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