ist_running;
int request_result;
wait_queue_head_t requester;
};
/**
* DOC: Slot state
*
* @OFF_STATE: slot is powered off, no subordinate devices are enumerated
* @BLINKINGON_STATE: slot will be powered on after the 5 second delay,
* green led is blinking
* @BLINKINGOFF_STATE: slot will be powered off after the 5 second delay,
* green led is blinking
* @POWERON_STATE: slot is currently powering on
* @POWEROFF_STATE: slot is currently powering off
* @ON_STATE: slot is powered on, subordinate devices have been enumerated
*/
#define OFF_STATE 0
#define BLINKINGON_STATE 1
#define BLINKINGOFF_STATE 2
#define POWERON_STATE 3
#define POWEROFF_STATE 4
#define ON_STATE 5
/**
* DOC: Flags to request an action from the IRQ thread
*
* These are stored together with events read from the Slot Status register,
* hence must be greater than its 16-bit width.
*
* %DISABLE_SLOT: Disable the slot in response to a user request via sysfs or
* an Attention Button press after the 5 second delay
* %RERUN_ISR: Used by the IRQ handler to inform the IRQ thread that the
* hotplug port was inaccessible when the interrupt occurred, requiring
* that the IRQ handler is rerun by the IRQ thread after it has made the
* hotplug port accessible by runtime resuming its parents to D0
*/
#define DISABLE_SLOT (1 << 16)
#define RERUN_ISR (1 << 17)
#define ATTN_BUTTN(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_ABP)
#define POWER_CTRL(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_PCP)
#define MRL_SENS(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_MRLSP)
#define ATTN_LED(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_AIP)
#define PWR_LED(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_PIP)
#define HP_SUPR_RM(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_HPS)
#define EMI(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_EIP)
#define NO_CMD_CMPL(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_NCCS)
#define PSN(ctrl) (((ctrl)->slot_cap & PCI_EXP_SLTCAP_PSN) >> 19)
int pciehp_sysfs_enable_slot(struct slot *slot);
int pciehp_sysfs_disable_slot(struct slot *slot);
void pciehp_request(struct controller *ctrl, int action);
void pciehp_handle_button_press(struct slot *slot);
void pciehp_handle_disable_request(struct slot *slot);
void pciehp_handle_presence_or_link_change(struct slot *slot, u32 events);
int pciehp_configure_device(struct slot *p_slot);
void pciehp_unconfigure_device(struct slot *p_slot);
void pciehp_queue_pushbutton_work(struct work_struct *work);
struct controller *pcie_init(struct pcie_device *dev);
int pcie_init_notification(struct controller *ctrl);
void pcie_shutdown_notification(struct controller *ctrl);
void pcie_clear_hotplug_events(struct controller *ctrl);
int pciehp_power_on_slot(struct slot *slot);
void pciehp_power_off_slot(struct slot *slot);
void pciehp_get_power_status(struct slot *slot, u8 *status);
void pciehp_get_attention_status(struct slot *slot, u8 *status);
void pciehp_set_attention_status(struct slot *slot, u8 status);
void pciehp_get_latch_status(struct slot *slot, u8 *status);
void pciehp_get_adapter_status(struct slot *slot, u8 *status);
int pciehp_query_power_fault(struct slot *slot);
void pciehp_green_led_on(struct slot *slot);
void pciehp_green_led_off(struct slot *slot);
void pciehp_green_led_blink(struct slot *slot);
int pciehp_check_link_status(struct controller *ctrl);
bool pciehp_check_link_active(struct controller *ctrl);
void pciehp_release_ctrl(struct controller *ctrl);
int pciehp_reset_slot(struct slot *slot, int probe);
int pciehp_set_raw_indicator_status(struct hotplug_slot *h_slot, u8 status);
int pciehp_get_raw_indicator_status(struct hotplug_slot *h_slot, u8 *status);
static inline const char *slot_name(struct slot *slot)
{
return hotplug_slot_name(slot->hotplug_slot);
}
#endif /* _PCIEHP_H */