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
  28#define MY_NAME "pciehp"
  29
  30extern bool pciehp_poll_mode;
  31extern int pciehp_poll_time;
  32extern bool pciehp_debug;
  33
  34#define dbg(format, arg...)                                             \
  35do {                                                                    \
  36        if (pciehp_debug)                                               \
  37                printk(KERN_DEBUG "%s: " format, MY_NAME, ## arg);      \
  38} while (0)
  39#define err(format, arg...)                                             \
  40        printk(KERN_ERR "%s: " format, MY_NAME, ## arg)
  41#define info(format, arg...)                                            \
  42        printk(KERN_INFO "%s: " format, MY_NAME, ## arg)
  43#define warn(format, arg...)                                            \
  44        printk(KERN_WARNING "%s: " format, MY_NAME, ## arg)
  45
  46#define ctrl_dbg(ctrl, format, arg...)                                  \
  47        do {                                                            \
  48                if (pciehp_debug)                                       \
  49                        dev_printk(KERN_DEBUG, &ctrl->pcie->device,     \
  50                                        format, ## arg);                \
  51        } while (0)
  52#define ctrl_err(ctrl, format, arg...)                                  \
  53        dev_err(&ctrl->pcie->device, format, ## arg)
  54#define ctrl_info(ctrl, format, arg...)                                 \
  55        dev_info(&ctrl->pcie->device, format, ## arg)
  56#define ctrl_warn(ctrl, format, arg...)                                 \
  57        dev_warn(&ctrl->pcie->device, format, ## arg)
  58
  59#define SLOT_NAME_SIZE 10
  60
  61/**
  62 * struct controller - PCIe hotplug controller
  63 * @pcie: pointer to the controller's PCIe port service device
  64 * @slot_cap: cached copy of the Slot Capabilities register
  65 * @slot_ctrl: cached copy of the Slot Control register
  66 * @ctrl_lock: serializes writes to the Slot Control register
  67 * @cmd_started: jiffies when the Slot Control register was last written;
  68 *      the next write is allowed 1 second later, absent a Command Completed
  69 *      interrupt (PCIe r4.0, sec 6.7.3.2)
  70 * @cmd_busy: flag set on Slot Control register write, cleared by IRQ handler
  71 *      on reception of a Command Completed event
  72 * @queue: wait queue to wake up on reception of a Command Completed event,
  73 *      used for synchronous writes to the Slot Control register
  74 * @pending_events: used by the IRQ handler to save events retrieved from the
  75 *      Slot Status register for later consumption by the IRQ thread
  76 * @notification_enabled: whether the IRQ was requested successfully
  77 * @power_fault_detected: whether a power fault was detected by the hardware
  78 *      that has not yet been cleared by the user
  79 * @poll_thread: thread to poll for slot events if no IRQ is available,
  80 *      enabled with pciehp_poll_mode module parameter
  81 * @state: current state machine position
  82 * @state_lock: protects reads and writes of @state;
  83 *      protects scheduling, execution and cancellation of @button_work
  84 * @button_work: work item to turn the slot on or off after 5 seconds
  85 *      in response to an Attention Button press
  86 * @hotplug_slot: structure registered with the PCI hotplug core
  87 * @reset_lock: prevents access to the Data Link Layer Link Active bit in the
  88 *      Link Status register and to the Presence Detect State bit in the Slot
  89 *      Status register during a slot reset which may cause them to flap
  90 * @request_result: result of last user request submitted to the IRQ thread
  91 * @requester: wait queue to wake up on completion of user request,
  92 *      used for synchronous slot enable/disable request via sysfs
  93 *
  94 * PCIe hotplug has a 1:1 relationship between controller and slot, hence
  95 * unlike other drivers, the two aren't represented by separate structures.
  96 */
  97struct controller {
  98        struct pcie_device *pcie;
  99
 100        u32 slot_cap;                           /* capabilities and quirks */
 101
 102        u16 slot_ctrl;                          /* control register access */
 103        struct mutex ctrl_lock;
 104        unsigned long cmd_started;
 105        unsigned int cmd_busy:1;
 106        wait_queue_head_t queue;
 107
 108        atomic_t pending_events;                /* event handling */
 109        unsigned int notification_enabled:1;
 110        unsigned int power_fault_detected;
 111        struct task_struct *poll_thread;
 112
 113        u8 state;                               /* state machine */
 114        struct mutex state_lock;
 115        struct delayed_work button_work;
 116
 117        struct hotplug_slot hotplug_slot;       /* hotplug core interface */
 118        struct rw_semaphore reset_lock;
 119        int request_result;
 120        wait_queue_head_t requester;
 121};
 122
 123/**
 124 * DOC: Slot state
 125 *
 126 * @OFF_STATE: slot is powered off, no subordinate devices are enumerated
 127 * @BLINKINGON_STATE: slot will be powered on after the 5 second delay,
 128 *      green led is blinking
 129 * @BLINKINGOFF_STATE: slot will be powered off after the 5 second delay,
 130 *      green led is blinking
 131 * @POWERON_STATE: slot is currently powering on
 132 * @POWEROFF_STATE: slot is currently powering off
 133 * @ON_STATE: slot is powered on, subordinate devices have been enumerated
 134 */
 135#define OFF_STATE                       0
 136#define BLINKINGON_STATE                1
 137#define BLINKINGOFF_STATE               2
 138#define POWERON_STATE                   3
 139#define POWEROFF_STATE                  4
 140#define ON_STATE                        5
 141
 142/**
 143 * DOC: Flags to request an action from the IRQ thread
 144 *
 145 * These are stored together with events read from the Slot Status register,
 146 * hence must be greater than its 16-bit width.
 147 *
 148 * %DISABLE_SLOT: Disable the slot in response to a user request via sysfs or
 149 *      an Attention Button press after the 5 second delay
 150 * %RERUN_ISR: Used by the IRQ handler to inform the IRQ thread that the
 151 *      hotplug port was inaccessible when the interrupt occurred, requiring
 152 *      that the IRQ handler is rerun by the IRQ thread after it has made the
 153 *      hotplug port accessible by runtime resuming its parents to D0
 154 */
 155#define DISABLE_SLOT            (1 << 16)
 156#define RERUN_ISR               (1 << 17)
 157
 158#define ATTN_BUTTN(ctrl)        ((ctrl)->slot_cap & PCI_EXP_SLTCAP_ABP)
 159#define POWER_CTRL(ctrl)        ((ctrl)->slot_cap & PCI_EXP_SLTCAP_PCP)
 160#define MRL_SENS(ctrl)          ((ctrl)->slot_cap & PCI_EXP_SLTCAP_MRLSP)
 161#define ATTN_LED(ctrl)          ((ctrl)->slot_cap & PCI_EXP_SLTCAP_AIP)
 162#define PWR_LED(ctrl)           ((ctrl)->slot_cap & PCI_EXP_SLTCAP_PIP)
 163#define HP_SUPR_RM(ctrl)        ((ctrl)->slot_cap & PCI_EXP_SLTCAP_HPS)
 164#define EMI(ctrl)               ((ctrl)->slot_cap & PCI_EXP_SLTCAP_EIP)
 165#define NO_CMD_CMPL(ctrl)       ((ctrl)->slot_cap & PCI_EXP_SLTCAP_NCCS)
 166#define PSN(ctrl)               (((ctrl)->slot_cap & PCI_EXP_SLTCAP_PSN) >> 19)
 167
 168void pciehp_request(struct controller *ctrl, int action);
 169void pciehp_handle_button_press(struct controller *ctrl);
 170void pciehp_handle_disable_request(struct controller *ctrl);
 171void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events);
 172int pciehp_configure_device(struct controller *ctrl);
 173void pciehp_unconfigure_device(struct controller *ctrl, bool presence);
 174void pciehp_queue_pushbutton_work(struct work_struct *work);
 175struct controller *pcie_init(struct pcie_device *dev);
 176int pcie_init_notification(struct controller *ctrl);
 177void pcie_shutdown_notification(struct controller *ctrl);
 178void pcie_clear_hotplug_events(struct controller *ctrl);
 179int pciehp_power_on_slot(struct controller *ctrl);
 180void pciehp_power_off_slot(struct controller *ctrl);
 181void pciehp_get_power_status(struct controller *ctrl, u8 *status);
 182
 183void pciehp_set_attention_status(struct controller *ctrl, u8 status);
 184void pciehp_get_latch_status(struct controller *ctrl, u8 *status);
 185int pciehp_query_power_fault(struct controller *ctrl);
 186void pciehp_green_led_on(struct controller *ctrl);
 187void pciehp_green_led_off(struct controller *ctrl);
 188void pciehp_green_led_blink(struct controller *ctrl);
 189bool pciehp_card_present(struct controller *ctrl);
 190bool pciehp_card_present_or_link_active(struct controller *ctrl);
 191int pciehp_check_link_status(struct controller *ctrl);
 192bool pciehp_check_link_active(struct controller *ctrl);
 193void pciehp_release_ctrl(struct controller *ctrl);
 194
 195int pciehp_sysfs_enable_slot(struct hotplug_slot *hotplug_slot);
 196int pciehp_sysfs_disable_slot(struct hotplug_slot *hotplug_slot);
 197int pciehp_reset_slot(struct hotplug_slot *hotplug_slot, int probe);
 198int pciehp_get_attention_status(struct hotplug_slot *hotplug_slot, u8 *status);
 199int pciehp_set_raw_indicator_status(struct hotplug_slot *h_slot, u8 status);
 200int pciehp_get_raw_indicator_status(struct hotplug_slot *h_slot, u8 *status);
 201
 202static inline const char *slot_name(struct controller *ctrl)
 203{
 204        return hotplug_slot_name(&ctrl->hotplug_slot);
 205}
 206
 207static inline struct controller *to_ctrl(struct hotplug_slot *hotplug_slot)
 208{
 209        return container_of(hotplug_slot, struct controller, hotplug_slot);
 210}
 211
 212#endif                          /* _PCIEHP_H */
 213