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  * @ist_running: flag to keep user request waiting while IRQ thread is running
  76  * @request_result: result of last user request submitted to the IRQ thread
  77  * @requester: wait queue to wake up on completion of user request,
  78  *      used for synchronous slot enable/disable request via sysfs
  79  *
  80  * PCIe hotplug has a 1:1 relationship between controller and slot, hence
  81  * unlike other drivers, the two aren't represented by separate structures.
  82  */
  83 struct controller {
  84         struct pcie_device *pcie;
  85
  86         u32 slot_cap;                           /* capabilities and quirks */
  87         unsigned int inband_presence_disabled:1;
  88
  89         u16 slot_ctrl;                          /* control register access */
  90         struct mutex ctrl_lock;
  91         unsigned long cmd_started;
  92         unsigned int cmd_busy:1;
  93         wait_queue_head_t queue;
  94
  95         atomic_t pending_events;                /* event handling */
  96         unsigned int notification_enabled:1;
  97         unsigned int power_fault_detected;
  98         struct task_struct *poll_thread;
  99
 100         u8 state;                               /* state machine */
 101         struct mutex state_lock;
 102         struct delayed_work button_work;
 103
 104         struct hotplug_slot hotplug_slot;       /* hotplug core interface */
 105         struct rw_semaphore reset_lock;
 106         unsigned int ist_running;
 107         int request_result;
 108         wait_queue_head_t requester;
 109 };
 110
 111 /**
 112  * DOC: Slot state
 113  *
 114  * @OFF_STATE: slot is powered off, no subordinate devices are enumerated
 115  * @BLINKINGON_STATE: slot will be powered on after the 5 second delay,
 116  *      Power Indicator is blinking
 117  * @BLINKINGOFF_STATE: slot will be powered off after the 5 second delay,
 118  *      Power Indicator is blinking
 119  * @POWERON_STATE: slot is currently powering on
 120  * @POWEROFF_STATE: slot is currently powering off
 121  * @ON_STATE: slot is powered on, subordinate devices have been enumerated
 122  */
 123 #define OFF_STATE                       0
 124 #define BLINKINGON_STATE                1
 125 #define BLINKINGOFF_STATE               2
 126 #define POWERON_STATE                   3
 127 #define POWEROFF_STATE                  4
 128 #define ON_STATE                        5
 129
 130 /**
 131  * DOC: Flags to request an action from the IRQ thread
 132  *
 133  * These are stored together with events read from the Slot Status register,
 134  * hence must be greater than its 16-bit width.
 135  *
 136  * %DISABLE_SLOT: Disable the slot in response to a user request via sysfs or
 137  *      an Attention Button press after the 5 second delay
 138  * %RERUN_ISR: Used by the IRQ handler to inform the IRQ thread that the
 139  *      hotplug port was inaccessible when the interrupt occurred, requiring
 140  *      that the IRQ handler is rerun by the IRQ thread after it has made the
 141  *      hotplug port accessible by runtime resuming its parents to D0
 142  */
 143 #define DISABLE_SLOT            (1 << 16)
 144 #define RERUN_ISR               (1 << 17)
 145
 146 #define ATTN_BUTTN(ctrl)        ((ctrl)->slot_cap & PCI_EXP_SLTCAP_ABP)
 147 #define POWER_CTRL(ctrl)        ((ctrl)->slot_cap & PCI_EXP_SLTCAP_PCP)
 148 #define MRL_SENS(ctrl)          ((ctrl)->slot_cap & PCI_EXP_SLTCAP_MRLSP)
 149 #define ATTN_LED(ctrl)          ((ctrl)->slot_cap & PCI_EXP_SLTCAP_AIP)
 150 #define PWR_LED(ctrl)           ((ctrl)->slot_cap & PCI_EXP_SLTCAP_PIP)
 151 #define NO_CMD_CMPL(ctrl)       ((ctrl)->slot_cap & PCI_EXP_SLTCAP_NCCS)
 152 #define PSN(ctrl)               (((ctrl)->slot_cap & PCI_EXP_SLTCAP_PSN) >> 19)
 153
 154 void pciehp_request(struct controller *ctrl, int action);
 155 void pciehp_handle_button_press(struct controller *ctrl);
 156 void pciehp_handle_disable_request(struct controller *ctrl);
 157 void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events);
 158 int pciehp_configure_device(struct controller *ctrl);
 159 void pciehp_unconfigure_device(struct controller *ctrl, bool presence);
 160 void pciehp_queue_pushbutton_work(struct work_struct *work);
 161 struct controller *pcie_init(struct pcie_device *dev);
 162 int pcie_init_notification(struct controller *ctrl);
 163 void pcie_shutdown_notification(struct controller *ctrl);
 164 void pcie_clear_hotplug_events(struct controller *ctrl);
 165 void pcie_enable_interrupt(struct controller *ctrl);
 166 void pcie_disable_interrupt(struct controller *ctrl);
 167 int pciehp_power_on_slot(struct controller *ctrl);
 168 void pciehp_power_off_slot(struct controller *ctrl);
 169 void pciehp_get_power_status(struct controller *ctrl, u8 *status);
 170
 171 #define INDICATOR_NOOP -1       /* Leave indicator unchanged */
 172 void pciehp_set_indicators(struct controller *ctrl, int pwr, int attn);
 173
 174 void pciehp_get_latch_status(struct controller *ctrl, u8 *status);
 175 int pciehp_query_power_fault(struct controller *ctrl);
 176 int pciehp_card_present(struct controller *ctrl);
 177 int pciehp_card_present_or_link_active(struct controller *ctrl);
 178 int pciehp_check_link_status(struct controller *ctrl);
 179 int 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 */