drivers/pci/hotplug/pciehp.h - linux - Git at Google

 /* 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/mutex.h>
 #include <linux/rwsem.h>
 #include <linux/workqueue.h>

 #include "../pcie/portdrv.h"

 extern bool pciehp_poll_mode;
 extern int pciehp_poll_time;

 /*
  * Set CONFIG_DYNAMIC_DEBUG=y and boot with 'dyndbg="file pciehp* +p"' to
  * enable debug messages.
  */
 #define ctrl_dbg(ctrl, format, arg...)					\
 	pci_dbg(ctrl->pcie->port, format, ## arg)
 #define ctrl_err(ctrl, format, arg...)					\
 	pci_err(ctrl->pcie->port, format, ## arg)
 #define ctrl_info(ctrl, format, arg...)					\
 	pci_info(ctrl->pcie->port, format, ## arg)
 #define ctrl_warn(ctrl, format, arg...)					\
 	pci_warn(ctrl->pcie->port, format, ## arg)

 #define SLOT_NAME_SIZE 10

 /**
  * struct controller - PCIe hotplug controller
  * @pcie: pointer to the controller's PCIe port service device
  * @slot_cap: cached copy of the Slot Capabilities register
  * @inband_presence_disabled: In-Band Presence Detect Disable supported by
  *	controller and disabled per spec recommendation (PCIe r5.0, appendix I
  *	implementation note)
  * @slot_ctrl: cached copy of the Slot Control register
  * @ctrl_lock: serializes writes to the Slot Control register
  * @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
  * @queue: wait queue to wake up on reception of a Command Completed event,
  *	used for synchronous writes to the Slot Control register
  * @pending_events: used by the IRQ handler to save events retrieved from the
  *	Slot Status register for later consumption by the IRQ thread
  * @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
  * @poll_thread: thread to poll for slot events if no IRQ is available,
  *	enabled with pciehp_poll_mode module parameter
  * @state: current state machine position
  * @state_lock: protects reads and writes of @state;
  *	protects scheduling, execution and cancellation of @button_work
  * @button_work: work item to turn the slot on or off after 5 seconds
  *	in response to an Attention Button press
  * @hotplug_slot: structure registered with the PCI hotplug core
  * @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
  * @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
  *
  * PCIe hotplug has a 1:1 relationship between controller and slot, hence
  * unlike other drivers, the two aren't represented by separate structures.
  */
 struct controller {
 	struct pcie_device *pcie;

 	u32 slot_cap;				/* capabilities and quirks */
 	unsigned int inband_presence_disabled:1;

 	u16 slot_ctrl;				/* control register access */
 	struct mutex ctrl_lock;
 	unsigned long cmd_started;
 	unsigned int cmd_busy:1;
 	wait_queue_head_t queue;

 	atomic_t pending_events;		/* event handling */
 	unsigned int notification_enabled:1;
 	unsigned int power_fault_detected;
 	struct task_struct *poll_thread;

 	u8 state;				/* state machine */
 	struct mutex state_lock;
 	struct delayed_work button_work;

 	struct hotplug_slot hotplug_slot;	/* hotplug core interface */
 	struct rw_semaphore reset_lock;
 	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,
  *	Power Indicator is blinking
  * @BLINKINGOFF_STATE: slot will be powered off after the 5 second delay,
  *	Power Indicator 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 NO_CMD_CMPL(ctrl)	((ctrl)->slot_cap & PCI_EXP_SLTCAP_NCCS)
 #define PSN(ctrl)		(((ctrl)->slot_cap & PCI_EXP_SLTCAP_PSN) >> 19)

 void pciehp_request(struct controller *ctrl, int action);
 void pciehp_handle_button_press(struct controller *ctrl);
 void pciehp_handle_disable_request(struct controller *ctrl);
 void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events);
 int pciehp_configure_device(struct controller *ctrl);
 void pciehp_unconfigure_device(struct controller *ctrl, bool presence);
 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);
 void pcie_enable_interrupt(struct controller *ctrl);
 void pcie_disable_interrupt(struct controller *ctrl);
 int pciehp_power_on_slot(struct controller *ctrl);
 void pciehp_power_off_slot(struct controller *ctrl);
 void pciehp_get_power_status(struct controller *ctrl, u8 *status);

 #define INDICATOR_NOOP -1	/* Leave indicator unchanged */
 void pciehp_set_indicators(struct controller *ctrl, int pwr, int attn);

 void pciehp_get_latch_status(struct controller *ctrl, u8 *status);
 int pciehp_query_power_fault(struct controller *ctrl);
 int pciehp_card_present(struct controller *ctrl);
 int pciehp_card_present_or_link_active(struct controller *ctrl);
 int pciehp_check_link_status(struct controller *ctrl);
 int pciehp_check_link_active(struct controller *ctrl);
 void pciehp_release_ctrl(struct controller *ctrl);

 int pciehp_sysfs_enable_slot(struct hotplug_slot *hotplug_slot);
 int pciehp_sysfs_disable_slot(struct hotplug_slot *hotplug_slot);
 int pciehp_reset_slot(struct hotplug_slot *hotplug_slot, bool probe);
 int pciehp_get_attention_status(struct hotplug_slot *hotplug_slot, u8 *status);
 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 controller *ctrl)
 {
 	return hotplug_slot_name(&ctrl->hotplug_slot);
 }

 static inline struct controller *to_ctrl(struct hotplug_slot *hotplug_slot)
 {
 	return container_of(hotplug_slot, struct controller, hotplug_slot);
 }

 #endif				/* _PCIEHP_H */
	/* 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/mutex.h>
	#include <linux/rwsem.h>
	#include <linux/workqueue.h>

	#include "../pcie/portdrv.h"

	extern bool pciehp_poll_mode;
	extern int pciehp_poll_time;

	/*
	* Set CONFIG_DYNAMIC_DEBUG=y and boot with 'dyndbg="file pciehp* +p"' to
	* enable debug messages.
	*/
	#define ctrl_dbg(ctrl, format, arg...) \
	pci_dbg(ctrl->pcie->port, format, ## arg)
	#define ctrl_err(ctrl, format, arg...) \
	pci_err(ctrl->pcie->port, format, ## arg)
	#define ctrl_info(ctrl, format, arg...) \
	pci_info(ctrl->pcie->port, format, ## arg)
	#define ctrl_warn(ctrl, format, arg...) \
	pci_warn(ctrl->pcie->port, format, ## arg)

	#define SLOT_NAME_SIZE 10

	/**
	* struct controller - PCIe hotplug controller
	* @pcie: pointer to the controller's PCIe port service device
	* @slot_cap: cached copy of the Slot Capabilities register
	* @inband_presence_disabled: In-Band Presence Detect Disable supported by
	* controller and disabled per spec recommendation (PCIe r5.0, appendix I
	* implementation note)
	* @slot_ctrl: cached copy of the Slot Control register
	* @ctrl_lock: serializes writes to the Slot Control register
	* @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
	* @queue: wait queue to wake up on reception of a Command Completed event,
	* used for synchronous writes to the Slot Control register
	* @pending_events: used by the IRQ handler to save events retrieved from the
	* Slot Status register for later consumption by the IRQ thread
	* @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
	* @poll_thread: thread to poll for slot events if no IRQ is available,
	* enabled with pciehp_poll_mode module parameter
	* @state: current state machine position
	* @state_lock: protects reads and writes of @state;
	* protects scheduling, execution and cancellation of @button_work
	* @button_work: work item to turn the slot on or off after 5 seconds
	* in response to an Attention Button press
	* @hotplug_slot: structure registered with the PCI hotplug core
	* @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
	* @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
	*
	* PCIe hotplug has a 1:1 relationship between controller and slot, hence
	* unlike other drivers, the two aren't represented by separate structures.
	*/
	struct controller {
	struct pcie_device *pcie;

	u32 slot_cap; /* capabilities and quirks */
	unsigned int inband_presence_disabled:1;

	u16 slot_ctrl; /* control register access */
	struct mutex ctrl_lock;
	unsigned long cmd_started;
	unsigned int cmd_busy:1;
	wait_queue_head_t queue;

	atomic_t pending_events; /* event handling */
	unsigned int notification_enabled:1;
	unsigned int power_fault_detected;
	struct task_struct *poll_thread;

	u8 state; /* state machine */
	struct mutex state_lock;
	struct delayed_work button_work;

	struct hotplug_slot hotplug_slot; /* hotplug core interface */
	struct rw_semaphore reset_lock;
	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,
	* Power Indicator is blinking
	* @BLINKINGOFF_STATE: slot will be powered off after the 5 second delay,
	* Power Indicator 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 NO_CMD_CMPL(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_NCCS)
	#define PSN(ctrl) (((ctrl)->slot_cap & PCI_EXP_SLTCAP_PSN) >> 19)

	void pciehp_request(struct controller *ctrl, int action);
	void pciehp_handle_button_press(struct controller *ctrl);
	void pciehp_handle_disable_request(struct controller *ctrl);
	void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events);
	int pciehp_configure_device(struct controller *ctrl);
	void pciehp_unconfigure_device(struct controller *ctrl, bool presence);
	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);
	void pcie_enable_interrupt(struct controller *ctrl);
	void pcie_disable_interrupt(struct controller *ctrl);
	int pciehp_power_on_slot(struct controller *ctrl);
	void pciehp_power_off_slot(struct controller *ctrl);
	void pciehp_get_power_status(struct controller ctrl, u8 status);

	#define INDICATOR_NOOP -1 /* Leave indicator unchanged */
	void pciehp_set_indicators(struct controller *ctrl, int pwr, int attn);

	void pciehp_get_latch_status(struct controller ctrl, u8 status);
	int pciehp_query_power_fault(struct controller *ctrl);
	int pciehp_card_present(struct controller *ctrl);
	int pciehp_card_present_or_link_active(struct controller *ctrl);
	int pciehp_check_link_status(struct controller *ctrl);
	int pciehp_check_link_active(struct controller *ctrl);
	void pciehp_release_ctrl(struct controller *ctrl);

	int pciehp_sysfs_enable_slot(struct hotplug_slot *hotplug_slot);
	int pciehp_sysfs_disable_slot(struct hotplug_slot *hotplug_slot);
	int pciehp_reset_slot(struct hotplug_slot *hotplug_slot, bool probe);
	int pciehp_get_attention_status(struct hotplug_slot hotplug_slot, u8 status);
	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 controller ctrl)
	{
	return hotplug_slot_name(&ctrl->hotplug_slot);
	}

	static inline struct controller to_ctrl(struct hotplug_slot hotplug_slot)
	{
	return container_of(hotplug_slot, struct controller, hotplug_slot);
	}

	#endif /* _PCIEHP_H */