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