LXR linux/drivers/pci/hotplug/pciehp.h

   1/* SPDX-License-Identifier: GPL-2.0+ */
   2/*
   3 * PCI Express Hot Plug Controller Driver
   4 *
   5 * Copyright (C) 1995,2001 Compaq Computer Corporation
   6 * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
   7 * Copyright (C) 2001 IBM Corp.
   8 * Copyright (C) 2003-2004 Intel Corporation
   9 *
  10 * All rights reserved.
  11 *
  12 * Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
  13 *
  14 */
  15#ifndef _PCIEHP_H
  16#define _PCIEHP_H
  17
  18#include <linux/types.h>
  19#include <linux/pci.h>
  20#include <linux/pci_hotplug.h>
  21#include <linux/delay.h>
  22#include <linux/mutex.h>
  23#include <linux/rwsem.h>
  24#include <linux/workqueue.h>
  25
  26#include "../pcie/portdrv.h"
  27
  28extern bool pciehp_poll_mode;
  29extern int pciehp_poll_time;
  30
  31/*
  32 * Set CONFIG_DYNAMIC_DEBUG=y and boot with 'dyndbg="file pciehp* +p"' to
  33 * enable debug messages.
  34 */
  35#define ctrl_dbg(ctrl, format, arg...)                                  \
  36        pci_dbg(ctrl->pcie->port, format, ## arg)
  37#define ctrl_err(ctrl, format, arg...)                                  \
  38        pci_err(ctrl->pcie->port, format, ## arg)
  39#define ctrl_info(ctrl, format, arg...)                                 \
  40        pci_info(ctrl->pcie->port, format, ## arg)
  41#define ctrl_warn(ctrl, format, arg...)                                 \
  42        pci_warn(ctrl->pcie->port, format, ## arg)
  43
  44#define SLOT_NAME_SIZE 10
  45
  46/**
  47 * struct controller - PCIe hotplug controller
  48 * @pcie: pointer to the controller's PCIe port service device
  49 * @slot_cap: cached copy of the Slot Capabilities register
  50 * @inband_presence_disabled: In-Band Presence Detect Disable supported by
  51 *      controller and disabled per spec recommendation (PCIe r5.0, appendix I
  52 *      implementation note)
  53 * @slot_ctrl: cached copy of the Slot Control register
  54 * @ctrl_lock: serializes writes to the Slot Control register
  55 * @cmd_started: jiffies when the Slot Control register was last written;
  56 *      the next write is allowed 1 second later, absent a Command Completed
  57 *      interrupt (PCIe r4.0, sec 6.7.3.2)
  58 * @cmd_busy: flag set on Slot Control register write, cleared by IRQ handler
  59 *      on reception of a Command Completed event
  60 * @queue: wait queue to wake up on reception of a Command Completed event,
  61 *      used for synchronous writes to the Slot Control register
  62 * @pending_events: used by the IRQ handler to save events retrieved from the
  63 *      Slot Status register for later consumption by the IRQ thread
  64 * @notification_enabled: whether the IRQ was requested successfully
  65 * @power_fault_detected: whether a power fault was detected by the hardware
  66 *      that has not yet been cleared by the user
  67 * @poll_thread: thread to poll for slot events if no IRQ is available,
  68 *      enabled with pciehp_poll_mode module parameter
  69 * @state: current state machine position
  70 * @state_lock: protects reads and writes of @state;
  71 *      protects scheduling, execution and cancellation of @button_work
  72 * @button_work: work item to turn the slot on or off after 5 seconds
  73 *      in response to an Attention Button press
  74 * @hotplug_slot: structure registered with the PCI hotplug core
  75 * @reset_lock: prevents access to the Data Link Layer Link Active bit in the
  76 *      Link Status register and to the Presence Detect State bit in the Slot
  77 *      Status register during a slot reset which may cause them to flap
  78 * @ist_running: flag to keep user request waiting while IRQ thread is running
  79 * @request_result: result of last user request submitted to the IRQ thread
  80 * @requester: wait queue to wake up on completion of user request,
  81 *      used for synchronous slot enable/disable request via sysfs
  82 *
  83 * PCIe hotplug has a 1:1 relationship between controller and slot, hence
  84 * unlike other drivers, the two aren't represented by separate structures.
  85 */
  86struct controller {
  87        struct pcie_device *pcie;
  88
  89        u32 slot_cap;                           /* capabilities and quirks */
  90        unsigned int inband_presence_disabled:1;
  91
  92        u16 slot_ctrl;                          /* control register access */
  93        struct mutex ctrl_lock;
  94        unsigned long cmd_started;
  95        unsigned int cmd_busy:1;
  96        wait_queue_head_t queue;
  97
  98        atomic_t pending_events;                /* event handling */
  99        unsigned int notification_enabled:1;
 100        unsigned int power_fault_detected;
 101        struct task_struct *poll_thread;
 102
 103        u8 state;                               /* state machine */
 104        struct mutex state_lock;
 105        struct delayed_work button_work;
 106
 107        struct hotplug_slot hotplug_slot;       /* hotplug core interface */
 108        struct rw_semaphore reset_lock;
 109        unsigned int ist_running;
 110        int request_result;
 111        wait_queue_head_t requester;
 112};
 113
 114/**
 115 * DOC: Slot state
 116 *
 117 * @OFF_STATE: slot is powered off, no subordinate devices are enumerated
 118 * @BLINKINGON_STATE: slot will be powered on after the 5 second delay,
 119 *      Power Indicator is blinking
 120 * @BLINKINGOFF_STATE: slot will be powered off after the 5 second delay,
 121 *      Power Indicator is blinking
 122 * @POWERON_STATE: slot is currently powering on
 123 * @POWEROFF_STATE: slot is currently powering off
 124 * @ON_STATE: slot is powered on, subordinate devices have been enumerated
 125 */
 126#define OFF_STATE                       0
 127#define BLINKINGON_STATE                1
 128#define BLINKINGOFF_STATE               2
 129#define POWERON_STATE                   3
 130#define POWEROFF_STATE                  4
 131#define ON_STATE                        5
 132
 133/**
 134 * DOC: Flags to request an action from the IRQ thread
 135 *
 136 * These are stored together with events read from the Slot Status register,
 137 * hence must be greater than its 16-bit width.
 138 *
 139 * %DISABLE_SLOT: Disable the slot in response to a user request via sysfs or
 140 *      an Attention Button press after the 5 second delay
 141 * %RERUN_ISR: Used by the IRQ handler to inform the IRQ thread that the
 142 *      hotplug port was inaccessible when the interrupt occurred, requiring
 143 *      that the IRQ handler is rerun by the IRQ thread after it has made the
 144 *      hotplug port accessible by runtime resuming its parents to D0
 145 */
 146#define DISABLE_SLOT            (1 << 16)
 147#define RERUN_ISR               (1 << 17)
 148
 149#define ATTN_BUTTN(ctrl)        ((ctrl)->slot_cap & PCI_EXP_SLTCAP_ABP)
 150#define POWER_CTRL(ctrl)        ((ctrl)->slot_cap & PCI_EXP_SLTCAP_PCP)
 151#define MRL_SENS(ctrl)          ((ctrl)->slot_cap & PCI_EXP_SLTCAP_MRLSP)
 152#define ATTN_LED(ctrl)          ((ctrl)->slot_cap & PCI_EXP_SLTCAP_AIP)
 153#define PWR_LED(ctrl)           ((ctrl)->slot_cap & PCI_EXP_SLTCAP_PIP)
 154#define NO_CMD_CMPL(ctrl)       ((ctrl)->slot_cap & PCI_EXP_SLTCAP_NCCS)
 155#define PSN(ctrl)               (((ctrl)->slot_cap & PCI_EXP_SLTCAP_PSN) >> 19)
 156
 157void pciehp_request(struct controller *ctrl, int action);
 158void pciehp_handle_button_press(struct controller *ctrl);
 159void pciehp_handle_disable_request(struct controller *ctrl);
 160void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events);
 161int pciehp_configure_device(struct controller *ctrl);
 162void pciehp_unconfigure_device(struct controller *ctrl, bool presence);
 163void pciehp_queue_pushbutton_work(struct work_struct *work);
 164struct controller *pcie_init(struct pcie_device *dev);
 165int pcie_init_notification(struct controller *ctrl);
 166void pcie_shutdown_notification(struct controller *ctrl);
 167void pcie_clear_hotplug_events(struct controller *ctrl);
 168void pcie_enable_interrupt(struct controller *ctrl);
 169void pcie_disable_interrupt(struct controller *ctrl);
 170int pciehp_power_on_slot(struct controller *ctrl);
 171void pciehp_power_off_slot(struct controller *ctrl);
 172void pciehp_get_power_status(struct controller *ctrl, u8 *status);
 173
 174#define INDICATOR_NOOP -1       /* Leave indicator unchanged */
 175void pciehp_set_indicators(struct controller *ctrl, int pwr, int attn);
 176
 177void pciehp_get_latch_status(struct controller *ctrl, u8 *status);
 178int pciehp_query_power_fault(struct controller *ctrl);
 179int pciehp_card_present(struct controller *ctrl);
 180int pciehp_card_present_or_link_active(struct controller *ctrl);
 181int pciehp_check_link_status(struct controller *ctrl);
 182int pciehp_check_link_active(struct controller *ctrl);
 183void pciehp_release_ctrl(struct controller *ctrl);
 184
 185int pciehp_sysfs_enable_slot(struct hotplug_slot *hotplug_slot);
 186int pciehp_sysfs_disable_slot(struct hotplug_slot *hotplug_slot);
 187int pciehp_reset_slot(struct hotplug_slot *hotplug_slot, bool probe);
 188int pciehp_get_attention_status(struct hotplug_slot *hotplug_slot, u8 *status);
 189int pciehp_set_raw_indicator_status(struct hotplug_slot *h_slot, u8 status);
 190int pciehp_get_raw_indicator_status(struct hotplug_slot *h_slot, u8 *status);
 191
 192static inline const char *slot_name(struct controller *ctrl)
 193{
 194        return hotplug_slot_name(&ctrl->hotplug_slot);
 195}
 196
 197static inline struct controller *to_ctrl(struct hotplug_slot *hotplug_slot)
 198{
 199        return container_of(hotplug_slot, struct controller, hotplug_slot);
 200}
 201
 202#endif                          /* _PCIEHP_H */
 203